1. 南京南瑞继保电气有限公司, 江苏省南京市 211102; 2. 南瑞集团有限公司(国网电力科学研究院有限公司), 江苏省南京市 211106; 3. 常州博瑞电力自动化设备有限公司, 江苏省常州市 213025
1. NR Electric Co., Ltd., Nanjing 211102, China; 2. NARI Group Corporation(State Grid Electric Power Research Institute), Nanjing 211106, China; 3. BR Electric Power Electronics Co., Ltd., Changzhou 213025, China
With the continuous development of power grid capacity, the short-circuit current of the power grid could be very large in some certain districts, which may seriously harm the stability and safe operation of the system. A high voltage fast-switching fault current limiter with multiple breakers in series is proposed. The equipotential of driving mechanism and fracture is realized through isolation transformer, the insulated pull rod can be cancelled by using the “one-drive-two” electromagnetic repulsion mechanism, which realizes quick opening and closing. Meanwhile, the problem that the fault current limiter powered by capacitive voltage transformer(CVT)is not able to be open or close when the system is not charged is solved as well. In addition, the parameters of the repulsion mechanism with two coil series connected structure are optimized and designed by using 3D finite element simulation, the stray capacitances with multiple breakers between switches and the ground are extracted, and then the equalizing capacitances of fractures are installed to guarantee the uniformity of voltages on eight switches. Finally, a testing circuit based on LC oscillation is built to verify the principle of proposed 220 kV fault current limiter with multiple breakers in series. The voltage sharing characteristics of fast-switching with multiple breakers are obtained during the dynamic process of transition of the short-circuit current to the current limiting reactor. Furthermore, the opening and closing synthesis experiments of fast switch of the prototype with different arcing time are carried out. The testing results show that the fast-switching can switch the short-circuit current of high DC component in a cycle.
LUY Wei, LIU Yunfei, ZHOU Qiwen,et al.Fast-switching High Voltage Fault Current Limiter with Multiple Breakers[J].Automation of Electric Power Systems,2019,43(23):234-239. DOI:10.7500/AEPS20190415005.