Abstract:Aiming at the calculation of the strand current and circulation current losses in the transposition stator windings of large hydro generator, a new analytic method is proposed which is called the improved leakage susceptible electromotive potential method. The method solves the issue of traditional method that the unreasonable assumption of leakage magnetic field with incomplete circuit constraints which also ignored the actual path of the transposition strands. The equivalent circuit of each strand in the stator bar is considered as a branch which is composed of a resistance and leakage inductive electromotive force. The calculation methods of leakage inductive electromotive force in slot part and end part of the strand are given respectively. Taking a 140 MW large hydro generator for instance, the current distribution of each strand which had 360° complete transposition and deficient transposition in the stator slot is calculated by the improved leakage susceptible electromotive potential method. Additionally, the circulation current losses can be solved according to the current distribution. By comparing with the experimental results, the distribution of the strand current and the circulation current losses are basically consistent, which proves the correctness of the analytical algorithm.
梁艳萍,乔雪,边旭,李加星. 改进漏感电动势法计算换位线棒股线电流及环流损耗[J]. 电工技术学报, 2017, 32(17): 164-171.
Liang Yanping, Qiao Xue, Bian Xu, Li Jiaxing. Improved Method of Leakage Susceptible Electromotive Potential to Calculate Strand Current and Circulation Current Losses in Transposition Windings. Transactions of China Electrotechnical Society, 2017, 32(17): 164-171.
[1] 许善椿, 吴祚潭. 大型发电机定子线棒的新型换位技术(Ⅰ)[J]. 大电机技术, 1992(1): 1-5. Xu Shanchun, Wu Zuotan. A new transposition technique of the stator bars of large generators(I)[J].Large Electric Machine and Hydraulic Turbine, 1992(1): 1-5. [2] 师元康, 姜振超, 赵书涛. 基于内部温度的继电保护装置时变失效率研究[J]. 电力系统保护与控制, 2016, 44(4): 123-128. Shi Yuankang, Jiang Zhenchao, Zhao Shutao. Research on time-varying failure rate of protection devices based on internal temperature[J]. Power System Protection and Control, 2016, 44(4): 123-128. [3] 罗剑锋, 唐轶, 陈奎, 等. 基于发热-散热积累模型的电动机过载保护研究[J]. 电力系统保护与控制, 2010, 38(3): 95-98. Luo Jianfeng, Tang Yi, Chen Kui, et al. Study on motor over-load protection based on heat accumulation-emission model[J]. Power System Protection and Control, 2010, 38(3): 95-98. [4] 梁艳萍, 柳杨, 王晨光. 大型水轮大电机定子绕组新型组合换位方法分析[J]. 中国电机工程学报, 2016, 36(11): 3092-3100. Liang Yanping,Liu Yang,Wang Chenguang. Analysis on a new method of combination transposition for the stator windings of the hydro-generators[J]. Proceedings of the CSEE, 2016, 36(11): 3092-3100. [5] Liang Yanping, Chen Yuanqi.Circulating current losses analysis and improved incomplete transposition for stator bars in large hydro-generators[J]. IET Electric Power Applications, 2016, 10(3): 125-132. [6] 周登, 姚缨英. 多截面场路耦合法和解析法对比分析水轮机定子线棒4种换位下的环流[J]. 机电工程, 2015, 32(12): 1600-1605. Zhou Deng, Yao Yingying.Comparison of multi-section method coupled field-circuit and analytical method for the analysis of the circulating current of 4 kinds of transposition in the stator of a hydraulic turbine[J]. Journal of Mechanical and Electrical Engineering, 2015, 32(12): 1600-1605. [7] 夏盛. 大型水轮发电机定子线棒换位研究[D]. 杭州:浙江大学, 2013. [8] Fujita M, Kabata Y, Tokumasu T, et al. Circulating currents in stator coils of large turbine generators and loss reduction[J]. IEEE Transactions on Industry Applications, 2009, 45(2): 685-693. [9] 杜鹏程, 徐习东. 高速磁浮列车定子绕组感应电动势研究[J]. 电力系统保护与控制, 2012, 40(6): 109-118. Du Pengcheng, Xu Xidong. Research of electromotive force in stator of high speed maglev vehicle[J]. Power System Protection and Control, 2012, 40(6): 109-118. [10]Bian Xu, Liang Yanping. Circuit network model of stator transposition bar in large generators and calculation of circulating current[J]. IEEE Transactions on Industrial Electronics, 2015, 62(3): 1392-1399. [11]杨立超. 大型水轮发电机定子线棒换位与环流损耗分析计算[D]. 哈尔滨:哈尔滨理工大学, 2014. [12]梁艳萍, 边旭, 于鸿浩, 等. 多线棒不完全换位定子绕组环流损耗的分析计算[J]. 中国电机工程学报, 2013, 33(24): 168-174. Liang Yanping, Bian Xu, Yu Honghao,et al. Analysis and calculation on circulating current losses instator windings with multiple bars per layer of deficient transposition[J]. Proceedings of the CSEE, 2013, 33(24): 168-174. [13]杜灿勋, 桂卫华, 周光厚. 大型全空冷水轮发电机定子线棒损耗和温度场综合计算[J]. 中国电机工程学报, 2012, 32(12): 111-119. Du Canxun, Gui Weihua, Zhou Guanghou. Excessive losses and temperature field calculation of stator coil bars in air-cooled large hydro-generators[J]. Proceedings of the CSEE, 2012, 32(12): 111-119. [14]梁艳萍, 燕秀龙, 于鸿浩. 抽水蓄能电站发电电动机端部磁场及结构件损耗分析计算[J]. 电工技术学报, 2016, 31(6): 21-29. Liang Yanping, Yan Xiulong, Yu Honghao. Analysis and calculation of magnetic field and structure loss in end region of generator-motor for pumped storage power station[J].Transactions of China Electrotechnical Society, 2016, 31(6): 21-29. [15]赵洋, 严波, 曾冲, 等. 大型汽轮发电机定子端部电磁力作用动态响应分析[J]. 电工技术学报, 2016, 31(5): 199-206. Zhao Yang, Yan Bo, Zeng Chong, et al. Dynamic response analysis of large turbogenerator stator end structure under electromagnetic forces[J]. Transactions of China Electrotechnical Society, 2016, 31(5): 199-206. [16]赵争菡, 汪友华, 凌跃胜, 等. 大容量高频变压器绕组损耗的计算与分析[J]. 电工技术学报, 2014, 29(5): 261-265. Zhao Zhenghan, Wang Youhua, Ling Yuesheng, et al. Calculation and analysis of loss in high-capacity high-frequency transformers[J]. Transactions of China Electrotechnical Society, 2014, 29(5): 261-265.