Research On The Measurement System Of Crystalline Silicon Solar Cells Based On Machine Vision

In this paper,aiming at the issue of the printing offset of the solar cell,based on the research and analysis of the finger characteristics of the solar cell,a solution for visually measuring the width of the finger is put forward,and the measurement system of the crystalline silicon solar cell is developed.First of all,by analyzing the surface features of crystalline silicon solar cells,the key problems in visual measurement of the crystalline silicon solar cell are found out.At the same time,after analyzing the testing requirements of the system,the hardware design and software design of the measurement system of the crystalline silicon solar cell are carried out.In the hardware design,the suitable industrial camera,system illumination scheme and optical lens are selected according to the measurement precision of the crystalline silicon solar cells.In software design,the system uses C# language to develop modular software for the sake of efficient operation of the system.Then the filtering operator and the edge extraction operator of the crystalline silicon solar cell measurement system are discussed in detail.Through the experiment of image filtering and edge extraction,the appropriate image preprocessing algorithm is selected for the system.In addition,the camera lens distortion is analyzed theoretically,and the correcting error of the image distortion correction algorithm adopted by the system is analyzed by the calibration experiment.After analyzing the sub-pixel edge location algorithm in recent paper,an improved sub-pixel edge location algorithm,which combines interpolation and gray moments,is proposed in this paper for meeting the requirements of edge extraction of crystalline silicon cell measurement system.Through the simulation experiment,the precision experiment,the robust experiment and the efficiency experiment,the superiority of the algorithm in this paper is verified.Finally,the experimental verification of the crystalline silicon cell measurement system designed in this paper is implemented.Through the experiment of equal precision measurement,unequal precision measurement and system efficiency,measurement accuracy of the system is validated and the system can meet the requirements of real time detection and measurement accuracy of crystalline silicon solar cell.