Accurate Reactive Power Sharing Strategy Based on PSO for Improved Virtual Capacitor Algorithm in Multi-Paralleled Distributed VSGs

In multi-paralleled distributed virtual synchronous generators system, due to the randomness of the geographical location of the virtual synchronous generators, there are differences in the line impedance of each virtual synchronous generator in the system, and the system reactive power cannot be reasonably shared according to the capacity. To address this issue, an improved reactive power sharing strategy based on particle swarm optimization for virtual capacitor algorithm is proposed. The proposed strategy adopts an algorithm to mimic the characteristics of the parallel capacitor at the output of the virtual synchronous generator to compensate for the voltage, eliminating the impact of the difference in line impedance. At the same time, the particle swarm optimization is used to optimize the virtual capacitor control strategy for the difficulty of parameter adjustment. The control strategy proposed in this paper can improve reactive sharing precision, and at the same time improve the voltage control precision and system stability. Finally, simulation is carried out by Matlab/simulink to verify the feasibility and effectiveness of the method.