Simulation Research on Reactive Power Loss Characteristic of 500 kV Transformer under Late-Time High-Altitude Electromagnetic Pulses
Yang Yifan1, Liu Minzhou1, Xie Yanzhao1, Chen Yuhao1, Tian Shuang2
1. State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong University Xi'an 710049 China; 2. Xi'an Thermal Power Research Institute Co. Ltd Xi'an 710054 China
Abstract：The effect of late-time high-altitude electromagnetic pulses (HEMP E3) can generate geomagnetic induced currents in the circuit between the earth and neutral points of transformers. In serious cases, it may make the transformer core half-cycle saturated, resulting in serious consequences, like distortion of excitation current, increase of reactive power loss, hot-spot heating and vibration. However, the existing literature usually adopted the results under steady-state direct current for E3 impact assessment, and the dynamic characteristics of transformer under E3 waveform were not fully considered. In order to analyze the influence of E3 characteristics, such as high magnitude and short duration, this paper builds an electromagnetic transient model of a 500 kV transformer. Based on IEC 61000-2-9 standard, this paper quantitatively analyzes the resulting variation of excitation current and reactive power loss of the Wye-Delta-connection transformer under HEMP E3, considering the amplitude, rising time, falling time of the induced geoelectric field, as well as transformer load type and other factors. The actual HEMP E3 induced electric fields are affected by the non-uniform earth conductivity and coast effect, and the waveform may change considerably. Thus, this paper calculates the E3 induced electric field under the uniform earth model and the 1D layered conductivity model. The results show that for the realistic earth conductivity models, the induced geoelectric fields change not only in amplitude but also in waveform. Therefore, this paper studies the influence of peak value, rise time and fall time of E3 induced electric field on reactive power loss of 500 kV transformer. To analyze the influence of the electric field amplitude, this paper selects 0.5 times, 1 time, 2 times, 5 times and 10 times of the IEC standard waveform, which are imposed on the 100 km transmission line respectively. The results show that as the amplitude of E3 electric field increases, the reactive power loss will be larger. It is worth noticing that there exists an upper limit of reactive power loss under HEMP E3, which depends on the air core inductance when the transformer is deeply saturated. For the rise time and fall time, this paper focuses on the first wave peak of HEMP E3. The results shows that when the fall time of induced electric field decreases by 80.8%, the fall time of reactive power loss decreases by 80.3% and the amplitude decreases by 20.3%; whereas when the rise time of induced electric field decreases by 83.1%, the rise time of reactive power loss decreases by 44.3%, and the amplitude increases by 7.3%. Therefore, the falling time of HEMP E3 has far more influence on the reactive power loss of the transformer than the rising time. In order to analyze the influence of load types on the transformer under HEMP E3, three types with the same impedance value, namely, resistance, inductance and capacitance are applied to the low-voltage side. The results show that when HEMP E3 electric field is applied, the excitation current and reactive power loss of the transformer are distorted to different levels with different load types. Because of the different phase angle of load impedance, the amplitude of reactive power loss is the largest with capacitive load and the smallest with inductive load. Besides reactive power loss characteristics studied above, HEMP E3 may lead transformer to harmonic distortion, hot-spot heating and vibration, which will be further investigated in future work.
杨一帆, 刘民周, 谢彦召, 陈宇浩, 田爽. 高空电磁脉冲晚期成分作用下500 kV变压器无功损耗仿真研究[J]. 电工技术学报, 2024, 39(1): 267-277.
Yang Yifan, Liu Minzhou, Xie Yanzhao, Chen Yuhao, Tian Shuang. Simulation Research on Reactive Power Loss Characteristic of 500 kV Transformer under Late-Time High-Altitude Electromagnetic Pulses. Transactions of China Electrotechnical Society, 2024, 39(1): 267-277.
