A Bandwidth-orienting Simplified and Design Method for Multiple VSG Parallel System

The multiple virtual synchronous generators (VSG) parallel systems have more complex interactions between VSGs. However, the dynamic performance and stability of the system are hard to analyze accurately and quickly in traditional methods, such as state space method and small signal method. Thus, a bandwidth-oriented simplified and design method is proposed for multiple VSG parallel systems. Firstly, models of voltage loop and power loop are established to present the interaction in frequency bandwidth. Then, a design method of voltage controller and power controller is proposed, and a simplified model of multiple VSG parallel systems is established for fast and accurate analysis and simulation of dynamic performance. Moreover, the system operation of the simplified model and exact circuit model under different bandwidths of voltage loop is compared. Finally, the accuracy of the simplified model and its applicability in complex systems are verified in MATLAB/Simulink simulation platform.