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Increased consumption and increased use of renewable energy make overhead lines and transformers more often congested. Dynamic rating (DR) uses a time-depending maximum permissible current instead of a long-term-fixed rating; it is an effective solution to upgrade the capacity of existing grid assets to minimize this congestion. Dynamic line rating (DLR) considers how the weather affects the thermal behavior of the conductor and therewith its rating; environmental parameters as well as conductor characteristics have to be considered. Likewise, dynamic rating of transformers (DTR) relies on a thermal assessment of the hottest spot in the transformer windings. The hot-spot temperature is dependent on the ambient temperature, loading, and transformer’s cooling system. In this thesis, a number of lesser-studied aspects of DR are studied: stochastic modeling of the rating; relations between protection, reliability and rating; risk assessment for line selection when using DLR; and increased transformer hosting capacity (HC) in the presence of solar photovoltaic (PV). In the first part of the work, the focus is on the stochastic modeling of DLR and its relation to the protection operation. Actual line rating is considered a random variable in the protection system for a more flexible decision-making. Different sources of uncertainties are modeled using suitable probability density functions. The method allows for a transparent trade-off between the risk of failure to take measures and the risk of unnecessary measures against overload. The results depicts that deterministic DLR could result in high probabilities of overloading or would require large safety margins. While, a stochastic approach will allow for both small margins and appropriate risks. A generic model is introduced to consider DLR reliability from two different viewpoints: errors and failures of components that would affect the calculation of the rating; and the impact of a DLR failure on the power system. T

Increased consumption and increased use of renewable energy make overhead lines and transformers more often congested. Dynamic rating (DR) uses a time-depending maximum permissible current instead of a long-term-fixed rating; it is an effective solution to upgrade the capacity of existing grid assets to minimize this congestion. Dynamic line rating (DLR) considers how the weather affects the thermal behavior of the conductor and therewith its rating; environmental parameters as well as conductor characteristics have to be considered. Likewise, dynamic rating of transformers (DTR) relies on a thermal assessment of the hottest spot in the transformer windings. The hot-spot temperature is dependent on the ambient temperature, loading, and transformer’s cooling system. In this thesis, a number of lesser-studied aspects of DR are studied: stochastic modeling of the rating; relations between protection, reliability and rating; risk assessment for line selection when using DLR; and increased transformer hosting capacity (HC) in the presence of solar photovoltaic (PV). In the first part of the work, the focus is on the stochastic modeling of DLR and its relation to the protection operation. Actual line rating is considered a random variable in the protection system for a more flexible decision-making. Different sources of uncertainties are modeled using suitable probability density functions. The method allows for a transparent trade-off between the risk of failure to take measures and the risk of unnecessary measures against overload. The results depicts that deterministic DLR could result in high probabilities of overloading or would require large safety margins. While, a stochastic approach will allow for both small margins and appropriate risks. A generic model is introduced to consider DLR reliability from two different viewpoints: errors and failures of components that would affect the calculation of the rating; and the impact of a DLR failure on the power system. T

Dynamic rating (DR) of power components is a method for assessing real-time capacity of large scale power transmission and distribution devices (commonly: transmission lines, power transformers, underground cables) and using this knowledge for adjusting loading limits of these components. Dynamic rating of power lines or dynamic line rating (DLR) is a pioneering technology in the area of dynamic rating. Heat balance of an overhead conductor is a defining factor when designing capacity limits for power lines. The maximum ampacity of the power line depends on the factors, such as ambient temperature, wind speed, wind direction, solar radiation, humidity, location, height above the sea level and conductor dimensions and material properties. Dynamic transformer rating (DTR) is a new emerging technology with high interest from industry and academia. Similarly to DLR, the dynamic rating of transformers relies on a thermal assessment of the device by locating the hottest spot in the transformer windings. The hot-spot temperature is the limiting factor for determining the maximum allowable ampacity. By shifting from the power-constrained the loading limits to the temperature-constrained, it is possible to achieve much better utilization of power transformer. Recently, DLR became a recognizable concept in the power systems research community; DTR is also slowly gaining its popularity among researchers. At the same time, the industry begins to recognize DR benefits and invest in dynamic rating technologies. However, there exist many unanswered questions to the technology's reliability, applicability and safe operation. One of the central questions is: how to integrate dynamic rating into short term and long term planning decisions? he results of the work presented in this thesis show that dynamic rating has high potential to improve power system performance and reduce the costs for power dispatch and increase the share of the renewable energy in the electricity mix. Togethe, Dynamisk rating (DR) av elkraftkomponenter syftar till tekniker för att uppskatta kapaciteten hos komponenter för storskalig överföring av elkraft (vanligtvis: kraftledningar, transformatorer, underjordiska kablar) i realtid och använda denna information för att justera belastningsgränserna för dessa. Dynamisk rating av kraftledningar (DLR) är en nydanande teknik inom detta område. Värmebalansen för en kraftledning är en viktig faktor för att bestämma dess överföringskapacitet. En kraftlednings maximala strömledningsförmåga beror därför på faktorer så som temperatur, vindhastighet, vindriktning, solstrålning, fuktighet, geografiskt läge, höjd över havet och ledarens dimensioner och materialegenskaper. Dynamisk rating av transformatorer (DTR) är en ny teknik med stort intresse från industri och akademi. Liknande som för DLR använder sig DTR av en uppskattning av den hot-spot temperaturen, hos komponenten genom att hitta den varmaste punkten i transformatorlindningarna. Hot-spot temperaturen är den begränsande faktorn för att avgöra transformatorns överföringskapacitet. Genom att låta den maximalt tillåtna belastningen bero på temperaturen istället för effekten kan utnyttjandet av transformatorn förbättras väsentligt. Nyligen har DLR blivit ett erkänt koncept inom forskningen för elkraft och DTR har också börjat bli populärt bland forskare. Samtidigt har industrin börjat se fördelarna av DR och investera i dessa tekniker. Det finns dock fortfarande många frågor kring teknikern som rör tillförlitlighet, applicerbarhet och säkerhet. En av de viktigaste frågorna är hur man bäst kan integrera dynamisk rating i kort- och långtidsplaneringen av elkraftsystem. Resultaten av arbetet som presenteras i denna avhandling visar att dynamisk rating har en stor potential att minska kostnaderna för driften av elnätet och tillåta integrering av mer förnybara energikällor. Dessutom kan dynamisk rating göra förnybar energi mer tillgänglig genom att minska de investeringar som krävs fö, QC 20200109

Dynamic rating (DR) of power components is a method for assessing real-time capacity of large scale power transmission and distribution devices (commonly: transmission lines, power transformers, underground cables) and using this knowledge for adjusting loading limits of these components. Dynamic rating of power lines or dynamic line rating (DLR) is a pioneering technology in the area of dynamic rating. Heat balance of an overhead conductor is a defining factor when designing capacity limits for power lines. The maximum ampacity of the power line depends on the factors, such as ambient temperature, wind speed, wind direction, solar radiation, humidity, location, height above the sea level and conductor dimensions and material properties. Dynamic transformer rating (DTR) is a new emerging technology with high interest from industry and academia. Similarly to DLR, the dynamic rating of transformers relies on a thermal assessment of the device by locating the hottest spot in the transformer windings. The hot-spot temperature is the limiting factor for determining the maximum allowable ampacity. By shifting from the power-constrained the loading limits to the temperature-constrained, it is possible to achieve much better utilization of power transformer. Recently, DLR became a recognizable concept in the power systems research community; DTR is also slowly gaining its popularity among researchers. At the same time, the industry begins to recognize DR benefits and invest in dynamic rating technologies. However, there exist many unanswered questions to the technology's reliability, applicability and safe operation. One of the central questions is: how to integrate dynamic rating into short term and long term planning decisions? he results of the work presented in this thesis show that dynamic rating has high potential to improve power system performance and reduce the costs for power dispatch and increase the share of the renewable energy in the electricity mix. Togethe, Dynamisk rating (DR) av elkraftkomponenter syftar till tekniker för att uppskatta kapaciteten hos komponenter för storskalig överföring av elkraft (vanligtvis: kraftledningar, transformatorer, underjordiska kablar) i realtid och använda denna information för att justera belastningsgränserna för dessa. Dynamisk rating av kraftledningar (DLR) är en nydanande teknik inom detta område. Värmebalansen för en kraftledning är en viktig faktor för att bestämma dess överföringskapacitet. En kraftlednings maximala strömledningsförmåga beror därför på faktorer så som temperatur, vindhastighet, vindriktning, solstrålning, fuktighet, geografiskt läge, höjd över havet och ledarens dimensioner och materialegenskaper. Dynamisk rating av transformatorer (DTR) är en ny teknik med stort intresse från industri och akademi. Liknande som för DLR använder sig DTR av en uppskattning av den hot-spot temperaturen, hos komponenten genom att hitta den varmaste punkten i transformatorlindningarna. Hot-spot temperaturen är den begränsande faktorn för att avgöra transformatorns överföringskapacitet. Genom att låta den maximalt tillåtna belastningen bero på temperaturen istället för effekten kan utnyttjandet av transformatorn förbättras väsentligt. Nyligen har DLR blivit ett erkänt koncept inom forskningen för elkraft och DTR har också börjat bli populärt bland forskare. Samtidigt har industrin börjat se fördelarna av DR och investera i dessa tekniker. Det finns dock fortfarande många frågor kring teknikern som rör tillförlitlighet, applicerbarhet och säkerhet. En av de viktigaste frågorna är hur man bäst kan integrera dynamisk rating i kort- och långtidsplaneringen av elkraftsystem. Resultaten av arbetet som presenteras i denna avhandling visar att dynamisk rating har en stor potential att minska kostnaderna för driften av elnätet och tillåta integrering av mer förnybara energikällor. Dessutom kan dynamisk rating göra förnybar energi mer tillgänglig genom att minska de investeringar som krävs fö, QC 20200109

