Secondary Information Fault-tolerance Method for Smart Substation Based on Residuals of Measurement Equations

This paper presented a method of fault-tolerance for secondary-system information in smart substations. It was to solve the problem of information redundancy. This article drew on a method of state estimation on the primary-system and used the calculation of measurement-equation residuals to identify and eliminate bad data to complete the information fault-tolerance function. The diagrams illustrated the process of information interaction in the secondary-system, and introduced the configuration mode of relay protection in smart substations. Through simulation and verification, using the method of residual identification to perform protection fault-tolerance can effectively prevent the protection against misoperation caused by bad data, improve the credibility of data, and promote the reliability of the protection.