Incipient Voltage Sensor Fault Isolation for Rectifier in Railway Electrical Traction Systems

This paper proposes a dc voltage incipient sensor fault isolation method for single-phase three-level rectifier devices in high-speed railway electrical traction systems. Different incipient fault modes characterizing locations and incipient fault types are parameterized nonlinearly by unknown fault parameters. A new incipient fault isolation method is developed by combining sliding mode technique with nonlinear parametrization adaptive estimation technique. A bank of particular adaptive sliding mode estimators is proposed, which facilitates to derive new isolation residuals and adaptive threshold intervals. The isolability is studied, and the isolable sufficient condition is derived using new functions. For the practical electrical traction system in CRH2 (China Railway High-Speed 2), simulation and experiment based on TDCS-FIB (a software) are presented to verify the effectiveness and feasibility of the proposed method.