Optimal Management of Energy Consumption in an Autonomous Power System Considering Alternative Energy Sources

This work aims to analyze and manage the optimal power consumption of the autonomous power system within the Pamir region of Republic of Tajikistan, based on renewable energy sources. The task is solved through linear programming methods, production rules and mathematical modeling of power consumption modes by generating consumers. It is assumed that power consumers in the considered region have an opportunity to independently cover energy shortage by installing additional generating energy sources. The objective function is to minimize the financial expenses for own power consumption, and to maximize them from both the export and redistribution of power flows. In this study, the optimal ratio of power generation by alternative sources from daily power consumption for winter was established to be hydroelectric power plants (94.8%), wind power plant (3.8%), solar photovoltaic power plant (0.5%) and energy storage (0.8%); while it is not required in summer due to the ability to ensure the balance of energy by hydroelectric power plants. As a result, each generating consumer can independently minimize their power consumption and maximize profit from the energy exchange with other consumers, depending on the selected energy sources, thus becoming a good example of carbon-free energy usage at the micro-and mini-grid level. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

A Novel Approach of Synchronization of Microgrid with a Power System of Limited Capacity

Currently, active networks called microgrids are formed on the basis of local power supply systems with a small share of distributed generation. Microgrids operating in an island mode, in some cases, have the ability to transfer electricity excess to an external network leading to a synchronization requirement; thus, the optimization task in terms of the system’s synchronization must be considered. This paper proposes a method for obtaining synchronization between microgrids and power systems of limited capacity based on a passive synchronization algorithm, allowing us to connect a microgrid to an external power system with a minimum impact moment on the shaft of the generating equipment. The algorithm application was demonstrated by considering a real-life object in Tajikistan. The simulation was carried out on RastrWin3. The obtained results show that the microgrid generator is connected to an external power system at an angle of 0.3◦ and a power surge of 29 kW, unlike the classical synchronization algorithm with an angle of 6.8◦ and a power surge of 154 kW (a reduction of the shock moment by more than five times). The proposed synchronization method allows us to reduce the resource consumption of the generating equipment and increase the reliability and efficiency of the functioning units of the examined power system. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

Features of Electricity Distribution Using Energy Storage in Solar Photovoltaic Structure

The intensive development of renewable energy, especially solar power and wind power plants, poses risks of disrupting the balance reliability of the grid. There is the need to develop electricity storage system area, first of all, due to the global tendency to increase the demand for electricity and the number of electricity generation from renewable sources. The issue of guaranteeing electricity supply to the consumer operating in the autonomous renewable source – energy storage device – consumer system is the main criterion when selecting the installed capacity of the generator on the basis of renewable sources and energy storage device capacity. Also, the application does not allow reducing voltage fluctuations in the renewable sources – the consumer system