Abstract：The pulse power supply for electromagnetic launch has significant characteristics such as high power and long pulse width. Therefore, its dielectric energy storage pulse capacitors generally have the indicators of high voltage and large capacity. The discharge current amplitude and pulse width of a single pulse capacitor are generally in the order of 100 kA and several milliseconds, the working voltage is usually 5~10 kV, the repetition frequency is less than 1Hz, and the capacity and energy storage scale can generally reach the order of several millifarad and 100 kJ. Among various dielectric insulation materials used in the manufacturing of capacitor, biaxially oriented polypropylene (BOPP) has become one of the preferred materials for high energy storage density pulse capacitor due to their high breakdown field strength, low loss, good temperature resistance, machinability, and relatively low cost. Continuous temperature rise is an important factor that leads to deterioration or even failure of the energy storage pulse capacitor for electromagnetic launch. The phenomenon of local breakdown caused by defects in polymer films is inevitable. Although pulse capacitor has a certain self-healing ability, the increase in temperature will increase the probability of electric thermal breakdown, leading to accelerated life decay. In addition, an increase in temperature can also lead to an increase in the conductivity of dielectric film, resulting in a decrease in the insulation resistance of capacitor, an increase in the leakage current, and a decrease in the voltage holding capacity. References point out that thermal aging is one of the important reasons for the failure of pulse capacitor. Related studies indicate that for every 8℃ increase in temperature, the lifespan of pulse capacitor decreases by half of its original. Thermal model for pulse capacitor has been established in reference, but the corresponding model has been extensively simplified and only considers axial heat distribution. Anisotropic thermal conductivity and its impact on the insulation safety, self-healing phenomenon and its impact on the operating temperature, deterioration phenomenon and pattern under the repeated frequency discharge conditions, such similar topics are also introduced in the existing references surrounding the pulse capacitor. In summary, the research methods and conclusions of temperature distribution of polymer film pulse capacitor lack the consideration of the equivalence of extreme application conditions and the comprehensiveness, accuracy and real-time of measurement results. In addition, relevant references have mainly studied the heat transfer problem at the single-core level of capacitor and there is no reference that has analyzed the continuous temperature rise of full-size high-voltage high-capacity pulse capacitor. The latter has important practical significance for the safety of electromagnetic launch devices. In this paper, by means of theoretical analysis, finite element simulation and in-situ test, the internal temperature rise of a high-voltage large-capacitance pulse capacitor under continuous surge pulse current is systematically studied. The results show that after 50 times of pulse discharge, the temperature rise caused only by the Joule heat and self-healing heat inside the capacitor is about 0.7~0.9℃, but under the effect of parallel copper bar heat conduction, the temperature rise at the end of capacitor core unit can reach up to 21℃, which shows that the main factor affecting the maximum temperature rise of the inner capacitor core unit and its application safety is the heat conduction outside the capacitor core unit. The research methods and conclusions of this paper have positive significance and reference value for improving the heat dissipation process of pulse capacitor for electromagnetic launch and improving its working reliability under extreme application conditions.
朱博峰, 张晓, 张冠祥, 王鑫, 鲁军勇. 高压大容量介电储能脉冲电容器电热耦合仿真分析与原位测试[J]. 电工技术学报, 2025, 40(1): 217-225.
Zhu Bofeng, Zhang Xiao, Zhang Guanxiang, Wang Xin, Lu Junyong. Finite Element Simulation and In-Situ Testing of Electrothermal Coupling in Dielectric Energy Storage Pulse Capacitor for Electromagnetic Launch. Transactions of China Electrotechnical Society, 2025, 40(1): 217-225.
