摘要
为研究换流变压器油纸绝缘结构在直流电压下的油流带电特性,在实验室内开展了直流电压下典型平板油纸绝缘结构油流带电特性的研究。试验研究结果表明:流速和外施电压对冲流电流的影响与温度有关;在无外施电压作用时,低温下冲流电流随流速呈线性增加、高温下呈幂函数关系增加。外施直流电压对冲流电流具有显著的影响,随外施直流电压的升高冲流电流呈先上升后下降的趋势,峰值电流处的电压随油流速度的提高而上升,随温度的升高而下降。对试验结果的理论分析表明:无外施电压时冲流电流与流速的关系特性受油流状态影响;当有外施直流电压作用时,电场作用下的迁移电流和泄漏电流共同决定了冲流电流的大小;温度通过影响油流状态、油纸绝缘中的电场分布和离子迁移率而影响油流带电特性。
In order to investigate the flow electrification characteristics of the oil-pressboard insulation in converter transformer under the DC voltage,the experiment research on flow electrification under DC voltage was carried out with the typical plane oil-pressboard insulation structure.The results show that the influence of oil flow velocity and applied voltage on streaming current was related to temperature.Without external energizing voltage,the streaming current increases linearly with flow velocity at low temperature.At high temperature,there＇ s a function between streaming current and different power of flow velocity.The applied DC voltage has great influence on the streaming current,and the streaming current increases first then decreases with DC voltage.The voltages corresponding to the peak current increase with the rise of oil flow velocity and decrease with the increase of temperature.Theoretical analysis of the test results show that the relationship between the amplitude of streaming current and velocity is affected by the oil flowing state when without external energizing voltage.The magnitude of streaming current is decided by migration current and leakage current when with the applied voltage.The temperature influences the flow electrification characteristics by affecting the oil flowing state,the electric field distribution in the oil-paper insulation,and the ion migration speed.
出处
《电机与控制学报》
EI
CSCD
北大核心
2015年第2期14-19,共6页
Electric Machines and Control
基金
国家自然科学基金(51277047)
国家自然科学基金青年基金项目(51407051)
黑龙江省杰出青年基金资助项目(JC2010-09)
关键词
直流输电
换流变压器
油纸绝缘
油流带电
离子迁移
DC transmission
converter transformer
oil-paper insulation
flow electrification
ion migration
