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Electric power systems are experiencing a growing number of electronic loads in the residential sector as modern appliance technology progresses, and it has become increasingly more important to consider the total power factor (PF) of residential communities. This paper provides a survey based on literature and publicly available information of typical appliance PF values and effects at the residential level as well as a discussion on appliance energy use and corresponding operation schedules. A procedure for the calculation of equivalent PF is proposed and exemplified with minutely experimental data at 15-minute and hourly time intervals, which correspond to smart metering and traditional practices, respectively. The application of the proposed equivalent PF procedure in coordination with building energy modeling, may, in principle, be employed to determine PF for entire communities at an aggregated level. The paper includes a proposal to simulate reactive power through an approach that utilizes EnergyPlus, a building energy modeling software. Such simulation capability could facilitate improved planning for compensation implementation both in electric power distribution networks and in individual residences, which offers significant opportunity for energy savings.

In the future, active network management (ANM) and adaptive distributed energy resources (DER) control schemes will be increasingly required to fulfill growing power system resiliency and renewable generation integration needs. As part of future ANM schemes more frequent electricity distribution network topology changes could be utilized to improve the electricity supply reliability. However, these topology changes may require DER control methods and functions adaptation accordingly in order to maintain feasible power quality, voltage level and supply reliability in the distribution network. This paper presents a real-life case study from the needed adaptation of DER control schemes and functions after MV distribution network topology change from normal to back-up connection. The focus in the studied case is on MV network connected wind turbine (WT) control scheme adaptation after the topology change based on real measured data from the WT. In addition, the paper presents also simulations from potential future scenarios with centralized and distributed battery energy storage systems (BESSs) which could be also simultaneously utilized for the provision of local and system-wide services.

This paper describes a terminal for remote control of renewable energy sources powered station for electric vehicles charging. This terminal enables remote control of electric vehicle chargers, smart storage batteries, smart electricity meters, cash registers, as well as, remote control of renewable energy sources and other devices within the station. In this way, stations for electric vehicles charging powered by renewable energy sources, are made more accessible to electric vehicles users, to electricity distribution system operators, to supplier operators, to tax administration operators, and finally to users and owners of station for electric vehicles charging. In this paper, the realization of hardware and software of such terminal has been also described. Its development and commercialization would potentially encourage an increase in the use of electric vehicles powered by energy from renewable sources, which would decrease the level of air pollution as well as the negative effects it brings.

Distribution systems losses are the major losses in electrical power systems. The main objective of this paper is to study the losses in Sudanese electricity distribution company (SEDC) networks. The paper works out a hypothesis that feeding customers’ directory form medium voltage will decrease the overall losses in the SEDC network. The paper began by running a simulating model to study the impact of eliminating the lowvoltage network of AL-Basher city’s losses, NEPLAN program was used to simulate the research problem. Two different models (A, B) were designed for Al-Bashir city network in Red Sea State, specifications and data were taken from Geographical Information System program (GIS); the tow is identical in loads, conductor’s length and total transformers capacities. The simulation result shows that the losses were decreased from 22.58% in case A to 5.46% in case B. These results reveal a very high reduction in losses reached 17.12% when customers were divided into small groups and each group feed by 15 KVA/ 11KV transformers as in model B.

The term "price volatility" is used to describe price fluctuations in asset prices. Prices of basic energy (natural gas, electricity, heating oil) are generally more volatile than prices of other commodities. Volatility indicates a measure of price uncertainty in markets. When volatility rises, firms may delay investment and other decisions or increase their risk management activities such as hedging. The costs associated with such activities tend to increase the costs of supplying and consuming energy. The main goal of this paper is to build a volatility model and demonstrate a mechanism to forecast electricity price volatility using electricity distribution of EMCALI ("Empresses Municipals de Cali") in Colombian electricity market. The objectives of this study are threefold: 1) First we begin our approach by introducing the energy market in Colombia and EMCALI’s role in generation and distribution of electricity. 2) Next we discuss some of the more widely used time series techniques and also show how we can utilize generalized autoregressive conditional heteroscedastic (GARCH) volatility model as a volatility forecasting model for the energy price in Colombia. 3) Finally, we apply this model to estimate the behavior of the electricity price volatility and discuss the results obtained. The paper ends with conclusions.

In this paper, the effect of raising the distribution system voltage level to 0.6 kV and 1 kV on the technical and nontechnical energy losses has been investigated. This investigation has been based on a case study in the Jordanian Electricity Distribution Company (EDCO) network. It presents technical and cost comparison between different distribution networks including different system typologies for the 0.4 kV, 0.6 kV and 1 kV distribution systems. The distribution network of Karak city in Jordan has been modeled using CYME software and updated with the grid data needed to perform the analysis, such as transmission line parameters and lengths; and transformers ratings. The study has been performed, firstly, by analyzing the current situation of the grid with 0.4 kV distribution voltage. Then the grid voltage has been raised to 0.6 kV and 1 kV to reduce the technical and non-technical energy losses. A comparative analysis between the current situation and the proposed two solutions concluded this paper.

