焊机输入电量测量方法的探讨

Research on measuring method for input power of welding machine

为了解决在非正弦输入电流的条件下对焊机输入电流、输入功率、功率因数等各种电量的测量问题,讨论了周期交流电流电路、正弦周期电流电路和非正弦周期电流电路中各种电量的数学关系。分析和探讨常规仪表测量非正弦周期电量所存在的问题。试验结果表明,对于非正弦周期电量应采用基于谐波分析的数字化智能仪表进行测量,用常规仪表测量将产生一定的误差。

In order to solve the problems in measuring welder input current,input power and power factor under the condition of non-sinusoidal input current,mathematical relations in a variety of electricity are presented and discussed for periodic alternating current circuits,sinusoidal periodic current circuit and non-sinusoidal periodic current circuit.The problems in measuring non-sinusoidal periodic electricity by conventional meter are analyzed.The results show that non-sinusoidal periodic power should be measured by digital intelligent instrumentation based on harmonic analysis,and measuring with conventional instrumentation will have some error.