A sinusoidal pulse width modulation (SPWM) technique for capacitor voltage balancing of nested I-type four-level inverter

Abstract

Abstract This article proposes a new control method based on a sinusoidal-width modulation (PWM) scheme to control the voltage of the I-type inverter. The four-stage FC type I inverter has fewer switches and components than the classic and advanced four-stage inverter, making this chassis attractive for high-performance high voltage applications. This structure was designed and studied assuming a constant current source rather than a flying capacitor. In this circuit, a medium power single phase rectifier is designed to balance the voltage of the flying capacitor. The efficiency and qualification of the proposed control methods are evaluated experimentally under constant and temporary conditions and at various modulation rates and loads. Experimental results show the effectiveness of the control method developed to control the capacitor voltage.