Voltage Control in Electrical Grids with Virtual Power Plants with Variable Load on PV Generation

The problems of distributed voltage control in electrical grids (EGs) with virtual power plants as part of the converter-interfaced generation group are studied. It is proposed to control the VPP modes by controlling the reactive power of converter-interfaced generation, primarily of solar power plants. It is proposed to use the mean square deviation of the voltage in the converter interfaced generation (CIG) installation nodes as the main criterion of the target function. Active losses in the electrical grid are used as an additional criterion. To solve the extremum problem, it is proposed to use the extremum seeking control (ESC) method, in which the disturbances are distributed in time for each variable, wherein the disturbances occur at the same frequency. The examples provided have shown the improvement of the voltage in the EG with the virtual plant at different levels of reactive power generation limitation. The influence of the limitation value increase on the reactive power of CIG on the mean square deviation of the voltage of the virtual plant is analyzed. The operation of the test ieee33 EG at a significant CIG power of 46% of the total power of the EG loads is considered according to the norms of the standard EN50549-1:2019 to obtain the optimal value of the average daily value of the mean square deviation of the voltage, and conclusions regarding the law of controlling the reactive power of the SCG are drawn.