Output error voltages - a first method to detect and locate faults in matrix converters

This paper proposes a first diagnostic technique for the detection and location of open-circuit faults in the power switches of matrix converter drives. The proposed method relies on the continuous monitoring of the amplitude of the three output error voltages and works in a two-stage approach. In a first stage, if an open-circuit fault arises in the power converter, the error voltage associated with the output phase which contains the faulty element will rise considerably, hence triggering the indication of the fault. In a second stage, the exact location of the faulty element across the faulty phase will be done by monitoring the output error voltage of that phase when the reference input current and output voltage vectors lie within specific combinations of sectors, according to a table constructed for this purpose. The simulation results demonstrate that the proposed diagnostic technique is effective in the detection and location of the faulty switch in a period of time as fast as one-eighteenth of the electrical period of the supply voltage of the converter and can be used independently of the type of load, both in steady-state and transient conditions.