Modeling And Prediction Of Conduction Electromagnetic Interference In PWM Inverter

As power electronic devices are widely used in various occasions,and the enforcement of EMC standards.EMC has become an important factor restricting the development of power electronics.And it is a research hotspot in recent years.This thesis mainly study conducted electromagnetic interference modeling and prediction of three-phase PWM inverter.Firstly,this thesis introduced the EMI testing process.LISN and attenuator are introduced,and the working principle are analyzed too.The working principle of spectrum analyzer is analyzed,showing that the measured results are influenced by the bandwidth of IF bandpass filter.Experiment is designed to verify the explanation.To obtain results that are consistent with the measured,a simulate spectrum analyzer algorithm is proposed in this thesis.The program is optimized to effectively reduce the algorithm time.Secondly,the characteristics of passive components are measured by impedance analyzer,we get its high-frequency equivalent models.Using the ANSYS Q3 D Extractor extraction method to get parameters that are difficult to measured.IGBT characteristic model is established in Simplorer.And time domain simulation is carried out in it.Experiments prove that the accuracy of the method.Finally,we change the interference source and propagation path by increasing the switching capacitor and the DC side common mode inductance.This thesis proves that the method still has better accuracy when the interference source and propagation path are changed,and can provide guidance for the design of inverter and EMI filter.