Padé Approximation Based Open Switch Fault Detection For Induction Motor Drive System

Three-phase induction motor drive systems are very prone to critical failures due to open switch faults of the power electronic converter. Monitoring and early fault detection of such failures improves reliability and ensures the safe and continuous operation of the motor drive system. This paper presents a novel simple real-time open switch fault detection method for PWM-VSI fed induction motor drive. The proposed fault detection scheme utilizes the sampled motor stator current which is manipulated using Padé approximation in order to extract the DC component inherently generated due to open switch fault. MATLAB simulations are carried out and results show the effectiveness of the proposed fault detection method during various test cases.