Multi-converters droop control in single-phase microgrid

This paper develops the droop control strategy to connect multiple different types of converters in parallel in an isolated single-phase low voltage microgrid. First, the traditional droop control for low voltage microgrids is explained. Then three different types of converters in a microgrid are described, and different droop equations are proposed for each converter to overcome the line impedance drawback when sharing active power. The new equations also include the priority feature that prioritizes the renewable sources instead of the batteries. Simulations of a modeled microgrid with four converters and two resistive loads are performed. Accurate active power sharing is achieved even with different values of line impedance, the voltage at load bus is regulated, and the functionality of the equations for selecting the priority of generation and the correct power balance to avoid damages in the microgrid elements is verified.