35kV开关柜电晕试验研究及分析应用

Experimental Study and Analysis of 35kV Switchgear Corona Application

目前,绝大多数35kV电压等级金属封闭开关柜受"典设"和现有常规技术等因素限制,柜内导体间距无法满足DL404-2007《3.6kV^40.5kV交流金属封闭开关设备和控制设备》和国网公司"十八项反措(修订版)"中35kV开关柜柜内空气绝缘净距离应大于300mm的要求。另一方面,按照传统观念35kV电压等级开关柜为中压设备领域,因此,在生产制造、现场安装等方面往往未按高电压等级理念来对待,其内部电场和工艺设计、制造以及安装试验等要求明显偏低,突出表现在正常运行电压下开关柜即出现明显电晕放电现象,从而导致开关柜耐受电压降低,并诱发绝缘故障的发生。本文研究分析35kV开关柜产生电晕的原因及现场试验方法,提出35kV开关柜在出厂、并柜、交接时电晕试验标准,讨论分析产生电晕现象的原因,为有效解决省网35kV开关柜运行中出现的绝缘问题、降低故障率、提高开关柜的运行水平提供技术标准。

Currently, the vast majority of 35kV voltage metal-enclosed switchgear by the ＂Code set＂ and the existing limitations of conventional technology and other factors, the cabinet conductor spacing not meet DL404-2007 ＂3.6kV - 40.5kV AC metal-enclosed switchgear and control equipment.＂ and State Grid company ＂eighteen anti-measures （revised edition）＂ in the 35kV air-insulated switchgear cabinet net distance should be greater than 300mm requirements. On the other hand, according to the traditional concept of 35kV voltage levels for medium voltage switchgear equipment in the field, therefore, in terms of manufacturing, site installation often fails to deal with the concept of high voltage level, the internal electric field and process design, manufacture and installation tests require significantly lower, outstanding performance under normal operating voltage switchgear appears obvious corona discharge phenomenon, leading to lower withstand voltage switchgear and induce insulation failure. This paper analyzes 35kV switchgear corona causes and field test methods proposed 35kV switchgear at the factory, and cabinets, when the transfer corona test standards, discussion and analysis of the causes corona phenomenon, as an effective solution to the provincial network 35kV switchgear insulation problems occurred in operation, redtice the failure rate and increase the operational level of the switchgear provides technical standards.