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Power generation, distribution, transmission, and consumption face ongoing challenges such as smart grid management, control, and operation, resulting from high energy demand, the diversity of energy sources, and environmental or regulatory issues. This paper provides a comprehensive overview of blockchain-based solutions for smart grid management, control, and operations. We systematically summarize existing work on the use and implementation of blockchain technology in various smart grid domains. The paper compares related reviews and highlights the challenges in the management, control, and operation for a blockchain-based smart grid as well as future research directions in the five categories: collaboration among stakeholders; data analysis and data manage-ment; control of grid imbalances; decentralization of grid management and operations; and security and privacy. All these aspects have not been covered in previous reviews. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. open access

Power generation, distribution, transmission, and consumption face ongoing challenges such as smart grid management, control, and operation, resulting from high energy demand, the diversity of energy sources, and environmental or regulatory issues. This paper provides a comprehensive overview of blockchain-based solutions for smart grid management, control, and operations. We systematically summarize existing work on the use and implementation of blockchain technology in various smart grid domains. The paper compares related reviews and highlights the challenges in the management, control, and operation for a blockchain-based smart grid as well as future research directions in the five categories: collaboration among stakeholders; data analysis and data manage-ment; control of grid imbalances; decentralization of grid management and operations; and security and privacy. All these aspects have not been covered in previous reviews. CC BY 4.0© 2021 by the authors. Licensee MDPI, Basel, Switzerland.

The paper focus on the benefits of close integration of battery based energy storage directly into thermal plants. The attention is paid to use of the energy storage for primary frequency control in cooperation with classical steam turbine control. The model topology of the turbomachinery with all modifications is described and discussed. Three case studies are investigated – the primary frequency control managed by either only turbine, only energy storage and by cooperation of both turbine and energy storage. The other benefits of integration energy storage into power plant systems are discussed in the conclusion.

Industrial Internet of Things is one of the opportunities for online state monitoring, effective control and economical profitability of selected systems. The majority of electricity generated in the Czech Republic comes from conventional fossil power plants - 54% in 2018. Same fact applies to heating where approximately 82% of heat in 2018 was generated from fossil fuels. Despite the fact that energy is being saved and the efficiency on the final customer side is improving, our demand of energy is rising. Over the last few years the online measurement of operation parameters plays a big role in performance optimization and energy management. Following article describes an Open source / Matlab IIoT platform used for monitoring and possible optimization of a district heating network in a typical Czech residential district and electrical island operation of a electrical power system.

36th European Photovoltaic Solar Energy Conference and Exhibition; 1403-1409, Electric power grids are increasingly penetrated by generation from photovoltaic (PV) systems. The volatility of solar irradiance can therefore cause problematic fluctuations of grid voltage and frequency. For local low voltage power grid sections highly accurate nowcasts of the short-term local PV-power generation may enable higher PV penetration by employing short-term flexibility options while saving investments in grid-infrastructure. Systems of up to four All-Sky-Imagers (ASI) have been used successfully to nowcast direct and global irradiance as well as the production of solar power plants. In Oldenburg and the surrounding area these systems are enhanced by interconnecting 34 All-Sky-Imagers in a measurement network called Eye2Sky. Intermediate results can be combined and exchanged between systems with overlapping observation areas but also between systems up to 100 km apart. To demonstrate the potential of the approach three state-of-the-art 2-ASI-systems from the network are selected. Nowcasts of the individual systems are averaged weighting each prediction by its expected accuracy in the single points of the forecast domain. In a validation period of 86 days the network outperforms a single 2-ASI-system. For all lead times greater than zero, significantly lower root mean square errors are found compared to the 2-ASI system. For highly variable time intervals the root mean square error is reduced by up to 50 %. The network´s combined nowcast is found to reduce forecast errors related to the often uncertain cloud edge positions and further systematic errors found in single 2-ASI-systems.

