A Novel Single-Phase Three-Level Dual-Buck Inverter

This article proposes a new single-phase three-level dual-buck inverter. The topology is derived from a simplified neutral-point clamped inverter that includes fewer active switches. The advantages of the proposed inverter are no shoot-through worries and no reverse recovery issue of the body diode of the power metal-oxide-semiconductor field-effect transistor compared with the conventional inverter; therefore, a high-reliability inverter can be achieved. The operation modes and pulsewidth modulation technique are analyzed in detail. Additionally, a switching scheme is proposed to balance and reduce the direct-current-link capacitance. A 1.4-kW prototype was built and tested to validate the theoretical analysis of the proposed converter.