B-H Curve Based on Core and Asymmetric Magnetizing Current in DC-Biased Transformers
Guo Mansheng1 Mei Guihua2 Liu Dongsheng1 Liu Yancun2 Cheng Zhiguang1 Zhang Xile1
1. Baoding Tianwei Baobian Electric Co. Ltd. Baoding 071056 Chinab 2. Electric Power Research Institute of Guangdong Power Grid Corporation Guangzhou 510600 China
Abstract：Based on the direct current biased magnetization properties for transformer core, an engineering-oriented practical method to calculate the asymmetric magnetizing current in DC biased large power transformer is presented in this paper.Firstly, the characteristic curves involved ?-I、B-H related to different DC biasing level are established by experiments on the transformer model, which reduced in scale to a linear dimentional ratio of approximately 1/50 relative to a 250MVA class transformer; Secondly, the effect on the curves due to biased magnetic flux are considered by simulation. Lastly, the method are developed to determine the asymmetric magnetizing current.The experiments are in accordance with the simulation results, confirming the validity of the proposed method.
郭满生, 梅桂华, 刘东升, 刘艳村, 程志光, 张喜乐. 直流偏磁条件下电力变压器铁心B-H曲线及非对称励磁电流[J]. 电工技术学报, 2009, 24(5): 46-51.
Guo Mansheng, Mei Guihua, Liu Dongsheng, Liu Yancun, Cheng Zhiguang, Zhang Xile. B-H Curve Based on Core and Asymmetric Magnetizing Current in DC-Biased Transformers. Transactions of China Electrotechnical Society, 2009, 24(5): 46-51.
[1] 王祥珩, 徐伯雄. 变压器的偏磁问题[J]. 变压器, 1992, 19(8): 11-14. [2] Lahtinen M, Elovaara J. GIC occurrences and GIC test for 400kV system transformer[J]. IEEE Trans. on Power Delivery, 2002, 17(2): 555-561. [3] 钟连宏, 陆培均, 仇志成, 等. 直流接地极电流对中性点直接接地变压器影响[J]. 高电压技术, 2003, 29(8): 12-13, 28. [4] 曾连生. 直流接地极电流对电力变压器的影响[J].电力建设, 2004, 25(12): 22-24. [5] 尚春. HVDC地中电流对交流变压器影响的抑制措施[J]. 高电压技术, 2004, 30(11): 52-54. [6] Takasu N, Oshi T, Miyawaki F, et al.An experimental analysis of DC exitation of transformers by geomagnetically induced currents[J]. IEEE Trans. on Power Delivery, 1994, 9(2): 1173-1179. [7] 李晓萍. 变压器直流偏磁问题的研究[D]. 武汉: 武汉大学, 2006. [8] Price P R. Geomagnetically induced current effects on transformers[J]. IEEE Trans. on Power Delivery, 2002, 17(4): 1002-1008. [9] Cheng Z, Hao R, Takahashi N, et al. Engineering- oriented benchmarking of problem 21 family and experimental verification[J]. IEEE Trans. on Magn., 2004, 40(2):1394-1397. [10] Picher P, Bolduc L, Dutil A, et al. Study of the acceptable DC current limit in core-form power transformers[J]. IEEE Trans. on Power Delivery, 1997, 12(1): 257-263. [11] Yoshida T, Nakano M, Miyagi D, et al. Development of measuring equipment of DC-biased magnetic properties using open type single sheet tester[J]. IEEE Trans. on Magn., 2006, 42(10): 2846-2848.
2009, Vol. 24 
