A Novel Topology and Performance Evaluation of a Three-Phase Switched Capacitor Quadruple Gain Multilevel Inverter for PV Systems

Abstract

Conventional switched capacitor boost-multilevel inverters have been widely adopted in solar energy systems and electric vehicles, but their performance is constrained by limited voltage gain, increased switch count, and capacitor voltage imbalance. To mitigate these drawbacks, this paper proposes three phase a single input switched capacitor based quadruple gain multilevel inverter (SCQGMLI) topology capable of generating nine voltage levels using a compact structure comprising only nine switches, two diodes, and two capacitors. The proposed switched capacitor structure provides inherent voltage boosting by efficiently transferring and stacking the stored capacitor energy, thereby significantly reducing reliance on high voltage DC sources. A multi carrier level shifted phase disposition pulse width modulation (MC-PDPWM) strategy is developed to maintain capacitor voltage equilibrium and reliable switching operation. The advantages of the proposed SCQGMLI are demonstrated through an extensive evaluation with recently developed multilevel inverter configurations. The proposed system performance is analysed using MATLAB/Simulink based analysis. Furthermore, hardware in the loop (HIL) validation is performed with the support of the OPAL-RT OP5700 real time platform to experimentally verify the effectiveness and practicality of the proposed configuration.