Impact of Space Vector Selection and Input Displacement Angle on Switch Voltage Stress of Current Source Rectifier

Three-phase current source rectifier is concerned due to its flexible output voltage regulation, high reliability, and fast dynamic response. Excessive voltage stress on the switch will increase the cost of the rectifier and reduce the reliability of the system. Therefore, it is essential to optimize the voltage stress on the switch. In this letter, the voltage stress of the switch caused by each current vector in space vector modulation (SVM) is analyzed. Then, the vectors with low-voltage stress are selected for combination to reduce the voltage stress of the switch without changing the topology. In addition, the vectors are reoptimized considering the effects of displacement angle. The reoptimized SVM can reduce the voltage stress by up to 13% under the leading or lagging power factor operation. Furthermore, the dc-link current ripple and modulation index range of different modulation methods are compared, and the effectiveness of the proposed modulation schemes are verified by experiments.