Coordination between Substation Area Backup Protection and Flux-Coupling Type Superconducting Fault Current Limiter Considering Network Communications

Since the interactivity, integrality and instantaneity of information communication in smart substation have been improved to higher levels, it can contribute to promote the realization of a centralized type substation area backup protection (SABP), acting as an integrated protection system for whole substation. On the side, in the case that fault current limiters (FCLs) are suggested to be employed for suppressing short-currents to lower degrees where circuit-breakers can interrupt more effectively, the study of the coordination between the SABP and FCLs is meaningful. In this paper, according to a flux-coupling type superconducting fault current limiter (SFCL) proposed by us previously, its integrated application into a real 220kV smart substation with the centralized type SABPs is investigated. The technical characteristics of the SFCL and the SABP are elaborated firstly, and then assuming that the SFCL can be installed into the 220kV smart substation’s different locations, a feasible design strategy for the SABP-SFCL communication network directly affecting both performances is given. Further, regarding the built SABP-SFCL communication network, the network performances including real-time and reliability are evaluated by simulation computation and mathematical analysis. At the end of this article, taken into account the protection algorithm and the SFCL’s current-limiting mechanism, the action coordination mode between them is presented. From the research results, the coordination mode’s validity can be preliminarily confirmed.