Research On High Power 3D Integrated Three-Phase Common-Mode EMI Filter

The high electrification is the necessity of automobile technology progress under the growing demand of people,and it is also the development trend and research hotspot of automobile technology in a long period of time.Compared with the traditional internal combustion engine automobile,the rapid increase of electrical and electronic equipment makes many types of electrical electromagnetic equipment concentrated in the interior of the vehicle body.The vehicle control,communication and navigation equipment are connected by electrical equipments,constitute an extremely complex electromagnetic environment.The electromagnetic compatibility between various systems within the car,and between the car and the external environment is of great significance for the safe operation of the car and the normal work of other electronic devices in the external environment.The implantation of power electronic devices,while increasing the performance of the system,as a source of electromagnetic noise,complicates the electromagnetic compatibility problem at the entire systemic level.With the commercialization of high-power widebandgap semiconductor switching devices based on Ga N and Si C materials,the switching speed of power devices has been greatly increased and the switching frequency has been higher,which makes the electromagnetic interference problem more serious and the noise spectrum wider.Moreover,the scenario is becoming more and more serious due to the widespread application of wide band gap transistors.As disastrous results,the interference will lead to bearings wear out quickly and disturb the control or measure system.Applying passive EMI filters is the simplest and most effective EMI suppression method.Since the EMI filter is typically composed of bulky inductors and capacitors,it is large in size and small in power density,and these disadvantages are even more pronounced especially in high-power situations.At the same time,the parasitic parameters will frequently degrade the performance of EMI filters,and the handmade components,such as CM inductors,will worsen the situation.And in high-power occasions,the diameter of the cable is thicker and difficult to bypass.Therefore,it is necessary to establish the design concept and method of the new passive EMI filter under the development trend of power electronics technology.In order to effectively reduce the volume of EMI filter and improve its performance,this thesis presents a design method of high power 3D integrated three-phase common-mode EMI filter suitable for vehicle system and studies it.Integration is the development trend of power electronic system,3D printing technology in mechanical manufacturing has shown excellent performance,can be very easy to manufacture the complex mechanical parts of the cavity,and multi-nozzle technology can be more than a variety of materials to complete the final design,the rapid development of these rapid manufacturing technology,can provide good technical support for the production of electronic systems.Firstly,this thesis introduces the research background of the subject,including the present research situation and the purpose and significance of the topic.Secondly,this thesis analyzes the generation mechanism of the high frequency electromagnetic interference of the system,establishes the design index.Then puts forward the design scheme of the subject and the analysis of optimization.This thesis mainly introduces the structure and advantages of a high-power 3D integrated EMI filter.The EMI filter is integrated by planar commonmode inductor and planar capacitor.The planar structure is beneficial to make better use of space,thus increasing its power density.The interconnection process of 3D can easily realize the complex electromagnetic structure and greatly improve the inductance performance under the given volume.The 3D stacked planar core method can complement the performance of magnetic cores with different properties.So that the insertion loss in a very wide frequency band to maintain a high level.At the same time,the planar capacitor adopts the stamping conductor layer structure as the lead terminal.The connection mode has good conductivity,and can reduce the mechanical impact caused by vibration,reduce the equivalent series inductance of capacitance,widening the frequency band of insertion loss of the filter,and further improve the performance of EMI filter.Finally,the feasibility of the design is verified by simulation and prototype.The 3D integrated EMI filter designed by this study,compared with the traditional highpower EMI filters,the volume decreases,the power density increases,the insertion loss performance improves,the frequency band of high insertion loss widens,and the industrial production is easy to be realized,the consistency of product parameters are good,and the parasitic parameters are controllable.