Radiant Discharge Development Model for Polluted Surface Along Short Plate Under DC Voltage

为了能够深入了解污秽沿面放电的机制,将电弧等效为带电粒子流,基于流体力学知识来研究电弧的发展规律。通过电弧受力分析和局部电弧头部流注长度随温度变化的计算,阐述电弧的发展和闪络形成过程。根据能量守恒定律,将电弧中带电粒子流的集体运动等效为一个可以产生辐射的阻抗,由此建立了电弧发展的电路方程模型,并且计算了污闪的临界电压、临界电流和临界电弧长度,然后将其与早期模型计算结果和试验值进行了比较。研究表明,所提出的模型计算结果与试验结果保持一致,并在预测临界闪络条件准确度上优于早期计算模型。通过引入电弧辐射常数解释了模型中所取实验常数的物理意义,深化了电弧特性的物理内涵。

Discharge along the polluted surface of an insulator is always a major problem in power transmission systems, and it remains a hot subject in high voltage insulation field and receives much concern. Many methods are developed to deal with the polluted flashover of an insulator, and great progress has been achieved in engineering application. Although the basis of selecting the parameters in early models has been studied and the calculation model has been optimized, the widespread power blackout caused by flashover still takes place sometimes.