Despite the National Grid expecting the number of electric vehicles (EVs) on UK roads to increase to 35 million by 2050 (2019 data), the effect of electric vehicle chargers (EVCs) together with steady-state cable faults on the total harmonic distortion of the LV electricity distribution network (EDN) has not been considered. Therefore, the purpose of this paper is to investigate the effect that increased numbers of EVCs have on the steady-state voltage total harmonic distortion (THDv) of a UK LV EDN under steady-state cable fault arrangements. Using MATLAB simulations, the study analysed the steady-state THDv of a UK suburban residential LV EDN with increased numbers of EVCs under phase-to-phase and open-circuit network conditions. It was found that on the LV EDN studied, phase-to-phase conditions can increase the THDv of the network significantly. Under the test conditions, the LV EDN was found to no longer comply with the Engineering Recommendation G5/4-1. This paper recommends that the number of EVCs connected to LV EDNs should be restricted, or harmonic reducing technology implemented to observe compliance with the G5/4-1. Further analysis should be carried out to verify the simulation and to determine whether the harmonics observed have a noticeable effect on equipment connected to a residential network.

With the proliferation of distributed energy resources and advanced metering, modern electric power distribution systems require more simulation and engineering analysis to ensure that the planning and operation of the evolving feeders are efficient and reliable. Although distribution analytical and operational tools are widely available, their usage by utility engineers has been particularly difficult because of the huge effort required in massaging the data available from their enterprise systems into the unique database requirements for each analytical tool. This paper presents a data modelling and application usage framework for utilities that utilizes the Common Information Model (CIM) to standardize and integrate data directly available from the utility enterprise database. The paper describes this framework’s approach in standardizing a utility’s distribution data and storing it in a large database of high fidelity CIM models which can then be used as input to any analytical tool that can accept data in a CIM structure. This is demonstrated by using this CIM-based integration framework for Avista Corporation to translate data in the CIM structure into a distribution model of GridLAB-D, which is an open source distribution system simulator. The results from GridLAB-D are presented to show that many proprietary distribution analytical and operational tools can be made inter-operable if the utilities adopt such a CIM based data platform as a standard for distribution data.

In 2010, South Africa introduced the Renewable Energy Independent Power Producer Procurement Programme to invigorate low-carbon energy generation using renewable energy resources. Amongst the development of wind and hydro plants; solar photovoltaic plants then took off rapidly. The volume of solar PV plants connected to the grid in 2015 and 2016 was unparalleled. However, the solar PV electric power distribution network is challenged with the presence of unacceptable harmonics and distortion content at the point of common coupling due to the switching action of inverters and operation of non-linear loads. It therefore essential to precisely estimate the resultant increased load losses in order to estimate the hot spot temperature and total losses during service.In order to demonstrate the significance of these challenges, this paper provides a comprehensive harmonic analysis of an oil-filled transformer for the supplied geometrical data and harmonic spectrum of an oil-filled transformer. The load losses are evaluated under fundamental and harmonic conditions. The load losses are classified into I2R and stray losses. The I2R losses can be easily obtained by analytical calculations and also through practical measurement. On one hand, analytical calculation of the stray losses cannot give an optimized estimation and practically their immeasurable. In this paper, a 2D FEM model that is dynamic to any transformer geometrical data is developed to produce a pragmatic loss estimation by using knowledge of the magnetic flux density. Generally, analytical formulations neglect the radial magnetic flux density component. During operation, this component becomes predominant towards the winding ends and cannot be disregarded.

With the development and popularization of electric vehicle (EV), impacts of large-scale of EV charging to the power system have emerged, especially to the distribution systems. Most of the electricity distribution infrastructure was designed before EV is developed, so most of the existing distribution transformers did not consider the load of the EV charging stations. The large-scale un-coordinated charging EVs can cause the overload or damage of the distribution transformers. Therefore this paper developed a real time control system which monitor the load of the distribution transformers in real time. If it is overloaded, the control system then sends a control command to the charging piles to reduce the output power of the charging piles in order to reduce the overload of the distribution transformers. The coordinated control strategy for electric vehicle charging piles is discussed in the paper. The control strategy under various operation conditions are analyzed. Based on the control strategy, the power output of the charging pile is optimized according to the real-time operation data such as the distribution transformer load, the load of each charging pile and the operation status of the charging piles. Finally, the simulation of cases is performed. The results show that the coordinated control strategy is effective in preventing overload of distribution transformers. It is believed that the control system developed can solve the difficulties of building charging station in old districts and in dense urban areas, where the existing distribution transformers have the risk of overloading during peak demand times.

This paper presents the evolution and development trends of the distributed control systems (DCS) implemented in the Electrical Power Systems, highlighting the impact of the modern versus traditional DCS systems. The principles of the modern DCS systems presented in this paper can be found implemented in Romania in the Transmission and Distribution energy sector, implemented by the Romanian Transmission and System Operator CNTEE Transelectrica SA and, as well as the electricity distribution operators like Electrica, EoN and CEZ.

