http://hdl.handle.net/20.500.14044/34886 2026-07-26T00:41:10Z http://hdl.handle.net/20.500.14044/34895 Electrical Protection Systems for the Evolving Microgrid Environment Bobček, Marek; Štefko, Róbert; Čonka, Zsolt This article explores the vital aspects of grid protection within the context of microgrids, focusing on current grid protection techniques. As microgrids gain prominence in the modern energy landscape, the need for effective protection measures becomes increasingly critical. The article delves into the fundamentals of relay protection and its role in safeguarding microgrid assets. To provide a comprehensive understanding of these protection methods, the article uses simulation models in Simulink, offering insights into the impact of various sources of electrical energy on the grid, as well as providing simulated protection models within microgrid systems. Through highlighting the unique challenges and considerations associated with grid protection in microgrids, this article serves as a valuable resource for researchers, engineers, and practitioners striving to enhance the reliability and security of microgrid operations 2023-01-01T00:00:00Z http://hdl.handle.net/20.500.14044/34894 The Role of Flexibility Resources in the Energy Transition Koltsaklis, Nikolaos; Knápek, Jaroslav Extremely adaptable power systems are required, as the share of variable renewable energy sources increases. The variable renewable energy sources' ability to be installed on the grid, is frequently thought to be constrained by a limited flexible capacity. A general, methodological framework, for the optimal scheduling of an islanded power system, with a variety of flexibility resources, is presented in this work. In particular, it takes into account a significant amount of intermittent RES and the widespread use of electric vehicles that offer charging and discharging options. The modeling in this work also considers demand response programs' active market participation and the installation of energy storage capacities. Additionally, it covers the involvement of electricity interconnections, as a source of flexibility. Two illustrative case studies of an island power system connected to a mainland power system, have been used, to evaluate the applicability of the proposed strategy. The scheduling framework is daily, with an hourly interval. The results of the modeling show how important all of the flexibility resources are, for effective energy management and the supply of ancillary services, especially in cases for high-RES penetration. The proposed method can be used by market operators, policymakers and regulatory authorities, to choose the best system development, market design and portfolio synthesis.; Extremely adaptable power systems are required, as the share of variable renewable energy sources increases. The variable renewable energy sources' ability to be installed on the grid, is frequently thought to be constrained by a limited flexible capacity. A general, methodological framework, for the optimal scheduling of an islanded power system, with a variety of flexibility resources, is presented in this work. In particular, it takes into account a significant amount of intermittent RES and the widespread use of electric vehicles that offer charging and discharging options. The modeling in this work also considers demand response programs' active market participation and the installation of energy storage capacities. Additionally, it covers the involvement of electricity interconnections, as a source of flexibility. Two illustrative case studies of an island power system connected to a mainland power system, have been used, to evaluate the applicability of the proposed strategy. The scheduling framework is daily, with an hourly interval. The results of the modeling show how important all of the flexibility resources are, for effective energy management and the supply of ancillary services, especially in cases for high-RES penetration. The proposed method can be used by market operators, policymakers and regulatory authorities, to choose the best system development, market design and portfolio synthesis. 2023-01-01T00:00:00Z http://hdl.handle.net/20.500.14044/34893 Demand-Supply Balancing in Energy Systems with High Photovoltaic Penetration, using Flexibility of Nuclear Power Plants Diahovchenko, Illia; Yevtushenko, Ihor; Kolcun, Michal; Čonka, Zsolt; Zahorodnia, Tetiana Energy transition requires scaling up the supply of low emissions electricity from renewable energy sources (RESs) and acceleration of deployment of dispatchable sources of low emissions electricity such as hydro and nuclear. Power output from RESs, particularly photovoltaic (PV) generation, can vary periodically and irregularly, depending on weather conditions. At high PV penetration levels, this peculiarity of the technology can not only cause voltage and power flow fluctuations in the local distribution grids, but also violate the demand-supply balance of a whole energy system, resulting in issues with frequency control and difficulty of demand supply management. This study is primarily focused on demand and supply balancing of an energy system with high PV penetration levels, assuming a significant share of nuclear power plants (NPPs), as well as thermal power plants (TPPs) and a strong transmission system. The potential benefits of flexible nuclear operations in an energy system are analyzed. It is demonstrated that nuclear power plants’ flexibility can reduce the share of environmentally unfriendly thermal power units and substantially reduce the restrictions for renewable energy. The IEEE 9-bus test system is used for the case study. 2023-01-01T00:00:00Z http://hdl.handle.net/20.500.14044/34892 Energy Storage System Utilization, in a Distribution Power System Medved, Dušan; Beňa, Ľubomír; Jitendrakumar Tailor, Rikin The contribution of energy storage systems (ESS) to the electricity system is the subject of this paper. There were implemented aspects that are extremely popular and typical in power system setup according to distribution network characteristics. For this reason, a power network included sources like wind farms and solar farms, and in some unfavorable situations, the distribution network link was used as a backup source of electricity. In this power system, load was seen as having constant power. Energy storage systems were put into place throughout the simulation to make up for lost power until a particular stage of discharge, at which point connections to the distribution system (DS) were made. Simulations were carried out in the Matlab/Simulink environment, to examine the collaboration of the aforementioned elements, over a 48-hour period, under various conditions. 2023-01-01T00:00:00Z