基于地电波幅值经验累积分布特性的高压开关柜状态判断及运维策略

HV Switchgears State Judging and Operation and Maintenance Strategy Based on Empirical Cumulative Distribution Characteristics of TEV PD Levels

目前国内各运行单位均采用国外经验判断高压开关柜的局部放电情况,缺乏本地化的开关柜状态判断方法。为此基于广州地区30773组在运高压开关柜的局部放电数据,获得了高压开关柜局部放电地电波现场测试值的经验累积分布函数。比较了广州与国外高压开关柜局部放电地电波测试值的经验累积分布函数典型特征的差异。根据25%、10%及5%划分依据,国外某数据库中对应的经验阈值分别为19dB·mV、29dB·mV、35dB·mV,而广州地区数据库中对应的经验阈值分别为13dB·mV、23dB·mV、32dB·mV,表明以国外数据库的分布规律获得的开关柜局部放电地电波测试值判断经验不完全适用于本地区。基于经验累积分布函数,综合考虑了设备的故障风险概率和运维成本等因素,提出了更加灵活、技术经济效益可靠性更优、更加符合本地区的高压开关柜状态判断原则及运维策略。

At present,domestic operating companies judge partial discharge conditions of high voltage switchgear by foreign experi-ence,and are lacking in localized switchgear status judging methods. According to the partial discharge data of 30 773 running high voltage switchgears in Guangzhou,a series of novel empirical cumulative distribution functions （ECDFs）based on on-site transient earth voltage （TEV）data of high voltage switchgears are proposed. Differences of typical features between local and foreign ECDFs of on-site TEV data are compared. According to the distribution criteria of 25%,10% and 5%,the foreign thresholds are 19 dB＆#183;mV,29 dB＆#183;mV and 35 dB＆#183;mV,whereas the local empirical thresholds are 13 dB＆#183;mV,23 dB＆#183;mV and 32 dB＆#183;mV. The result illustrates that the foreign experience on the thresholds may not be suitable for local judgment. Based on the ECDFs,the suitable local on-site TEV tests criteria and maintenance strategy considering the risk of failure probability and the maintenance cost are concluded,which is more flex-ible and reliable.