Fault tolerant control strategy of 3-phase AC-DC PWM converter under multiple open-switch faults conditions

3-phase AC-DC PWM (Pulse Width Modulation) converter has a possibility of open-switch faults due to some trouble of the switching devices and gate drivers. In this case, the converter causes imbalance of the AC input currents and the pulsation of DC-link voltage. This paper proposes fault tolerant control strategy of 3-phase AC-DC PWM converter under multiple open-switch fault conditions. So a detection method of the open-switch faults and fault tolerance methods are suggested according to fault cases. In this paper, two or more switches fault cases are dealt with. Both computer simulation and experimental results verify the usefulness of the proposed fault-tolerant control algorithm.