The South African government policy to electrify all customers has placed immense demands on the electricity infrastructure. Several new connected customers in line with these government targets and plans are in networks that are already constrained, with the consequence of violating statutory performance requirements and electrical parameters, such as thermal loading, voltage limits and technical losses. Utilities' solutions to remedy these problems sometimes requires huge investments to upgrade infrastructure and this may take years for implementation. In many instances, short-term solutions are available and feasible. This study investigates Solar Roof-Top PV (RTPV) as a renewable energy resource for reticulation (11/22KV) networks. Currently RTPV is not well documented and guided when considering available Grid codes, Guidelines and Standards. This paper demonstrates that RTPV penetration is more worthwhile to consider than capital strengthening/refurbishment projects. The study demonstrates the supportive role of RTPV to meet electrification demands. With increased penetration of RTPV's on distribution networks, there is a benefit to the feeder tail-end voltages with reduced thermal loading and technical losses in distribution networks. This provides Utilities with the opportunity to electrify more customers and defer capital expenditure, while reducing the carbon footprint. The balance of the paper presents an accurate view of RTPV analysis, attributed to the accuracy of data, by using a practical network topology coupled with its related statistical loading. It further takes into account the associated customer connected at the LV transformers. With the imminent influx of RTPV, the results of this study will assist in equipping the South African Electricity Supply Industry (ESI) for the readiness of RTPV and the influence of RTPV on reticulation networks by quantifying the impacts and expectations for the Electric Power Utility and the customer.

The assurance of a high quality of the voltage that supplies consumers is a first-degree demand for an optimal operation of the public electricity distribution networks (EDNs), being a permanent concern, both for Distribution Network Operators (DNOs) and the final consumers. The paper proposes a new optimal voltage control (OVC) approach in EDN using a hybrid line-drop compensation method based on adaptive On-Load Tap Changer (OLTC) Transformers techniques. The OVC problem is split into two separate subproblem which are simultaneously solved. Thus, the paper newness is the automatic OLTC control technique, which must to maintain the optimal operation voltage value in a “controlled” point considering two parameters: the so-called fictitious voltage and the corresponding imaginary impedance. A particular MATLAB code was applied taking into account the voltage quality parameter for a real medium voltage EDN. The results confirm the robustness of the proposed approach both for OVC through OLTC optimization.

The paper presents the results of the analysis, studies and computer simulation of the series type arc fault discharges, based on the load current deviations, abnormal for the regular processes and normalized current ripples. This method assumes continuous load current monitoring and its comparison with the reference value. There is a possibility that the information on loads state, being uploaded into processor of the Secondary Power Distribution Unit, would be enough for the aircraft electric power distribution systems with preassigned set of loads, being developed. The considered method arouses interest as the least costly. Thus, the main attention is paid to it in the framework of this paper.

In recent years, distributed photovoltaic (PV) systems have witnessed rapid development worldwide. Nevertheless, the diffusion of distributed PV systems in a specific region is still indefinite and hard to predict, which bring uncertainties to the planning and operation of electricity distribution network. This paper investigates the diffusion tendency and forecasting approach of distributed PV systems from macro- and micro-aspects. Macroscopic analysis includes spatial clustering of PV systems and quantitative analysis of PV adoption drivers in the time-dimension. Shanghai, Pudong in China is studied in this paper to offer some insights. Analysis reveals that the capacity and location of PV systems are clustered. These clusters continuously spread to the surrounding with changes of size and location, under the impact of internal and external factors. This indicates that diffusion of PV systems can be simulated by a cellular automation model. For microscopic analysis, a data-driven forecasting approach of PV diffusion is proposed based on cellular automation. Analysis shows that the developing state of PV cells can be forecasted based on multi-source datasets. Besides, statistical distribution of newly installed PV capacity per cell tends to be stable, so that it can also be considered as a predictor of distributed PV systems diffusion.

The market of electric and hybrid vehicles is still small compared to the market of combustion vehicles. However, this is an ever-expanding market. This paper aims to model the increase in electrical vehicles market in Brazil, which could help the electrical demand forecasting for electricity distribution utilities. The System Dynamics and the Bass Diffusion Model are used to represent the proposed system of the electrical vehicle market, first with a qualitative and then with a quantitative model. Three scenarios are simulated to test and validate it. The results show that the methodology used in this paper is adequate to model the system using different nature parameters, such as behavioral, strategic and economic.

Electricity distribution networks across the world are increasingly featured with renewable generation to meet sustainable energy requirements, while there is limited investment in network reinforcement. Hence, it is important to accurately evaluate the renewable hosting capacity of a distribution network to avoid any detrimental effect caused by increased penetration. In this context, this paper proposes a two-stage optimisation-based approach to calculate the maximum renewable hosting capacity of a distribution network without violating any security constraints. The approach is demonstrated using an IEEE 123-node distribution network with detailed simulations, and the results compared with two conventional approaches (experience-based and streamlined approach). The results indicate that the proposed approach can achieve higher hosting capacity as opposed to conventional approaches. In addition, this paper also presents detailed procedures to implement the two conventional approaches.

