Time Delay Control Method for Distributed Sheath Current Sensing System of Underground Cross-Bonding High Voltage Cable
Zhou Shasha1, Wang Hang1, Yang Bin2, Xia Zhanran2, Zhou Chengke3
1. Hubei Engineering Research Center for Safety Monitoring of New Energy and Power Grid Equipment Hubei University of Technology Wuhan 430068 China; 2. Wuhan Power Supply Company Hubei Power Supply Company State Grid Wuhan 430024 China; 3. Glasgow Caledonian University Glasgow UK G4 0BA
Abstract:Underground HV (High Voltage) cable is the backbone of modern urban power systems. In the last decades, the sheath-to-ground fault is becoming one of the main modes contributing to the single-phase grounding fault. Sheath current sensing is widely adopted in field tests to detect the sheath-to-ground fault. However, the synchronization of distributed sheath current sensing based on GPS (Global Position System) or Beidou is unstable because the time transfer tag is usually unavailable in underground cable tunnels. Therefore, a time delay control method based on the Smith predictor compensator and recursive least squares method (RLSM) is proposed using the capacitive current as a reference of the measured sheath current in the same sheath loop. Firstly, the architecture of the distributed sheath current sensing in HV cross-boned cable systems is introduced, and the formulation of the measured sheath current in the same sheath loop with time delay is deduced. Secondly, the electromagnetic coupling relationship between the sheath current and load current is modeled, and the phasor difference of the measured sheath current in the same sheath loop without time delay is formulated as the reference of the RLSM. Thirdly, the parallel Smith predictor is proposed to compensate for the time delay error of the adjacent sheath current detection points in the same sheath loop. Finally, a recursive least square tracking method for the time delay error of the multi-sheath current sensor is proposed to obtain the time delay with the minimum residual. The proposed method is verified by field tests of a 220 kV cross-boned cable supplying the high-speed traction transformer. The results show that the waveform of capacitive current, which is the reference of RLSM, inosculates well with the difference of the measured sheath current in the same sheath loop after using the proposed method. The maximum difference is 0.297 A, and the minimum difference is 0.002 A. Moreover, the reference standard for time delay estimation is the average residual of the three loops, and the minimum residual of each loop is between 0.28~0.33 A. In addition, the Smith predictor is translated for the 197th time, and the residual value in the overall range is the smallest when the time delay offset is 3.94 s, which is 0.3 A. The following conclusions can be drawn from the experiment: (1) The instantaneous current difference between adjacent sheaths in the same loop inosculates with the instantaneous capacitor current after using the proposed method, which implies the synchronization of distributed sheath current sensing. (2) When distributed sheath current sensing is asynchronous, the current phasor difference of the sheath is not accurate, which will affect the evaluation of the grounding state of the sheath. (3) The proposed method converges to the minimum average residual value of 0.3 A in the global range, and the time delay is 3.94 s.
周莎莎, 王航, 杨斌, 夏湛然, 周承科. 地下交叉互联高压电缆分布式护层电流传感系统的时滞控制方法[J]. 电工技术学报, 2024, 39(4): 1234-1244.
Zhou Shasha, Wang Hang, Yang Bin, Xia Zhanran, Zhou Chengke. Time Delay Control Method for Distributed Sheath Current Sensing System of Underground Cross-Bonding High Voltage Cable. Transactions of China Electrotechnical Society, 2024, 39(4): 1234-1244.
