Analysis and Suppression of Commutation Overlap-Time for Bidirectional Switch-Based Current Source Converter

Safe and reliable current commutation has always been essential for the current source converter (CSC), especially those based on the newly released wide-bandgap bidirectional switch. However, existing commutation strategies suffer from either the inevitable commutation overlap time or the fatal short circuit, obstructing their applications. To address this issue, this paper firstly presents a comprehensive analysis of overlap time, a safe and reliable commutation strategy is subsequently proposed. Its implementation and characteristics have been developed and presented in detail. The effectiveness of this commutation strategy has been verified in a 3 kW CSC system working as an inverter.