[1] 师泯夏, 吴邦, 靳宇晖, 等. 直流偏磁对变压器影响研究综述[J]. 高压电器, 2018, 54(7): 20-36, 43. Shi Minxia, Wu Bang, Jin Yuhui, et al.Research summary on the impacts of DC magnetic bias on transformer[J]. High Voltage Apparatus, 2018, 54(7): 20-36, 43. [2] 王泽忠, 黄天超. 变压器地磁感应电流-无功功率动态关系分析[J]. 电工技术学报, 2021, 36(9): 1948-1955. Wang Zezhong, Huang Tianchao.Analysis of geomagnetically induction current-reactive power dynamic relationship of transformer[J]. Transactions of China Electrotechnical Society, 2021, 36(9): 1948-1955. [3] 刘连光, 朱溪, 王泽忠, 等. 基于K值法的单相四柱式特高压主体变的GIC-Q损耗计算[J]. 高电压技术, 2017, 43(7): 2340-2348. Liu Lianguang, Zhu Xi, Wang Zezhong, et al.Calculation for reactive power loss of single-phase four limbs UHV main transformer due to geomagnetically induced currents with parameter K[J]. High Voltage Engineering, 2017, 43(7): 2340-2348. [4] 刘教民, 朱溪, 刘洪正, 等. 电力变压器的GIC-Q损耗算法的研究综述[J]. 高电压技术, 2018, 44(7): 2284-2291. Liu Jiaomin, Zhu Xi, Liu Hongzheng, et al.Calculation methods for reactive power loss of transformers due to geomagnetically induced current[J]. High Voltage Engineering, 2018, 44(7): 2284-2291. [5] 朱涛, 王丰华. 地磁感应电流作用下大型变压器的温升特性计算[J]. 电工技术学报, 2022, 37(8): 1915-1925. Zhu Tao, Wang Fenghua.Calculation of temperature rise of large transformer under geomagnetically induced current[J]. Transactions of China Electro-technical Society, 2022, 37(8): 1915-1925. [6] 王丰华, 周翔, 高沛, 等. 基于绕组热分布的改进油浸式变压器绕组热点温度计算模型[J]. 高电压技术, 2015, 41(3): 895-901. Wang Fenghua, Zhou Xiang, Gao Pei, et al.Improved thermal circuit model of hot spot temperature in oil-immersed transformers based on heat distribution of winding[J]. High Voltage Engineering, 2015, 41(3): 895-901. [7] 王泽忠, 李明洋, 宣梦真, 等. 单相四柱式变压器直流偏磁下的温升试验及仿真分析[J]. 电工技术学报, 2021, 36(5): 1006-1013. Wang Zezhong, Li Mingyang, Xuan Mengzhen, et al.Temperature rise test and simulation of single-phase four-column transformer under DC-bias[J]. Trans-actions of China Electrotechnical Society, 2021, 36(5): 1006-1013. [8] Dong Xuzhu, Liu Yilu, Kappenman J G.Comparative analysis of exciting current harmonics and reactive power consumption from GIC saturated transformers[C]// 2001 IEEE Power Engineering Society Winter Meeting, Conference Proceedings (Cat. No.01CH37194), Columbus, OH, USA, 2001: 318-322. [9] 颜广兴. 直流偏磁条件下变压器的谐波分析[D]. 广州: 华南理工大学, 2018. [10] 张晓宇, 郑超, 莫品豪, 等. 直流偏磁对变压器保护的影响及直流偏磁保护改进[J]. 电力系统自动化, 2021, 45(4): 148-154. Zhang Xiaoyu, Zheng Chao, Mo Pinhao, et al.Influence of DC magnetic bias on transformer protection and improvement of DC magnetic bias protection[J]. Automation of Electric Power Systems, 2021, 45(4): 148-154. [11] 张冰, 刘连光, 肖湘宁. 地磁感应电流对变压器振动、噪声的影响[J]. 高电压技术, 2009, 35(4): 900-904. Zhang Bing, Liu Lianguang, Xiao Xiangning.Effects of geomagnetically induced current on the vibration and noise of transformers[J]. High Voltage Engin-eering, 2009, 35(4): 900-904. [12] 李冰, 王泽忠, 刘海波, 等. 直流偏磁下500kV单相变压器振动噪声的试验研究[J]. 电工技术学报, 2021, 36(13): 2801-2811. Li Bing, Wang Zezhong, Liu Haibo, et al.Experiment on vibro-acoustic characteristic of 500kV single-phase transformer under DC-bias[J]. Transactions of China Electrotechnical Society, 2021, 36(13): 2801-2811. [13] 陈宇浩, 谢彦召, 刘民周, 等. 高空电磁脉冲作用下电力系统主要效应模式分析[J]. 强激光与粒子束, 2019, 31(7): 49-54. Chen Yuhao, Xie Yanzhao, Liu Minzhou, et al.Analysis of high-altitude electromagnetic effect models on power system[J]. High Power Laser and Particle Beams, 2019, 31(7): 49-54. [14] Hutchins T R, Overbye T J.Power system dynamic performance during the late-time (E3) high-altitude electromagnetic pulse[C]//2016 Power Systems Computation Conference (PSCC), Genoa, Italy, 2016: 1-6. [15] Gilbert J, Kappenman J, Radasky W, et al.The late-time (E3) high-altitude electromagnetic pulse (HEMP) and its impact on the U.S. power grid[R]. Oak Ridge: Oak Ridge National Laboratory, 2010. [16] 李泓志, 崔翔, 刘东升, 等. 直流偏磁对三相电力变压器的影响[J]. 