This paper introduces an approach of local voltage anomaly detection in electric power distribution grid using IEC 61850-9-2 LE Sampled Values (SV) as transmission protocol [1]. The approach was implemented and tested in a real-time simulation unit, where a defined distribution grid provides simulated voltage data. An analysis of transmitted samples on a receiver and computation device according to power quality measurements and their limits due to dynamic behaviour is done. The goal of our proposed anomaly detection is in contrast to previous approaches to detect disturbances caused by cyberattacks on ICS components in distribution grids based on an open communication interface. This paper defines the first part of detection at a local node in a defined grid configuration.

This paper outlines a methodology that will allow to evaluate the performance of the smart grid technologies, as well as to mitigate faults in electric power distribution systems. The proposed method includes the evaluation of the main factors that influence the quality of services. Network topology, availability of protective equipment, maneuvering, telecontrol and traffic in the access routes are evaluated together with the reliability of the power supply, in order to combine the results of these criteria with quality indicators, which will allow mitigating the impacts of the faults and propose more efficient short and medium term investments. The paper will also approach an analysis methodology based on Spatial Decision Support System, Knowledge Discovery in Database Technique and Unsupervised Machine Learning, providing in a practical and easy way the comparison between feeders, substations or even regions that make up a distribution system. A pilot presents a system that illustrates the proposed methodology, with results and preliminary analysis, based on real situations based on historical data from an electrical utility in Northeast of Brazil

The problem of reconfiguration of electric power distribution networks searches a topology for the network that minimizes technical losses (resistive losses). Finding the optimal configurations is a difficult combinatorial optimization problem that has been gaining a new form over the last decade, arising from the introduction of distributed generation along the networks, and of complementary innovations associated to the concept Smart Grids. A previous paper discussed the characteristics and solution alternatives for the problem in scenarios where there is a small set of random sources with significant energy generation compared to the total energy handled by the distribution network. This paper discusses the problem of unveiling the best network configuration for the operation of a radial distribution network when a large number of small intermittent sources inject energy in the network.

This paper investigates network integration of distributed rooftop PV systems on three distribution networks (one residential, one commercial and one industrial) in Cape Town, South Africa. A methodology is developed that can be used to model the technical influence (focusing solely on voltage rise and equipment overload) of randomly distributed solar PV uptake on electrical distribution networks. For the residential- and industrial area, the amount of PV-eligible roof space provides potential PV generation capacity that far exceeds the load requirements of the area. It is shown that allowable PV installations on the residential LV networks vary between 187 kW – 373 kW, and allowable PV penetration levels vary between 82% - 150%. The industrial network has the lowest allowable PV penetration level (31%), whilst the commercial area experiences no limit to the uptake of PV, since there is not enough PV-eligible roof space, and subsequent potential PV generation capacity, to cause network problems. This paper concludes guidelines as to the PV hosting capacity of the sample networks. The results of this paper provide a better understanding to utilities in terms of the technical limits that dictate PV uptake for different types of networks, as well as the corresponding PV penetration levels.

This paper uses the relevant knowledge of complex network theory to analyze the static characteristic parameters such as node degree, node degree distribution, network average length and node tightness of W city rail transit network, electric power distribution network and load network. The importance index of the nodes is analyzed, by taking W city rail transit network and electric power distribution network as the research object of the composite network. At the same time, this paper points out the important nodes in the rail transit network of W city. The energy efficiency coefficient changes of W city rail transit network and rail transit composite network under random attack and deliberate attack mode is simulated, which provides reference for the subsequent protection and planning of relevant departments.

This paper continues to develop the previous paper on Application Data for Electricity Load Forecasting Models by applying the method to the geographic information system (GIS) technology in medium-term energy forecasting for the Metropolitan Electricity Authority (MEA) area of Bangkok, Thailand. This method can be employed to improve the electricity load efficiency of the MEA. The spatial prediction plays a key role in the expansion of the areas of electricity distribution, such as the decision-making regarding investment in new substations and power system planning for maintenance and operations. The results appear to indicate that the prediction of the point density of the MEA areas was proportional to the electricity demand in the MEA areas.

With rapid development towards sustainable smart grids, the future electricity distribution networks should be able to host more and more distributed generation (DG) and enable also higher demand peaks e.g., due to charging of electric vehicles (EVs). Soft Open Point (SOP) is one potential enabling solution, which could provide multiple functionalities for future active network management (ANM) and improve resiliency and flexibility of future electricity distribution networks. The focus in this paper is to design a new control method for SOP inverters in back-to-back (B2B) configuration. This paper proposes an outer autonomous reactive power controller for active voltage level management in an example medium-voltage (MV) distribution network. The developed new SOP control methods are validated with Matlab based simulation results. Results show that developed autonomous SOP control is an effective option for active voltage management in future MV networks.

