Generalized SVPWM Eliminating Overlap Time for Current Source Converter

Current source converters (CSCs) benefit from using an inductor as the dc link element, which eliminates shoot-through problems and extends their lifespan. However, these converters face a significant challenge known as the arm-open issue. If there is no path for the dc link inductor, a huge voltage spike is induced, which can damage semiconductor devices. Therefore, to prevent the arm-open issue, overlap time is typically required, but the overlap time distorts input and output waveforms. In this study, space vector pulsewidth modulation (SVPWM) that does not require the overlap time for a three-phase current source rectifier/inverter (CSR/CSI) is proposed. The proposed scheme provides a freewheeling path for the dc link inductor by slightly modifying the conventional SVPWM without requiring additional power devices and sensors, thus eliminating the need for overlap time and improving waveforms. The effectiveness of the proposed scheme is verified through theoretical analysis and experimentation.