电工技术学报, 2010, 25(5): 88-96. Li Hongzhi, Cui Xiang, Liu Dongsheng, et al.Influence on three-phase power transformer by DC bias excitation[J]. Transactions of China Electro-technical Society, 2010, 25(5): 88-96. [17] Girgis R S, Vedante K B.Impact of GICs on power transformers: overheating is not the real issue[J]. IEEE Electrification Magazine, 2015, 3(4): 8-12. [18] Buticchi G, Lorenzani E.Detection method of the DC bias in distribution power transformers[J]. IEEE Transactions on Industrial Electronics, 2013, 60(8): 3539-3549. [19] Marti L, Berge J, Varma R K.Determination of geomagnetically induced current flow in a transformer from reactive power absorption[J]. IEEE Transactions on Power Delivery, 2013, 28(3): 1280-1288. [20] 刘连光, 钱晨, 朱溪, 等. 应用K值算法的甘肃电网GIC-Q扰动计算[J]. 电网技术, 2016, 40(8): 2370-2375. Liu Lianguang, Qian Chen, Zhu Xi, et al.Calculation of geomagnetically induced currents reactive power loss disturbance in Gansu grid with parameter K[J]. Power System Technology, 2016, 40(8): 2370-2375. [21] Berge J, Varma R K, Marti L.Laboratory validation of the relationship between geomagnetically induced current (GIC) and transformer absorbed reactive power[C]//2011 IEEE Electrical Power and Energy Conference, Winnipeg, MB, Canada, 2011: 491-495. [22] Overbye T J, Shetye K S, Hutchins T R, et al.Power grid sensitivity analysis of geomagnetically induced currents[J]. IEEE Transactions on Power Systems, 2013, 28(4): 4821-4828. [23] You Y, Fuchs E F, Lin D, et al.Reactive power demand of transformers with DC bias[J]. IEEE Industry Applications Magazine, 1996, 2(4): 45-52. [24] Rezaei-Zare A.Behavior of single-phase transformers under geomagnetically induced current conditions[J]. IEEE Transactions on Power Delivery, 2014, 29(2): 916-925. [25] International Electrotechnical Commission.IEC 61000-2-9 Electromagnetic compatibility (EMC)-part 2: environment - description of HEMP environment-conducted disturbance[S]. International Electrotechnical Commission, 1996. [26] Wait J R.Lectures on wave propagation theory[M]. New York: Pergamon Press, 1981. [27] Chew W C.Waves and fields in inhomogeneous media[M]. New York: IEEE Press, 1995. [28] Pirjola R, Boteler D.Calculation methods of the electric and magnetic fields at the Earth’s surface produced by a line current[J]. Radio Science, 2002, 37(3): 14. [29] 刘青, 韩康康, 徐婷, 等. 新疆2020年规划电网地磁感应电流的分布规律及敏感性分析[J]. 电网技术, 2017, 41(11): 3678-3684. Liu Qing, Han Kangkang, Xu Ting, et al.Analysis of distribution regularities and sensitivity of geomagnetically induced currents in planned Xinjiang 750kV power grid[J]. Power System Technology, 2017, 41(11): 3678-3684. [30] Lee R H W, Shetye K S, Birchfield A B, et al. Using detailed ground modeling to evaluate electric grid impacts of late-time high-altitude electromagnetic pulses (E3 HEMP)[J]. IEEE Transactions on Power Systems, 2018, 34(2): 1549-1557. [31] 高志伟, 周于翔, 朱思熠. 晚期HEMP作用下铁路牵引供电系统GIC算法研究[J]. 强激光与粒子束, 2021, 33(9): 47-53. Gao Zhiwei, Zhou Yuxiang, Zhu Siyi.Study on GIC algorithm of railway traction power supply system under action of late time HEMP[J]. High Power Laser and Particle Beams, 2021, 33(9): 47-53. [32] 王泽忠, 司远, 刘连光. 考虑地下各向异性介质的磁暴感应地电场研究[J]. 电工技术学报, 2022, 37(5): 1070-1077, 1114. Wang Zezhong, Si Yuan, Liu Lianguang.Study on the induced geoelectric field of geomagnetic storm considering the underground anisotropic medium[J]. Transactions of China Electrotechnical Society, 2022, 37(5): 1070-1077, 1114. [33] 郑宽. 大电网地磁感应电流影响因素及建模方法研究[D]. 北京: 华北电力大学, 2014. [34] 王泽忠, 刘恪, 李明洋, 等. 不同性质负载下特高压变压器直流偏磁特性分析[J]. 高压电器, 2021, 57(5): 7-13. Wang Zezhong, Liu Ke, Li Mingyang, et al.Analysis of DC magnetic bias characteristics of UHV transformer under load with different properties[J]. High Voltage Apparatus, 2021, 57(5): 7-13. [35] 王泽忠, 李冰, 李明洋, 等. 不同负载下直流偏磁对特高压变压器各侧绕组电流影响的计算及分析[J]. 强激光与粒子束, 2019, 31(7): 78-85. Wang Zezhong, Li Bing, Li Mingyang, et al.Research on winding current of UHV transformer with different load types under DC bias[J]. High Power Laser and Particle Beams, 2019, 31(7): 78-85.
2024, Vol. 39 
