Fault Diagnosis and Tolerant Control for Sensors of PWM Rectifier Under High Switching Frequency

This paper considers the digital realization of fault diagnosis (FD) and fault tolerant control (FTC) method for both catenary current and DC-link voltage sensor of the PWM rectifier under high switching frequency. A novel state observer is designed, which plays a key role in the FD and FTC algorithms and facilitates their digital implementation. The FD algorithm consists of residual calculation and comparison between residuals and the corresponding thresholds. The FTC technique is realized by control system reconfiguration that replaces the wrong measured value with output of the state observer. Results of simulation experiments confirm the feasibility and superiority of the proposed method.