Analysis and Design of Impulse-Commutated Zero-Current-Switching Single-Inductor Current-Fed Three-Phase Push-Pull Converter

Impulse commutation obtains zero current commutation of devices in a circuit with a short resonance impulse using a simple resonant tank. This concept has been studied, extended, and implemented for a three-phase push-pull current-fed single-inductor topology to achieve soft commutation and device voltage clamping solving the traditional issue of device turn-off voltage overshoot. The push-pull topology is attractive owing to single inductor, all common source devices connected to common supply ground, and reduced gate driving requirements. Detailed operation, analysis, and design of this topology have been reported with impulse commutation. With a small resonant tank and partial resonance, impulse commutation procures merits of voltage clamping, low circulating current, and load adaptive zero-current switching of the devices. Variable-frequency modulation regulates load voltage and maintains the impulse commutation with source voltage variation. Experimental results on a 1-kW proof-of-concept hardware prototype are demonstrated to observe the operation, performance, and verify the proposed concept and claims.