Research on the Transient State Fault Diagnosis of Asynchronous Motors Based on Error Theory

During the normal operation of the asynchronous motor driven system, due to the requirements of commutation, inversion, and other driving factors, as well as the influence of control factors such as starting, stopping, and speed-regulating, the motor will undergo a certain period of transient state. In the transient state, the stator current and voltage of the motor will produce amplitude distortion, the values of which are different from those in the steady state. Although the transient state lasts for a short time, this unpredictable and uncontrolled instantaneous distortion is likely to cause overload. Long term and frequent overloads are easily to cause faults in the motor driven system. In response to the above issues, this article takes a type of thyristor driven asynchronous motor system as the research object, takes the stator voltage and current during the soft start state as the characteristic parameters in the transient state, and proposes a novel fault diagnosis strategy based on the procedure of error theory. The numerical calculation and experimental research based on such new method prove this strategy effective.