Optimal control for shunt active power filter based on adaptive-hysteresis controller and droop controller

This paper proposes an optimal control method with adaptive-hysteresis controller (AHCC) and droop controller for shunt active power filter (SAPF). The voltage source inverter (VSI) gate switching signals are generated by adaptive-hysteresis current controller, in which the bandwidth is modulated with the system parameters to maintain the modulation frequency nearly constant. The droop controller is used to optimize the dc-side reference voltage for PI control under different grid or load conditions. A three-phase three-wire SAPF system is simulated in MATLAB/Simulink to validate the optimal control method and evaluate the effect of the harmonic compensation. Simulation results verify that SAPF with this control method has better dynamic compensation characteristic.