Aiming at the randomness and volatility of the abandoned wind with high proportion wind power connected to the large power grid, this paper proposed a the entire processes accurate evaluation analysis method with multi-dimensional, multi-period and multi-type, constructed a multi-dimensional analysis system such as electricity, hours, abandonment rate and abandonment ratio, and constructed a multi-period analysis system such as the annual, heating season, monthly and hourly electricity distribution and the corresponding low valley period, it also constructed a multi-type analysis system such as peak shaving abandoned wind and grid structure abandoned wind, which provides a theoretical basis for implementing large-scale abandoned wind consumption. Combined with the actual examples, the abandoned wind analysis system established in this paper has practical significance for mastering the law of abandoning wind and selecting appropriate measures for abandoning wind consumption.

The power grid has to suffer from several power quality issues with the increased penetration of renewable energy resources. These power quality related problems impact both distributor and consumer applications. Actually, there are limited prediction models to identify power quality issues in advance. Furthermore, the traditional methods are practically costly, which makes it challenging to use for prediction and classification of power quality events. The supervised machine learning technique, the subfield of artificial intelligence, explores binary classification and prediction approach, superior learning capabilities and high-speed response. This is an efficient alternative solution in the field of power quality. This paper introduces the linear mathematical decision-based rule to predict/ classify the sag, swell and interruption related power quality problems more precisely. Data collected from Maharashtra State Electricity Distribution Company Ltd. is used as training samples to train the classifier by means of supervisory approach. Applicability of the supervisory learning method to the classification of power quality problems is demonstrated in this paper and it can be considered as a stepping-stone in upcoming AI technologies for the power system.

This paper develops a multi-agent protection scheme for electric power distribution systems and microgrids with aggregated electronically coupled distributed energy resources (DER). The proposed protection scheme uses both voltage and current measurements to sense faults, and then trips only the faulted feeders, and broadcasts fault events to the main microgrid control system, and adjacent protective agents. The objective of this paper is to improve distribution system resilience by using a minimal communication protection scheme, and reducing power outages. Two study cases are presented. The EMTP-RV program is used to model the power system and the control systems of a PV based DER unit. The IEEE 34 bus test system is chosen for demonstration.

Distribution systems play an important role, delivering the electric power of generation system to individual consumers. Distribution system reconfiguration (DSR) is a large-scale combinatorial optimization problem. For the last 45 years, the DSR problem has been widely studied; nowadays, DSR, combined with new challenges, is being highly investigated, as researchers aim to reach a better solution. This paper presents a complete review and classification of the most significant works to date, providing a literary framework for DSR specialists. A categorization of solution methods, case studies, and novelties of the most relevant works regarding DSR are provided. In order to establish a complete background, not only traditional approaches, but also those involving uncertainty, reliability, electricity market, power quality, distributed generation, capacitor placement, and switching time in DSR are highlighted. This framework can help researches to improve previous formulations and methods and can propose more efficient models to better exploit the existing infrastructure.

This paper presents the outcomes of laboratory evaluation of the performance of a sample of LED lighting systems (lamp/driver and dimmer combinations) in presence of audio frequency injection control (AFIC) signals used by electricity distribution system network service providers (DNSPs) for control of certain loads. The testing presented in this study has been undertaken in response to a significant number of customer complaints that have been received by DNSPs related to the performance of LED lighting systems with dimmers incorporated. In a number of cases, performance issues have been verified in the field to occur during periods where AFIC signaling voltages are present in the electricity distribution network. In order to determine the contributing factors that AFIC signaling may have on the performance of the LED lighting system, a light-based flicker evaluation testing system has been developed to investigate LED lighting system performance under controlled conditions. One of the main objectives of the study was to use light-based flicker indices to identify the effect on different combinations of LED lamps/drivers and dimmers by varying the voltage magnitude and frequency of the AFIC signal as well as the position (i.e., voltage output) of the dimmer. Visual observations were also carried out to investigate the correlation between measured flicker indices and visually observed flicker. This paper presents the test results that have been analyzed in terms of types of technologies used in LED lamp/driver and the variables in the AFIC signal.

This paper presents selected security systems required for safe operation of Energy Storage System (ESS) in power distribution system especially operating with Superconducting Magnetic Energy Storage (SMES). This paper shows security issues in reference to 300 kV A power converter interface which connects electric power distribution system and SMES. Due to high dynamics, high power and large capability for instantaneous energy storage and inductive character of the storage system, there are different states of its operation which require additional security systems in order to ensure safe operation of the entire system. Selected systems are described together with simulation studies. In addition analysis of system operation are described for several blocks of ESS. An example of practical implementation is presented in a full scale prototype converter.

Smart grid is a two-way communication power grid that leads to a reliable and efficient electrical distribution grid. Smart grid technology provides a more productive usage of electricity through Artificial intelligence (AI). This paper shows the potential of implementing an optimised smart grid system with the use of Multi-Agent System (MAS) in a power grid environment. It optimises the electricity efficiency and distribution of smart grid on different level. The efficient communication of MAS and algorithm of Energy Management System (EMS) both work together to reduce electricity wastage while optimizing consumers comfort, electricity cost and reduce overloading of power supply. Thus, the optimised smart grid system was designed and developed with the use of MAS for its IEEE FIPA standards compliant communication system. Simulation studies carried out on the proposed system shows its potential to provide the optimal solutions to achieve better electricity distribution efficiency and electricity bill price. This paper demonstrates how the influences of different level of EMS with MAS decision making system will affect the smart grid.

