Dictionary Based Three-phase Driver MOSFET Cascading Fault Diagnosis

MOSFET is widely used in motor driver because of its high switching frequency, but it often fails for many reasons which may results in driver faults. This paper presents a diagnosis method based on the output characteristic dictionary for open/short circuit mixed cascading faults of the three-phase driver. The small signal model is used to quantitatively analyze the fault influence, and a multi-value fault dictionary is constructed based on the time-frequency domain characteristics of online measurable signals such as output current and output voltage. Based on the numerical simulation method, the typical single faults and cascading faults are simulated and injected, which proves the effectiveness of this developed method.