A New Technique for Online Open Switch Fault Detection and Location in Single-phase Pulse Width Modulation Rectifier

Open switch fault detection in the single-phase pulse width modulation (PWM) rectifier using line current analysis technique is very applicable, but no-fault detection at high switching frequency is the main drawback of this technique. In this paper, a new online diagnosis technique for detection and location of open switch fault in the single-phase PWM rectifier is proposed. The proposed diagnosis method is based on instantaneous input voltage of the rectifier analysis. The proposed method can detect the fault in half of the power frequency under high switching frequency and load conditions. Simulation results showed the proposed technique can detect and locate all open switch faults at any switching frequency under different load conditions. In addition, the second-order output filter that is necessary for line current technique can be removed in the proposed technique.