A hysteresis loop control method for output current of three-phase photovoltaic grid-connected inverters

Abstract

In the design of a three-phase photovoltaic grid-connected inverter system, the control strategy usually adopts hysteresis loop current control. To solve this problem, space vector-asymmetric double hysteresisloop current control method is introduced, which can reduce the switching frequency and the switching loss to a certain extent and realize the grid-connected current power factor close to 1. The simulation models based on the three-phase stationary coordinate system and two-phase stationary coordinate system are built-in Matlab/Simulink simulation platform respectively. The two control strategies are compared and analyzed in terms of grid-connected current and voltage, switching frequency, power factor, etc. The simulation results verify the correctness of the control scheme.