A systematic parameter tuning of PI current controller for LCL-type active rectifiers under unbalanced grid voltage conditions

Abstract

Active rectifiers are widely employed in three-phase electric drive or renewable energy resource systems because of the bidirectional power flow and the power factor correction. This paper proposes a systematic method to determine the parameters for the PI current controllers in active rectifier systems using LCL filter under unbalanced grid faults. The parameters of PI regulators are designed in frequency domain and taking into account the full model of the LCL filter as well as the time delay in control system, which improves the system stability and reliability. The simulation results in MATLAB and hardware-in-the-loop experimental simulation using the HIL 402 device of Typhoon validate the robust and capability of active rectifier in stabilizing the system under different non-ideal conditions of grid voltage