The operation and trade of the electricity distribution market must develop based on a clear distribution pricing mechanism. Current nodal price generally does not include distribution network costs, which is not conducive to the establishment of distribution market and the efficient use of distribution network. Therefore, based on the Ramsay criterion and further considering the influence of reactive power, a method of allocating the distribution network cost to the nodal price is proposed in this paper. The main innovation in this paper is that a calculation method of price elasticity of reactive power demand is established. Consequently, the cost of the distribution network is allocated to the nodes according to not only active power distributed but also reactive power distributed. A 12-node system modified from the IEEE 33-node distribution network is used to do simulation. Results validate the feasibility and effectiveness of the method. Moreover, comparative analysis with MW-Mile method shows that the method can provide better economic information for network users.

Today's electrical energy generation and distribution systems are being faced with a number of issues, from violent weather to earthquakes and landslides, including acts of terrorism and vandalism. All these are grave concerns stemming from environmental as well as operational, and societal issues. Therefore, utilities' electric power distribution infrastructure is required to respond to such challenges very rapidly and effectively so as to preserve stability and continuity of operations. This is the true measure of what sustainable energy systems (SES) are all about and homeostaticity of energy systems seeks just that: to bring about a rapid, highly effective and optimally efficient state of equilibrium between energy supply and energy consumption in electric power systems (EPS). In this paper we present the theoretical groundwork and offer a partial example of the prescriptive homeostaticity model for controlling utility-operated microgrids. The paper explains how the engineering of homeostaticity works and how reactive and predictive homeostasis, acting concomitantly, play a key role in these systems dynamics, namely the grid-tied microgrid, the grid and the energy consumers. Reactive homeostasis (RH) is an immediate response of the energy system to a homeostatic stress or perturbation, such as energy deprivation or shortage or an energy imbalance. RH entails feedback mechanisms which enable a reactive compensation when the need arises, reestablishing homeostaticity in the system. Predictive homeostasis (PH), on the other hand, anticipates the contingencies that are likely to occur, and then acts upon them enabling the energy system to respond in a proactive manner to environmental challenges and/or other concerns. Major aspects of the model are briefly explained along with the mechanics of homeostasis applied to SES and expected results.

This paper explains about the performance and application of Energy Management System (EMS) in Higher Educational Institutions (HEI). Using this proposed system we can promote Smart institutions with rich sustainability and better supervision over the grid. The costs on electricity consumption of educational Institutions have been rising enormously since the last decade. There have been no measures taken to monitor the individual energy demand throughout the day which plays a major role in the calculation of electricity bill. The HEI spend more on heating, air conditioning and lighting load than on any other expense. This paper proposes a simple solution that shall keep the rising electricity bills in limits. The energy costs can be reduced by proper management of electricity distribution among various sections in the campus. This paper briefly confers the different methods that have to be put into practice in order to control the Energy demand. Also, this paper discusses about an innovative building automation and energy management system that is core to the institution's comfort and Sustainability requirements.

With accelerated adoption of long range electric vehicles (EVs) lightweight and highly efficient on-board chargers (OBCs) are desirable. At the same time, development of OBCs capable of operation with single and three phase (truly universal) input offers the most versatile charging solution to EV owners regardless of their access to the electricity distribution network. In this work, use of two bridgeless current-fed push pull converters with active clamp is proposed as a truly universal bridgeless single-stage AC/DC converter for on-board charging application. The building blocks of the proposed topology achieve soft-switching and operate in continuous conduction mode with constant switching frequency. The diode bridge is eliminated at the AC input, which results in a simpler thermal management and significant savings in conduction losses. Principle of operation for the proposed converter and details of the proposed control scheme are illustrated in this paper. Proper operation of the converter and effectiveness of the control are verified through PSIM simulation for a truly universal 360V 5.4 kW single stage OBC.

This paper discusses the aspects of the development of the pricing of electricity distribution. The operational environment of the Distribution System Operators (DSO) is changing due to various factors. The DSOs have to take actions in order to ensure that the qualifications for a stable and sustainable business are still present in the future. One way to ensure this is that the DSOs start developing their pricing practices. Especially tariffs, which include a capacity related component, are seen as a potential development direction. The paper includes a case study of power-based pricing, where data from two Finnish DSOs are applied. The results show that the customer impacts in both cases would not be massive for the majority of the small customers, which is central from the successful tariff reform viewpoint. Additionally, two Finnish DSOs have gradually started to apply a power-based distribution tariff (PBDT) to their small customers. acceptedVersion

Smart Grids and innovation in electricity distribution utilities can provide a variety of benefits: they can deliver cost savings and thereby reduce the cost to rate-payers; they can raise standards of service, such as reducing interruptions experienced by consumers; or they can allow the utility to deliver a wider scope and provide new services within its existing cost base. Smart Grid techniques are increasingly a topic within rate reviews and regulatory settlements. This paper illustrates the experience within Great Britain of the electricity distribution network price control settlement known as RIIO-ED1. The paper illustrates the importance for utilities, government agencies and regulators to clarify which of the objectives, or whether all the objectives, are being pursued with Smart Grids. Without a common language, a technique may be offered to improve customer service, and yet be allocated a cost reduction target — or vice versa.

