A novel substation area backup protection for smart substation

This paper proposes a new scheme of substation area backup protection system based on substation area range of information. A configuration scheme of relay protection in smart substation was proposed firstly, the structure of substation area backup protection (SABP) was introduced, the information matrix of SABP which can reflect the substation topology was established, the protection algorithm of SABP was proposed, the fault-tolerance performance of the proposed protection scheme was also analyzed. According to the analysis of fault direction information, fault current differential information, as well as the information matrix, the SABP can carry out fault location and make a reasonable tripping strategy. The result of case studies shows that the proposed protection algorithm can implement backup protection and circuit breaker failure protection for each electrical element inside smart substation, and has good adaptability to disconnection fault of CT.