Analysis And Application Of High Frequency Characteristics Of Inductance Devices Based On Conducted EMI Suppression

At present,the high du / dt and di / dt on semiconductor switching devices that are prone to generate strong electromagnetic interference emissions have seriously affected the development of the electronics industry.It is very effective to use electromagnetic interference(EMI)filters to suppress conducted EMI noise in power electronic equipment method.According to relevant literature,the behavior of inductive components at high frequencies often determines the effectiveness of EMI filters in suppressing conducted noise.Therefore,the research can be carried out in depth from the high-frequency equivalent circuit of the inductor,and the high-frequency characteristics and modeling methods of the magnetic inductor are studied.Common mode inductors(common mode choke coils)and differential mode inductors are installed in EMI filters on a large scale.On this basis,the principle of conducted electromagnetic interference and its suppression methods are analyzed.In order to explore the application of high-frequency characteristics of inductance in conducted noise suppression,the design ideas of conducted EMI filters are studied from the aspects of conducted noise mechanism,noise diagnosis method and noise suppression mechanism.In the study of the high-frequency characteristics of inductors,several methods for modeling the non-ideal frequency characteristics of inductors in domestic and foreign literatures are compared,and the high-frequency characteristics of the inductors are combined with the complex permeability(CMP)theory of the inductor and its working principle.mold.Moreover,in the study of extracting the optimal parameters in modeling,a hardware experiment platform for inductance element impedance parameter extraction and a software platform for complex permeability equivalent parameter optimization algorithm are built.At the same time,the specific steps and implementation process of extracting equivalent parameters of impedance by vector network analysis instrument(VNA)are analyzed.On this basis,the optimal parameter value is successfully extracted by using differential optimization method and impedance expression.On the other hand,the optimization principle of the Mcquart method and the genetic algorithm in the least square method is analyzed,and the advantages and disadvantages of the two algorithms in the process of fitting optimization are compared by combining the inductive complex permeability modeling Optimization of equivalent parameters for inductive complex permeability modeling.At the same time,the specific application of inductive devices in suppressing conducted EMI was analyzed.The source of the conduction noise of the switching power supply is explored and its conduction EMI path and Boost PFC equivalent circuit are analyzed and modeled.The actual application simulation of the inductive device in the switching power supply Boost PFC circuit was realized on Ansys software,and its suppression mechanism was summarized.At the same time,by analyzing and rectifying the specific cases of inductive devices in suppressing the conducted EMI of medical electronic equipment,each device can meet the requirements of the electromagnetic compatibility(EMC)standard,and it can better explain that inductive components are suppressing the EMI of power electronic devices The actual effectiveness of the interference.