Single Phase Grid Connected Nine Level Quadruple Boost Inverter with Current Control and Active Damping Capability

This study describes a 9-Level Switched-Capacitor Quadruple Boost Inverter (9LSCQBI) for the 1-Φgrid-tied system through L-C-L filter. This inverter can generate a quadruple voltage gain from a single dc source. Compared to prior switched-capacitor inverters, the absence of an H-bridge decreases voltage stress on switches. The recommended inverter can handle inductive loads and accomplish capacitor voltage balancing itself without the use of auxiliary circuits. The L-C-L filter is frequently employed in grid-tied inverters to decrease switching frequency harmonics. Yet, the filter's resonance produces stability concerns, necessitating effective damping. To avoid resonance, one approach is to connect a resistor to the filtering capacitor in series. However, this affects the inverter's efficiency. The proposed method employs current control and an Active Damping (AD) scheme entails incorporating a proportional regulation loop to monitor filter capacitor's current. In which, the grid current is controlled by a Proportional Resonant (PR) controller, whereas AD eliminates L-C-L resonance and preserves stability. Simulation outcomes demonstrate the proposed scheme's efficacy and robustness.