Operation of Three-level Single-Phase Half-Bridge NPC Inverter-Based Shunt Active Power Filter Under Non-Ideal Grid Voltage Condition With Sliding Mode Controller

Abstract

In this paper, a new control method is presented for a single-phase three-level neutral point clamped half-bridge shunt active power filter with the aim of eliminating the grid current harmonics. It is shown that the proposed control method accurately detects the positive-sequence voltage component under distorted grid condition. With this feature, the performance of the single-phase active power filter under distorted grid voltage condition is improved considerably. Furthermore, the imbalance in the capacitor voltages which occurs in the half-bridge topology is eliminated by adding a feedback term to the current control loop. The performance of the proposed control method is verified by simulation results obtained from MATLAB/Simulink.