An Optimized PWM Pattern for Three-Phase Current Source Rectifier With Fault-Tolerant of Short-Circuit in Bridge Legs

Compared to the three-phase voltage source rectifier (VSR), the three-phase current source rectifier (CSR) generally has higher reliability. The bridge legs of the three-phase CSR are composed of switching devices in series with diodes. When short-circuit faults occur in the switching devices of the bridge legs, the conventional space vector pulse width modulation (SVPWM) strategy leads to the input currents distortion and the output voltage instability of the three-phase CSR. The influence of short-circuit in bridge legs is analyzed in this brief, and then an optimized pulse width modulation (PWM) pattern is proposed. The proposed PWM pattern improves the quality of input currents and ensures stable output voltage under short-circuit condition. Finally, the correctness and effectiveness of the proposed pattern are verified by a 1000W experimental prototype.