EIS Data Processing Software Based On MFC

Impedance is the sum total of the hindering effects of all elements in the circuit on the current.AC impedance spectroscopy is a collection of impedance at different frequencies measured by an impedance test system.It is convenient to research by processing these data to coordinate drawing and required parameters.The impedance measurement instruments produced by different manufacturers have different measurement parameters and different file types.The existing impedance data processing software is poor in compatibility and cannot handle different data formats.In this essay,the software for impedance data processing Zpro which based on MFC with good versatility and good compatibility is designed.The software has four function modules,which are Data Reading and Saving,Image Displaying and Processing,Equivalent Circuit Analysis.Data Reading and Saving part is designed to read different data format and type.Extracting useful information and converting data by formula to facilitate data processing when necessary.Then save the data after processing.In Image Displaying and Processing part,measurement data are grouped into the software at first.It will draw the corresponding coordinates after the parameters of the Nyquist and Bode diagram are set.Measurement parameters and serial numbers will be displayed by selecting a data point through the keys.The unreasonable data points or data segments which can be judged as errors can be deleted manually.Dragging the mouse to select the data segment can enlarge the image.This operation is designed to display the data more clearly for data analysis.The Equivalent Circuit Analysis part can be divided into standard equivalent model and user-defined equivalent model.There are five kinds of commonly used models in standard equivalent model.Selecting the appropriate data segment and different kind of simple equivalent circuit at first,then the software can calculate the parameters of each component.The results will be taken as the initial value of the whole fitting.It will also examine the error between the fitting curve and the measured data.User-defined equivalent model is drawn by input Circuit Description Code.The initial value of each element is assigned to the equivalent circuit,and the simulation,fitting and error analysis are carried out.The contrast processing of multiple sets of data is beneficial to compare the changing trends of several curves.The fitting algorithm uses the least squaresfitting method of data,which include linear fitting and arc fitting.The interface of the software is to use MFC to write.The design of the menu bars,quick tools and dialog boxes make the software beautiful and simple.After the software is written,it is tested by importing impedance data.There are first order RC series circuit,first order RC parallel circuit and two order RC parallel circuits.The test results show that the error of the parameters of the device is less than 0.9% by the software Zpro.And the fitting curve coincides with the original curve.