Research on the Formation Mechanism and Suppression Method of Transformer DC Bias
Chen Zhiwei,Bai Baodong,Chen Dezhi,Zhao Xiaoxuan
Theory and Common Technologies of Modern Electrical Equipments Key Lab Special Electric Machines and High Voltage Apparatus Key Lab National Education Ministry and Liaoning Province, Shenyang University of Technology Shenyang 110870 China
Abstract：DC bias phenomena is an abnormal operating state of transformer, research on formation and suppression of transformer DC bias has a great meaning. Actual working state under DC bias is simulated on base of single-phase transformer model which is easily affected by DC bias; the influence on transformer generated by the DC bias phenomenon is studied, the change of excitation current and each harmonic are given before and after DC bias, the reason of even harmonics increased is analysised in detail. A scheme with a function of compensating the power transformer DC bias phenomenon on base of two-phase magnetic material is put forward. The DC bias is directional compensated by controlling the magnetic state of material, simulation of transformer is conducted using ANSOFT and a novel transformer prototype with DC bias compensation function is made, the DC bias compensation experiment is conducted. The simulation and experimental results show that this novel transformer could achieve a good compensation for the DC bias problem which verifies the correctness and feasibility of the proposed scheme.
陈志伟,白保东,陈德志,赵晓旋. 电力变压器直流偏磁现象形成机理及一种抑制措施的研究[J]. 电工技术学报, 2015, 30(14): 208-214.
Chen Zhiwei,Bai Baodong,Chen Dezhi,Zhao Xiaoxuan. Research on the Formation Mechanism and Suppression Method of Transformer DC Bias. Transactions of China Electrotechnical Society, 2015, 30(14): 208-214.
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