Abstract：The single-phase-to-ground faults account for approximately 80% of all faults in the distribution network, necessitating accurate and reliable fault location to ensure power system security and stability. Due to the influence of different grounding modes, traditional passive location methods based on transient or steady-state features often lack location sensitivity under high-resistance grounding or small fault initial angles, owing to weak characteristic signals. Existing active signal injection methods typically require additional signal-injection equipment and are limited by monotonous signal features and a lack of anti-interference capability. Considering the development of the double-high power system, a reliable identification of the section affected by a ground fault can be achieved by a characteristic controllable current signal generated by the power electronics employed to switch the damping resistor in the arc-suppression coil. This method requires no additional signal-injection equipment, maintains identification accuracy under interference, and eliminates the need for potential transformers at terminal units. When the single-phase-to-ground fault enters a steady state, the damping resistor is periodically switched for short durations by controlling the delay triggering angle δ of the anti-parallel thyristor applied to the damping resistor in the arc suppression coil, generating a transient current disturbance in the zero-sequence circuit. The characteristic signal is then accurately extracted from the zero-sequence current—which contains power frequency components and background noise—by employing a full-cycle subtraction combined with a multi-signal polarity correction mean algorithm. Furthermore, establishing the zero-sequence harmonic impedance at the beginning and end of the section, and constructing the phase information indicator θav based on the characteristic frequency band. Based on the indicator above, the double-end and single-end section location criteria are established to cope with the various operating conditions. Results from Matlab simulations based on the topology of an actual 10? kV distribution network line, as well as simulated experiments employing the method of reducing the entire network voltage, indicate that the disturbance signal is concentrated in the low-frequency band below 100? Hz, and the signal strength increases significantly with the increase of δ. Besides, the phase difference indicator θcr between the sending and receiving ends of the faulted section remains consistently and significantly positive, therefore the faulted section can be identified accurately in both the simulation tests and simulated experiments. Sensitivity analysis confirms that the θcr of the faulted section remains more than 10° larger than that of the healthy sections under the combined effects of high fault resistance, long cable lines, and measurement errors caused by asynchronism. Furthermore, comparative analysis verifies that the proposed method can accurately locate the fault under conditions of a fault inception angle of 5° and a fault resistance of 2 kΩ, while the existing methods based on transient reactive power or current increment exhibit abnormal location results. According to the analysis above, the following conclusions can be drawn: (1) The proposed section location method generates distinct and controllable signal characteristics, which facilitates the detection and extraction of fault signals under the interference of factors such as fault resistance. (2) The variation in the zero-sequence phase-frequency characteristics of the section can be obtained to determine the faulted section by utilizing the generated current signal, eliminating the need for voltage measurement data. (3) The proposed method identifies the faulted section based on changes in the zero-sequence phase-frequency characteristics, a criterion that is independent of the grounding fault type and is minimally affected by fault location and resistance. (4) The signal strength affects the accuracy and synchronization of the signals detected at each terminal, which in turn impacts the precise acquisition of the difference in zero-sequence phase-frequency characteristics between the sending and receiving ends of the section. The signal strength can be increased by controlling δ.
[1] 刘畅宇, 王小君, 张大海, 等. 融合时空图信息的配电网故障区段定位及可解释性分析方法[J]. 电工技术学报, 2026, 41(5): 1623-1636. Liu Changyu, Wang Xiaojun, Zhang Dahai, et al.Research on fault section location method in distribution networks integrating spatio-temporal graph information and interpretability[J]. Transactions of China Electro-technical Society, 2026, 41(5): 1623-1636. [2] 张健磊, 高湛军, 陈明, 等. 考虑复故障的有源配电网故障定位方法[J]. 电工技术学报, 2021, 36(11): 2265-2276. Zhang Jianlei, Gao Zhanjun, Chen Ming, et al.Fault location method for active distribution networks considering combination faults[J]. Transactions of China Electrotechnical Society, 2021, 36(11): 2265-2276. [3] 王秋杰, 李达, 谭洪, 等. 考虑灾前加固信息的配电网故障区段定位研究[J]. 电工技术学报, 2026, 41(5): 1623-1636. Wang Qiujie, Li Da, Tan Hong, et al.Research on fault section location in distribution networks considering pre-disaster reinforcement information[J]. Transactions of China Electrotechnical Society, 2026, 41(5): 1623-1636. [4] 薛永端, 徐丙垠, 冯祖仁, 等. 小电流接地故障暂态方向保护原理研究[J]. 