Author: Bao, Yude
Title: Study of analysis for electromagnetic interference in DC/DC converter system of electric vehicle
Advisors: Lam, Kwok Ho (EE)
Degree: M.Sc.
Year: 2017
Subject: Hong Kong Polytechnic University -- Dissertations
Electromagnetic interference
Electric vehicles
Department: Faculty of Engineering
Pages: 113 pages : color illustrations
Language: English
Abstract: The DC/DC converter system is the main source of electromagnetic interference (EMI) in the electric vehicle, because the electromagnetic emission from the system has the characteristics of high-energy and wide-bandwidth. Consequently, the EMI of DC/DC converter system becomes one of the biggest obstacles for meeting the EMC standard. This study focuses on the analysis and suppression of conducted EMI of DC/DC converter system, and the main contents are as follows: 1. To analyze the EMI mechanism and conducted path in DC/DC converter system according to the working principle of the system. The software Saber has been used to model the full bridge DC/DC circuit to analyze the principal factors of common mode interference transmission. 2. Based on component parameters provided from manufactures, a method has been studied to build a high-frequency equivalent circuit model of every component in the DC/DC converter system, such as MOSFET, diode and storage battery. Based on finite element method, Pexprt software has been combined with Maxwell 2D software to establish a high-frequency model of magnetic components (transformers, inductance). 3. To build a conducted EMI bench of the DC/DC converter system, a high-frequency circuit model has been established according to the experimental physical parameters of each component, and an experimental bench model has been established in Saber software. In 0.15- 108 MHz range, the simulation predicted the common-mode (CM) interference on the line impedance stabilization Network (LISN) and it was compared with the experimental results. The validity and feasibility of the method that could predict the conducted EMI of the DC/DC converter system in this study has been verified by simulation. At the same time, the magnetic components (transformers, inductance) in the model, switching components (MOSFET, diode), LISN and battery-accuracies have been verified accurately. Moreover, the parasitic parameters of switching components' have been confirmed. 4. After analyzing the reason why EMI formed, this study finds some ways to suppress the EMI in DC/DC converter from the three basic elements of EMI, which is the source, coupling path and sensitive equipment. This study uses the soft-switching technique and simulate in Saber, then design an EMI filter and use saber to confirm the effect. After that we introduce a kind of metal material for shielding. 5. Lastly, this study designs a EMI reducer system and make a product. And we also make measurement to confirm the system's effectiveness. Besides, some other ways are also introduced.
Rights: All rights reserved
Access: restricted access

Files in This Item:
File Description SizeFormat 
991021953150403411.pdfFor All Users (off-campus access for PolyU Staff & Students only)2.84 MBAdobe PDFView/Open


Copyright Undertaking

As a bona fide Library user, I declare that:

  1. I will abide by the rules and legal ordinances governing copyright regarding the use of the Database.
  2. I will use the Database for the purpose of my research or private study only and not for circulation or further reproduction or any other purpose.
  3. I agree to indemnify and hold the University harmless from and against any loss, damage, cost, liability or expenses arising from copyright infringement or unauthorized usage.

By downloading any item(s) listed above, you acknowledge that you have read and understood the copyright undertaking as stated above, and agree to be bound by all of its terms.

Show full item record

Please use this identifier to cite or link to this item: https://theses.lib.polyu.edu.hk/handle/200/9013