Dynamic rating (DR) of power components is a method for assessing real-time capacity of large scale power transmission and distribution devices (commonly: transmission lines, power transformers, underground cables) and using this knowledge for adjusting loading limits of these components. Dynamic rating of power lines or dynamic line rating (DLR) is a pioneering technology in the area of dynamic rating. Heat balance of an overhead conductor is a defining factor when designing capacity limits for power lines. The maximum ampacity of the power line depends on the factors, such as ambient temperature, wind speed, wind direction, solar radiation, humidity, location, height above the sea level and conductor dimensions and material properties. Dynamic transformer rating (DTR) is a new emerging technology with high interest from industry and academia. Similarly to DLR, the dynamic rating of transformers relies on a thermal assessment of the device by locating the hottest spot in the transformer windings. The hot-spot temperature is the limiting factor for determining the maximum allowable ampacity. By shifting from the power-constrained the loading limits to the temperature-constrained, it is possible to achieve much better utilization of power transformer. Recently, DLR became a recognizable concept in the power systems research community; DTR is also slowly gaining its popularity among researchers. At the same time, the industry begins to recognize DR benefits and invest in dynamic rating technologies. However, there exist many unanswered questions to the technology's reliability, applicability and safe operation. One of the central questions is: how to integrate dynamic rating into short term and long term planning decisions? he results of the work presented in this thesis show that dynamic rating has high potential to improve power system performance and reduce the costs for power dispatch and increase the share of the renewable energy in the electricity mix. Togethe, Dynamisk rating (DR) av elkraftkomponenter syftar till tekniker för att uppskatta kapaciteten hos komponenter för storskalig överföring av elkraft (vanligtvis: kraftledningar, transformatorer, underjordiska kablar) i realtid och använda denna information för att justera belastningsgränserna för dessa. Dynamisk rating av kraftledningar (DLR) är en nydanande teknik inom detta område. Värmebalansen för en kraftledning är en viktig faktor för att bestämma dess överföringskapacitet. En kraftlednings maximala strömledningsförmåga beror därför på faktorer så som temperatur, vindhastighet, vindriktning, solstrålning, fuktighet, geografiskt läge, höjd över havet och ledarens dimensioner och materialegenskaper. Dynamisk rating av transformatorer (DTR) är en ny teknik med stort intresse från industri och akademi. Liknande som för DLR använder sig DTR av en uppskattning av den hot-spot temperaturen, hos komponenten genom att hitta den varmaste punkten i transformatorlindningarna. Hot-spot temperaturen är den begränsande faktorn för att avgöra transformatorns överföringskapacitet. Genom att låta den maximalt tillåtna belastningen bero på temperaturen istället för effekten kan utnyttjandet av transformatorn förbättras väsentligt. Nyligen har DLR blivit ett erkänt koncept inom forskningen för elkraft och DTR har också börjat bli populärt bland forskare. Samtidigt har industrin börjat se fördelarna av DR och investera i dessa tekniker. Det finns dock fortfarande många frågor kring teknikern som rör tillförlitlighet, applicerbarhet och säkerhet. En av de viktigaste frågorna är hur man bäst kan integrera dynamisk rating i kort- och långtidsplaneringen av elkraftsystem. Resultaten av arbetet som presenteras i denna avhandling visar att dynamisk rating har en stor potential att minska kostnaderna för driften av elnätet och tillåta integrering av mer förnybara energikällor. Dessutom kan dynamisk rating göra förnybar energi mer tillgänglig genom att minska de investeringar som krävs fö, QC 20200109

Dynamic rating (DR) of power components is a method for assessing real-time capacity of large scale power transmission and distribution devices (commonly: transmission lines, power transformers, underground cables) and using this knowledge for adjusting loading limits of these components. Dynamic rating of power lines or dynamic line rating (DLR) is a pioneering technology in the area of dynamic rating. Heat balance of an overhead conductor is a defining factor when designing capacity limits for power lines. The maximum ampacity of the power line depends on the factors, such as ambient temperature, wind speed, wind direction, solar radiation, humidity, location, height above the sea level and conductor dimensions and material properties. Dynamic transformer rating (DTR) is a new emerging technology with high interest from industry and academia. Similarly to DLR, the dynamic rating of transformers relies on a thermal assessment of the device by locating the hottest spot in the transformer windings. The hot-spot temperature is the limiting factor for determining the maximum allowable ampacity. By shifting from the power-constrained the loading limits to the temperature-constrained, it is possible to achieve much better utilization of power transformer. Recently, DLR became a recognizable concept in the power systems research community; DTR is also slowly gaining its popularity among researchers. At the same time, the industry begins to recognize DR benefits and invest in dynamic rating technologies. However, there exist many unanswered questions to the technology's reliability, applicability and safe operation. One of the central questions is: how to integrate dynamic rating into short term and long term planning decisions? he results of the work presented in this thesis show that dynamic rating has high potential to improve power system performance and reduce the costs for power dispatch and increase the share of the renewable energy in the electricity mix. Togethe, Dynamisk rating (DR) av elkraftkomponenter syftar till tekniker för att uppskatta kapaciteten hos komponenter för storskalig överföring av elkraft (vanligtvis: kraftledningar, transformatorer, underjordiska kablar) i realtid och använda denna information för att justera belastningsgränserna för dessa. Dynamisk rating av kraftledningar (DLR) är en nydanande teknik inom detta område. Värmebalansen för en kraftledning är en viktig faktor för att bestämma dess överföringskapacitet. En kraftlednings maximala strömledningsförmåga beror därför på faktorer så som temperatur, vindhastighet, vindriktning, solstrålning, fuktighet, geografiskt läge, höjd över havet och ledarens dimensioner och materialegenskaper. Dynamisk rating av transformatorer (DTR) är en ny teknik med stort intresse från industri och akademi. Liknande som för DLR använder sig DTR av en uppskattning av den hot-spot temperaturen, hos komponenten genom att hitta den varmaste punkten i transformatorlindningarna. Hot-spot temperaturen är den begränsande faktorn för att avgöra transformatorns överföringskapacitet. Genom att låta den maximalt tillåtna belastningen bero på temperaturen istället för effekten kan utnyttjandet av transformatorn förbättras väsentligt. Nyligen har DLR blivit ett erkänt koncept inom forskningen för elkraft och DTR har också börjat bli populärt bland forskare. Samtidigt har industrin börjat se fördelarna av DR och investera i dessa tekniker. Det finns dock fortfarande många frågor kring teknikern som rör tillförlitlighet, applicerbarhet och säkerhet. En av de viktigaste frågorna är hur man bäst kan integrera dynamisk rating i kort- och långtidsplaneringen av elkraftsystem. Resultaten av arbetet som presenteras i denna avhandling visar att dynamisk rating har en stor potential att minska kostnaderna för driften av elnätet och tillåta integrering av mer förnybara energikällor. Dessutom kan dynamisk rating göra förnybar energi mer tillgänglig genom att minska de investeringar som krävs fö, QC 20200109

