Analysis and Suppression of Voltage Transformer Fusing Mechanism in 20 kV Distribution Network
Yang Ming1, Shi Yifeng1, Sima Wenxia1, Liu Yao2, Xia Zipeng2
1. State Key Laboratory of Power Transmission Equipment Technology Chongqing University Chongqing 400044 China; 2. Zhuhai Power Supply Bureau of Guangdong Power Grid Co. Ltd Zhuhai 519000 China
Abstract：To cope with the rapid growth of urban power load and density, 20 kV distribution networks have been put into use in Suzhou, Shenzhen and other places, becoming the development trend of medium voltage distribution networks in major cities in China. The frequent occurrence of voltage transformer (VT) fuse blowing accidents in 20 kV distribution networks affects the safe and stable operation of the system. Due to power supply requirements, the length of cables in 20 kV distribution networks is extremely long, and the capacitance to ground is large. The ratio of capacitive impedance to inductive impedance in the system is much smaller than the range specified in the Peterson resonance criterion, resulting in a fundamental change in the electromagnetic energy interaction mechanism of the system. Ferroresonance will no longer occur, which is significantly different from the fault transient in traditional 10 kV distribution networks. However, existing research has overlooked the nonlinear excitation characteristics of VT, and has not yet conducted in-depth analysis of the electromagnetic energy interaction mechanism and influencing factors in this process, making it difficult to support research on suppression measures and leading to difficulties in preventing VT fuse blowing accidents. Therefore, this article aims to reveal the mechanism of fuse blowing accidents on VT primary side in large-scale distribution networks and propose targeted suppression measure. Based on a actual 20 kV distribution network, the fault energy interaction circuit is extracted, and the process of cable to ground capacitance discharge after a short circuit is analyzed. Establish a nonlinear differential equation for the process of cable capacitance discharging to VT, characterize the nonlinear excitation characteristics of VT based on the principle of piecewise linearization, obtain segmented time-domain analytical solutions of VT primary side current for the equation under different states, and compare the error between analytical calculations and simulation results to achieve accurate analysis of the process. Based on the analytical formula of VT primary side current, calculate its angular frequency and time constant, and then analyze the law of VT current characteristics changing from "quantitative" to "qualitative" during the process of increasing the ground capacitance in system, revealing the mechanism of electromagnetic energy interaction throughout the entire process of system fault. Construct a 20 kV system electromagnetic transient simulation model, reproduce the fault waveform of the fuse accident, analyze the waveform characteristics through analytical calculations, reveal the influence of system operation mode on current, and study the risk of VT fuse blowing. Based on mechanism analysis, targeted suppression measures are proposed to suppress the amplitude of VT primary side overcurrent through discharge circuit topology reconstruction. Build a high-voltage test platform in the laboratory, conduct suppression measures verification experiment, further prove the effectiveness and feasibility of the suppression measure proposed in this paper. Research has shown that the analytical calculation results in this article are accurate and can analyze the VT high-voltage side fuse mechanism in large-scale distribution networks. The proposed suppression measures have significant effects and high feasibility, and the research results can support the safe and stable operation of 20 kV distribution networks.
杨鸣, 史一丰, 司马文霞, 刘尧, 夏子鹏. 20 kV配电网互感器熔断机制分析及抑制措施[J]. 电工技术学报, 2024, 39(23): 7577-7591.
Yang Ming, Shi Yifeng, Sima Wenxia, Liu Yao, Xia Zipeng. Analysis and Suppression of Voltage Transformer Fusing Mechanism in 20 kV Distribution Network. Transactions of China Electrotechnical Society, 2024, 39(23): 7577-7591.
