交直流复合电压下油纸绝缘内部气隙缺陷局部放电特性  

Partial Discharge Characteristics of Internal Gas-gap Defect in Oil-paper Insulation System under AC and DC Composite Voltage

作　　者：顾朝敏[1] 孙振权[1] 郭治锋[1] 顾乐[1] 李彦明[1] 

机构地区：[1]西安交通大学电力设备电气绝缘国家重点实验室,陕西西安710049

出　　处：《高压电器》2010年第12期9-13,共5页High Voltage Apparatus

基　　金：国家自然科学基金资助项目(50977075)

摘　　要：为了研究换流变压器油纸绝缘的局部放电特性,制作了典型的油纸内部气隙缺陷放电模型,设计了交流和直流电压叠加的实验回路,模拟换流变压器绝缘承受的电压类型。针对实验模型施加不同分量的交流电压和直流电压,用脉冲电流法分别检测该模型局部放电的各个特征参数,进行比较研究。总结了复合电压下油纸气隙放电模型的局部放电脉冲特征规律,并分析了其放电机理。结果表明,交直流复合电压下的油纸绝缘气隙放电具有不同于交流和直流下局部放电新的特点。为实现换流变压器的绝缘状态在线监测与综合评估积累了经验数据。For studying the partial discharge characteristics of oil-paper insulation in converter transformer at DC transmission system,a typical oil-paper partial discharge model-internal defect was made and a testing circuit which DC voltage superposed on AC voltage was designed and built to simulate the voltage component that the converter transformer withstand. Applied different proportion of DC and AC component in the composite voltage and detected the characteristic parameters of the test model with pulse current method to compare and study.Summarized the PD pulse rules of oil-paper insulation gas-gap discharge model under DC AC composite voltage and analyzed its discharge mechanism.The result showed that the PD characteristic of oil-paper insulation gas-gap model under composite voltage is different from that under AC and DC voltage only.Accumulated experience for on-line monitoring and comprehensive evaluation of converter transformer insulation.

关 键 词：换流变压器 油纸绝缘 交直流复合电压 局部放电 放电机理 

分 类 号：TM835.4[电气工程—高电压与绝缘技术]