Sensitive and reliable detection of broken rotor bar fault in induction motors

This paper develops a sensitive and reliable detection scheme for broken rotor bar fault in induction motors, taking into account the intrinsic asymmetry, air-gap eccentricity and rotor misalignment. Firstly, numerical simulation along with related experiments of broken rotor bar fault are performed successfully. Secondly, by thoroughly analyzing the simulation and experiment results, a series of interesting highlights, which could help improve the sensitivity and reliability of broken rotor bar fault detection in actual field, are revealed explicitly. Finally, a novel scheme to detect broken rotor bar fault, which perfectly blends continuous subdivision Fourier transform, self-adaptive filter, rotor slot harmonics based slip estimation and detection threshold self-tuning technique together, and thus possesses high-sensitivity and high-reliability, is proposed in this paper. Fault detection instances in laboratory demonstrate that the presented scheme is valid and effective.