[1] Zhou Chengke, Yi Huajie, Dong Xiang.Review of recent research towards power cable life cycle management[J]. High Voltage, 2017, 2(3): 179-187. [2] 陈杰, 吴世林, 胡丽斌, 等. 退役高压电缆附件绝缘状态及理化性能分析[J]. 电工技术学报, 2021, 36(12): 2650-2658. Chen Jie, Wu Shilin, Hu Libin, et al.Analysis of insulation state and physicochemical property of retired high-voltage cable accessories[J]. Transactions of China Electrotechnical Society, 2021, 36(12): 2650-2658. [3] Tang Zeyang, Zhou Chengke, Jiang Wei, et al.Analysis of significant factors on cable failure using the COX proportional hazard model[J]. IEEE Transa- ctions on Power Delivery, 2014, 29(2): 951-957. [4] 唐进, 张姝, 林圣, 等. 计及金属护层结构的电缆单端故障测距方法[J]. 中国电机工程学报, 2016, 36(6): 1748-1756, 1798. Tang Jin, Zhang Shu, Lin Sheng, et al.Single- terminal fault locating method of cables considering the metal sheath structure[J]. Proceedings of the CSEE, 2016, 36(6): 1748-1756, 1798. [5] 严有祥, 朱婷, 张那明, 等. 交直流电缆共沟敷设电磁环境影响因素[J]. 电工技术学报, 2022, 37(6): 1329-1337. Yan Youxiang, Zhu Ting, Zhang Naming, et al.The influence factors of electromagnetic environment in the tunnels with DC cables and AC cables[J]. Transactions of China Electrotechnical Society, 2022, 37(6): 1329-1337. [6] Li Shengtao, Li Jianying.Condition monitoring and diagnosis of power equipment: review and pro- spective[J]. High Voltage, 2017, 2(2): 82-91. [7] 单秉亮, 李舒宁, 杨霄, 等. XLPE配电电缆缺陷诊断与定位技术面临的关键问题[J]. 电工技术学报, 2021, 36(22): 4809-4819. Shan Bingliang, Li Shuning, Yang Xiao, et al.Key problems faced by defect diagnosis and location technologies for XLPE distribution cables[J]. Transa- ctions of China Electrotechnical Society, 2021, 36(22): 4809-4819. [8] 贾科, 施志明, 张旸, 等. 基于电缆早期故障区段定位的柔性直流配电系统保护方法[J]. 电力系统自动化, 2023, 47(4): 163-171. Jia Ke, Shi Zhiming, Zhang Yang, et al.Protection method of flexible DC distribution system based on cable incipient fault section location[J]. Automation of Electric Power Systems, 2023, 47(4): 163-171. [9] 王昊月, 李成榕, 王伟, 等. 高压频域介电谱诊断XLPE电缆局部绝缘老化缺陷的研究[J]. 电工技术学报, 2022, 37(6): 1542-1553. Wang Haoyue, Li Chengrong, Wang Wei, et al.Local aging diagnosis of XLPE cables using high voltage frequency domain dielectric spectroscopy[J]. Transa- ctions of China Electrotechnical Society, 2022, 37(6): 1542-1553. [10] Marzinotto M, Mazzanti G.The feasibility of cable sheath fault detection by monitoring sheath-to-ground currents at the ends of cross-bonding sections[J]. IEEE Transactions on Industry Applications, 2015, 51(6): 5376-5384. [11] Dong Xiang, Yang Yang, Zhou Chengke, et al.Online monitoring and diagnosis of HV cable faults by sheath system currents[J]. IEEE Transactions on Power Delivery, 2017, 32(5): 2281-2290. [12] Shokry M A, Khamlichi A, Garnacho F, et al.Detection and localization of defects in cable sheath of cross bonding configuration by sheath currents[J]. IEEE Transactions on Power Delivery, 2019, 34(4): 1401-1411. [13] Li Zhonglei, Du Boxue, Li Wang.Evaluation of high-voltage AC cable grounding systems based on the real-time monitoring and theoretical calculation of grounding currents[J]. High Voltage, 2018, 3(1): 38-43. [14] Wang Yilin, Ye Hao, Zhang Tongshuai, et al.A data mining method based on unsupervised learning and spatiotemporal analysis for sheath current monito- ring[J]. Neurocomputing, 2019, 352(4): 54-63. [15] 刘福源, 王航, 夏湛然, 等. 