高电压技术2012，Vol.38Issue(2)：451-456,6.
换流变压器极性反转非线性电场分析
Analysis of Nonlinear Electric Field of Converter Transformer Under Polarity Reversal Voltage
摘要
Abstract
The conductivity of insulation oil and paper of the converter transformer is influenced by electric field strength,temperature and pressure etc.In order to study the influence of electric dependent conductivity on electric field distributions,the nonlinear characteristics between electric field strength and conductivity of the oil is fitted by an exponential curve.Using the new nonlinear curve,the transient nonlinear electric field of a ±500 kV converter transformer under PR（polarity reversal） voltage is calculated by the C-N（Crank-Nicolson） method.The numerical results under linear and nonlinear conditions show that,when we consider the 1 minutes duration of the PR process,the linear maximum electric field strengths at the end of the ramp voltage of the PR are almost equal to the results under the step voltage,while the nonlinear maximum electric field strengths at the end of the ramp voltage of the PR are about 50 percent less than the results under the step voltage.The phenomena of the less value under the nonlinear condition are explained by the acceleration of the space charges under the electric dependent conductivity.关键词
换流变压器/极性反转/非线性/电场强度/空间电荷/有限元Key words
converter transformer/polarity reversal/nonlinear/electric field strength/space charge/finite element分类
信息技术与安全科学引用本文复制引用
刘刚,李琳,李文平,李博,孙优良,李金忠..换流变压器极性反转非线性电场分析[J].高电压技术,2012,38(2):451-456,6.基金项目
国家自然科学基金 （）
国家电网公司科技项目（SGKJJSKF[2009]）~~ （）
