智能电网教育部重点实验室, 天津大学, 天津市 300072
Key Laboratory of the Ministry of Education on Smart Power Grids, Tianjin University, Tianjin 300072, China
The propagation characteristics of fault traveling wave on line commutated converter-voltage source converter(LCC-VSC)high voltage direct current(HVDC)transmission line are different from those line commutated converter based HVDC(LCC-HVDC)or voltage source converter based HVDC(VSC-HVDC)transmission lines. Aiming at LCC-VSC HVDC transmission line, the refraction and reflection processes of traveling wave and the frequency-variation characteristic of the reflection angles at both boundaries of lines are analyzed, the reasonable installation side for the single-end fault location device is determined, and a novel location principle of combined single-end fault is proposed. Firstly, the location method of natural frequency fault whose accuracy is slightly lower is utilized to roughly locate the fault point and obtain approximate arrival time of the first reflected wave from the fault point. Then, based on the symmetry between the arrival time of the reflected wave head from the fault point and that from the opposite bus of line, the precise arrival time of these two reflected waves are found by matching in traveling wave propagation sequence diagram. Finally, the fault point is accurately located with the arrival times of the initial traveling wave, the first reflected wave from the fault point and that from the opposite bus of line. The simulation results show that the introduction of the natural frequency method effectively avoids the location error caused by the inaccurate discrimination between the first reflection wave from the fault point and that from the opposite bus of line, and the proposed method can accurately locate the fault point on the transmission lines of the LCC-VSC HVDC system.
ZHANG Yanxia, WANG Haidong, LI Ting,et al.Combined Single-end Fault Location Method for LCC-VSC Hybrid HVDC Transmission Line[J].Automation of Electric Power Systems,2019,43(21):187-194. DOI:10.7500/AEPS20181121006.