Dynamic rating (DR) of power components is a method for assessing real-time capacity of large scale power transmission and distribution devices (commonly: transmission lines, power transformers, underground cables) and using this knowledge for adjusting loading limits of these components. Dynamic rating of power lines or dynamic line rating (DLR) is a pioneering technology in the area of dynamic rating. Heat balance of an overhead conductor is a defining factor when designing capacity limits for power lines. The maximum ampacity of the power line depends on the factors, such as ambient temperature, wind speed, wind direction, solar radiation, humidity, location, height above the sea level and conductor dimensions and material properties. Dynamic transformer rating (DTR) is a new emerging technology with high interest from industry and academia. Similarly to DLR, the dynamic rating of transformers relies on a thermal assessment of the device by locating the hottest spot in the transformer windings. The hot-spot temperature is the limiting factor for determining the maximum allowable ampacity. By shifting from the power-constrained the loading limits to the temperature-constrained, it is possible to achieve much better utilization of power transformer. Recently, DLR became a recognizable concept in the power systems research community; DTR is also slowly gaining its popularity among researchers. At the same time, the industry begins to recognize DR benefits and invest in dynamic rating technologies. However, there exist many unanswered questions to the technology's reliability, applicability and safe operation. One of the central questions is: how to integrate dynamic rating into short term and long term planning decisions? he results of the work presented in this thesis show that dynamic rating has high potential to improve power system performance and reduce the costs for power dispatch and increase the share of the renewable energy in the electricity mix. Togethe, Dynamisk rating (DR) av elkraftkomponenter syftar till tekniker för att uppskatta kapaciteten hos komponenter för storskalig överföring av elkraft (vanligtvis: kraftledningar, transformatorer, underjordiska kablar) i realtid och använda denna information för att justera belastningsgränserna för dessa. Dynamisk rating av kraftledningar (DLR) är en nydanande teknik inom detta område. Värmebalansen för en kraftledning är en viktig faktor för att bestämma dess överföringskapacitet. En kraftlednings maximala strömledningsförmåga beror därför på faktorer så som temperatur, vindhastighet, vindriktning, solstrålning, fuktighet, geografiskt läge, höjd över havet och ledarens dimensioner och materialegenskaper. Dynamisk rating av transformatorer (DTR) är en ny teknik med stort intresse från industri och akademi. Liknande som för DLR använder sig DTR av en uppskattning av den hot-spot temperaturen, hos komponenten genom att hitta den varmaste punkten i transformatorlindningarna. Hot-spot temperaturen är den begränsande faktorn för att avgöra transformatorns överföringskapacitet. Genom att låta den maximalt tillåtna belastningen bero på temperaturen istället för effekten kan utnyttjandet av transformatorn förbättras väsentligt. Nyligen har DLR blivit ett erkänt koncept inom forskningen för elkraft och DTR har också börjat bli populärt bland forskare. Samtidigt har industrin börjat se fördelarna av DR och investera i dessa tekniker. Det finns dock fortfarande många frågor kring teknikern som rör tillförlitlighet, applicerbarhet och säkerhet. En av de viktigaste frågorna är hur man bäst kan integrera dynamisk rating i kort- och långtidsplaneringen av elkraftsystem. Resultaten av arbetet som presenteras i denna avhandling visar att dynamisk rating har en stor potential att minska kostnaderna för driften av elnätet och tillåta integrering av mer förnybara energikällor. Dessutom kan dynamisk rating göra förnybar energi mer tillgänglig genom att minska de investeringar som krävs fö, QC 20200109

[ES] La exigencia sobre los sistemas de transporte se ha incrementado considerablemente los últimos años debido al rápido crecimiento de la demanda eléctrica. La Gestión Activa de la Demanda y la monitorización dinámica de líneas juegan un papel importante en la mejora de los problemas a los que se enfrentan hoy en día las líneas de transporte aéreas. En este documento se lleva a cabo una monitorización dinámica de la línea Abanto-Castro y se estudia la posibilidad de aplicación de estrategias de Gestión Activa de la Demanda sobre la misma. Palabras clave: gestión activa, demanda, monitorización dinámica, líneas., [EU] Garraio-sistemen gaineko eskakizuna nabarmen hazi da azken urteetan, eskaera elektrikoak izandako hazkunde azkarra dela eta. Eskaeraren Kudeaketa Aktiboak eta aireko lineen jarraipen dinamikoak zeregin garrantzitsua betetzen dute gaur egungo aireko garraio lineek aurre egin beharreko arazoak hobetzeko. Dokumentu honetan, Abanto-Castro aire lineko jarraipen dinamikoa egiten da, baita hartan eskaeraren kudeaketa aktiboaren estrategiak aplikatzeko aukera aztertu ere. Hitz gakoak: kudeaketa,eskari elektrikoa, jarraipen dinamikoa, aire lineak., [EN] The demand on transmission systems has increased considerably in recent years due to the rapid growth of electricity demand. Demand Side Management and Dynamic Line Rating play an important role in improving the problems that air transmission lines face today. In this document, a Dynamic Rating of the Abanto-Castro line is carried out and the possibility of applying any Demand Side Management strategies on it is studied. Key words: Side Management, demand, Dynamic Rating, lines.

[ES] La exigencia sobre los sistemas de transporte se ha incrementado considerablemente los últimos años debido al rápido crecimiento de la demanda eléctrica. La Gestión Activa de la Demanda y la monitorización dinámica de líneas juegan un papel importante en la mejora de los problemas a los que se enfrentan hoy en día las líneas de transporte aéreas. En este documento se lleva a cabo una monitorización dinámica de la línea Abanto-Castro y se estudia la posibilidad de aplicación de estrategias de Gestión Activa de la Demanda sobre la misma. Palabras clave: gestión activa, demanda, monitorización dinámica, líneas., [EU] Garraio-sistemen gaineko eskakizuna nabarmen hazi da azken urteetan, eskaera elektrikoak izandako hazkunde azkarra dela eta. Eskaeraren Kudeaketa Aktiboak eta aireko lineen jarraipen dinamikoak zeregin garrantzitsua betetzen dute gaur egungo aireko garraio lineek aurre egin beharreko arazoak hobetzeko. Dokumentu honetan, Abanto-Castro aire lineko jarraipen dinamikoa egiten da, baita hartan eskaeraren kudeaketa aktiboaren estrategiak aplikatzeko aukera aztertu ere. Hitz gakoak: kudeaketa,eskari elektrikoa, jarraipen dinamikoa, aire lineak., [EN] The demand on transmission systems has increased considerably in recent years due to the rapid growth of electricity demand. Demand Side Management and Dynamic Line Rating play an important role in improving the problems that air transmission lines face today. In this document, a Dynamic Rating of the Abanto-Castro line is carried out and the possibility of applying any Demand Side Management strategies on it is studied. Key words: Side Management, demand, Dynamic Rating, lines.

[ES] La exigencia sobre los sistemas de transporte se ha incrementado considerablemente los últimos años debido al rápido crecimiento de la demanda eléctrica. La Gestión Activa de la Demanda y la monitorización dinámica de líneas juegan un papel importante en la mejora de los problemas a los que se enfrentan hoy en día las líneas de transporte aéreas. En este documento se lleva a cabo una monitorización dinámica de la línea Abanto-Castro y se estudia la posibilidad de aplicación de estrategias de Gestión Activa de la Demanda sobre la misma. Palabras clave: gestión activa, demanda, monitorización dinámica, líneas., [EU] Garraio-sistemen gaineko eskakizuna nabarmen hazi da azken urteetan, eskaera elektrikoak izandako hazkunde azkarra dela eta. Eskaeraren Kudeaketa Aktiboak eta aireko lineen jarraipen dinamikoak zeregin garrantzitsua betetzen dute gaur egungo aireko garraio lineek aurre egin beharreko arazoak hobetzeko. Dokumentu honetan, Abanto-Castro aire lineko jarraipen dinamikoa egiten da, baita hartan eskaeraren kudeaketa aktiboaren estrategiak aplikatzeko aukera aztertu ere. Hitz gakoak: kudeaketa,eskari elektrikoa, jarraipen dinamikoa, aire lineak., [EN] The demand on transmission systems has increased considerably in recent years due to the rapid growth of electricity demand. Demand Side Management and Dynamic Line Rating play an important role in improving the problems that air transmission lines face today. In this document, a Dynamic Rating of the Abanto-Castro line is carried out and the possibility of applying any Demand Side Management strategies on it is studied. Key words: Side Management, demand, Dynamic Rating, lines.