[1] 魏庆海, 吕鸣镝, 周莉梅, 等. 配电网采用20kV供电的前景分析[J]. 电网技术, 2008, 32(23): 61-66. Wei Qinghai, Lü Mingdi, Zhou Limei, et al.Prospective analysis of adopting 20 kV voltage in distribution system[J]. Power System Technology, 2008, 32(23): 61-66. [2] 何健宇. 广州配电网20kV升压改造关键技术研究[D]. 广州: 华南理工大学, 2017. He Jianyu.Technology discussion of Guangzhou distribution network transformation boost to 20kV[D]. Guangzhou: South China University of Technology, 2017. [3] 肖瑞超. 20kV配电网接地故障分析及保护原理研究[D]. 广州: 华南理工大学, 2021. Xiao Ruichao.Research on ground fault analysis and protection principle of 20kV distribution network[D]. Guangzhou: South China University of Technology, 2021. [4] 路志建, 常江, 白晓斌, 等. 电力电缆铝芯线与铜连接管的电磁焊接条件研究[J]. 电工技术学报, 2023, 38(20): 5620-5633. Lu Zhijian, Chang Jiang, Bai Xiaobin, et al.Research on electromagnetic pulse welding conditions of aluminum core wire and copper connecting tube of power cable[J]. Transactions of China Electrotechnical Society, 2023, 38(20): 5620-5633. [5] 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 for flexible DC distribution system based on cable incipient fault section location[J]. Automation of Electric Power Systems, 2023, 47(4): 163-171. [6] 陈锐, 曾杰, 郑雅玲, 等. 20kV配电网电压互感器一次侧电流的仿真与分析[J]. 广东电力, 2022, 35(2): 54-65. Chen Rui, Zeng Jie, Zheng Yaling, et al.Simulation and analysis of primary side current of PT in 20 kV distribution network[J]. Guangdong Electric Power, 2022, 35(2): 54-65. [7] 梁兆文. 配网PT熔断器频繁熔断原因及解决措施研究[D]. 广州: 华南理工大学, 2016. Liang Zhaowen.Research on causes and solutions of the frequent fusing problem of PT fuse in distribution network[D]. Guangzhou: South China University of Technology, 2016. [8] 王宾, 张超, 丁心志. 中性点直接接地系统单相串联铁磁谐振时域解析分析[J]. 中国电机工程学报, 2022, 42(6): 2124-2132. Wang Bin, Zhang Chao, Ding Xinzhi.Time domain analytical analysis of single-phase series ferromagnetic resonance in neutral point solid grounding power system[J]. Proceedings of the CSEE, 2022, 42(6): 2124-2132. [9] 张超, 王宾, 张海, 等. 中性点直接接地电网单相串联铁磁谐振检测与类型辨识[J]. 电力系统自动化, 2022, 46(19): 172-179. Zhang Chao, Wang Bin, Zhang Hai, et al.Detection and type identification of single-phase series ferroresonance in neutral point solid grounding power grid[J]. Automation of Electric Power Systems, 2022, 46(19): 172-179. [10] 周小梅, 杨以涵, 谭伟璞. 配电系统PT高压熔断器熔断的原因分析[J]. 现代电力, 2007, 24(4): 34-37. Zhou Xiaomei, Yang Yihan, Tan Weipu.Cause analysis of PT high-voltage fuse blow in power distribution system[J]. Modern Electric Power, 2007, 24(4): 34-37. [11] 王明钦, 陈维江, 李永君, 等. 油田35kV系统电压互感器高压熔断器异常熔断故障的抑制措施[J]. 电网技术, 2012, 36(12): 283-288. Wang Mingqin, Chen Weijiang, Li Yongjun, et al.A countermeasure to deal with abnormal fusing of high voltage fuse for potential transformer in 35 kV oilfield power distribution system[J]. Power System Technology, 2012, 36(12): 283-288. [12] 郝攀. 配网铁磁谐振过电压及其抑制措施[D]. 南京: 东南大学, 2018. Hao Pan.The ferroresonance overvoltage and suppression measures in distribution network[D]. Nanjing: Southeast University, 2018. [13] 林莉, 王军兵, 唐凤英, 等. 10kV电压互感器损坏的仿真计算研究[J]. 电力系统保护与控制, 2012, 40(17): 51-55. Lin Li, Wang Junbing, Tang Fengying, et al.Simulation and computational analysis on potential transformer damage in 10kV system[J]. Power System Protection and Control, 2012, 40(17): 51-55. [14] 王军兵. 10kV电网单相接地引起电压互感器损坏的机理研究[D]. 重庆: 重庆大学, 2012. Wang Junbing.10kV potential transformer damage mechanism research caused by single phase grounding[D]. Chongqing: Chongqing University, 2012. [15] Zhao Xiaofeng, Qiu Yingdan, Li Qian, et al.Simulation analysis and suppression method of PT low frequency oscillation in distribution network[C]//2018 International Conference on Power System Technology (POWERCON), Guangzhou, China, 2018: 3151-3157. [16] Abdelazim T, Dionise T J, Yanniello R.A case study of voltage transformer failures in a modern data center: analysis, mitigation, and solution implementation[C]//2016 IEEE/IAS 52nd Industrial and Commercial Power Systems Technical Conference (I&CPS), Detroit, MI, USA, 2016: 1-11. [17] McDermit D C, Shipp D D, Dionise T J, et al. Medium-voltage switching transient-induced potential transformer failures: prediction, measurement, and practical solutions[J]. IEEE Transactions on Industry Applications, 2013, 49(4): 1726-1737. [18] 郑雅玲, 韩永霞, 余菲, 等. 基于配电网全架构精确电磁暂态模型的VT一次侧过流机理及影响因素分析[J]. 