接触电阻是表征电触点材料质量与可靠性的重要参数,本研究以可编程逻辑控制器(PLC)和单片机(MCU)为核心对电动滑台三维方向进行精准控制,并采用闭环系统精准控制接触压力,同时通过设计电压、电流信号调理与放大电路实现了接触电阻的自动连续测量。系统位移定位精度0.1μm,压力控制精度50 mg,接触电阻分辨率0.1 mΩ。最后应用测量系统完成了典型铆钉触点材料不同电流条件下接触电阻与接触压力间滞回特性的测量与分析。
Contact resistance is critical for quality and reliability of contact materials. The system, which applying MCU and PLC as the core to control the direction of three degrees of the motor-driven slide precisely, using the closed-loop system accurately control the contact force, and including the voltage, current signal modulation and amplification circuit, was designed in this paper in order to achieve the automatic continuous measuring and the analysis of contact resistance. The positioning accuracy of the system is 0.1 ~trn. The control precision of the force is 50 mg. The resolution of contact resistance is 0.1 mr. The hysteretic characteristics between contact resistance and contact force of typical composite contact material were measured with different excited current.