Stability Analysis of Two-Stage Single-Phase Converter System Adopting Electrolytic Capacitor-Less Second Harmonic Current Compensator

For the two-stage single-phase converter, including power factor correction (PFC) ac-dc converter and dc-ac inverter, a second harmonic current compensator (SHCC) can be introduced to handle (SHC) for removing undesired electrolytic capacitor. Consequently, becomes multi-converter system. In this paper, stage or in system is categorized into two types terms of control objectives, i.e., bus-voltage-controlled (BVCC) bus-current controlled (BCCC). The SHCC BCCC since its bus-port directly controlled, impedance derived, which affected by SHC reference extracted from them. stability investigated with impedance-based criterion, it found that different when operated as BVCC BCCC. Specifically, only BVCC, unstable; while other cases, certainly stable. applications where virtual resistor realized scheme ensure stability. Finally, PFC fabricated tested verify theoretical analysis.