不同老化条件对开关柜绝缘件绝缘性能的影响研究

Research on the Influence of Different Aging Conditions on the Insulation Performance of Insulation in Switchgear

开关柜是电力系统中重要的电力设备,开关柜内绝缘件会受到实际工况中不同老化条件(污秽、潮湿凝露、冷热循环、热老化等)的影响而产生老化现象。为了探究不同老化条件对开关柜绝缘件绝缘性能的影响,基于开关柜运行的实际工况,综合考虑了开关柜内导电回路发热、潮湿及凝露、冷热循环、污秽等多个因素对柜内绝缘件性能老化的影响过程,通过开展不同因素组合下的模拟试验,对不同老化条件处理下绝缘件表面局放、耐压进行测量。试验结果表明,污秽老化会使绝缘子表面起晕电压及熄灭电压降低,同时降低绝缘子的耐压能力,且污秽越严重,绝缘子耐压能力下降越明显;加入潮湿凝露老化条件会使绝缘子表面的起晕电压及熄灭电压大幅度降低,同时局放量大大增加;加入热老化后,绝缘子表面起晕电压和熄灭电压进一步减弱。同时,热老化会使套管及触头盒的起晕电压和熄灭电压明显下降,并使套管和触头盒的耐压性能略微降低。

Switchgear is an important power equipment in power system.The insulation components in the switch⁃gear will be affected by different aging conditions(pollution aging,moisture condensation aging,cold and hot cycle aging,thermal aging,etc.)under actual working conditions.In order to explore the influence of different aging condi⁃tions on the insulation performance of switchgear insulation parts,based on the actual operating conditions of the switchgear,a comprehensive consideration of the influence process of the conductive circuit heating,moisture and condensation,cold and hot circulation,pollution and other factors on the performance of the insulation aging in the switchgear.The influence process of insulation performance aging of switchgear caused by conductive circuit heating,moisture and condensation,cold and hot circulation,pollution and other factors is comprehensively considered.By carrying out simulation tests under different combinations of factors,the partial discharge and withstand voltage,of the insulation under different aging conditions are tested to assess the impact of various aging factors on the insulation performance of the switchgear.The experimental results show that the dirty aging which reduces the halo and extinc⁃tion voltage of the insulator can also reduce the withstand voltage of the insulator.The more serious the dirty aging is,the more obvious declinating of the insulator’s withstand voltage is.With consideration of the moisture condensation aging,the halo and extinguishing voltage of the insulator will be greatly reduced,as well as the partial discharge value will be greatly increased.If further considering the thermal aging,the halo and extinguishing voltage of the insulator is further weakened.Meanwhile,the thermal aging can reduce the halo voltage and extinction voltage of the bushing and contactbox,and slightly reduce the withstand voltage performance.