中国电机工程学报, 2003, 23(7): 51-56. Xue Yongduan, Xu Bingyin, Feng Zuren, et al.The principle of directional earth fault protection using zero sequence transients in non-solid earthed network[J]. Proceedings of the CSEE, 2003, 23(7): 51-56. [5] 李林, 高厚磊, 袁通, 等. 基于零序突变量的配电网单相接地故障检测与定位方法[J]. 电力系统自动化, 2025, 49(15): 157-167. Li Lin, Gao Houlei, Yuan Tong, et al.Detection and location method of single-phase-to-ground fault in distribution network based on zero-sequence transient fault component[J]. Automation of Electric Power Systems, 2025, 49(15): 157-167. [6] 刘健, 倪建立, 杜宇. 配电网故障区段判断和隔离的统一矩阵算法[J]. 电力系统自动化, 1999, 23(1): 31-33. Liu Jian, Ni Jianli, Du Yu.A unified matrix algorithm for fault section detection and isolation in distribution system[J]. Automation of Electric Power Systems, 1999, 23(1): 31-33. [7] 梅念, 石东源, 杨增力, 等. 一种实用的复杂配电网故障定位的矩阵算法[J]. 电力系统自动化, 2007, 31(10): 66-70. Mei Nian, Shi Dongyuan, Yang Zengli, et al.A practical matrix-based fault location algorithm for complex distribution network[J]. Automation of Electric Power Systems, 2007, 31(10): 66-70. [8] 邓丰, 李鹏, 曾祥君, 等. 基于D-PMU的配电网故障选线和定位方法[J]. 电力系统自动化, 2020, 44(19): 160-167. Deng Feng, Li Peng, Zeng Xiangjun, et al.Fault line selection and location method based on synchrophasor measurement unit for distribution network[J]. Auto-mation of Electric Power Systems, 2020, 44(19): 160-167. [9] 王晓卫, 王雪, 王璐, 等. 基于矩阵变换与模态分析的电缆型配电网单相接地故障区段定位[J]. 电工技术学报, 2025, 40(15): 4845-4859. Wang Xiaowei, Wang Xue, Wang Lu, et al.Single-phase grounding fault section location of the distribution cable networks based on matrix transformation and mode analysis[J]. Transactions of China Electro-technical Society, 2025, 40(15): 4845-4859. [10] 李宗博, 崔一嘉, 王昊晴, 等. 含逆变型分布式电源的配电网馈线终端告警信息校正及故障定位方法[J]. 电工技术学报, 2025, 40(4): 1268-1286. Li Zongbo, Cui Yijia, Wang Haoqing, et al.Method of alarm information correction and fault location for distribution network with inverter-interfaced distributed generation[J]. Transactions of China Electrotechnical Society, 2025, 40(4): 1268-1286. [11] 张明一, 孙元章, 黎雄, 等. 改进时域反演算法在配电网故障定位中的应用[J]. 电力系统自动化, 2021, 45(15): 101-108. Zhang Mingyi, Sun Yuanzhang, Li Xiong, et al.Application of improved time reversal algorithm in fault location for distribution network[J]. Automation of Electric Power Systems, 2021, 45(15): 101-108. [12] 吉兴全, 张朔, 张玉敏, 等. 基于IELM算法的配电网故障区段定位[J]. 电力系统自动化, 2021, 45(22): 157-166. Ji Xingquan, Zhang Shuo, Zhang Yumin, et al.Fault section location for distribution network based on improved electromagnetism-like mechanism algorithm[J]. Automation of Electric Power Systems, 2021, 45(22): 157-166. [13] 黄南天, 程铎, 蔡国伟. 基于改进时空图神经网络的高渗透率有源配电网故障定位[J]. 电力系统自动化, 2025, 49(10): 112-122. Huang Nantian, Cheng Duo, Cai Guowei.Fault location for active distribution network with high penetration rate based on improved spatio-temporal graph neural network[J]. Automation of Electric Power Systems, 2025, 49(10): 112-122. [14] 尹力, 孔令昌, 王冠华, 等. 基于负序电压变化量的灵活接地配电网永久性单相接地故障定位[J]. 电力自动化设备, 2023, 43(1): 83-89, 99. Yin Li, Kong Lingchang, Wang Guanhua, et al.Permanent single-phase grounding fault location in flexible grounding distribution network based on negative-sequence voltage variation[J]. Electric Power Automation Equipment, 2023, 43(1): 83-89, 99. [15] Wang Peng, Chen Baichao, Zhou Hong, et al.Fault location in resonant grounded network by adaptive control of neutral-to-earth complex impedance[J]. IEEE Transactions on Power Delivery, 2018, 33(2): 689-698. [16] Chen Baichao, Yu Na, Chen Bo, et al.Fault location for underground cables in ungrounded MV distribution networks based on ZSC signal injection[J]. IEEE Transactions on Power Delivery, 2021, 36(5): 2965-2977. [17] Wang Peng, Zhou Hong, Chen Baichao, et al.Fault location method in resonant grounded networks based on distributed modulation and compensation adjustment[J]. IEEE Transactions on Power Delivery, 2019, 34(5): 1938-1947. [18] Milioudis A N, Andreou G T, Labridis D P.Detection and location of high impedance faults in multiconductor overhead distribution lines using power line communication devices[J]. IEEE Transa-ctions on Smart Grid, 2015, 6(2): 894-902. [19] 宋国兵, 王婷, 张保会, 等. 利用电力电子装置的探测式故障识别技术分析与展望[J]. 电力系统自动化, 2020, 44(20): 173-183. Song Guobing, Wang Ting, Zhang Baohui, et al.Analysis and prospect of detective fault identification technologies using power electronic device[J]. Automation of Electric Power Systems, 2020, 44(20): 173-183. [20] 李海锋, 张正刚, 梁远升, 等. 基于谐波信号注入的含逆变型分布式电源配电网电流差动保护[J]. 电力系统自动化, 2023, 47(22): 120-128. Li Haifeng, Zhang Zhenggang, Liang Yuansheng, et al.Current differential protection for distribution network with inverter-interfaced distributed generat based on injection of harmonic signal[J]. Automation of Electric Power Systems, 2023, 47(22): 120-128. [21] 邱关源. 电路[M]. 5版. 北京: 高等教育出版社, 2006. [22] 孙波, 孙同景, 薛永端, 等. 基于暂态信息的小电流接地故障区段定位[J]. 电力系统自动化, 2008, 32(3): 52-55. Sun Bo, Sun Tongjing, Xue Yongduan, et al.Single phase to ground fault section location based on transient signals in non-solidly earthed network[J]. Automation of Electric Power Systems, 2008, 32(3): 52-55. [23] 明志强, 许虎. 经消弧线圈接地系统的中电阻快速选线方法[J]. 电网技术, 2009, 33(12): 112-114. Ming Zhiqiang, Xu Hu.Fast line selection method of medium resistance in grounding system via arc suppression coil[J]. Power System Technology, 2009, 33(12): 112-114.
2026, Vol. 41 
