Open circuit fault diagnoses for power electronic converters

Reliability of power electronic systems is of paramount importance in industrial, commercial, aerospace, and military applications. Faults in power converters are classified as short circuit faults, open circuit faults, and degradation faults. Short circuits (S-C) in most cases cause an overcurrent condition that is readily detected and acted upon by standard protection systems. However, open circuit (O-C) faults often do not trigger fault protection, but rather cause system malfunction or performance degradation. Since the standard protection system may not detect the open circuit faults, O-C fault diagnosis becomes critical for power converter. This paper presents new methods for O-C fault detection, localization, and diagnosis for small wind power converters that consist of three subsystems: the three phase rectifier, the dc-dc converter, and the single-phase inverter.