This paper presents a bibliographical survey of different methods used for state estimation in electric power distribution network. Since several decades state estimation techniques have been applied for real-time monitoring, control and protection for transmission network. However, the recent distribution networks are operated actively, so state estimation plays a crucial role in energy management system (EMS) for online monitoring and control of distribution network. Because of the special characteristics of distribution systems, some of the well established state estimation techniques applied in transmission system cannot be migrated directly to distribution level for state estimation. The distribution state estimation is the integral part of the Smart-grid. A survey on all those techniques used in distribution network is presented in this paper. The future direction of the DSSE is also presented.

Global Energy Internet has complex dynamic characteristics which are influenced by the international politics, economy and energy patterns and other factors. Political emergencies affect the trend of global oil price, which furthermore, influences global energy consumption and electric power distribution. This paper adopts econometric method to study the impact of political emergencies on global oil price. It describes the political emergencies with dummy variables and establishes the total intervention model with time series analysis method and intervention analysis method. Based on the proposed method, impact of political emergencies on global oil price is studied with typical cases such as Gulf War and 911 Event. This paper is aimed to guide the analysis of macroscopic characteristics of Global Energy Internet.

The increased penetration of renewable energy resources poses challenges for grid stability. The stochastic generation of solar and wind power cannot be controlled to follow load. And, the transition away from synchronous generators is reducing the capacity to arrest and recover from frequency disturbances. Smart electric water heaters provide utilities with an appliance that can be remotely controlled and serve as a form of energy storage. They have very fast response times and make up a large amount of residential energy consumption, making them useful for load peak shifting as well as other ancillary grid services. As smart appliances become increasingly widespread, more and more devices can be brought into the utility control network and aggregated into a flexible resource on a multi-megawatt scale. This paper demonstrates the usefulness of aggregated electric water heaters for providing two ancillary services: peak shifting and frequency response. Because a large number of assets are required, emulators are developed based on observations of real devices. Emulated water heaters are then connected to an energy resource aggregator using an internet-of-things network. The aggregator uses these assets to shift consumption away from peak hours and for detecting upward frequency disturbances.

The pressure of climate change and the need for the adoption of renewable sources have led to a strong development of technology within microgrids (μG). The modular and scalable nature presents opportunities for the development of a new class of users in μG (i.e. the prosumers). The large-scale integration of small-scale renewable energy sources (SSRES) creates challenges for today's classic electricity distribution networks. The paper proposes a simulation method for optimal integration of prosumers to minimize active power losses in μG. For a deeper analysis regarding the influence of the prosumers on the μG power losses, 24 hour real load consumption and generation profiles are used. The study's findings show that a more effective μG operation by the optimal allocation of the PV panels on the μG can decrease the active power losses up to 35% in a day.

© 2017 IEEE. Distributed solar photovoltaic (PV) generation market continues to grow with increasing operational challenges for distribution network operators. In South Africa, residential solar PV system projects have also been implemented in low voltage distribution networks, and there are plans for future projects at municipal level. Residential solar PV growth introduces more technical and economic concerns in municipalities and electricity utility network operators. This paper focusses on a technical investigation of a more practical low voltage (LV) distribution transformer performance under high distributed solar PV connections on eThekwini Electricity distribution network. The main network parameters of interest investigated in this paper include LV network power flow, line voltage dynamics and distribution feeder power losses in steady state. Customer day load demand effects on network parameters are also analyzed, at discrete levels, with discrete off-load tap-changer positions and different solar PV penetration levels. A case study residential LV distribution network of eThekwini Electricity is used in this paper to assess central transformer performance.

This paper describes selected issues concerning realization of energy storage system (ESS) designed to operate in power distribution system. This paper presents a modular approach of 300 kVA power converter operating with superconducting magnetic energy storage (SMES), which gives high dynamics together with high power and suitable capability for instantaneous energy storage. Analysis and simulation studies of selected power converter topologies are conducted, which are also commonly used to connect electric power distribution system and energy storage system. In order to verify assumed technical parameters, a single prototype of ESS is presented together with experimental results. Proposed solution supports scalability of the system in power as well as in energy storage capacity of ESS. Presented full scale prototype module is a result of conducted analysis and proposition for future renewable energy storage installations.

