Design Of Electric Energy Metering Experimental Instrument Based On Multiwavelet Transform

With the rapid development of the economy,the non-linear load in the power grid increases,resulting in serious distortion of the power grid signal,the existing energy measurement methods and instruments can not accurately and reasonably measure the energy under the distortion signal conditions.To solve this problem,not only need a reasonable measurement method also need the corresponding hardware circuit and software algorithms.At present,there is no standard of energy measurement under the condition of distortion signal,and there is no standard measuring instrument for proofreading.In order to verify the correctness of the energy measurement method under the distortion signal condition,it is very necessary to design the distortion energy meter under the distortion signal.In this paper,the mathematical model of the typical distortion signal under the condition of distortion signal is established for the existing problems of electric energy measurement,and the power signal expression under the distortion signal condition is given.Based on the power flow analysis results,the method of reasonable measurement of electric energy under the condition of distortion signal is studied.On this basis,a multiwavelet energy measurement algorithm based on information entropy evaluation index is proposed.The ARM11 chip is chosen as the core processor,and the electric energy metering instrument is designed under the condition of distortion signal.In the aspect of hardware,the analog signal generator,the data acquisition module,the main control unit module and the man-machine interface interaction module are designed,and the design principle and realization method of each module are described respectively.In the software,the Linux system is embedded,the software design of the data acquisition module and the multiwavelet energy metering algorithm is completed,and the Qt graphical interface of the energy metering experiment instrument is designed.The electric energy metering for four kinds of typical distortion signals in power system carried out in the experimental apparatus,the experimental results verify the correctness and multi wavelet power real-time measurement index evaluation algorithm based on information entropy This provides some theoretical support and technical guidance for the study of the electric energy metering device under the condition of distorted signal.