Research On Key Technologies Of High Altitude Solar Cell Performance Test And Calibration System

The solar cell is an important part of the energy of the spacecraft,and the accurate calibration of the solar cell can provide data reference for the assembly of solar panels.The Terrestrial solar simulator may bring in error,and can't accurately reflect the performance of solar cell under conditions of high altitude,which may have a bad impact on the application of solar cell in space.So it has a very important significance to research calibration technology of the solar cell under conditions of high altitude.The technology of High altitude solar cell calibration originated in the United States.After a long period of theoretical and experimental research,the scheme gradually matured and becomes an important part of the calibration standard of the international space solar cells.China is still in the initial stage,only two exploratory solar cell short-circuit current tests were carried out.In view of the high altitude solar cell testing technology is still not perfect,and lack of theoretical research,this paper focuses on the key technologies of high altitude solar cell testing and calibration methods.Firstly,the paper studies the power generation mechanism and electrical characteristics of the solar cell.According to the test environment,the key technologies and methods of the short circuit current test and I-V characteristics on solar cell in high-altitude environment is introduced.A short circuit current calibration system based on sampling resistance and a I-V characteristic test system based on programmable electronic load for solar cell are designed,which can run the test on the solar cell automatically.Secondly,according to the measurement error in the experimental data,the curve fitting algorithm is studied to get more accurate I-V curve data.Based on the analysis of the equivalent mathematical model of solar cell,a method for fitting the I-V curve of solar cell based on chaotic genetic algorithm is proposed.In view of the solar cell I-V characteristics data,the algorithm is run for curve fitting,which gets the value of the parameters of the equivalent mathematical model.The comparison between the results of the chaotic genetic algorithm and other algorithms shows that the chaotic genetic algorithm can get smaller curve fitting error.Finally,the ground test is carried out on load platform and the solar cell measure system.The performance of the system is studied by simulating the high altitude environment in the low temperature and low pressure chamber.The performance of the solar cell short circuit current calibration subsystem and the I-V subsystem of the solar cell is tested in the ground sunlight.The analysis of the short circuit current of the solar cell shows that the system works well,and there is no obvious gross error.The I-V curve of solar cell is analyzed,and the curve is fitted to the data.Through these tests,the system has the ability to put high altitude experiment into effect.