Research on faults diagnosis methods of induction motors with variable frequency driver system

In the variable frequency driver system of induction motor,the DC-side current of converters and the AC-side current of rectifiers are analytically analyzed using switching functions of converters and rectifiers when induction motors would be in fault state.The transmission rules of faults characteristic information in driver system were derived,and the fault features frequency components corresponding to induction motor faults were acquired in the spectral of the DC-side current of converters and the AC-side current of rectifiers.In terms of the conlusion as mentioned,take the fault diagnosis of the broken rotor bars faults as an example to explain the transmission rules of faults characteristic information based on the driver system.Simulation calculation and experimental results show that the theoretic analysis are correct,and the research provides theoretic foundation for diagnosing motor faults based on the rectifier's AC-side current spectral analysis technology.