Current behavior-based open-switch fault on-line diagnosis of inverters in PMSM drive systems

The power switches of inverters in permanent magnet synchronous motor (PMSM) drive systems are prone to breaking down and may cause open-circuit fault (OC) due to high electrical and thermal stresses. This paper presents an OC fault diagnostic method of inverters in closed-loop controlled PMSM drive systems based on current behavior. A new detection scheme indicating the relationship between the OC fault and the current behavior variation are constructed. This scheme has the ability to detect the fault within one eighth of a current cycle. Meanwhile, a key transition model including 2 faulty states and 1 recovery state for the location of single -switch and double-switch OC faults are proposed for the first time. A total of 21 kinds of OC faults can be rapidly located. Experimental results validate that the proposed method has the advantage of fast fault diagnosis, ac-curate fault switch location and good robustness.

Automated summary

This paper proposes a fault diagnostic method for OC faults in closed-loop controlled PMSM drive systems based on current behavior. The method can rapidly and accurately locate the fault position and has good robustness.