配电网用气体间隙开关触发腔性能劣化进程及剩余寿命预测方法  

Performance Degradation and Remaining Trigger Lifetime Prediction of Gas Gap Switch’Trigger Cavity for Distribution Network

作　　者：董冰冰 陈子建 Dong Bingbing;Chen Zijian(School of Electrical Engineering and Automation Hefei University of Technology,Hefei 230009,China)

机构地区：[1]合肥工业大学电气与自动化工程学院,合肥230009

出　　处：《电工技术学报》2024年第13期4127-4138,共12页Transactions of China Electrotechnical Society

基　　金：中央高校基本科研业务费专项资金和国家自然科学基金(52107142)资助项目。

摘　　要：气体间隙开关重复触发动作导致其触发腔的机械性能、电气性能降低,在配电网快速控制与保护应用场景中的影响或将更加显著,亟须开展触发腔性能劣化及其寿命预测研究,为此搭建了气体间隙开关触发放电研究平台。研究结果表明,随着触发放电次数的累积,触发腔针电极处内径、喷口直径与内壁表面粗糙度均逐渐增大,喷口内壁出现凹坑、凸起点,针电极处的烧蚀孔洞由“点—线—面”发展,引起气体开关触通过程中的等离子体喷射特性参数(喷射高度、喷射直径、喷射面积)逐渐减小,触通时延、击穿时延均明显增大。在强绝缘、强电负性SF6触发环境中,计及放电烧蚀分解产物的电负性效应,致其喷射等离子体发展过程受到明显抑制,显著制约了触发寿命。选取喷射高度为预测因子,建立基于长短期记忆神经网络(LSTM)的气体开关剩余触发寿命预测模型,模型预测值与试验值间的方均根误差、平均绝对百分比误差分别低至0.063、0.055,剩余触发寿命预测误差在10%以内。研究结果可为气体开关运行稳定性及寿命预测提供参考。The mechanical and electrical performance of gas gap switch’trigger cavity inevitably decreases caused by repeated trigger discharge,causing a serious problem of trigger failure.In order to achieve stable trigger conduction of the gas gap switch,the study of the degradation process of the gas switch trigger performance under repeated trigger discharge was carried out based on the trigger lifetime research platform,the trigger conduction parameters strongly correlated with the deterioration process of the gas switch trigger cavity performance were obtained.Ultimately,a trigger lifetime prediction model of gas gap switch based on long short term memory(LSTM)network was established to predict the remaining trigger lifetime.From the experimental results,it can be concluded:(1)At the early stage of trigger lifetime,the plasma jet height is up to 10.1 mm,leading to the excellent trigger conduction performance of gas gap switch,with breakdown delay and contact delay as low as 68μs and 77μs.Under the effect of intense ablation along the surface arc current,the inner diameter at pin electrode and the nozzle diameter of trigger cavity increases gradually,the pressure difference between the inside and outside of the trigger cavity nozzle decreases,leading to a decrease in the plasma jet characteristics parameters,weakening the distortion effect of the background electric field in the main gap,resulting in the increase of the breakdown delayΔt1 and trigger delayΔt2.Within 500~800 trigger discharge times,pre-breakdown effect occurs obviously during the trigger conduction process of gas gap switch,leading to the breakdown delay and trigger delay disperse notably with the fluctuation value up to 30μs.At the end of trigger lifetime,the jet height is as low as 5.5 mm,which cannot meet the needs for stable trigger conduction of gas gap switch,causing the trigger failure of gas gap switch with a trigger lifetime of up to 1200 times.(2)Under repeated trigger discharge,the ablation holes appear on the inner wall of trigger cav

关 键 词：气体间隙开关 等离子体喷射 重复触发放电 烧蚀累积 寿命预测 配电网 

分 类 号：TM470[电气工程—电器]