This paper presents the performance evaluation under grid voltage sags of a two parallel-interleaved grid-connected converters employing low switching frequency. A current controller based on the synchronous reference frame including voltage feed-forward is used. The dominant frequency components from the direct- and quadrature-axis voltage Vd and Vq are eliminated by using an adaptive moving average filter. The dynamic performance of the converter during voltage sags is improved using an adaptive approach which minimizes the filter delay during the faults. The presented results conclude the performance of the converter system.

In recent years, low voltage electrical grids are experiencing the growing implementation of distributed generation systems such as solar and wind generators, EV charging systems and storage devices. For this reason the use of a smart management system for every active component becomes necessary to acquire and provide real time measurements of main parameters of power grids and execute automatic actions. In this work, the design and implementation of a cheap, flexible and reliable smart monitoring system is proposed.

29th European Photovoltaic Solar Energy Conference and Exhibition; 3587-3591, The OrPHEuS project elaborates hybrid energy network control strategies for smart cities implementing novel cooperative approach for the optimal interactions between multiple energy grids. The OrPHEuS project aims at optimising the synergies between multiple energy grids by enabling simultaneous optimization for individual response requirements, energy efficiencies and energy savings as well as coupled operational, economic and social impacts. The project will investigate the implementation of the control strategies on specific use cases scenario in two demonstration sites located in the City of Skellefteå in Sweden and in the City of Ulm in Germany. The operational focus of the project is the cross-domain coupling of energy infrastructures in order to increase energy efficiency through energy transformation and grid coupling. In particular, the project researches scenarios for transition between energy resources and flexible infrastructures e.g. along Power-to-Heat processes. It investigates the balancing of fluctuating renewable energy generation against the flexibility in supply, demand and storage capacities within the power grid and via process coupling across energy networks. The project will look on technical as well as socio-economical aspects considered as multi-dimensional strategy framework. With respect to the hybrid energy characteristics, both demonstration sites are quite distinct. At the demonstration site in Sweden, the reduction of vertical production (driven unsustainable with fossil fuel) is in the centre of the targeted control strategies. Looking on the specifics of the Ulm testing site, the major issue is the balancing of the high penetration of solar generation under today’s operation with a pre-dominant operational challenge for PV control. The key focus is to define control strategies to increase the intake of the energy supply from PV on the roof generation into the grid while maximizing the benefits for the low voltage power grid. The 29th European Photovoltaic Solar Energy Conference and Exhibition (EU PVSEC) in Amsterdam represented a unique opportunity to present information on the methodology adopted by the OrPHEuS Consortium to optimise the synergies between multiple energy grids. On the occasion of the EU PVSEC the OrPHEuS Consortium focused the project presentation on how to optimise the PV electricity production with the implementation of Information and Communication (ICT) devices at the Ulm demonstration site, the Test area in Einsingen, which presents an over production of the PV electricity of 230 MWh annually. The average annual electrical consumption is around 1000 MWh.

International audience; This paper investigates the dynamic behavior of a high-power wind energy conversion system (WECS) connected to the grid. The system includes a three-bladed horizontal wind turbine, a permanent magnet synchronous generator (PMSG) with a high number of poles which eliminate the gearbox. A back to back converter is used between the generator and the grid. A random profile of the wind speed has been used, in order to illustrate the various controls performed. The results of the simulation in Matlab\Simulink have been obtained and discussed to validate the control strategy.

The paper investigates the potential of using lumped stationary battery energy storage systems (BESS) in the public low-voltage distribution grid in order to defer upgrades needed in case of large penetration of electric vehicle (EV), electrified heat pump (HP) in presence of photovoltaic (PV) panel on the view of techno economic optimal sizing taking the consideration of season-based diurnal dynamics. The BESS is primarily dimensioned for the peak shaving operation targeted for the counterbalance of overloading of transformer; BESS also participates in arbitrage (buy low, sell high) application. The paper assesses the effects of a PV-BESS combination and the control of such a system with the help of a newly devised season specific BESS control protocol that ensures the availability of energy for peak-shaving purpose (namely peak period in winter) and it participates in arbitrage. The objective of this paper is to develop and detail the method of optimum sizing energy storage for grid connected distribution systems using newly devised BESS control protocol and investigate its sensitivity to factors which are known to influence energy system performance and hence storage requirements. The results provide insight into the dimensioning and the required specification and configuration of BESS.

