摘要
脉冲电压老炼是提高真空电极间隙击穿特性的有效方法。该文采用64/700μs冲击电压对纯铜球电极进行脉冲电压老炼试验,利用X射线光子能谱表面分析、阴极表面粗糙度及扫描电子显微镜测量,结合Fowler-Nordheim理论,分析诊断了脉冲电压老炼过程中真空击穿波形的击穿机制,并揭示真空击穿机制的演化机理。结果表明:阴极表面X射线能谱Cu峰变化对比,表面粗糙度及其突起结构和微观金属微粒分别支撑验证了老炼过程中击穿波形包含脉冲电流诱发真空击穿,场致发射诱发真空击穿和微粒诱发真空击穿3种击穿机制。脉冲电压老炼过程中存在不同真空击穿机制的演化过程,具体为:老炼起始阶段的击穿机制主要为脉冲电流诱发真空击穿和微粒诱发真空击穿;随后老炼过程由微粒诱发真空击穿主导,脉冲电流诱发真空击穿消失,场致发射诱发真空击穿逐渐增多;最终,老炼饱和阶段由场致发射诱发真空击穿与微粒诱发真空击穿共同主导。该试验结果为从击穿机制演化机理角度提升真空电极间隙击穿特性提供重要理论参考。
Impulse voltage conditioning is an effective method to improve the breakdown characteristics of the vacuum electrode gap.In this paper,spherical pure copper electrodes were subjected to impulse voltage conditioning using 64/700μs impulse voltage.X-ray photoelectron spectroscopy was adopted to analyze the surface of the cathode,and the surface roughness and scanning electron microscope images of cathode were measured.Combined with the Fowler-Nordheim theory,this paper analyzed and diagnosed the breakdown mechanisms of vacuum breakdown waveforms in the process of impulse voltage conditioning,and revealed the evolution law of vacuum breakdown mechanisms.The results show that the comparison of Cu peak changes in the X-ray energy spectrum of the cathode surface,the surface roughness and its protrusion structure and the microscopic metal particles support and verify that the breakdown waveforms during the burn-in process include three breakdown mechanisms:pulse current-induced breakdown,field emission-induced breakdown and particle-induced breakdown,respectively.In addition,the evolution process of different vacuum breakdown mechanisms in the impulse voltage burn-in is as follows:pulsed current-induced breakdown and particle-induced breakdown dominate the beginning of the conditioning.Then,particle-induced breakdown dominates the burn-in,pulse current-induced breakdown disappears and the times of field-emission induced breakdown gradually increase.Finally,particle-induced breakdown and field emission-induced breakdown dominate the saturation stage of the burn-in,The experimental results provide a significant theoretical reference for the improvement of breakdown characteristics in vacuum electrode gap from the perspective of the evolution law of the breakdown mechanisms.
作者
李世民
江希茜
李镇廷
杜昭启
杨威
张潮海
LI Shimin;JIANG Xixi;LI Zhenting;DU Zhaoqi;YANG Wei;ZHANG Chaohai(College of Automation Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 211106,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2023年第11期4790-4797,共8页
High Voltage Engineering
基金
国家自然科学基金(52207162)
江苏省自然科学基金(BK20210307)
江西省自然科学基金(20202BABL214035)。
关键词
真空断路器
脉冲电压老炼
击穿机制
电压电流波形
电极表面物理特征
演化机理
vacuum interrupter
impulse voltage conditioning
breakdown mechanism
voltage and current waveforms
physical characteristics of electrode surface
evolution law
