摘要
高压电气设备在遭受过电压侵袭时绝缘将同时承受运行电压与过电压的共同作用,严重威胁设备的运行安全。考虑与实际工程背景相切合,该文设计了一套冲击叠加相位可控的交流与冲击叠加试验系统,对工频交流与标准操作冲击叠加电压下SF6气体中沿面局部放电特性进行了研究分析。当交流电压分别为试品的90%局部放电起始电压(PDIV)与110%PDIV时,在工频相位0°~360°,以45°为步长叠加峰值为两倍交流PDIV的操作冲击。试验结果表明,冲击叠加相位对交流电压下沿面局部放电特性影响显著。当在工频相位45°~135°之间叠加冲击时,冲击过后交流电压下的局部放电被激发或得到增强,而在其他相位叠加冲击时对交流电压下的局放无明显影响。冲击对交流局放的影响具有明显的极性效应,冲击过后仅交流电压负半周发生明显放电或放电得到增强,而对正半周的局放无激发或促进作用。冲击对交流下局放的影响与交流电压的幅值相关,交流电压幅值越高,在相同相位叠加冲击时所激发的局放幅值与次数越大。
When high voltage electrical equipment is subject to overvoltage attack,the insulation will be stressed by AC and overvoltage at the same time,which seriously threatens the reliability of equipment operation.Considering the actual engineering operation,this paper designed a set of AC and impulse superimposed voltage test system with fully controllable superposition phase,and studied the surface partial discharge characteristics in SF6 gas under AC and standard switching impulse voltage.When the AC voltage is 90%and 110%of partial discharge inception voltage(PDIV)of the test sample respectively,the switching impulse with amplitude of about twice of PDIV was superimposed on different phases of AC voltage.The phase of impulse superposition was changed from 0°to 360°with a step size of 45°.The test results show that the phase of impulse superposition has a significant effect on the AC surface partial discharge.When the impulse is superimposed from 45°to 135°of AC voltage,partial discharge(PD)under the AC voltage is excited or enhanced after impulse,but there is no influence on the AC PD activities when the impulse is superimposed on other phase.The effect of the impulse on the AC PD activities has a significant polarity effect,the AC PD is only excited or enhanced in the negative half cycle of AC voltage after impulse,but there is no obvious effect on PD in the positive half cycle.The effect of impulse on AC PD activities is related to the amplitude of AC voltage.The higher the amplitude of AC voltage,the greater the amplitude and number of PD excited by impulse when the same phase is superimposed.
作者
何聪
张芊
曹铎耀
袁文泽
李军浩
He Cong;Zhang Qian;Cao Duoyao;Yuan Wenze;Li Junhao(State Key Laboratory of Electrical Insulation and Power Equipment Xi’an Jiaotong University,Xi’an 710049 China)
出处
《电工技术学报》
EI
CSCD
北大核心
2020年第8期1807-1817,共11页
Transactions of China Electrotechnical Society
基金
国家自然科学基金资助项目(51877169)。
关键词
高压电气设备
过电压
交流叠加冲击
SF6
沿面局部放电
High voltage electrical equipment
overvoltage
AC superimposed impulse
SF6
surface partial discharge
作者简介
何聪,男,1990年生,博士研究生,研究方向为电气设备局部放电检测。E-mail:469153729@qq.com;通信作者:李军浩,男,1980年生,教授,博士生导师,研究方向为电力设备在线监测、电力设备绝缘故障诊断与状态评估以及电力设备新型试验等。E-mail:junhaoli@mail.xjtu.edu.cn。
