短间隙真空开关电弧特性的量化分析及其调控理论研究

Research on the regulation and control theory of VSA（vacuum switching arc） is one of the great subjects in the field of vacuum circuit breakers, further quantitative study and finding an effective regulation and control means is an available way to solve this issue.This subject takes VSA in short-gap as the investigative object,the geometric features of the vacuum arc and macro-particle are analyzed; the migration law of cathode spot, anode spot，macro-particle and plasma are studied; a MHD model of VSA plasma is built and the boundary and initial condition are analyzed; the combustion mechanism of VSA in short-gap is probed and analyzed theoretically in this subject in detail.Through simulation and experiments，a quantization and diagnosis model of VSA influenced by many complicated factors such as vacuum gap, electrical contact，electric field and magnetic field is built to reveal the characteristic of VSA in quantitative aspect, mastering inherent mechanism and finding the effective regulation and control means.The aim of this subject is to diagnose the characteristics of VSA in short-gap, holding the essential characteristic of combustion mechanism,especially the researches on multiple repeated breakdowns and multiple repeated reignition,putting forward effective means of regulation;making further enrichment and development of theory of VSA.All these lay down a soild theoretical base and experimental technology foundation for the researches on solving the regulation and controlling of VSA and developing new type vacuum circuit breakers.

真空开关电弧调控理论研究是真空开关研究领域研究热点之一，深入研究真空开关电弧特性并使其量化以找到有效调控手段是解决该课题的有效途径。本项目以短间隙真空开关电弧为研究对象，分析其电弧形态和宏观粒子的几何细节特征，研究阴极斑点、阳极斑点、宏观粒子及等离子体的迁移规律，建立短间隙真空开关电弧等离子体MHD模型及分析其边界与初始条件，对短间隙真空电弧燃烧机理进行全面理论分析与实验研究。通过实验与仿真研究，建立真空间隙、电极触头、电场及磁场条件等多因素复杂影响的短间隙真空开关电弧的量化诊断模型,实现其特性的精确量化描述。本项目旨在实现短间隙真空开关电弧特性的量化诊断，掌握其内在燃烧机理，特别是多次重击穿和多次重燃机理的研究，以找到有效的电弧调控手段，进一步丰富和发展真空电弧理论，为解决真空开关电弧调控难题和研制出新型真空灭弧室奠定理论和实验技术基础。

真空开关电弧调控理论研究是真空开关研究领域研究热点之一，深入研究真空开关电弧特性并使其量化以找到有效调控手段是解决该课题的有效途径。本项目以短间隙真空开关电弧为研究对象，通过可拆卸真空灭弧室实验平台和图像处理与识别技术实现了电弧在燃烧过程中的电弧形态几何特征(轴向半径、面积和周长等)变化过程精确量化描述;同时为了实现研究操动机构运动参数对电弧形态特征的影响, 为满足高精度分析的需求，提出运用数字图像处理技术从真空开关运动序列图像中精确跟踪触头位置，进而计算触头运动速度的检测方法. 运用Harris角点检测算法提取序列图像中触头角点，从而实现了动触头位置的亚像素级精度跟踪亚像素角点检测技术可实现动触头位置跟踪及其分闸速度计算，且相对误差≤4.7%，最高精度可达0.34%。该方法能够实现真空开关分闸速度的高精度检测，为后续分析分闸速度与电弧形态的关系奠定了基础.利用电弧数值仿真技术，计算得到了扩散阶段大电流超音速电弧和亚音速电弧的光强大小及其变化规律；建立短间隙真空开关电弧等离子体MHD模型及分析其边界与初始条件，计算了短间隙中超音速电弧和亚音速电弧的阳极表面能流密度参数，并进一步讨论了电弧电流、触头开距和纵磁场（AMF）等燃弧参数变化对该参数影响。通过实验与仿真研究，建立了真空间隙、电极触头、电场及磁场条件等多因素复杂影响的短间隙真空开关电弧的量化诊断模型,本项目旨在实现短间隙真空开关电弧特性的量化诊断，掌握其内在燃烧机理，特别是多次重击穿和多次重燃机理的研究，以找到有效的电弧调控手段，进一步丰富和发展真空电弧理论，为解决真空开关电弧调控难题和研制出新型真空灭弧室奠定理论和实验技术基础。