Research And Design Of Wavelet Transform Electromagnetic Interference Testing System Based O

With the current high-tech advances, the use of various types of electrical equipmentincreased significantly, that resulting in a large number of useful or useless electromagneticenergy and creating a complex and harsh electromagnetic environment, which would affectthe normal operation of the device and system. How to test and suppress these interferenceusing the effective methods or means has become a problem of electromagnetic compatibilitytesting, that aerospace, military-industrial complex, power electronics, communications,biotechnology, medical and other various industries paying attention closely and studyingstrongly. Based on the research of changing ideas, programs, technology and equipment of theoriginal test, this paper introduced the developing of a Conductive EMI measurement andsuppression systems, according to the cross-use of current multi-disciplinary andcomputerized, networked, automated testing technology. It will improve the performance ofelectronic equipment in electromagnetic noise environment.Wavelet denoising are satisfactory and have the advantage of good time-frequencyobservations. Using wavelet denoising program compiled by Matlab can easily work with VBhost computer in joint development and be very efficient and quick to complete suppressionof noise. So based on the applying of wavelet transform algorithm in the field of EMIprocessing, this paper proposed a research and design solution of EMI testing system basedon Wavelet Transform. Its funcion included conductive noise testing, noise sampling andtransforming, and analyzing, suppressing of the measurement results.Then, to improve the reliability of the interference signal testing methods, the sytem teststhe conductive EMI and its modal components combing the LISN with the noise separationtechnology.It controls noise sampling and digitized with FPGA and transfers the commandsand data with the high-speed LVDS interfaces. The design can not only save, call and modifyeffectively the results, but also promote the practical application of interference test system.Finally, a unit testing has been done with the above method of testing and Suppressingnoise. Test results fully validated that the interference testing and suppression system meetsEMC standards. And according to the final conclusion, this paper proposed a series ofimprovement measures to improve the performance of the designed system.