Fault diagnosis technology based on Wigner-Ville distribution in power electronics circuit

Based on Wigner-Ville distribution similarity, a method of fault diagnosis is proposed for power electronics circuits. After setting up the module time-frequency matrices of Wigner-Ville distribution for all fault signals, the similarities between the module time-frequency matrices of the fault signal and the former standard are then calculated, thus arriving at the diagnosis according to the principle of maximum similarity. The simulation result of fault diagnosis of a thyristor in a three-phase full-bridge-controlled rectifier shows that the method can accurately identify the fault types as well as the location of the fault elements for power electronics circuits, and it has an excellent performance for noise robustness and calculation complexity. Therefore, it is quite practically valuable in the solution to the fault problems for power electronics circuits.