Generalized Static Fault Diagnosis for Multi-phase Inverter in Motor Drives

Abstract

This paper proposes a generalized static fault diagnosis method, which is suitable for multi-phase inverter used in motor drives. The short or open circuit fault diagnosis is based on a simple monitoring network just consisted of two current limit resistors and two photocouplers. Therefore the proposed method could keep the system safety under the condition of only weak current passing through the network. According to the rules in fault diagnosis, the faults could be detected and classified by the output signals of monitoring network. Different with the past approaches, the aforementioned method requires that the fault self-test must be completed before system running. And the output ports of monitoring network can be directly connected with sample device and farther sent to the computer/micro-controller by communication. Besides, the monitoring network has the feasibility to be applied in any multi-phase system without structural change. In the end, simulation and experimental results of short and open circuit faults are provided to validate the effectiveness of the proposed diagnosis.