A Fault-Tolerant Common-Ground Based Five-Level Inverter for Photovoltaic Applications

Common-ground switched-capacitor-based multilevel inverters are gaining attention due to their low leakage current and increased voltage gain in photovoltaic applications. However, it allows a few redundant switching states while generating multilevel output, where the failure of any switch may cause the whole system to shut down. Therefore, this article proposes a fault-tolerant common-ground-based five-level inverter with static and dynamic boosting features. The capacitors in the circuit are connected across the switching devices to realize static boosting two times and maintain voltage balance in a fundamental switching cycle. Meanwhile, the input-side boost converter helps to dynamically boost the input voltage and minimize the inrush current drawn from the supply. Also, the redundant switches and reconfigured switching strategy make the suggested circuit fault-tolerant. The proposed inverter requires a few switching components to realize multilevel output, voltage boosting, and fault-tolerant operation. A thorough simulation and experimental studies have been conducted to validate the proposed inverter's capabilities during single and multiple switch faults. A detailed reliability analysis and comparative study demonstrate the effectiveness of the suggested inverter.