Power Quality Improvement in Nonlinear Lighting Load Applications Using Shunt Active Power Filter Control

This paper develops an enhanced current control approach for a Three-Phase Four-Wire (3P4W) split-capacitor Shunt Active Power Filter (SAPF) to mitigate current harmonics produced by Compact Fluorescent Lamps (CFLs). A Fuzzy Hysteresis Current Controller (FHCC) and a Modulated Hysteresis Current Controller (MHCC) are proposed to provide the triggering signals for the Insulated-Gate Bipolar Transistors (IGBTs) of the SAPF to ensure improved switching performance and reduced steady-state error near the Shifted Zero-Crossing Area (S-ZCA). The Synchronous Reference Frame (SRF) power theory is adopted for reference current generation. The effectiveness of both techniques, FHCC and MHCC, is evaluated through simulations inMATLAB®/Simulink and validated in real time using the Hardware-in-the-Loop (HIL) platform, especially with the Typhoon HIL-402 device. As both techniques act exclusively for switching gate signal generation techniques and not reference-current extraction methods, the structures are general in nature and are not load-dependent. Comparative analysis with the conventional hysteresis current controller (HCC) demonstrates significant improvements in the reduction of Total Harmonic Distortion (THD) to 1.08% and the overall improvement of power quality without notches in waveforms near zero crossings. The results confirm the robustness and efficiency of the proposed MHCC strategy in the HIL implementation.