A state-of-the-art review of the optimization of electrical cables in Offshore Wind Farms (OWFs) is presented in this paper. One of the main contributions of this work is to propose a general classification of this problem, framed in the general context of the Offshore Wind Farms Design and Optimization (OWiFDO). The classification encompasses two complementary aspects. First, the optimum sizing of electrical cables, with the three main approaches used nowadays: static rated sizing, dynamic load cycle profile, and dynamic full time series, being conceptually analyzed and compared. The latest techniques and advances are described, along with the presentation of potential research areas not thoroughly addressed today, such as Dynamic Cable Rating, and cable’s lifetime estimation under time-varying conditions. Second, the network optimization of large OWFs is thoroughly presented, dividing the problem with a bottom-top approach: cable layout of collection system, Wind Turbines (WTs) allocation to Offshore Substations (OSSs), number and location of OSSs, and interconnection between OSSs and Onshore Connection Points (OCPs). A comparison among different methods is performed, taking into consideration the main engineering constraints. Global optimization, specifically, Binary Programming (BIP) or Mixed Integer Linear Programming (MILP), is envisaged as the best way to tackle this topic. The full combinatorial problem is found to be better addressed following a Top-Bottom approach, combining exact formulations with high level heuristics, or holistically with evolutionary algorithms.

In the present thesis an investigation is performed for the effect of moisture contenton the aging of the solid insulation for transformers that are dynamically loaded. Theinvestigation is based on a theoretical analysis and a model.First, a literature review is conducted on the basics of transformer operation, transformerinsulation and moisture in oil-paper systems. Furthermore, a model is developedbased on moisture equilibrium curves created by Oommen and MIT, moisture diffusionprocesses in oil-paper insulation systems and calculations for the aging of cellulose insulationfrom IEC 60076-7. The model represents an experimental system which is loadedon different load patterns that simulate dynamic loading. The aim of the model is toconclude whether the load patterns will cause the paper to age differently dependingon the frequency that the moisture migration phenomenon between paper and oil occurs.The result of the modeling part is that the aging process is affected by the load pattern,and that the higher the frequency the moisture migration phenomenon occurs within aloading cycle, the larger the impact on insulation degradation. This difference, though,is too small to be measured experimentally in terms of DP and it is suggested thatdifferent load patterns are used in the experiment than those used in the model, whichwill amplify the effect of moisture migration even further.Finally, experimental work is conducted in the thesis, which focuses on implementingthe LabVIEW design from previous work into hardware, debugging the system andpreparing the experimental set-up on practical matters that occurred in the lab. Somefinal work is required before the experiment is able to run, such as preparation of theexperimental units., I detta examensarbete undersöks effekten av fuktinnehåll på åldring av fast isolationsmateriali transformatorer med dynamisk last. Arbetet är baserat på en teoretisk analysoch en modell.Först genomförs en litteraturstudie på grundläggande transformatorfunktion, transformatorisolationoch fukt i oljeimpregnerade papperssystem. Vidare utvecklas en modellbaserad på jämviktskurvor for fukt skapade av Oommen och MIT, fuktdifussionsprocesseri isolationssystem baserade på oljeimpregnerat papper och beräkning av åldringav cellulosaisolation från IEC 60076-7. Modellen representerar ett experimentellt systemsom lastas för att simulera dynamisk last. Målet med modellen är att avgörahuruvida lastprofilen påverkar åldrandet av pappret beroende på frekvensen av fuktmigrationenmellan papper och olja.Resultatet av modelleringen är att åldrandet påverkas av lastprofilen och desto oftarefuktmigrationen sker inom en lastcykel, desto större är effekten på isolationsdegraderingen.Skillnaden är dock för liten att mäta experimentellt med avseende på DP och andralastprofiler föreslås i framtida experiment, för att förstärka effekten av fuktmigration.Slutligen utförs experimentellt arbete som fokuserar på implementation av LabVIEWdesignenfrån tidigare arbete i hårdvara, felsökning av systemet samt förberedelse av denexperimentella installationen för praktiska bekymmer som uppstått i laboratoriemiljön.En liten mängd arbete återstår före experimentet kan utföras, såsom förberedelse av deexperimentella enheterna.

The electric power system is being modernized to enable sustainable energy. This chapter presents analyses of different new technologies and solutions for such modernized power systems. Analyses presented include the integration of wind and solar power, electricity consumption, dynamic rating, and energy storage. The main contribution is to considerate effects of weather parameters to find synergies. A national smart grid demonstration project at Gotland island in Sweden has been used as the case study. Results show how the power systems can handle more electricity consumption and generation. The study shows new technology solutions that are beneficial for resource-efficient electricity grids. The case study results show that, most of the time, the energy storage will be unused, but that it can be used to increase the system reliability during that time., QC 20210927

In the present thesis an investigation is performed for the effect of moisture contenton the aging of the solid insulation for transformers that are dynamically loaded. Theinvestigation is based on a theoretical analysis and a model.First, a literature review is conducted on the basics of transformer operation, transformerinsulation and moisture in oil-paper systems. Furthermore, a model is developedbased on moisture equilibrium curves created by Oommen and MIT, moisture diffusionprocesses in oil-paper insulation systems and calculations for the aging of cellulose insulationfrom IEC 60076-7. The model represents an experimental system which is loadedon different load patterns that simulate dynamic loading. The aim of the model is toconclude whether the load patterns will cause the paper to age differently dependingon the frequency that the moisture migration phenomenon between paper and oil occurs.The result of the modeling part is that the aging process is affected by the load pattern,and that the higher the frequency the moisture migration phenomenon occurs within aloading cycle, the larger the impact on insulation degradation. This difference, though,is too small to be measured experimentally in terms of DP and it is suggested thatdifferent load patterns are used in the experiment than those used in the model, whichwill amplify the effect of moisture migration even further.Finally, experimental work is conducted in the thesis, which focuses on implementingthe LabVIEW design from previous work into hardware, debugging the system andpreparing the experimental set-up on practical matters that occurred in the lab. Somefinal work is required before the experiment is able to run, such as preparation of theexperimental units., I detta examensarbete undersöks effekten av fuktinnehåll på åldring av fast isolationsmateriali transformatorer med dynamisk last. Arbetet är baserat på en teoretisk analysoch en modell.Först genomförs en litteraturstudie på grundläggande transformatorfunktion, transformatorisolationoch fukt i oljeimpregnerade papperssystem. Vidare utvecklas en modellbaserad på jämviktskurvor for fukt skapade av Oommen och MIT, fuktdifussionsprocesseri isolationssystem baserade på oljeimpregnerat papper och beräkning av åldringav cellulosaisolation från IEC 60076-7. Modellen representerar ett experimentellt systemsom lastas för att simulera dynamisk last. Målet med modellen är att avgörahuruvida lastprofilen påverkar åldrandet av pappret beroende på frekvensen av fuktmigrationenmellan papper och olja.Resultatet av modelleringen är att åldrandet påverkas av lastprofilen och desto oftarefuktmigrationen sker inom en lastcykel, desto större är effekten på isolationsdegraderingen.Skillnaden är dock för liten att mäta experimentellt med avseende på DP och andralastprofiler föreslås i framtida experiment, för att förstärka effekten av fuktmigration.Slutligen utförs experimentellt arbete som fokuserar på implementation av LabVIEWdesignenfrån tidigare arbete i hårdvara, felsökning av systemet samt förberedelse av denexperimentella installationen för praktiska bekymmer som uppstått i laboratoriemiljön.En liten mängd arbete återstår före experimentet kan utföras, såsom förberedelse av deexperimentella enheterna.

