Integrated wide area protection and control for power grid security

The traditional “three defense lines” for power systems are based on local information and static protection & control strategy, which are not suitable to modern largescale power systems. In order to improve the security of UHV hybrid power grids, the Integrated Wide Area Protection & Control (IWAPC) is proposed in this paper by applying the new technologies of synchronized high-speed communication, which integrates “three defense lines” and promotes existing wide area protection only for security control. The IWAPC is the hierarchical protection and control system which provides the protection and control for wide area power networks to improve their reliability and security. It is divided into three levels, the local bay level, the substation integrated protection level and the wide area protection level. The wide area realtime protection and control information platform is the most important part of the IWAPC, which is based on a synchronized wide area communication network. The key technologies and new development trends include network topology analysis, wide area backup protection, wide area intelligent reclosing, wide area load shedding, wide area auto-switching, overload cutoff and transfer, transmission section protection, intelligent system splitting and dynamic stability control. It cannot only integrate three lines of defense for power system protection and control, but also improve security of the power grid.