Single-stage Grid-connected Photovoltaic Generation Takes Part in Grid Frequency Regulation for Electromechanical Transient Analysis

In order to solve the problem of insufficient frequency regulation capacity caused by the large-scale grid-connected photovoltaic (PV) generation, the active power-frequency droop control strategy and virtual inertia control strategy are proposed for single-stage grid-connected PV generation for electromechanical transient analysis. By modifying the control structure of the inverter, PV generation actively got involved in frequency regulation. The simulation results indicate that: the inverter can control the PV array to increase or decrease the active power generated according to the set droop control and virtual inertia control, so as to suppress the drop or rise of the grid frequency; in the dynamic process of frequency, the incremental power of PV generation induced by the dynamic action of the voltage vector of grid connection point is dependent on its virtual inertia control.