气压和湿度对水轮发电机定子线棒端部局部放电特性的影响  

Effect of Air Pressure and Humidity on the Partial Discharge Characteristics of Hydro Generator Stator Bar End

作　　者：陈科元 马山刚[1] 金福宝[1] 冷雪健 CHEN Keyuan;MA Shangang;JIN Fubao;LENG Xuejian(College of Energy and Electrical Engineering,Qinghai University,Xining 810016,China;State Grid Shaanxi Electric Power Co.,Ltd.,Shangluo Power Supply Company,Shangluo 726000,China)

机构地区：[1]青海大学能源与电气工程学院,西宁810016 [2]国网陕西省电力有限公司商洛供电公司,陕西商洛726000

出　　处：《电瓷避雷器》2024年第6期1-10,共10页Insulators and Surge Arresters

基　　金：国家自然科学基金项目(编号:51865049);青海省科技厅基础研究计划项目(编号:2020-ZJ-708)。

摘　　要：高海拔地区水轮发电机定子线棒端部局部放电强度会受气压和湿度等环境参数的影响。因此,文中设计制作了F级10 kV水轮发电机定子线棒端部主绝缘内部气隙缺陷模型、防晕层脱落缺陷模型以及主绝缘磨损与油污缺陷模型,开展了3种缺陷模型的放电特性研究,并基于脉冲电流法和臭氧检测法进行不同气压和湿度条件下局部放电试验,探究气压和湿度对定子线棒端部缺陷部位局部放电的影响规律。结果表明,气压降低会显著加剧不同缺陷类型的放电强度,但气压对内部气隙缺陷的影响较小;湿度增加会明显减缓各缺陷类型的放电发展进程,外绝缘缺陷受抑制作用更大,相较而言,气压的改变对缺陷部位局部放电的影响大于湿度的变化。对于不同故障缺陷类型,臭氧浓度的变化范围明显不同,采用臭氧浓度评判局部放电强度具有可行性,但低压和高湿环境在降低臭氧生成速率的同时也促进了臭氧的分解,导致臭氧浓度总体处于较低水平。研究结果可为提升高海拔地区水电站定子线棒局部放电在线监测水平和绝缘评估能力提供借鉴意义。The partial discharge intensity at the end of hydro generator stator bars at high altitude is affected by environmental parameters such as air pressure and humidity.Therefore,the author designed and fabricated the F-class 10 kV hydro generator stator bar end main insulation internal air gap defect model,anti-scorch layer detachment defect model,and the main insulation wear and oil defect model,and carried out the study of the discharge characteristics of the three defect models.Based on the pulsed-current method and the ozone detection method,the partial discharge test under different air pressure and humidity conditions is carried out,and investigate the effect of air pressure and humidity on the defective parts of the stator bar end.The results show that the decrease of air pressure will significantly aggravate the discharge intensity of different defect types,but the effect of air pressure on the internal air gap defects is smaller;the increase of humidity will significantly slow down the development of the discharge process of each defect type,and the external insulation defects are more inhibited,compared to the change of air pressure on the defective parts of the localized discharge is greater than the change of humidity.For different types of defects,the ozone concentration varies significantly,and it is feasible to use the ozone concentration to judge the partial discharge intensity,but the low-pressure and high-humidity environments promote the decomposition of ozone while decreasing the ozone generation rate,resulting in the overall ozone concentration being at a low level.The results of the study can provide a reference for improving the online monitoring level of partial discharges in stator bars of hydropower stations at high altitude and the insulation assessment capability.

关 键 词：气压 湿度 定子线棒 局部放电 臭氧浓度 

分 类 号：TV734.2[水利工程—水利水电工程] TM855[电气工程—高电压与绝缘技术]