Power system components usually have standard static ratings that determine the load constraints. Load constraints are designed for extreme conditions and are one of the reasons, why power systems do not use all of their potential transmission capacity. In the 21st century, efficiency and the cost of energy production and distribution have become a very popular topic, because the energy production and its transmission cost has a direct influence on sustainability. Dynamic Rating is a smart grid application, which allows using more of the system capacity by monitoring system conditions. This paper presents a literature review on the topic of Dynamic Rating. We focus on Dynamic Rating of overhead lines. Overhead lines are of great interest for Dynamic Rating applications, because of their high cost and high potential for further improvement. Different tools for analysis of real time data and ways of application of Dynamic Rating to the power system are taken into consideration., QC 20170629, Dynamic Rating for Wind Power

Power system components usually have standard static ratings that determine the load constraints. Load constraints are designed for extreme conditions and are one of the reasons, why power systems do not use all of their potential transmission capacity. In the 21st century, efficiency and the cost of energy production and distribution have become a very popular topic, because the energy production and its transmission cost has a direct influence on sustainability. Dynamic Rating is a smart grid application, which allows using more of the system capacity by monitoring system conditions. This paper presents a literature review on the topic of Dynamic Rating. We focus on Dynamic Rating of overhead lines. Overhead lines are of great interest for Dynamic Rating applications, because of their high cost and high potential for further improvement. Different tools for analysis of real time data and ways of application of Dynamic Rating to the power system are taken into consideration., QC 20170629, Dynamic Rating for Wind Power

In this project dynamic thermal rating for transformers and its effect on transformer reliability are investigated. A literature review is done on different thermal models used for this purpose and at the end differential equations model from IEC 60076-7 and bottom oil model from IEEE C57.91-1995 standard are selected to calculate hot spot temperature. A wind farm connected transformer is selected to implement the models. This transformer belongs to Ellevio AB and manufactured by ABB AB. Load data are gathered for every 5 minutes during 2016. Loss of life of transformer is calculated and it is concluded that by considering this factor, the transformer is overdesigned. The optimum size of transformer by utilizing dynamic rating is selected which results in a reduction in investment cost. This method can be used to select the appropriate size oft ransformer by taking advantages of ambient temperature variations and overload the transformer beyond nameplate ratings without exceeding transformer temperature limitations. Moreover, the risk of overloading the transformer at any time during 2016 is calculated. The risk of overloading is quantified as loss of life of transformer. It is shown that this risk is a function of ambient temperature and the duration of overloading. Finally, an economic analysis is done to demonstrate economic benefit of expanding wind farm by overloading the existing transformer by reducing the transformer life expectancy while keeping it in a safe limit., I detta projekt undersoks dynamisk varmeklassicering for transformatorer ochdess eekt pa transformatorns tillforlitlighet. En litteraturoversikt gors pa olikatermiska modeller som anvands for detta andamal och i slutet av dierentialekvationsmodellenfran IEC 60076-7 och bottenoljemodellen fran IEEE C57.91-1995 standard valjes for att berakna varmpunktstemperatur. En transformatormed vindkraftpark valjs for att genomfora modellerna. Denna transformatortillhor Ellevio AB och tillverkas av ABB AB. Lastdata samlas in for var 5: eminut under 2016. Transformatorns livslangd beraknas och det slutsatsen atttransformatorn ar overdesignad med hansyn till denna faktor. Den optimalastorleken pa transformatorn genom att anvanda dynamisk rating valjs vilket resulterari en minskning av investeringskostnaden. Denna metod kan anvandasfor att valja lamplig storlek for transformatorn genom att dra fordel av omgivandetemperaturvariationer och overbelasta transformatorn bortom markskyltarutan att overskrida transformatortemperaturbegransningar. Dessutomberaknas risken for overbelastning av transformatorn nar som helst under 2016.Risken for overbelastning kvantieras som forlust av livslangd for transformatorn.Det visas att denna risk ar en funktion av omgivande temperatur ochvaraktigheten av overbelastning. Slutligen gors en ekonomisk analys for attvisa ekonomisk nytta av att expandera vindkraftparken genom att overbelastaden bentliga transformatorn genom att minska transformatorens livslangd samtidigtsom den halls i en saker grans.

It is anticipated that with the thrust towards use of clean energy resources such as electric vehicles, future distribution grids will face a steep increase in power demand, forcing the utility operators to invest in enhancing the power delivering capacity of the grid infrastructure. It is identified that the critical 5–20 km medium voltage (MV) underground ac distribution cable link, responsible for bulk power delivery to the inner urban city substation, can benefit the most with capacity and efficiency enhancement, if the existing infrastructure is reused and operated under dc. Quantification of the same is offered in this paper by incorporating all influencing factors like voltage regulation, dc voltage rating enhancement, capacitive leakage currents, skin and magnetic proximity effect, thermal proximity effect and load power factor. Results are presented for three different ac and dc system topologies for varying cable lengths and conductor cross-sections. The computed system efficiency is enhanced with use of modular multilevel converters that have lower losses due to lower switching frequency. A justified expectation of 50–60% capacity gains is proved along with a generalized insight on its variations that can be extrapolated for different network parameters and configurations. Conditions for achieving payback time of 5 years or lower due to energy savings are identified, while the socio-economic benefits of avoiding digging and installing new cable infrastructure are highlighted. The technical implications of refurbishing cables designed for ac to operate under dc conditions is discussed in terms of imposed electric fields, thermal profile and lifetime. A novel opportunity of temperature dependent dynamic dc voltage rating to achieve additional capacity and efficiency gains is presented., DC systems, Energy conversion & Storage

In this project dynamic thermal rating for transformers and its effect on transformer reliability are investigated. A literature review is done on different thermal models used for this purpose and at the end differential equations model from IEC 60076-7 and bottom oil model from IEEE C57.91-1995 standard are selected to calculate hot spot temperature. A wind farm connected transformer is selected to implement the models. This transformer belongs to Ellevio AB and manufactured by ABB AB. Load data are gathered for every 5 minutes during 2016. Loss of life of transformer is calculated and it is concluded that by considering this factor, the transformer is overdesigned. The optimum size of transformer by utilizing dynamic rating is selected which results in a reduction in investment cost. This method can be used to select the appropriate size oft ransformer by taking advantages of ambient temperature variations and overload the transformer beyond nameplate ratings without exceeding transformer temperature limitations. Moreover, the risk of overloading the transformer at any time during 2016 is calculated. The risk of overloading is quantified as loss of life of transformer. It is shown that this risk is a function of ambient temperature and the duration of overloading. Finally, an economic analysis is done to demonstrate economic benefit of expanding wind farm by overloading the existing transformer by reducing the transformer life expectancy while keeping it in a safe limit., I detta projekt undersoks dynamisk varmeklassicering for transformatorer ochdess eekt pa transformatorns tillforlitlighet. En litteraturoversikt gors pa olikatermiska modeller som anvands for detta andamal och i slutet av dierentialekvationsmodellenfran IEC 60076-7 och bottenoljemodellen fran IEEE C57.91-1995 standard valjes for att berakna varmpunktstemperatur. En transformatormed vindkraftpark valjs for att genomfora modellerna. Denna transformatortillhor Ellevio AB och tillverkas av ABB AB. Lastdata samlas in for var 5: eminut under 2016. Transformatorns livslangd beraknas och det slutsatsen atttransformatorn ar overdesignad med hansyn till denna faktor. Den optimalastorleken pa transformatorn genom att anvanda dynamisk rating valjs vilket resulterari en minskning av investeringskostnaden. Denna metod kan anvandasfor att valja lamplig storlek for transformatorn genom att dra fordel av omgivandetemperaturvariationer och overbelasta transformatorn bortom markskyltarutan att overskrida transformatortemperaturbegransningar. Dessutomberaknas risken for overbelastning av transformatorn nar som helst under 2016.Risken for overbelastning kvantieras som forlust av livslangd for transformatorn.Det visas att denna risk ar en funktion av omgivande temperatur ochvaraktigheten av overbelastning. Slutligen gors en ekonomisk analys for attvisa ekonomisk nytta av att expandera vindkraftparken genom att overbelastaden bentliga transformatorn genom att minska transformatorens livslangd samtidigtsom den halls i en saker grans.

