Quantitative broken rotor bar fault detection for closed‐loop controlled induction motors

Abstract

In an induction motor with broken rotor bars, stator currents contain fault‐related components. The fault information propagates to voltages when the motor is in a closed‐loop control. The control has an effect on the currents and voltages. Relying solely on the currents or voltages is difficult to obtain an accurate detection and quantification of the fault. A new online diagnosis method, which takes both currents and voltages into consideration, is proposed in this study. A fault severity factor is proposed to evaluate the extension of the fault, which is almost independent of the control parameters. Furthermore, the method can be applied to different control strategies. The effectiveness and robustness of the proposed method have been validated by experimental results.