Influence And Strategy Of Harmonics On Power Energy Measurement

This thesis introduces the construction and calculating principle of induction meter and electric watt-hour meter,discusses harmonic influence on the two kinds of meter. Against the exiting problem in the method to measure harmonic energy on the basis of FFT,which is hard to make an efficient,quick and accurate measurement of non-stationary signal and inter-harmonic signal.This thesis researches and comes up with a method to measure harmonic energy based on wave packets transform.This method directly takes advantage of the reconstructed coefficients of wave packets to calculate the power of frequency band,then the power is multiplied by sampling time,so the energy is acquired.The emulation experiment has verified the method can accurately calculate harmonic energy,especially can reselve the measuring energy problem of non-stationary signal and inter-harmonic signal.At last the thesis preliminarily designs a system to measure harmonic energy based on wave packets transform.The processing unit in the system may satisfy the running speed requirement of the algorithm.