Design Of Electronic Control System For Ground Test Of Popular Science Load

In recent years,with the great progress of space technology,China’s exploration of outer space has become more frequent,especially in the lunar exploration project.Up to now,China has taken the lead in the world,such as the success of Chang’e IV,which makes China be the first soft landing country on the back of the moon.According to the three-step development strategy of "around,down and back",Chang’e IV has completed the second step of lunar exploration project,and the next step is to implement the third sampling return.Taking the popular science load control circuit carried by Chang’e IV as the research object,this thesis designs the ground electric control system of popular science load.Its main purpose is to find out the design defects of popular science load control circuit by using monitoring circuit,upper computer management software,fault diagnosis technology and reliability technology,so as to its improve stability and reliability.Finally,it provides a more perfect design scheme for the load control circuit of popular science.The work done in this thesis is summarized as follows:(1)Through the analysis of popular science load,the importance of improving the stability and reliability of popular science load control circuit is pointed out.Aiming at this problem,this thesis designs the ground electronic control system of the popular science load,and gives the main research contents and overall design scheme of this paper.At the same time,the key problems to be solved urgently in this thesis,the related technologies and technical indicators of the system are described.(2)The hardware design of the system is completed,including the popular science load control circuit and the monitoring circuit.The sensor data acquisition,temperature and humidity control,monitoring circuit data acquisition,data transmission and other aspects of the popular science load control circuit are analyzed emphatically.Under the condition of satisfying the basic functions,the reliability design of the popular load control circuit is carried out from many aspects to ensure that the circuit can work steadily and reliably under the conditions of low gravity,high temperature difference and strong radiation.(3)The software design of the system is designed,including the program design of load control circuit,monitoring circuit and PC management software.The flow chart of the important part of the system is given and analyzed in detail.Finally,aiming at the potential faults such as intermittent faults caused by virtual welding or interference,sensor drift faults caused by temperature,bias fault caused by misalignment of bias current or voltage,the feature extraction of test point signals is carried out by wavelet analysis,and the fault diagnosis of the system is realized based on the classification algorithm of support vector machine.(4)The system platform is built based on the design of load control circuit,monitoring circuit and PC management software,and testing the important circuit and reliability design of the system.The test results show that the design of the hardware and software of the system is reasonable,and can achieve the desired results.