Graduation Design (Thesis) of Wuhan University of Technology

Overall Design of a Miniature Pure Electric Vehicle

School: International Education College

Specialty amp; Class: Automotive Engineering gj1304

Student name: 罗景

Tutor: 喻厚宇

Statement of Originality

I solemnly declare that the thesis I submit is a piece of writing I completed independently based on my own research under the guidance of my supervisor. Except for the quotations, this paper does not include any writings published or completed by other individuals or groups. I am fully aware that the legal consequences of this statement are borne by me.

Signature of the author:

Date:

Copyright Letter of Authorization to The Dissertation

The author of this dissertation fully understands provisions stipulated by this school on keeping and using dissertations. The author agrees that the school can reserve and send photocopies and electronic versions of this thesis to relevant departments or institutions managing dissertations. This thesis can be read and borrowed. I hereby authorize excellent provincial institutions appraising bachelor dissertations to incorporate all or any part of this dissertation into relevant databases for retrieval, as well as to preserve and compile this dissertation by photocopying, scanning or reprinting it in a reduced format.

This dissertation is: 1. Confidential until(year) and then this authorization letter will apply. 囗

2. Non-confidential. 囗

(Please tick "√" the corresponding box above)

Signature of the author:

Date

Signature of the tutor:

Date

Abstract

Nowadays pure electric vehicle is more and more popular for the problem of environment pollution and worldwide energy shortage. With the development of urbanization, urban traffic congestion has affected many cities in China. Development of miniature pure electric vehicle can not only alleviate environmental problems, especially air pollution, but also make positive effort on improving urban traffic condition.

Based on Dongfeng Fengshen E30L, this paper has done the overall design of a miniature pure electric vehicle. It includes the selection of main assembly components, design of the drive system, matching the power storage system and vehicle overall layout. Firstly it has made the selection of main assembly components and main parameters of the vehicle. Secondly it has designed the drive system including traction motor design and selection, transmission system design and check of dynamic requirements. It has put forward a new method to improve the dynamic performance. By planetary gear mechanism, the designed vehicle can shift gears to overcome gradient resistance. Besides, planetary gear mechanism also makes positive effort on acceleration condition and energy control. Thirdly, this paper has done the design of energy storage system and checks the drive range of designed vehicle. Based on ADVISOR, its drive range performance was simulated and analysed. It has check the drive range in three road conditions of CYC_ECE ,CYC_CONSTANT45 and CYC_EUDC_LOW. The results showed that efficiency of the traction motor plays a significant role in drive range. Finally, it has completed vehicle body design and body layout. It also concluded chassis layout and motion correction. Most information in this part is shown in engineering drawings.

The paper has finished the overall design for required performance and it has put up a new idea on power train for miniature pure electric vehicle. It may provide reference on miniature pure electric vehicle overall design

Key words: pure electric vehicle; overall design; power train; driving range

Content

Chapter 1 Introduction 1

1.1 Research Purpose and Significance 1

1.2Domestic Development Status 1

1.3Worldwide Development Status 2

1.4 The Main Content of This Study 2

Chapter 2 Determining the Overall Parameters and Selecting Main Assembly Components 4

2.1 Determining the Dimensions of Miniature Pure Electric Vehicle 4

2.2 Determining the Mass Parameters of Miniature Pure Electric Vehicle 5

2.3 Determining Main Performance Parameters of Miniature Pure Electric Vehicle 5

2.4 Selecting Traction Motor of the Miniature Pure Electric Vehicle 6

2.5 Selecting Transmission System of the Miniature Pure Electric Vehicle 6

2. 6 Selecting Power Storage System of Miniature Pure Electric Vehicle 7

2. 7 Selecting Suspension System of Miniature Pure Electric Vehicle 7

2. 8 Selecting Steering System of Miniature Pure Electric Vehicle 8

2. 9 Selecting Braking System of Miniature Pure Electric Vehicle 8

2. 10 Selecting Vehicle Body and Tire Type of Miniature Pure Electric Vehicle 9

Chapter 3 Design of Drive System of the Miniature Pure Electric Vehicle 10

3. 1 Selection of Traction Motor 10

3.1.1 Determining Power of Traction Motor 10

3.1.2 Determining Traction Motor 12

3. 2 Determining Reduction Ratio of Final Drive 12

3.3 Check the Maximum Vehicle Speed 13

3.4 Check Peak Power for the Maximum Gradient 14

3.4.1 Improvement of Transmission 14

3.4.2 Determining Method of Improvement 14

3.4.3 Determining Form of the Mechanism 15

3.5 Check the Maximum Gradient with Improved Transmission 16

3.6 Check the Acceleration Time of the Miniature Pure Electric Vehicle 18

3.6.1 Determining the Time of Acceleration Time 18