特高压系统用电容器组开关弧触头失效分析

Failure Analysis of Capacitor Bank Switch Arcing Contact for Ultra-high Voltage System

为了提高特高压系统用电容器组开关弧触头的使用寿命,在拟工况环境下对其进行电寿命实验,发现Cu W/Cu Cr弧触头在近千次开合实验后失效。通过对失效前后弧触头的形貌、成分、组织及性能变化进行分析研究,寻找影响弧触头使用寿命的主要因素。结果表明:特高压系统用电容器组开关弧触头除电弧烧蚀引起弧触头失效外,机械磨损及挤压变形也是影响其使用寿命的关键因素。因此,协同提高耐电弧烧蚀、抗机械磨损及挤压变形的能力是制备高电气寿命触头材料的关键。

To improve the service life of capacitor bank switch arcing contact used for ultra-high voltage system, the electrical endurance test under the environment of working condition was conducted. It was found that the CuW/CuCr arcing contact failed after about one thousand times of switch on and off test. The main factors influenc- ing the service life of the arcing contact were explored by analyzing the morphology, composition, microstructure and performance of the arcing contact before and after erosion. The results show that compared with conventional arcing contact materials, the failure of the arcing contact is caused not only by arc erosion, but also by mechanical wear and extrusion deformation. It is concluded that co-improvement of arcing erosion resistance, mechanical wear resistance and anti-extrusion deformation ability is important for producing the electric contact materials with long service time.