Power electronic devices are finding increasing applications in the control, instrumentation, and switching in electric power distribution systems. Applications include solid state transformers and solid state fault interruption devices. Some of these devices may be connected directly to the distribution primaries (typically in the 15 kV class). This paper addresses the concerns related to the direct galvanic (ohmic) connection of solid state components directly to the distribution primaries. The focus of the paper is on the basic impulse insulation level (also known as the lightning impulse withstand level). The application of the International Electrotechnical Commission standard 60071 is discussed. Some results of impulse testing of distribution system components, based on applications in the Future Renewable Electric Energy Delivery and Management Engineering Research Center (FREEDM), are reported.

In this paper, we study the development options of tariff structures in electricity distribution in Finland. We compare the impacts of three different tariffs from the viewpoints of customers, distribution system operator (DSO), electricity supplier, and society. Analyzed tariffs are (1) energy oriented tariff, which is currently in use, (2) power limit tariff, and (3) power tariff. Based on the analyses, it seems that it is justified to include power based price component in distribution tariff. Generally, the impacts of both analyzed power based tariffs are quite similar. However, it seems that power tariff is a bit stronger candidate. Nevertheless, it should be noted that the benefits of the power-oriented pricing, illustrated in the paper, could be achieved only by well-designed tariff system. Although analyses are based on Finnish case, most of the results are generalizable to other countries also. acceptedVersion

In this paper, an innovative transformer load monitoring system by utilizing smart meter data has been designed to determine the daily power profile of distribution transformers. A two-stage load estimator algorithm that combines customer load pattern from smart meters and state estimation (SE) theory is developed to provide the secondary output power of distribution transformers in the low voltage network at a sound accuracy with customer smart meter measurements. The estimated results that could reflect true transformer loading within 15 min intervals then are used for transformer load management. A data visualization based hanuman machine interface is also designed to allow operators to intuitively monitor the loading levels of distribution transformers. Test results of a practical distribution feeder with 12 transformers in Taipower are presented. The methodology proposed in this paper can effectively assist electric utilities for the evaluation of loading factors of distribution transformers to prevent the burn out of transformers caused by overloading problem. The operation efficiency of distribution systems can also be enhanced by loading balance of distribution transformers.

This paper describes selected issues concerning realization of energy storage system (ESS) designed to operate in power distribution system. In order to achieve scalability of the system a modular approach is proposed. In addition to this different configuration of the system are analyzed, where depending on requirements and application a scalability in power, in energy capacity of energy storage resource and both in power and capacity are analyzed. This paper presents results of operation of the simulation model for 250kW of rated power for classical two level converter and neutral point clamped (NPC) three level converter. According to the simulation results a new, full scale and modular, 250 kW prototype of ESS is presented, which enables to operate with various energy storage resources such as superconducting magnetic energy storage (SMES) and supercapacitor energy storage (SES), which is a product of presented analysis.

International audience; This paper presents a case study on emerging challenges within collaborative innovation projects engaging open communities. Innovation driven by open communities has proven to have a significant potential, in particular for open source software. However, tools and methodologies enabling the supervision of collaborative innovation involving open communities, in the perspective of creating open hardware to solve societal issues, remains at the early stages. This paper seeks to pinpoint the potentialities and challenges of such projects toward defining methods to better support a multi-stakeholders open source collaboration context. The experimental field of this research concerns the smart electricity distribution, and more precisely a public driven project of the diffusion of smart-meters in France and their appropriation by open source communities, with the involvement of the university and a public industrial company. The project seeks to study how these communities of users develop in a collaborative manner, new products and services using the smart-meter as a support technology. The first results show that the open community makes natural connection on specific environments such as Smart buildings to materialize usages of smart meters.

Electric energy is the cleanest and more efficient energy type that is being transmitting and distributing among end users. From early evolution, ac distribution was selected as better, from economic point of view, solution for transmission and distribution purpose. However last technological development in electronic device is changing many things. This paper reconsiders DC and ac distribution systems. In particular the paper describes the fundamental aspects in order to compare these solutions from economic point of view and to find better proposal in order to realize new grid or add new loads to an existing grid or even change current ac infrastructure to the DC one. To reach this goal, the paper introduces a cost analysis about the electronic device installed in a LV network. Theoretical evaluation has been conducted and a three line DC distribution is selected as possible economic solution for DC LV grid. A case study is performed to evaluate if it is beneficial to change/build a DC distribution system instead of an ac one.

This paper is focused on challenges related to an increased quantity of distribution energy resources connected to the distribution network within the context of newly defined requirements ENTSO-E, follow-up European standards TS 50549 and codes of distribution system operators on regulation of voltage through control of the reactive power in terms of P-Q diagram. A high number of connected and operated distribution energy resources results in changes in quality parameters of voltage in a distribution grid. The evaluation of the measured parameters enables to detect overvoltage or voltage fluctuations that are not in accordance with requirements of EN 50160 standard. This paper describes courses of voltage during operation of a wind energy converter (WEC) operated in parallel with the CEZ Distribuce distribution network (DN) on medium voltage (MV) level with the prescribed control of the reactive power to a fixed value of a power factor and the control of the reactive power depending on voltage. The measurement results of U, P, Q values evaluate an influence of the voltage reactive power in a point of connection of a power generating plant to the grid with regard to keeping the voltage within a range of operating limits.