逆变电阻点焊电源焊接电流与电压的测量技术

焊接电流与电压的准确测量对精密控制逆变电阻点焊电源和保证焊接质量至关重要．文中在分析各种大电流测量方法的基础上，采用罗氏线圈外积分测量方式对逆变电阻点焊的焊接直流大电流进行测量．对实测结果的分析和基于Matlab的建模仿真表明，该测量方式可以准确地获得焊接直流大电流信号．文中还分析了不同电流设定和各种负载条件下的焊接电流与电压的实测波形，结果表明焊接电流是稍带脉动的直流，而焊接电压是明显脉动的，反映了电流与电压的动态信息．

Measurement of Welding Current and Voltage for Resistance Spot Welding Inverter

The accurate measurement of welding current and voltage is very important to the exact control of resistance spot welding inverter and welding quality. In this paper, the typical measuring methods for large currents are introduced, and the Rogoswki outer-integral measurement is adopted to obtain the large welding current of resistance spot welding inverter. This method is proved feasible by the analysis of experimental results and the model simulation via Matlab. Moreover, the welding current and voltage waveforms under different current setting and different welding load conditions are analyzed, with the results showing that the welding current is a kind of direct current with slight pulses, while the welding voltage is evidently pulsed. Thus, the dynamic information of the welding current and voltage is obtained.