Common Mode Voltage Reduction of Single-Phase Quasi-Z-Source Inverter-Based Photovoltaic System

A common mode voltage (CMV) reduction method is proposed for the active power filter (APF) integrated single-phase quasi-Z-source inverter (qZSI) based photovoltaic (PV) power system. The APF integrated qZSI completely compensates the dc-side double-line-frequency (2ω) ripple through the APF capacitor, while maintaining low qZS inductance and capacitance. The proposed method reduces the CMV amplitude to half of that using the traditional sinusoidal pulse width modulation (SPWM). The switching and conduction power losses are analyzed. Simulation and experimental results demonstrate the proposed method reduces CMV without comprising performance and efficiency of the APF integrated single-phase qZSI.