It is anticipated that with the thrust towards use of clean energy resources such as electric vehicles, future distribution grids will face a steep increase in power demand, forcing the utility operators to invest in enhancing the power delivering capacity of the grid infrastructure. It is identified that the critical 5–20 km medium voltage (MV) underground ac distribution cable link, responsible for bulk power delivery to the inner urban city substation, can benefit the most with capacity and efficiency enhancement, if the existing infrastructure is reused and operated under dc. Quantification of the same is offered in this paper by incorporating all influencing factors like voltage regulation, dc voltage rating enhancement, capacitive leakage currents, skin and magnetic proximity effect, thermal proximity effect and load power factor. Results are presented for three different ac and dc system topologies for varying cable lengths and conductor cross-sections. The computed system efficiency is enhanced with use of modular multilevel converters that have lower losses due to lower switching frequency. A justified expectation of 50–60% capacity gains is proved along with a generalized insight on its variations that can be extrapolated for different network parameters and configurations. Conditions for achieving payback time of 5 years or lower due to energy savings are identified, while the socio-economic benefits of avoiding digging and installing new cable infrastructure are highlighted. The technical implications of refurbishing cables designed for ac to operate under dc conditions is discussed in terms of imposed electric fields, thermal profile and lifetime. A novel opportunity of temperature dependent dynamic dc voltage rating to achieve additional capacity and efficiency gains is presented., DC systems, Energy conversion & Storage

Power system components usually have standard static ratings that determine the load constraints. Load constraints are designed for extreme conditions and are one of the reasons, why power systems do not use all of their potential transmission capacity. In the 21st century, efficiency and the cost of energy production and distribution have become a very popular topic, because the energy production and its transmission cost has a direct influence on sustainability. Dynamic Rating is a smart grid application, which allows using more of the system capacity by monitoring system conditions. This paper presents a literature review on the topic of Dynamic Rating. We focus on Dynamic Rating of overhead lines. Overhead lines are of great interest for Dynamic Rating applications, because of their high cost and high potential for further improvement. Different tools for analysis of real time data and ways of application of Dynamic Rating to the power system are taken into consideration., QC 20170629, Dynamic Rating for Wind Power

Power system components usually have standard static ratings that determine the load constraints. Load constraints are designed for extreme conditions and are one of the reasons, why power systems do not use all of their potential transmission capacity. In the 21st century, efficiency and the cost of energy production and distribution have become a very popular topic, because the energy production and its transmission cost has a direct influence on sustainability. Dynamic Rating is a smart grid application, which allows using more of the system capacity by monitoring system conditions. This paper presents a literature review on the topic of Dynamic Rating. We focus on Dynamic Rating of overhead lines. Overhead lines are of great interest for Dynamic Rating applications, because of their high cost and high potential for further improvement. Different tools for analysis of real time data and ways of application of Dynamic Rating to the power system are taken into consideration., QC 20170629, Dynamic Rating for Wind Power

Power system components usually have standard static ratings that determine the load constraints. Load constraints are designed for extreme conditions and are one of the reasons, why power systems do not use all of their potential transmission capacity. In the 21st century, efficiency and the cost of energy production and distribution have become a very popular topic, because the energy production and its transmission cost has a direct influence on sustainability. Dynamic Rating is a smart grid application, which allows using more of the system capacity by monitoring system conditions. This paper presents a literature review on the topic of Dynamic Rating. We focus on Dynamic Rating of overhead lines. Overhead lines are of great interest for Dynamic Rating applications, because of their high cost and high potential for further improvement. Different tools for analysis of real time data and ways of application of Dynamic Rating to the power system are taken into consideration., QC 20170629, Dynamic Rating for Wind Power

This paper presents results from a study on the impact of smart grid solutions, which includes development of a generic framework for power system analyses. The study has been performed as one of several independent studies, part of a national governmental task on smart grid in Sweden. A large amount of weather data, along with electricity consumption and wind power generation data, have been analyzed. Achieved results from these initial analyses can be used as reference material and have also been used within case studies presented. The proposed framework is flexible and numerous combinations of scenarios are possible to define. Integration of wind and solar power, analyses of transfer limits using static or dynamic rating and energy storage can be considered as well as weather effects. Results show how power systems can handle more electricity consumption and generation. The study shows that Smart Grid solutions are beneficial for resource efficient electricity grids. Moreover, different risk levels with respect to increased load can be included. Case study results show that energy storages most of the time will be unused, but that they can be used to increase the system reliability., QC 20170206

This paper presents results from a study on the impact of smart grid solutions, which includes development of a generic framework for power system analyses. The study has been performed as one of several independent studies, part of a national governmental task on smart grid in Sweden. A large amount of weather data, along with electricity consumption and wind power generation data, have been analyzed. Achieved results from these initial analyses can be used as reference material and have also been used within case studies presented. The proposed framework is flexible and numerous combinations of scenarios are possible to define. Integration of wind and solar power, analyses of transfer limits using static or dynamic rating and energy storage can be considered as well as weather effects. Results show how power systems can handle more electricity consumption and generation. The study shows that Smart Grid solutions are beneficial for resource efficient electricity grids. Moreover, different risk levels with respect to increased load can be included. Case study results show that energy storages most of the time will be unused, but that they can be used to increase the system reliability., QC 20170206

This paper presents results from a study on the impact of smart grid solutions, which includes development of a generic framework for power system analyses. The study has been performed as one of several independent studies, part of a national governmental task on smart grid in Sweden. A large amount of weather data, along with electricity consumption and wind power generation data, have been analyzed. Achieved results from these initial analyses can be used as reference material and have also been used within case studies presented. The proposed framework is flexible and numerous combinations of scenarios are possible to define. Integration of wind and solar power, analyses of transfer limits using static or dynamic rating and energy storage can be considered as well as weather effects. Results show how power systems can handle more electricity consumption and generation. The study shows that Smart Grid solutions are beneficial for resource efficient electricity grids. Moreover, different risk levels with respect to increased load can be included. Case study results show that energy storages most of the time will be unused, but that they can be used to increase the system reliability., QC 20170206

This paper presents results from a study on the impact of smart grid solutions, which includes development of a generic framework for power system analyses. The study has been performed as one of several independent studies, part of a national governmental task on smart grid in Sweden. A large amount of weather data, along with electricity consumption and wind power generation data, have been analyzed. Achieved results from these initial analyses can be used as reference material and have also been used within case studies presented. The proposed framework is flexible and numerous combinations of scenarios are possible to define. Integration of wind and solar power, analyses of transfer limits using static or dynamic rating and energy storage can be considered as well as weather effects. Results show how power systems can handle more electricity consumption and generation. The study shows that Smart Grid solutions are beneficial for resource efficient electricity grids. Moreover, different risk levels with respect to increased load can be included. Case study results show that energy storages most of the time will be unused, but that they can be used to increase the system reliability., QC 20170206

This paper presents results from a study on the impact of smart grid solutions, which includes development of a generic framework for power system analyses. The study has been performed as one of several independent studies, part of a national governmental task on smart grid in Sweden. A large amount of weather data, along with electricity consumption and wind power generation data, have been analyzed. Achieved results from these initial analyses can be used as reference material and have also been used within case studies presented. The proposed framework is flexible and numerous combinations of scenarios are possible to define. Integration of wind and solar power, analyses of transfer limits using static or dynamic rating and energy storage can be considered as well as weather effects. Results show how power systems can handle more electricity consumption and generation. The study shows that Smart Grid solutions are beneficial for resource efficient electricity grids. Moreover, different risk levels with respect to increased load can be included. Case study results show that energy storages most of the time will be unused, but that they can be used to increase the system reliability., QC 20170206

The concept of dynamic rating (DR) implies that the capacity of a component varies dynamically as a function of external parameters, while the rating traditionally is based on the worst-case. The value of DR thus lies in utilizing existing equipment to a greater extent. By implementing DR and correlating the new ratings with wind power generation, more generation can be implemented. The aim is hence to facilitate connection of renewable electricity production. This paper provides two main contributions: 1) a general dynamic line rating (DLR) calculation model on overhead lines; and 2) an economic optimization simulation model regarding wind power integration comparing DLR with more traditional approaches. These models can both be implemented together, but also separately. The DLR calculation model is easy to use by companies in daily operation where the dynamic line capacity is calculated as a function of static line capacity, wind speed, and ambient temperature. The DLR calculation model is furthermore compared with more comprehensive calculations that validate that the model is accurate enough. This paper also provides an application study where both proposed models are exemplified together and evaluated. Results from this study conclude that it is a significant economic potential of implementing DR within wind power integration., QC 20140902

