On Design of DC-Link Voltage Controller and PQ Controller for Grid Connected VSC for Microgrid Application

The paper presents design of two controllers for grid-connected Voltage Source Converter (VSC) of Microgrid. The control objective is to provide power sharing from renewable sources of Microgrid to main grid. The PV, BESS and wind system need VSC for grid connection. Both DC-link voltage control and Active/Reactive power (PQ) control provide reference currents for inner current controller to generate modulating signal for PWM technique to generate pulses for VSC. DC-link voltage control regulates dc-link voltages to control power whereas active/reactive power control provides direct control of power injection into grid. The controls are designed in synchronous reference frame. Simulation results are provided in order to show the performance of the controllers.