The electric characteristics of the charging and discharging devices of the rapidly developing electric vehicle industry are nonlinear and impact-like.The traditional watt-hour meter can hardly meet the requirements of dynamically distorted loads accurate measurement，a drawback aggravated also by a lack of corresponding verification source method.So the improved ip -iqalgorithm for specific integer harmonic wave，fundamental wave and harmonic voltage to process real-time frequency detection is proposed.The algorithms based on real-time fast Fourier transform（FFT）and quasi-synchronous sampling linear interpolation and nonlinear amplitude compensation are put forward.The broad range of impact loads measurement technique based on variable amplifying is proposed.The related devices are also developed to effectively solve the source tracing of the dynamically distorted load metering and detection of direct voltage during voltage discharging.The application effect proves the suggested electricity measurement method and devices can meet the demand of tracing the source of dynamically distorted load metering.