The concept of dynamic rating (DR) implies that the capacity of a component varies dynamically as a function of external parameters, while the rating traditionally is based on the worst-case. The value of DR thus lies in utilizing existing equipment to a greater extent. By implementing DR and correlating the new ratings with wind power generation, more generation can be implemented. The aim is hence to facilitate connection of renewable electricity production. This paper provides two main contributions: 1) a general dynamic line rating (DLR) calculation model on overhead lines; and 2) an economic optimization simulation model regarding wind power integration comparing DLR with more traditional approaches. These models can both be implemented together, but also separately. The DLR calculation model is easy to use by companies in daily operation where the dynamic line capacity is calculated as a function of static line capacity, wind speed, and ambient temperature. The DLR calculation model is furthermore compared with more comprehensive calculations that validate that the model is accurate enough. This paper also provides an application study where both proposed models are exemplified together and evaluated. Results from this study conclude that it is a significant economic potential of implementing DR within wind power integration., QC 20140902

The concept of dynamic rating (DR) implies that the capacity of a component varies dynamically as a function of external parameters, while the rating traditionally is based on the worst-case. The value of DR thus lies in utilizing existing equipment to a greater extent. By implementing DR and correlating the new ratings with wind power generation, more generation can be implemented. The aim is hence to facilitate connection of renewable electricity production. This paper provides two main contributions: 1) a general dynamic line rating (DLR) calculation model on overhead lines; and 2) an economic optimization simulation model regarding wind power integration comparing DLR with more traditional approaches. These models can both be implemented together, but also separately. The DLR calculation model is easy to use by companies in daily operation where the dynamic line capacity is calculated as a function of static line capacity, wind speed, and ambient temperature. The DLR calculation model is furthermore compared with more comprehensive calculations that validate that the model is accurate enough. This paper also provides an application study where both proposed models are exemplified together and evaluated. Results from this study conclude that it is a significant economic potential of implementing DR within wind power integration., QC 20140902

The concept of dynamic rating (DR) implies that the capacity of a component varies dynamically as a function of external parameters, while the rating traditionally is based on the worst-case. The value of DR thus lies in utilizing existing equipment to a greater extent. By implementing DR and correlating the new ratings with wind power generation, more generation can be implemented. The aim is hence to facilitate connection of renewable electricity production. This paper provides two main contributions: 1) a general dynamic line rating (DLR) calculation model on overhead lines; and 2) an economic optimization simulation model regarding wind power integration comparing DLR with more traditional approaches. These models can both be implemented together, but also separately. The DLR calculation model is easy to use by companies in daily operation where the dynamic line capacity is calculated as a function of static line capacity, wind speed, and ambient temperature. The DLR calculation model is furthermore compared with more comprehensive calculations that validate that the model is accurate enough. This paper also provides an application study where both proposed models are exemplified together and evaluated. Results from this study conclude that it is a significant economic potential of implementing DR within wind power integration., QC 20140902

The concept of dynamic rating (DR) implies that the capacity of a component varies dynamically as a function of external parameters, while the rating traditionally is based on the worst-case. The value of DR thus lies in utilizing existing equipment to a greater extent. By implementing DR and correlating the new ratings with wind power generation, more generation can be implemented. The aim is hence to facilitate connection of renewable electricity production. This paper provides two main contributions: 1) a general dynamic line rating (DLR) calculation model on overhead lines; and 2) an economic optimization simulation model regarding wind power integration comparing DLR with more traditional approaches. These models can both be implemented together, but also separately. The DLR calculation model is easy to use by companies in daily operation where the dynamic line capacity is calculated as a function of static line capacity, wind speed, and ambient temperature. The DLR calculation model is furthermore compared with more comprehensive calculations that validate that the model is accurate enough. This paper also provides an application study where both proposed models are exemplified together and evaluated. Results from this study conclude that it is a significant economic potential of implementing DR within wind power integration., QC 20140902

Power system owners are facing major challenges, for example with changed electricity consumption and production patterns; more distributed generation and increased demand of cost efficiency while maintaining high reliability. The concept of dynamic rating can act as a part solution and implies that the capacity of a component is dynamically varying as a function of external parameters such as weather and load history. This hence implies that a component can be better utilized. This can have both direct economic benefits for the utility, but also benefits for the society and the environment by lower tariff levels, faster and cheaper connection of local environmentally friendly electricity production and less climate impact associated with component production and installation. This paper gives a brief introduction to the concept of dynamic rating applied to power systems. Furthermore, results and conclusions from two workshops during 2013 are summarized, where representatives from Vattenfall and Fortum (distribution system operators), ABB (producer and developer that work with dynamic rating solutions), Swedish national grid and several persons from the academia contributed. This was complemented by interviews with the involved companies. The result is a mapping of knowledge, research, development interests, current situation and future visions. All parties show a great interest and see potential, but there are also challenges to be solved., QC 20140806

Power system owners are facing major challenges with changed electricity consumption and production patterns; more distributed generation and increased demand of cost efficiency while maintaining high reliability. Today, the capacity of power components often is set with static limits based on simulations of worst case scenarios. This leads to a discrepancy between the actually-available capacity and the rating itself which unfortunately is left unused. The approach of dynamic rating implies that the capacity of a component is dynamically varying as a function of external parameters such as weather, load history and diagnostic indicators. Svenska kraftnät (Swedish national grid) has installed temperature sensors with the purpose of developing condition monitoring methods in another research project. Within this project, the same infrastructure can perhaps be used to also evaluate dynamic rating algorithms of power lines or to develop new algorithms regarding e.g. disconnectors. Also the thermal modelling in that project can be reused. This paper hence exemplifies the possibility to get more applications without additional costly and complicated investments. The aim of the paper is hence to show on future research possibilities and bring ideas to discussion., QC 20140922

Power system owners are facing major challenges, for example with changed electricity consumption and production patterns; more distributed generation and increased demand of cost efficiency while maintaining high reliability. The concept of dynamic rating can act as a part solution and implies that the capacity of a component is dynamically varying as a function of external parameters such as weather and load history. This hence implies that a component can be better utilized. This can have both direct economic benefits for the utility, but also benefits for the society and the environment by lower tariff levels, faster and cheaper connection of local environmentally friendly electricity production and less climate impact associated with component production and installation. This paper gives a brief introduction to the concept of dynamic rating applied to power systems. Furthermore, results and conclusions from two workshops during 2013 are summarized, where representatives from Vattenfall and Fortum (distribution system operators), ABB (producer and developer that work with dynamic rating solutions), Swedish national grid and several persons from the academia contributed. This was complemented by interviews with the involved companies. The result is a mapping of knowledge, research, development interests, current situation and future visions. All parties show a great interest and see potential, but there are also challenges to be solved., QC 20140806

Power system owners are facing major challenges with changed electricity consumption and production patterns; more distributed generation and increased demand of cost efficiency while maintaining high reliability. Today, the capacity of power components often is set with static limits based on simulations of worst case scenarios. This leads to a discrepancy between the actually-available capacity and the rating itself which unfortunately is left unused. The approach of dynamic rating implies that the capacity of a component is dynamically varying as a function of external parameters such as weather, load history and diagnostic indicators. Svenska kraftnät (Swedish national grid) has installed temperature sensors with the purpose of developing condition monitoring methods in another research project. Within this project, the same infrastructure can perhaps be used to also evaluate dynamic rating algorithms of power lines or to develop new algorithms regarding e.g. disconnectors. Also the thermal modelling in that project can be reused. This paper hence exemplifies the possibility to get more applications without additional costly and complicated investments. The aim of the paper is hence to show on future research possibilities and bring ideas to discussion., QC 20140922

