| The traditional EMC standard test has some problems,such as strict test environment requirements,the test results can not reflect the EMC performance of the equipment in the normal working environment.The site test has become an important part of the EMC test because it can significantly improve the above problems.At present,many on-site test scenarios require the test time to be as short as possible,and the interconnection state between the tested equipment and other equipment to be changed as little as possible.In this thesis,the EMC on-site conducted sensitivity rapid detection technology is taken as the research object.In order to improve the site test efficiency,the current caliper injection is used as the signal injection mode.And the test items suitable for the fast detection technology are CS101,CS114,CS115 and CS116.Taking the display equipment as an example to analyze its sensitive characteristics,the thesis puts forward the strategy of preferred selection of sensitive frequency band,pre elimination of frequency band,and fast adjustment of signal source output,so as to achieve the purpose of fast detection of conduction sensitivity of display equipment,and finally designs and realizes the fast detection system of site test conduction sensitivity.First of all,the thesis analyzes the problems of long test time and many changes in the state of the tested equipment in the field environment,and then leads to the rapid detection technology of on-site conducted sensitivity.Through the analysis and comparison of the existing signal injection methods in sensitivity test,the current caliper injection method suitable for the application scenario of rapid detection technology is selected.Then,based on the analysis of the characteristics and contents of the commonly used conducted sensitivity test in GJB151B and the feasibility of the current caliper injection mode,the test items suitable for the rapid detection technology are CS101,CS114,CS115 and CS116.In order to realize the high efficiency of the fast detection technology,dynamic link library and multithreading technology are introduced.Then,the common display and control equipment is taken as a typical object for sensitivity analysis.Starting from the interference source,coupling way and sensitive parts,the common weak links such as power module,clock circuit and data transmission interface of display and control equipment are found.It is concluded that the sensitive frequency band of display and control equipment will be relatively concentrated,which provides a reference for the further research of rapid detection technology.Then,based on the analysis of the sensitive characteristics of the display and control equipment,this thesis studies the methods that can effectively realize the fast detection of the field sensitivity,including avoiding the untested frequency band caused by noise,optimizing the sensitive frequency band based on the correlation analysis method,and speeding up the signal output adjustment.This thesis focuses on the study of the strategy of selecting the sensitive frequency band first,designs the algorithm of selecting the sensitive frequency band first which is suitable for EMC sensitivity test by combining the Apriori algorithm in data mining,and verifies the algorithm through the CS114 and CS116 tests of LCD,which proves that the algorithm can effectively detect the sensitive frequency band of the device,and also improves the efficiency of conducting sensitivity test,so as to achieve the goal of rapid detection.Finally,combined with the research results of the sensitivity rapid detection technology,the design and development of the on-site conducted sensitivity rapid detection system is completed by using the automatic testing technology. |
