DEVELOPMENT OF A HIGH-GAIN FIVE-LEVEL INVERTER FOR PHOTOVOLTAIC APPLICATIONS WITH WIDE INPUT VOLTAGE OPERATION

Abstract

Photovoltaic (PV) systems experience significant output voltage fluctuations due to changing solar irradiance, temperature, and partial shading conditions, which adversely affect the performance of conventional multilevel inverters. Existing inverter topologies often require multiple DC sources, high component counts, or additional DC-DC boost converters to achieve the desired voltage gain, resulting in increased cost, switching losses, and reduced system efficiency. This paper presents a novel high-boost five-level inverter capable of operating over a wide range of input voltage variations while maintaining a stable AC output suitable for grid-connected and standalone photovoltaic applications. The proposed inverter employs a compact switched-capacitor-based voltage boosting mechanism with optimized pulse-width modulation (PWM) control to achieve high voltage gain without requiring a separate boost converter. The proposed topology reduces the number of power switches, minimizes voltage stress across semiconductor devices, and improves conversion efficiency. Simulation and performance analysis demonstrate that the proposed inverter provides superior voltage boosting capability, low total harmonic distortion (THD), enhanced efficiency, improved power quality, and reliable operation under varying PV input conditions. These characteristics make the proposed converter an effective solution for modern renewable energy systems requiring compact, efficient, and cost-effective power conversion.