能量积分型有源配电网无功电流差动保护

doi:10.19595/j.cnki.1000-6753.tces.250119

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Abstract A significant amount of renewable energy is integrated into the distribution network in the form of inverter-based distributed generators (IBDGs), which transform the traditional distribution networks into active distribution networks. The integration of numerous distributed generators (DGs) has increased the complexity of topology and fault characteristics in active distribution networks. Specifically, the weak fault current contribution of IBDGs and T-connected unmeasurable branch loads have reduced the sensitivity of traditional current differential protection in active distribution networks, sometimes even causing maloperation. To address these issues, an energy integral based reactive current differential protection method is proposed.
Firstly, the reactive differential current is defined as the sum of the reactive components of fault currents at both sides of the protected feeder. Based on the distinct characteristics of nonlinear energy integral value of reactive differential currents during internal and external faults, an energy integral based reactive current differential protection criterion is established. The nonlinear energy integral value is sensitivity to the amplitude and frequency variations of reactive differential current. The energy value is zero when either amplitude or frequency becomes zero. Under normal operation or external faults, the reactive differential current remains zero or consists of a DC component (the frequency of DC components is zero), resulting in an energy integral value equaling zero. However, during internal faults, the reactive differential current contains decaying power frequency components or double power frequency components, leading to significantly large energy integral values. The unbalanced reactive differential current caused by unmeasurable T-connected branch loads manifests as a DC component, and its energy integral value equals zero. In contrast, the reactive differential current resulting from internal short-circuit faults contains decaying power frequency components or double power frequency components, yielding a significantly large energy integral value. This distinction enables the proposed method to be applicable to feeders with unmeasurable T-connected branch loads while requiring only current information from both ends of the feeder.
Subsequently, a 10 kV active distribution network simulation model was built in PSCAD. The simulation results show that the proposed method effectively mitigates the impact of crossing currents on current differential protection during internal high-impedance faults. Additionally, it addresses the challenges of distinguishing unbalanced currents caused by unmeasurable T-connected branch loads from fault currents due to internal short-circuits. This approach reliably discriminates internal and external faults and exhibits certain ability to withstand data synchronization errors. Furthermore, two smart terminal prototypes with 5G communication capabilities were developed, and a RTDS closed-loop testing system was established for hardware-in-the-loop validation. The experimental results demonstrate that the fault clearance time of the prototype ranges from 64.6 ms to 79.2 ms. With effective communication, the prototypes achieved 100% accuracy in short-circuit faults identification.
The simulations and hardware-in-the-loop experiments yield the following conclusions: (1) The proposed method only requires current information from both sides of the protected feeder and is applicable to feeders with unmeasurable T-connected branch loads while accurately identifying all types of internal and external short-circuit faults. (2) Compared with traditional current differential protection, the proposed method demonstrates superior ability to withstand transition resistance and reliably identifies high-impedance faults even when crossing currents exist in the protected feeder. (3) The method remains effective regardless of power source characteristics, showing consistent sensitivity in identifying short-circuit faults in active distribution networks with IBDGs, synchronous-based DGs (SBDGs), or even without DGs integration.

Key words： Differential protection reactive current energy integral unmeasured branch loads protection prototype 5G communication

Received: 17 January 2025

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TM77

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	Zheng Xincheng
	Zou Guibin
	Lu Zhe
	Wang Kaiqi
	Li Qingquan

Cite this article:

Zheng Xincheng,Zou Guibin,Lu Zhe等. Energy Integral Based Reactive Current Differential Protection for Active Distribution Networks[J]. Transactions of China Electrotechnical Society, 2026, 41(3): 949-960.

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https://dgjsxb.ces-transaction.com/EN/10.19595/j.cnki.1000-6753.tces.250119 OR https://dgjsxb.ces-transaction.com/EN/Y2026/V41/I3/949

