三种工况对变压器套管潮气入侵绝缘特性的影响  

Influence of Moisture Ingress on the Insulation Characteristic in Oil-immigrated Paper Bushings Under Three Test Condition

作　　者：戴佺民 齐波[1,2] 李成榕[1,2] Niyomugabo E.Ladislas 卓然 傅明利 

机构地区：[1]华北电力大学新能源电力系统国家重点实验室,北京102206 [2]华北电力大学高电压与电磁兼容北京市重点实验室,北京102206 [3]南方电网科学研究院有限责任公司,广州510663

出　　处：《高电压技术》2018年第2期554-560,共7页High Voltage Engineering

基　　金：国家高技术研究发展计划(863计划)(2015AA050204);国家自然科学基金(51477052)~~

摘　　要：现有规程中套管试验方法与实际工况差异较大,仅考虑电压单一应力的短时作用,难以满足越来越高的设备可靠性需求。针对此问题研制了一种新型变压器套管复合工况试验考核装置;研究了受潮早期套管在阶梯升压、运行电压、运行电压电流复合作用3种工况下的介质损耗角正切值（tanδ）、局部放电的变化规律,实现了阶梯升压、运行电压、运行电压电流复合三种试验工况下变压器套管长期带电考核。研究结果表明：在套管受潮早期,1）阶梯升压下tanδ呈现增长的趋势,但未超过规程规定值,局部放电基本不变;2）恒定运行电压作用下tanδ随时间呈现＂先增长、后下降、再增长、再下降＂的规律,但局部放电变化不明显;3）复合工况下tanδ变化规律与恒定运行电压作用的变化规律相似,tanδ值有所降低,但局部放电现象明显。利用复合工况对套管绝缘受潮缺陷的考核最为严酷,更有利于发现缺陷套管。该试验装置为变压器套管的缺陷检测及质量考核提供了一种新的试验考核方法。The currently existing test methods of transformer bushing can not meet the needs of responsibility of bushing under only voltage stress due to big gaps with actual conditions. In view of the above problem, we designed a new test device of combination operating condition for bushing and applied three test conditions including the voltage step-by-step, operating voltage, and combined voltage and current to 72.5 k V transformer bushings. The parameters of partial discharge and tanδ were measured for the damped bushing model. In the early state of moisture ingress into bushing, the tendency of tanδ-U increases with the voltage step-by-step condition and does not exceed the test law for moisture bushing. Tendency of tanδ-U increases in waves under the voltage long time and combined voltage condition at the same time. But partial discharge appears obviously under the combined condition. It is suggested that the new test method of the combined voltage and current condition is more beneficial to detect the moistened bushings. It provides a new test method for the quality assessment.

关 键 词：变压器套管 复合工况 潮气入侵 局部放电 介质损耗角正切 故障诊断 

分 类 号：TM41[电气工程—电器]