广东电力, 2023, 36(1): 48-58. Zheng Yaling, Han Yongxia, Yu Fei, et al.Analysis of VT primary side overcurrent mechanism and influencing factors based on accurate electromagnetic transient model of distribution network structure[J]. Guangdong Electric Power, 2023, 36(1): 48-58. [19] Evdokunin G A, Brilinskii A S, Chudny V S, et al.Mathematical modeling and analysis of antiresonant properties of a 35 kV voltage measuring transformer[C]//2022 Conference of Russian Young Researchers in Electrical and Electronic Engineering (ElConRus), Saint Petersburg, Russian Federation, 2022: 1170-1173. [20] 林莉, 何月, 王军兵, 等. 中性点不接地电网单相接地时电压互感器损坏机理[J]. 高电压技术, 2013, 39(5): 1114-1120. Lin Li, He Yue, Wang Junbing, et al.Mechanism of potential transformer damaged in ungrounded neutral power system[J]. High Voltage Engineering, 2013, 39(5): 1114-1120. [21] Van Wagner.Experimental evaluation of switching induced transformer resonance mitigation[J]. IEEE Transactions on Industry Applications, 2018, 54(4): 3165-3169. [22] Pordanjani I R, Liang Xiaodong, Wang Yunfei, et al.Single-phase ferroresonance in an ungrounded system during system energization[J]. IEEE Transactions on Industry Applications, 2021, 57(4): 3530-3537. [23] Sloot J G J, Meng X Z, Vermij L. Fuse characteristics determined by melting or ageing?[J]. European Transactions on Electrical Power, 1998, 8(3): 213-215. [24] Bahman A S, Iannuzzo F, Holmgaard T, et al.Reliability-oriented environmental thermal stress analysis of fuses in power electronics[J]. Microelectronics Reliability, 2017, 76: 25-30. [25] Bajda Y, Grechko O, Buhaichuk V, et al.To the problem of protection of medium voltage instrument transformers with fuses: analytical research[J]. Lighting Engineering & Power Engineering, 2021, 60(3): 92-102. [26] 陈绍英, 葛栋, 常挥, 等. 配电网超低频振荡的仿真计算研究[J]. 高电压技术, 2004, 30(5): 18-19, 22. Chen Shaoying, Ge Dong, Chang Hui, et al.Study and simulation calculation of very low frequencies oscillations in power distribution system[J]. High Voltage Engineering, 2004, 30(5): 18-19, 22. [27] 吉兴全, 朱仰贺, 韩国正, 等. 中压配电网低频振荡仿真分析及消谐措施[J]. 电网技术, 2016, 40(8): 2451-2455. Ji Xingquan, Zhu Yanghe, Han Guozheng, et al.Simulation analysis of low frequency oscillation and study on resonance elimination measures in MV distribution network[J]. Power System Technology, 2016, 40(8): 2451-2455. [28] 杨鸣, 熊钊, 司马文霞, 等. 电磁式电压互感器“低频过电压激励-响应”逆问题求解[J]. 电工技术学报, 2021, 36(17): 3605-3613. Yang Ming, Xiong Zhao, Sima Wenxia, et al.Solution of the inverse problem of “low-frequency overvoltage excitation to response” for electromagnetic potential transformers[J]. Transactions of China Electrotechnical Society, 2021, 36(17): 3605-3613. [29] 沈泽亮, 汪金刚, 王谦, 等. 一种基于低频窄带扫描的电磁式电压互感器杂散电容测量与精确建模方法[J]. 电工技术学报, 2023, 38(8): 2211-2221. Shen Zeliang, Wang Jingang, Wang Qian, et al.A method for stray capacitance measuring and refined modeling of potential transformer based on low frequency and narrow band scanning[J]. Transactions of China Electrotechnical Society, 2023, 38(8): 2211-2221. [30] 杨北超, 范学鑫, 王瑞田, 等. 考虑铁心非线性的三相立体卷铁心变压器建模及空载特性分析[J]. 电工技术学报, 2022, 37(9): 2263-2274. Yang Beichao, Fan Xuexin, Wang Ruitian, et al.Modeling and No-load characteristics analysis of 3D wound core transformer considering core nonlinearity[J]. Transactions of China Electrotechnical Society, 2022, 37(9): 2263-2274. [31] Dommel H W. Electromagnetic Transients Program. Reference Manual (EMTP Theory Book)[M]. Portland: Bonneville Power Administration, 1986. [32] 国家质量监督检验检疫总局, 中国国家标准化管理委员会. 互感器试验导则第2部分:电磁式电压互感器: GB/T 22071.2—2017[S]. 北京: 中国标准出版社, 2018. [33] IEEE Power and Energy Society. IEEE standard for general requirements and test code for dry-type and oil-immersed smoothing reactors and for dry-type converter reactors for dc power transmission: IEEE Std 1277—2020[S]. IEEE, 2020. [34] 贲彤, 方敏, 陈龙, 等. 非晶合金铁心电抗器减振结构的电磁-机械耦合拓扑优化[J]. 电工技术学报, 2023, 38(24): 6553-6564. Ben Tong, Fang Min, Chen Long, et al.Optimization of magnetic-mechanical coupling topology for vibration damping structures of amorphous alloy core reactor[J]. Transactions of China Electrotechnical Society, 2023, 38(24): 6553-6564. [35] 代岭均, 邹亮, 孙玉鑫, 等. 干式空心电抗器五环简化缩比模型最优结构对比分析[J]. 电工技术学报, 2023, 38(4): 1088-1103. Dai Lingjun, Zou Liang, Sun Yuxin, et al.Investigation of comparison on optimal structure of five-loop simplified scaling model for dry-type air-core reactors[J]. Transactions of China Electrotechnical Society, 2023, 38(4): 1088-1103.
2024, Vol. 39 