[1] 韦明杰, 王聪博, 余越, 等. 适用高比例分布式光伏接入的配电网多级保护优化配置方案[J]. 电力系统自动化, 2023, 47(22): 55-65.
Wei Mingjie, Wang Congbo, Yu Yue, et al.Optimal configuration scheme of multi-staged protection in distribution network for integration of high proportion of distributed photovoltaic[J]. Automation of Electric Power Systems, 2023, 47(22): 55-65.
[2] 乔一达, 吴红斌, 吴通华, 等. 含逆变型分布式电源的配电网分区域电流保护[J]. 电工技术学报, 2022, 37(增刊1): 134-144.
Qiao Yida, Wu Hongbin, Wu Tonghua, et al.A partitioned current protection scheme of distribution network with inverter interfaced distributed generator[J]. Transactions of China Electrotechnical Society, 2022, 37(S1): 134-144.
[3] 李君, 何敏, 黄守道, 等. 基于相位差的小电阻接地有源配电网接地故障保护算法[J]. 电工技术学报, 2024, 39(23): 7418-7429.
Li Jun, He Min, Huang Shoudao, et al.Grounding fault protection algorithm of small resistance earthing active distribution network based on phase difference[J]. Transactions of China Electrotechnical Society, 2024, 39(23): 7418-7429.
[4] 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.
[5] 徐萌, 邹贵彬, 高磊, 等. 含逆变型分布式电源的配电网正序阻抗纵联保护[J]. 电力系统自动化, 2017, 41(12): 93-99.
Xu Meng, Zou Guibin, Gao Lei, et al.Pilot protection of positive sequence impedance for distribution network with inverter-based distributed generator[J]. Automation of Electric Power Systems, 2017, 41(12): 93-99.
[6] Chen Guobin, Liu Yiqing, Yang Qifan.Impedance differential protection for active distribution network[J]. IEEE Transactions on Power Delivery, 2020, 35(1): 25-36.
[7] 晁晨栩, 郑晓冬, 高飘, 等. 含高比例光伏配电网的高频阻抗差动保护[J]. 中国电机工程学报, 2021, 41(20): 6968-6979.
Chao Chenxu, Zheng Xiaodong, Gao Piao, et al.High frequency impedance differential protection with high proportion of photovoltaic power distribution network[J]. Proceedings of the CSEE, 2021, 41(20): 6968-6979.
[8] 徐萌, 邹贵彬, 陈宁, 等. 基于故障超前相的有源配电网能量方向纵联保护方法[J]. 电力自动化设备, 2017, 37(1): 58-64.
Xu Meng, Zou Guibin, Chen Ning, et al.Energy-directional pilot protection based on leading-phase for active distribution network[J]. Electric Power Automation Equipment, 2017, 37(1): 58-64.
[9] Zhou Chenghan, Zou Guibin, Zhang Shuo, et al.Energy-based directional pilot protection for distribution networks with IBDGs considering unmeasured load switching[J]. CSEE Journal of Power and Energy Systems, 2024, 10(1): 139-150.
[10] 和敬涵, 王语然, 李猛, 等. 基于电流波形畸变特征的高比例光伏配电网故障方向判别原理[J]. 电网技术, 2023, 47(12): 4856-4867.
He Jinghan, Wang Yuran, Li Meng, et al.New fault direction identification based on current distortion characteristics in high proportion PV distribution system[J]. Power System Technology, 2023, 47(12): 4856-4867.
[11] 戴志辉, 吴桐, 何静远, 等. 基于控保协同的有源配网主动注入式保护方法[J]. 电力系统保护与控制, 2024, 52(3): 94-103.
Dai Zhihui, Wu Tong, He Jingyuan, et al.An active distribution network active injection protection method based on control-protection coordination[J]. Power System Protection and Control, 2024, 52(3): 94-103.
[12] Gao Houlei, Li Juan, Xu Bingyin.Principle and implementation of current differential protection in distribution networks with high penetration of DGs[J]. IEEE Transactions on Power Delivery, 2017, 32(1): 565-574.
[13] 周成瀚, 邹贵彬, 杜肖功, 等. 基于正序电流故障分量的有源配电网纵联保护[J]. 中国电机工程学报, 2020, 40(7): 2102-2112, 2390.
Zhou Chenghan, Zou Guibin, Du Xiaogong, et al.A pilot protection method based on positive sequence fault component current for active distribution networks[J]. Proceedings of the CSEE, 2020, 40(7): 2102-2112, 2390.
