基于电接触元件暂态热路建模的接触电阻测量研究.pdf

第42 卷 第15 期 电力系统保护与控制 Vol.42 No.15 2014 年8 月1 日 Power System Protection and Control Aug. 1, 2014 基于电接触元件暂态热路建模的接触电阻测量研究 张青山，段建东，叶 兵，樊 华，张宏光 (西安理工大学电气系，陕西 西安 710048) 摘要：目前，接触电阻的检测主要是电压电流法或电桥法，其不足是仅适于离线应用。提出了一种在线式的接触电阻间接测 量新方法。首先在建立电接触元件的理论物理模型和径向暂态热路分析模型的基础上，推导出热路响应方程；然后再在建立 元件轴向热传导数值分析模型的基础上，最终推导出计及温度和电流的接触电阻曲线关系，提出通过曲线的时间常数计算电 接触元件的接触电阻。大量的理论分析、计算与有限元分析ANSYS仿真表明，所研究的测量方法可以准确求取接触电阻的 值，为电气设备的在线监测和热缺陷分析提供了理论依据。 关键词：电接触；热路建模；温度传导；接触电阻 Research of measuring contact resistance based on the electrical contact transient thermal circuit model ZHANG Qing-shan, DUAN Jian-dong, YE Bing, FAN Hua, ZHANG Hong-guang (Xian University of Technology, Xi’an 710048, China) Abstract: At present the main method of measuring contact resistance is bridge method or detecting voltage/current, the shortage is only suitable for offline applications. A new method of online measuring contact resistance based on the transient thermal circuit model is raised. Firstly the theoretical physical model and the radial transient thermal circuit model of electric contact components are established, the thermal circuit response equation is concluded based on theory analysis. Then the axial heat transfer numerical analysis model is established. Finally the contact resistance model considering temperature and current is derived from the theory analysis, a method of measuring contact resistance by using the curve of thermal time constant is raised. A lot of theoretical analysis/calculation and finite element analysis of ANSYS simulation results show that the method can accurately obtain the value of the cont