Research And Application Of New Technology Methods For Conductive Electromagnetic Compatibility

In recent years,with the continuous improvement of power electronics technology and the continuous development of wireless communication,the electromagnetic interference in electronic equipment has become increasingly prominent, seriously affect the normal operation of electronic equipment, so the diagnosis of electromagnetic interference is becoming important research content, which designed effective suppression measures, the paper suppress electromagnetic interference noise by the means of power transmission line plus magnetic ring, PCB board to add copper foil and other shielding measures. To this end, this paper carried out "conductive electromagnetic compatibility new technology research and application".First of all, this paper makes research in electrical fast transient. The performance of the EFT is a kind of high frequency and high energy source of interference,and the frequency of 5KHz goes through the power line interference of internal conduction into the device. When the normal frequency of the electronic equipment is 50Hz and the pulse group of high frequency noise is 5kHz, the transmission impedance of the transmission line can not be ignored when the EFT is tested. The work equipment transfer impedance sometimes is mismatched , so EFT interference leads to noise interference of multiple reflections on the transmission line and gets the impedance information of inductance and capacitance. This paper solves the problem of optimization of extraction parameters of nonlinear equivalent impedance by modeling. Based on matching the specified pass band and stop band and ideal conditions general impedance to design new EFT filter, and the EFT filter design examples can be verified the validity of the new filter.Secondly,the paper carried out the study on the identification method of conducted EMI noise source and on the extraction method of internal impedance of noise source.The chapter analyzes the basic principle of the classic method of the kernel principal component analysis (KPCA), and summer up the specific steps of the algorithm to identify and isolate the conducted EMI noise in the equipment with kernel principal component analysis (KPCA).It restrains the noise that caused by excessive electronic products.. On the basis of impedance extraction in the transmission noise source, the S parameter method is used to extract the noise source impedance. The paper carry out the theoretical derivation and passive component impedance extraction experiments. And the experimental results show the accuracy and effectiveness performance of the impedance extraction method.Finally,by combining with the electronic systems of electronic equipment,this paper analyzes the problems of the excessive electromagnetic noise and designs a responding ideal EMI noise suppression scheme. The paper verifies the validity and practicability of the method,which provides theoretical and practical basis for the engineering application of electromagnetic noise suppression in the future.