[14] Zang Lindong, Zou Guibin, Zhou Chenghan, et al.A d-axis based current differential protection scheme for an active distribution network[J]. Protection and Control of Modern Power Systems, 2022, 7(1): 23.
[15] Joshua A M, Vittal K P.Superimposed current based differential protection scheme for AC microgrid feeders[J]. Applied Energy, 2023, 341: 121079.
[16] Li Botong, Chen Fahui, Li Bin, et al.A multi-terminal current differential protection setting method for fully weak-infeed distribution networks based on restricted enumeration method[J]. IEEE Transactions on Smart Grid, 2024, 15(3): 2570-2585.
[17] 袁通, 高厚磊, 彭放, 等. 免疫同步误差的有源配电网多端纵联保护方法[J]. 电网技术, 2023, 47(12): 4847-4861.
Yuan Tong, Gao Houlei, Peng Fang, et al.Multiterminal pilot protection for active distribution networks immune to synchronization error[J]. Power System Technology, 2023, 47(12): 4847-4861.
[18] 王子璇, 马啸, 杨勇, 等. 计及不可测分支负荷电源助增效应的有源配网幅值差动保护新判据[J]. 中国电机工程学报, 2020, 40(增刊1): 56-68.
Wang Zixuan, Ma Xiao, Yang Yong, et al.A new criterion for amplitude differential protection of active distribution network considering the boosting effect of unmeasurable branch load power supply[J]. Proceedings of the CSEE, 2020, 40(S1): 56-68.
[19] 肖澍昱, 林湘宁, 魏繁荣, 等. 面向含不可测分支配电线路不对称故障可靠辨识的负序电流比相保护判据[J]. 电工技术学报, 2023, 38(9): 2435-2447.
Xiao Shuyu, Lin Xiangning, Wei Fanrong, et al.Phase comparison protection of negative sequence current for distribution lines with unmeasurable branches[J]. Transactions of China Electrotechnical Society, 2023, 38(9): 2435-2447.
[20] 罗国敏, 谭颖婕, 吴梦宇, 等. 考虑电压跌落差异的有源配电网功率差动保护[J]. 电工技术学报, 2025, 40(4): 1287-1306.
Luo Guomin, Tan Yingjie, Wu Mengyu, et al.Power differential protection for active distribution networks considering voltage drop differences[J]. Transactions of China Electrotechnical Society, 2025, 40(4): 1287-1306.
[21] 梁伟宸, 王泽众, 周成瀚, 等. 考虑不可测T接负荷的配电网虚拟三端电流差动保护[J]. 电力系统保护与控制, 2024, 52(15): 81-90.
Liang Weichen, Wang Zezhong, Zhou Chenghan, et al.Virtual three-terminal current differential protection for distribution networks considering unmeasurable T-connected loads[J]. Power System Protection and Control, 2024, 52(15): 81-90.
[22] 戴志辉, 何静远, 王文卓, 等. 适用于逆变型分布式电源T接的配电网线路纵联保护方案[J]. 电力自动化设备, 2024, 44(5): 88-94, 119.
Dai Zhihui, He Jingyuan, Wang Wenzhuo, et al.Line pilot protection scheme for distribution network with inverter-interfaced distributed generation in T-connection mode[J]. Electric Power Automation Equipment, 2024, 44(5): 88-94, 119.
[23] 国家市场监督管理总局, 国家标准化管理委员会. 光伏发电系统接入配电网技术规定: GB/T 29319—2024[S]. 北京: 中国标准出版社, 2024.
[24] 郑涛, 邹芃蓥, 王子鸣. 计及锁相环动态响应特性的光伏并网系统故障电流解析计算[J]. 电网技术, 2022, 46(12): 4656-4667.
Zheng Tao, Zou Pengying, Wang Ziming.Fault current analysis of photovoltaic grid-connected system considering dynamic response characteristics of PLL[J]. Power System Technology, 2022, 46(12): 4656-4667.
[25] Dubey K, Jena P.A novel high-impedance fault detection technique in smart active distribution systems[J]. IEEE Transactions on Industrial Electronics, 2024, 71(5): 4861-4872.
[26] 麻秀范, 张乐萱, 于琨澎, 等. 考虑5G基站备用储能优化调控的配电网重构双层优化方法[J]. 电工技术学报, 2024, 39(16): 5028-5041.
Ma Xiufan, Zhang Lexuan, Yu Kunpeng, et al.A two-layer optimization approach for distribution network reconfiguration considering optimal regulation of 5G base station backup energy storage[J]. Transactions of China Electrotechnical Society, 2024, 39(16): 5028-5041.