Comparative Synthetic Inertia Assessment Between Droop And Virtual Synchronous Generator Control For Weak Grids Integration

With the continuous increase of the penetration of renewable power generation (RPG), the rotating reserve capacity and moment of inertia in the power system are relatively reduced, which brings serious challenges to the safe and stable operation of power systems. To address this issue, the droop control and virtual synchronous generator (VSG) control strategies have been proposed, their configuration and dynamic characteristics have been fully investigated. To further investigate the synthetic inertia and dynamic response of these two methods, theoretical analysis of the inverter implanting these two control strategies is performed. The results indicate that both control strategy has inertia, the inertia of droop-controlled inverter is only determined by damping factor, while the virtual inertia of virtual synchronous generator-controlled inverter is simultaneously affected by the virtual inertia coefficient and damping coefficient, it is much similar with an actual synchronous generator (SG). Finally, electromagnetic transient simulations are conducted to validate the inertia analyze and the dynamic characteristics.