Virtual Synchronizing Torque and Voltage Controller Based Grid Synchronization of Virtual Synchronous Generator

Abstract

Ever increasing penetration of voltage source converter (VSC) based renewable energy sources causes various concerns on stability issues for power system. This is due to less inertia of these renewable sources unlike the synchronous generators. Therefore, the grid integration of voltage source converter (VSC) based distributed energy sources (DES) becomes very challenging. The emergence of virtual synchronous generator (VSG) have become quite popular in recent times because of overall inertia improvement in power grid. For the reliable operation of VSG, smooth switching of VSCs between islanded and grid connected mode is required to avoid large inrush current at the time of mode switching. Previously, phase locked loops (PLLs) have been used to get phase, frequency and magnitude of grid voltage for synchronization purpose. This paper presents the virtual synchronizing torque and virtual voltage based synchronization controller for effortless switching between islanding and grid tied modes. Effectiveness of the proposed controller has been verified in MATLAB/Simulink platform. Proposed control method is also compared with synchronization methods present in literatures. © 2022 IEEE.