[1] 马伟明, 鲁军勇. 电磁发射技术的研究现状与挑战[J]. 电工技术学报, 2023, 38(15): 3943-3959. Ma Weiming, Lu Junyong.Research progress and challenges of electromagnetic launch technology[J]. Transactions of China Electrotechnical Society, 2023, 38(15): 3943-3959. [2] 胡鑫凯, 鲁军勇, 李白, 等. 瞬态条件下电磁轨道发射装置绝缘体热损伤分析[J]. 电工技术学报, 2023, 38(21): 5673-5681. Hu Xinkai, Lu Junyong, Li Bai, et al.Thermal damage analysis of insulator in electromagnetic rail launcher under transient conditions[J]. Transactions of China Electrotechnical Society, 2023, 38(21): 5673-5681. [3] 李白, 鲁军勇, 谭赛, 等. 高速滑动电接触电枢表面动态磨损过程研究[J]. 电工技术学报, 2023, 38(1): 131-139. Li Bai, Lu Junyong, Tan Sai, et al.Research on dynamic wear process of armature surface in high-speed sliding electric contact[J]. Transactions of China Electrotechnical Society, 2023, 38(1): 131-139. [4] 翟小飞, 李鑫航, 刘华, 等. 电磁轨道发射系统电路模型及发射效率研究[J]. 电工技术学报, 2023, 38(11): 2841-2849, 2860. Zhai Xiaofei, Li Xinhang, Liu Hua, et al.Research on circuit model and launch efficiency of electromagnetic rail launch system[J]. Transactions of China Electrotechnical Society, 2023, 38(11): 2841-2849, 2860. [5] 朱博峰, 鲁军勇, 张晓, 等. 基于高频变压器漏抗理论的脉冲电源多模块并联充电误差机理研究[J]. 电气技术, 2022, 23(5): 39-44, 54. Zhu Bofeng, Lu Junyong, Zhang Xiao, et al.Charging error analysis of multi parallel pulse power modules based on leakage reactance of high frequency transformer[J]. Electrical Engineering, 2022, 23(5): 39-44, 54. [6] 李化, 王文娟, 李智威, 等. 2.7MJ/m3高储能密度脉冲电容器的研制[J]. 高压电器, 2016, 52(3): 69-73, 80. Li Hua, Wang Wenjuan, Li Zhiwei, et al.Development of high energy density (2.7 MJ/m3) pulse capacitor[J]. High Voltage Apparatus, 2016, 52(3): 69-73, 80. [7] O'Dwyer J J. Theory of dielectric breakdown in solids[J]. Journal of the Electrochemical Society, 1969, 116(2): 239. [8] Zebouchi N, Malec D.Combination of thermal and electromechanical breakdown mechanisms to analyze the dielectric breakdown in polyethylene terephthalate[J]. Journal of Applied Physics, 1998, 83(11): 6190-6192. [9] Ieda M, Sawa G, Kato S.A consideration of Poole-Frenkel effect on electric conduction in insulators[J]. Journal of Applied Physics, 1971, 42(10): 3737-3740. [10] 李智威, 李化, 杨佩原, 等. 不同场强下金属化聚丙烯膜电容器泄漏特性[J]. 电工技术学报, 2013, 28(9): 274-280. Li Zhiwei, Li Hua, Yang Peiyuan, et al.Leakage characteristic of metallized polypropylene film capacitors under different electric fields[J]. Transactions of China Electrotechnical Society, 2013, 28(9): 274-280. [11] Reed C W, Cichanowskil S W.The fundamentals of aging in HV polymer-film capacitors[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 1994, 1(5): 904-922. [12] Sarjeant W J, Zirnheld J, MacDougall F W. Capacitors[J]. IEEE Transactions on Plasma Science, 1998, 26(5): 1368-1392. [13] Lee Y P, Kong M G.Numerically established correlation in electrical responses of polymer film capacitors to AC and pulsed voltages[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2001, 8(6): 880-888. [14] Kong M G, Lee Y P.Electrically induced heat dissipation in metallized film capacitors[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2004, 11(6): 1007-1013. [15] Qin S, Ho J, Rabuffi M, et al.Implications of the anisotropic thermal conductivity of capacitor windings[J]. IEEE Electrical Insulation Magazine, 2011, 27(1): 7-13. [16] Tortai J H, Denat A, Bonifaci N.Self-healing of capacitors with metallized film technology: experimental observations and theoretical model[J]. Journal of Electrostatics, 2001, 53(2): 159-169. [17] Kong Zhonghua, Lin Fuchang, Jang Y, et al.Study of temperature rise of metallized capacitors applied in repetitive pulse[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2009, 16(4): 1100-1105. [18] Li Zhiwei, Li Hua, Huang Xiang, et al.Temperature rise of metallized film capacitors in repetitive pulse applications[J]. IEEE Transactions on Plasma Science, 2015, 43(6): 2038-2045. [19] 李化, 陈麒任, 李浩原, 等. 交流高压金属化膜电容器温升特性和优化设计[J]. 高压电器, 2018, 54(1): 1-8. Li Hua, Chen Qiren, Li Haoyuan, et al.Temperature rise characteristic and design optimization of AC high voltage metallized film capacitor[J]. High Voltage Apparatus, 2018, 54(1): 1-8. [20] 邱昊, 高秀华, 邱林俊, 等. 直流支撑电容器工作温升特性研究及优化设计[J]. 电子元件与材料, 2023, 42(8): 969-974, 981. Qiu Hao, Gao Xiuhua, Qiu Linjun, et al.Research and optimization on operating temperature rise of DC-link capacitor[J]. Electronic Components and Materials, 2023, 42(8): 969-974, 981. [21] 岳国华, 杜志叶, 孟圣淳, 等. 基于电热耦合的干式直流电容器温升分布不均匀特性分析及优化[J]. 高电压技术, 2022, 48(12): 4915-4924. Yue Guohua, Du Zhiye, Meng Shengchun, et al.Analysis and optimization of non-uniform temperature rise distribution of dry-type DC capacitor based on electro-thermal coupling[J]. High Voltage Engineering, 2022, 48(12): 4915-4924.
2025, Vol. 40 
