Impact of UPFC on Transmission Line Protection
Thesedays, advanced power-electronic equipment technologies or flexible AC transmission systems (FACTS) are paramount for more efficient utilization and control of existing transmission networks.The Unified Power Flow Controller(UPFC), known for its ability of regulating the line power flow quickly and flexibly, can solve the grid power uneven distribution problem.As the first engineering application of Unified Power Flow Controller (UPFC) in china, the demonstration project in the220kV Nanjing western power grid will use the modular multilevel converter (MMC) for construction technology.Through bidirectional control of power flow in the key region it can enhance the ability of power supply in the western power grid.The basic characteristics of UPFC change the impedance parameters of transmission line and have some impacts on the existing relay protection.Combining with the implementation of the project, this paper analyzes the influences of UPFC on the relay protection.Through the research of UPFC external characteristic in various operation conditions, this paper expounds the influences of UPFC on distance and zero-sequence(ZS) protection.This paper paints out same typical influences.For example, when UPFC presents the capacitance characteristics, distance protection may occur same problems such as overrange and wrong direction.When the UPFC presents the inductance characteristic, distance protection sensitivity is reduced.By constructing the UPFC simulation model incorporated in transmission lines, the performance of transmission line relay protection is verified.Finally, relevant suggestion are proposed on the protection configuration, setting calculation and the coordination of UPFC control strategy, it has practical value for the reliable and stable operation of the system with UPFC.
Coordinated control Configuration of settings Distance protection Series transformer PFC Zero-sequence (ZS)protection
Ning Xu Hua Xie Xin Yi Qingchun Zhao Guangwu Dai Xiaotong Zhu Lei Pan
Dispatching and Control Center of State Grid Jiangsu Electric Power Company NR Electric Co., Ltd.
国际会议
南京
英文
50-58
2015-09-21（万方平台首次上网日期，不代表论文的发表时间）