电感分断电弧放电机理及建模研究

发布时间：2018-11-17 17:43

【摘要】：随着电力电子技术的不断发展,对电气设备工作安全性和可靠性的要求越来越高。在许多电气设备中,电感发挥着重要的作用,但同时其开断有可能产生电弧放电现象,如果设备在含有易燃易爆气体的危险环境中使用,电弧放电就有可能会引燃气体,进而带来一系列的危害,因此通过对电感分断时电弧放电的理论研究得到其微观过程,对指导其本质安全具有重要的实际意义。而目前绝大多数研究都是在高压大电流的基础上进行的,并不能在本质上了解电弧放电原理,对于小电压、电流的电感分断电弧放电研究甚少,本文就以此为核心进行研究。根据电感分断电弧放电的爆炸性实验研究,我们得到了电弧放电时间极短,电压变化很快,而电流在放电过程中逐渐减小的特性。结合放电的普遍过程和粒子碰撞分析,提出电感分断电弧放电是由阴极发射电子和电子运动碰撞产生,此外金属融化产生的金属蒸汽加快了气体电离。建立了PIC-MCC模型,对电子发射、非碰撞运动和粒子碰撞进行了研究。运用动力学方程计算了带电粒子的位置与速度。依据一定的权重化方法,将带电粒子的电荷量累加到相应的网格点上,通过解泊松方程得到了带电粒子的电势和电场分布。利用软件进行仿真,得出了外电压和极间距对电弧放电的影响。结合电感分断电弧放电的宏观理论研究,对所建立的仿真系统进行验证,结果说明所建立系统的可行性,以及微观机理分析的正确性。
[Abstract]:With the development of power electronic technology, the requirement of safety and reliability of electrical equipment is more and more high. In many electrical equipment, inductance plays an important role, but at the same time its breaking may produce arc discharge phenomenon. If the equipment is used in a dangerous environment containing flammable and explosive gas, arc discharge may ignite the gas. Therefore, the microscopic process of arc discharge is obtained through the theoretical study of arc discharge when the inductor is broken, which is of great practical significance for guiding its essential safety. At present, most of the researches are based on high voltage and high current, so the principle of arc discharge can not be understood in essence. For small voltage and current, the research on arc discharge by inductor breaking is very few. According to the experimental study of the arc discharge with inductance breaking, we have obtained the characteristics of the arc discharge time is very short, the voltage changes rapidly, and the current decreases gradually during the discharge process. Combined with the general process of discharge and particle collision analysis, it is proposed that the discharge of inductively broken arc is caused by the collision of electrons emitted by the cathode and the motion of electrons. In addition, the metal vapor produced by metal melting accelerates the gas ionization. PIC-MCC model is established to study electron emission, non-collision motion and particle collision. The position and velocity of charged particles are calculated by using kinetic equation. According to a certain weighting method, the charge amount of charged particle is accumulated to the corresponding grid point, and the potential and electric field distribution of charged particle are obtained by unpoisson equation. The effects of external voltage and electrode spacing on arc discharge are obtained by software simulation. Combined with the macroscopic theory research of the arc discharge, the simulation system is verified. The results show the feasibility of the system and the correctness of the microscopic mechanism analysis.
【学位授予单位】：西安科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM501.2

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