Sinds de laatste jaren is er in het elektrisch energienet een enorme toevloed aan kleine decentrale generatoren, vaak op basis van hernieuwbare energiebronnen. De distributienetten werden echter niet gebouwd om injectie van energie toe te laten. Hierdoor komen steeds meer problemen in de distributienetten voor, zoals bijvoorbeeld overspanningen tijdens zonnige periodes. Dit bemoeilijkt de verdere integratie van hernieuwbare energiebronnen. In deze context werd het microgrid concept voorgesteld om een gecoordineerde koppeling van decentrale generatoren in het net mogelijk te maken. Microgrids zijn kleine subnetten die lokaal hun elementen, zoals de generatoren en de lasten regelen om bepaalde doeleinden te bereiken. Ze kunnen bijvoorbeeld de spanningsregeling in hun net verzorgen of als een geheel meespelen in de energiemarkten. Een karakteristiek van microgrids is dat ze onafhankelijk van het net kunnen werken, in het zogenaamde eilandbedrijf. In eilandbedrijf moeten het verbruik en de opwekking op ieder tijdstip op elkaar afgesteld zijn. Aangezien microgrids erg verschillende eigenschappen hebben van het gewone elektrisch net, zijn hier specifieke regelstrategieen voor vereist. In deze doctoraatsverhandeling wordt een dergelijke regelstrategie uitgewerkt, de zogenaamde spanningsgebaseerde droop (proportionele) regeling. Het spanningsniveau wordt als de niet-conventionele parameter gebruikt om het microgrid te regelen.

For planning issues, it is useful to know the upper limit for photovoltaics (PV) in the electrical grid with current design and operation (defined as hosting capacity) and how this limit can be increased. Future costs for grid reinforcement can be avoided if measures are taken to implement smart grid technology in the distribution grid. The aim of this project is to identify challenges in Swedish electricity distribution grids with a high penetration of local generation of electricity from PV. The aim is also to help Swedish Distribution System Operators (DSOs) to better understand hosting capacity issues, and to see which room for PV integration there is before there is need for actions to maintain power quality. Three distribution grids are modelled and simulated in Matlab: Rural area, Residential area and City (Stockholm Royal Seaport). Since the project is a cooperation between Uppsala University and Fortum, three different representative grids from Fortum’s grid software ”Power Grid” have been used as input to a flexible simulation program developed at Uppsala University. The simulation includes Newton-Raphson power-flow computing but has also been improved with a model of the temperature dependency of the resistance. The results show that there is room for a lot of PV systems in the Swedish grids. When using voltage rise above 1.1 p.u. voltage as limitation, the hosting capacity 60% PV electricity generation as a fraction of the yearly load were determined for the rural grid and the suburban grid. For the city grid, which is very robust, the hosting capacity 325% was determined. When using overload as limitation, the hosting capacities 70%, 20% and 25%, were determined for the same grids.

Artykuł przedstawia możliwości rozwiązania Oracle Grid Control oraz jego zastosowania w obszarze zarządzania i administrowania podsystemami składowymi w złożonych, korporacyjnych systemach informatycznych. Tytułem wstępu autorzy kreślą krótki rys historyczny przedstawiający ewolucyjną drogę rozwoju systemów firmy Oracle do zarządzania infrastrukturą informatyczną. W kolej¬nym rozdziale przedstawiona zostaje obecna koncepcja firmy Oracle, w oparciu o którą zbudowane są wspomniane systemy oraz możliwości aplikacyjne rozwiązania Grid Control. W dalszej części artykułu autorzy przedstawiają możliwości rozszerzenia funkcjonalności rozwiązania Grid Control na przykładzie stworzonego modułu do monitorowania wyników audytu bezpieczeństwa. Artykuł kończą rozważania co do dalszych możliwych zastosowań rozszerzania funkcjonalności rozwiązania Grid Control., Studia Informatica, Vol 31, No 2B (2010)