交叉互联高压电缆护层保护器故障对同回路两端护层电流相量差的影响[J]. 高电压技术, 2023, 49(3): 1244-1253. Liu Fuyuan, Wang Hang, Xia Zhanran, et al.Influence of the sheath voltage limiter fault on the sheath current phasor difference between the two ends in the same sheath loop in cross-bonded HV cables[J]. High Voltage Engineering, 2023, 49(3): 1244-1253. [16] Yang Yang, Hepburn D M, Zhou Chengke, et al.On-line monitoring of relative dielectric losses in cross-bonded cables using sheath currents[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2017, 24(5): 2677-2685. [17] Li Mingzhen, Zhou Chengke, Zhou Wenjun, et al.A novel fault location method for a cross-bonded HV cable system based on sheath current monitoring[J]. Sensors, 2018, 18(10): 3356-3375. [18] Li Mingzhen, Liu Jianming, Zhu Tao, et al.A novel traveling-wave-based method improved by unsuper- vised learning for fault location of power cables via sheath current monitoring[J]. Sensors, 2019, 19(9): 2083-2107. [19] 徐星, 陈向荣, 杜振东, 等. 基于非解耦节点导纳矩阵的随桥电缆接地方式研究[J]. 电工技术学报, 2021, 36(17): 3664-3674. Xu Xing, Chen Xiangrong, Du Zhendong, et al.Study on bridge-cable grounding system based on the non-decoupling nodal admittance matrix[J]. Transa- ctions of China Electrotechnical Society, 2021, 36(17): 3664-3674. [20] 李根, 王航, 刘海康, 等. 基于逻辑回归的高压电缆交叉互联接地系统缺陷分类识别方法[J]. 高电压技术, 2021, 47(10): 3674-3683. Li Gen, Wang Hang, Liu Haikang, et al.Classification and identification method of grounding system defects in cross-bonded HV cables based on logistic regression[J]. High Voltage Engineering, 2021, 47(10): 3674-3683. [21] Shaban M, Salam M A, Ang S P, et al.Induced sheath voltage in power cables: a review[J]. Renewable and Sustainable Energy Reviews, 2016, 62(1): 1236-1251. [22] 马燕峰, 霍亚欣, 李鑫, 等. 考虑时滞影响的双馈风电场广域附加阻尼控制器设计[J]. 电工技术学报, 2020, 35(1): 158-166. Ma Yanfeng, Huo Yaxin, Li Xin, et al.Design of wide area additional damping controller for doubly fed wind farms considering time delays[J]. Transactions of China Electrotechnical Society, 2020, 35(1): 158-166. [23] 薛安成, 张兆阳, 毕天姝. 基于自适应抗差最小二乘的线路正序参数在线辨识方法[J]. 电工技术学报, 2015, 30(8): 202-209. Xue Ancheng, Zhang Zhaoyang, Bi Tianshu.Online identification of transmission line positive-sequence parameters based on adaptive robust least squares[J]. Transactions of China Electrotechnical Society, 2015, 30(8): 202-209. [24] 谢文超, 赵延明, 方紫微, 等. 带可变遗忘因子递推最小二乘法的超级电容模组等效模型参数辨识方法[J]. 电工技术学报, 2021, 36(5): 996-1005. Xie Wenchao, Zhao Yanming, Fang Ziwei, et al.Variable forgetting factor recursive least squales based parameter identification method for the equivalent circuit model of the supercapacitor cell module[J]. Transactions of China Electrotechnical Society, 2021, 36(5): 996-1005. [25] 程鹏, 刘文泉, 陈冲, 等. 面向电气化铁路牵引供电的光伏发电分相电流控制策略[J]. 电力系统自动化, 2022, 46(19): 145-153. Cheng Peng, Liu Wenquan, Chen Chong, et al.Individual phase current control strategy of photo- voltaic power generation for traction power supply of electrified railway[J]. Automation of Electric Power Systems, 2022, 46(19): 145-153.