Virtual Synchronous Generator Controller for Power Quality Enhancement in Microgrids

Today, the overuse of nonlinear loads in island microgrids (MGs) are created problems such as poor harmonic load distribution and voltage distortion. To solve these problems, this paper proposes a control method to reduce main voltage harmonics selectively. This method uses a virtual synchronous generator (VSG) based control to compensate the harmonic voltage created by the passing harmonic current in output impedance, via adding the appropriate amount of harmonic voltage to the inverter voltage reference. After examining the primary principles of power transmission to a constant current source, harmonic VSG controller is created, which significantly reduces total harmonic distortion (THD). To evaluate the performance of the harmonic VSG controller, this controller is compared with the droop controller. Simulation results show the improvement of power quality in terms of voltage THD using VSG-based harmonic mitigation strategy.