Power system owners are facing major challenges, for example with changed electricity consumption and production patterns; more distributed generation and increased demand of cost efficiency while maintaining high reliability. The concept of dynamic rating can act as a part solution and implies that the capacity of a component is dynamically varying as a function of external parameters such as weather and load history. This hence implies that a component can be better utilized. This can have both direct economic benefits for the utility, but also benefits for the society and the environment by lower tariff levels, faster and cheaper connection of local environmentally friendly electricity production and less climate impact associated with component production and installation. This paper gives a brief introduction to the concept of dynamic rating applied to power systems. Furthermore, results and conclusions from two workshops during 2013 are summarized, where representatives from Vattenfall and Fortum (distribution system operators), ABB (producer and developer that work with dynamic rating solutions), Swedish national grid and several persons from the academia contributed. This was complemented by interviews with the involved companies. The result is a mapping of knowledge, research, development interests, current situation and future visions. All parties show a great interest and see potential, but there are also challenges to be solved., QC 20140806

Power system owners are facing major challenges with changed electricity consumption and production patterns; more distributed generation and increased demand of cost efficiency while maintaining high reliability. Today, the capacity of power components often is set with static limits based on simulations of worst case scenarios. This leads to a discrepancy between the actually-available capacity and the rating itself which unfortunately is left unused. The approach of dynamic rating implies that the capacity of a component is dynamically varying as a function of external parameters such as weather, load history and diagnostic indicators. Svenska kraftnät (Swedish national grid) has installed temperature sensors with the purpose of developing condition monitoring methods in another research project. Within this project, the same infrastructure can perhaps be used to also evaluate dynamic rating algorithms of power lines or to develop new algorithms regarding e.g. disconnectors. Also the thermal modelling in that project can be reused. This paper hence exemplifies the possibility to get more applications without additional costly and complicated investments. The aim of the paper is hence to show on future research possibilities and bring ideas to discussion., QC 20140922

Power system owners are facing major challenges, for example with changed electricity consumption and production patterns; more distributed generation and increased demand of cost efficiency while maintaining high reliability. The concept of dynamic rating can act as a part solution and implies that the capacity of a component is dynamically varying as a function of external parameters such as weather and load history. This hence implies that a component can be better utilized. This can have both direct economic benefits for the utility, but also benefits for the society and the environment by lower tariff levels, faster and cheaper connection of local environmentally friendly electricity production and less climate impact associated with component production and installation. This paper gives a brief introduction to the concept of dynamic rating applied to power systems. Furthermore, results and conclusions from two workshops during 2013 are summarized, where representatives from Vattenfall and Fortum (distribution system operators), ABB (producer and developer that work with dynamic rating solutions), Swedish national grid and several persons from the academia contributed. This was complemented by interviews with the involved companies. The result is a mapping of knowledge, research, development interests, current situation and future visions. All parties show a great interest and see potential, but there are also challenges to be solved., QC 20140806

Power system owners are facing major challenges with changed electricity consumption and production patterns; more distributed generation and increased demand of cost efficiency while maintaining high reliability. Today, the capacity of power components often is set with static limits based on simulations of worst case scenarios. This leads to a discrepancy between the actually-available capacity and the rating itself which unfortunately is left unused. The approach of dynamic rating implies that the capacity of a component is dynamically varying as a function of external parameters such as weather, load history and diagnostic indicators. Svenska kraftnät (Swedish national grid) has installed temperature sensors with the purpose of developing condition monitoring methods in another research project. Within this project, the same infrastructure can perhaps be used to also evaluate dynamic rating algorithms of power lines or to develop new algorithms regarding e.g. disconnectors. Also the thermal modelling in that project can be reused. This paper hence exemplifies the possibility to get more applications without additional costly and complicated investments. The aim of the paper is hence to show on future research possibilities and bring ideas to discussion., QC 20140922

Power system owners are facing major challenges, for example with changed electricity consumption and production patterns; more distributed generation and increased demand of cost efficiency while maintaining high reliability. The concept of dynamic rating can act as a part solution and implies that the capacity of a component is dynamically varying as a function of external parameters such as weather and load history. This hence implies that a component can be better utilized. This can have both direct economic benefits for the utility, but also benefits for the society and the environment by lower tariff levels, faster and cheaper connection of local environmentally friendly electricity production and less climate impact associated with component production and installation. This paper gives a brief introduction to the concept of dynamic rating applied to power systems. Furthermore, results and conclusions from two workshops during 2013 are summarized, where representatives from Vattenfall and Fortum (distribution system operators), ABB (producer and developer that work with dynamic rating solutions), Swedish national grid and several persons from the academia contributed. This was complemented by interviews with the involved companies. The result is a mapping of knowledge, research, development interests, current situation and future visions. All parties show a great interest and see potential, but there are also challenges to be solved., QC 20140806

Power system owners are facing major challenges with changed electricity consumption and production patterns; more distributed generation and increased demand of cost efficiency while maintaining high reliability. Today, the capacity of power components often is set with static limits based on simulations of worst case scenarios. This leads to a discrepancy between the actually-available capacity and the rating itself which unfortunately is left unused. The approach of dynamic rating implies that the capacity of a component is dynamically varying as a function of external parameters such as weather, load history and diagnostic indicators. Svenska kraftnät (Swedish national grid) has installed temperature sensors with the purpose of developing condition monitoring methods in another research project. Within this project, the same infrastructure can perhaps be used to also evaluate dynamic rating algorithms of power lines or to develop new algorithms regarding e.g. disconnectors. Also the thermal modelling in that project can be reused. This paper hence exemplifies the possibility to get more applications without additional costly and complicated investments. The aim of the paper is hence to show on future research possibilities and bring ideas to discussion., QC 20140922

As the demand for energy increases, as well as the demand for renewable energy, Vattenfall, as network owner, receives many requests to connect new wind power to the grid. The limiting factor for how much wind power that can be connected to the grid is in this case the maximum current capacity of the overhead lines that is based on a line temperature limit. The temperature limit is set to ensure a safety distance between the lines and the ground. This master thesis project is a part of a research project at Vattenfall Research and Development that is examining the possibilities of increasing the allowed current on overhead lines in order to be able to connect more wind power to the existing network. Measured data from two overhead lines in southern Sweden is analyzed and the internal relations between the measured parameters are examined. The measured parameters are overhead line sag, line temperature, ambient temperature, solar radiation, wind speed and line current. The results indicate that there is a big load margin that could be utilized to increase the maximum current as long as further work could show that low winds at line height correlates with low wind at nacelle height. The results show that the sag versus line temperature is approximately linear within the measured temperature range. This means that a real-time-monitoring system measuring the line temperature should give adequate knowledge of the line position to ensure the safety distance. A model for the line temperature as a function of insolation, current, ambient temperature and wind speed has been estimated for one of the lines. Simulations show that a sudden increase in current at a worst-case scenario would give the operators about ten minutes to react before the line reaches the temperature limit.

As the demand for energy increases, as well as the demand for renewable energy, Vattenfall, as network owner, receives many requests to connect new wind power to the grid. The limiting factor for how much wind power that can be connected to the grid is in this case the maximum current capacity of the overhead lines that is based on a line temperature limit. The temperature limit is set to ensure a safety distance between the lines and the ground. This master thesis project is a part of a research project at Vattenfall Research and Development that is examining the possibilities of increasing the allowed current on overhead lines in order to be able to connect more wind power to the existing network. Measured data from two overhead lines in southern Sweden is analyzed and the internal relations between the measured parameters are examined. The measured parameters are overhead line sag, line temperature, ambient temperature, solar radiation, wind speed and line current. The results indicate that there is a big load margin that could be utilized to increase the maximum current as long as further work could show that low winds at line height correlates with low wind at nacelle height. The results show that the sag versus line temperature is approximately linear within the measured temperature range. This means that a real-time-monitoring system measuring the line temperature should give adequate knowledge of the line position to ensure the safety distance. A model for the line temperature as a function of insolation, current, ambient temperature and wind speed has been estimated for one of the lines. Simulations show that a sudden increase in current at a worst-case scenario would give the operators about ten minutes to react before the line reaches the temperature limit.

Due to the great complexity of VHDL models that are created today, the amount of processing time required to simulate these models and the amount of labor required to develop these models have become critical issues. The amount of processing time required to simulate a model can be directly influenced by the efficient use of VHDL concepts in creating the model. This dissertation presents an approach to aiding the modeler in the development of more efficient VHDL models. This is done by measuring the simulation efficiency of process-level VHDL behavioral models. Research in the determination of what VHDL constructs and modeling styles are most efficient is presented. The development and use of a tool that parses VHDL behavioral models and reveals the efficiency of the code in the form of a numerical efficiency rating is also presented.