Research Of The Sun Tracker Control System For Balloon Flight Solar Cell Calibration

In recent decades, multi-junction solar cells have been made great progress and arewidely used in the field of space. So they are ideal energy for a variety of spacecraft. Inthe design of solar energy systems used in aviation systems, the solar cell performanceparameters under the standard sunlight are needed to obtain. Light battery calibration onthe ground, cannot adequately reflect the true performance of solar cells, so Earth’s outeratmosphere AM0calibration tests are needed to carry out on the solar cells. This paperanalyzes and summarizes the domestic and international high-altitude solar cell calibrationand tracking technologies. According to the requirements of high-altitude balloons solarcells calibration testing, an in-depth study is carried out on the solar tracking controlsystem.Firstly, the status about high-altitude solar cells calibration and solar tracking controlsystem on the stage was introduced. Based on the analysis of the architecture and featuresof the solar cell calibration test system, the mechanical structure of the solar tracking wasdesigned. At the same time, solar tracking control system based on STM32was designed,and the design of main control board hardware, sunlight tracking sensor selection, andother aspects of mechanical transmission were conducted to optimize and improve theperformance of the tracker.Secondly, the solar tracking control system software has been written, which includesmain control system initialization subroutine, sun sensor data acquisition and processingsubroutine, stepper motor driver subroutines and so on. Taking the special circumstancesand the high altitude balloon campaign into account, effective programs were put forwardwhich could ensure the accuracy and reliability of the sun-tracking. At the same time, thetracking control algorithm was optimized to improve the quickness and stability of thesystem.Finally, to ensure the stability and reliability of the high-altitude sun tracking controlsystem, some experiment were done on the ground, such as the light sensor testing,depending on the date of the motion trajectory tracking algorithm debugging, low temperature vacuum environment evaluation test and outdoor car mobile trackingsimulation experiments. The balloon flight solar cell AM0calibration experiment wasconducted successfully. By analyzing the test data, the effectiveness of the tracking systemwas verified.