典型空气间隙放电电压修正的试验研究

Experimental Research on Typical Air Gap Test Voltage Correction

为深入了解不同海拔条件下空气间隙放电电压水平及其海拔修正关系,选择棒–板典型间隙,在昆明和南宁的高压试验场和实验室进行同等布置下的对比试验。试验在昆明特高压户外试验场、昆明超高压基地户外试验场和南宁高压大厅开展,内容包括0.8～1.8m间隙距离下正极性直流电压放电试验,1.5～4.5m间隙距离下正、负极性雷电冲击(lightning impulse,SI)放电试验以及1.5～5m间隙距离下正、负极性操作冲击(switching impulse,SI)放电试验。此外,在昆明获得了最长间隙距离至10m的正极性雷电、操作冲击放电试验数据。根据试验数据分析,讨论了大气条件影响和海拔修正。基于g参数的大气条件修正方法对正极性放电在昆明和南宁2地不同海拔条件下的计算结果重合性较好,而对负极性放电有较大偏差。最后,提出了棒–板间隙在直流、雷电、操作3种电压类型下、海拔高度2100m以下的放电电压海拔修正计算公式。

ACT： For the purpose of obtaining air gap discharge voltage and its correction in different altitudes, typical rod-to-plane air gap was selected, and comparative experiments were conducted under the same configuration condition in Kunming and Nanning. The experiments were carried out at Kunming UHV outdoor test site, Kunming EHV outdoor test site and Nanning high voltage test hall, including direct current （DC） voltage discharge tests with gap length of 0.8-1.8 m, lightning impulse （LI） voltage discharge tests with gap length of 1.5-4.5 m, and switching impulse （SI） voltage discharge tests with gap length of 1.5-4.5 m. In addition, positive LI and SI discharge test data with gap length up to 10m were obtained in Kunming. The influence of atmospheric condition and altitude correction were discussed based on the test data. The atmospheric condition correction results based on g parameter for positive discharge agree with each other well in different altitudes of Kunming and Nanning, but for the correction results of negative discharge, big errors might occur. Finally, altitude correction parameters of rod-to-plane air gap discharge voltage at high altitude of 2 100 m in voltages ofDC, LI and SI were proposed.