Abstract

In today's society, with the intensification of energy and environmental issues, purely electric vehicles as the only vehicle that can achieve zero emissions have achieved unprecedented rapid development. The electric wheel drive technology has become an important development direction in the field of electric vehicles with its unique advantages. The electric wheel is a driving wheel that integrates the motor and the wheel and can realize the independent driving of the wheel of the electric vehicle. Wheels generally have a wheel reducer.

This paper analyzes the research status and major problems of the electric wheel drive technology for cars at home and abroad. The design of the electric wheel is completed under the limitation of the reference vehicle's inner space and its dynamic performance requirements. A three-dimensional model was built using SolidWorks to verify the rationality of the structure.

The specific work of the dissertation is as follows: First, analyze the basic conditions of the front and rear wheels of the reference model, and complete the selection of the hub motor according to the dynamic performance of the vehicle. Then determine the main components in the wheel, complete the selection of the power transmission mode of the electric wheel, determine the connection mode of each component, and determine the overall layout of the electric wheel, providing a basis for structural modeling. Finally, the structural design of the electric wheel is completed according to the overall layout plan of the electric wheel. According to the design parameters of each part, through the SolidWorks technology, the rationality of the modeling and verification structure of the electric wheel is completed.

Key Words：Electric vehicle; Structural design; SolidWorks; in-wheel motor

catalogUE

Abstract I

Chapter 1 Introduction 1

1.1 Purpose and significance 1

1.1.1 Background and Significance of Selected Topics 1

1.1.2 Research Status analysis outside the country 1

1.2 Electric wheel drive technology 2

Chapter 2 Electric wheel total design 5

2.1 Main content of electric wheel design 5

2.2 Base model of electric wheel design 5

2.3 Determination of electric wheel vehicle drive 5

2.4 Chapter summary 6

Chapter 3 selection of In-wheel motor 6

3.1 Power balance equation 6

3.2 The calculation of in-wheel motor 8

3.3 Chapter summary 12

Chapter 4 Shaft design 12

4.1 Rotor shaft design and check 12

4.2 Sun wheel shaft design and check 13

4.3 Collaboration of sun wheel and sun wheel shaft 13

4.4 Chapter summary 14

Chapter 5 Wheel bearing life check 14

5.1 Vehicle and working condition analysis 14

5.2 Bearing equivalent dynamic load calculation 15

5.3 Calculation of bearing life 16

Chapter 6 Speed reduction mechanism design 16

6.1 Planetary gear transmission 16

6.2 Planetary gear teeth design 16

6.3 Sun wheel design 17

6.4 Determination of planetary mechanism parameters 19

6.5 Chapter summary 20

Chapter 7 Summary 20

Acknowledgements 21

References 22

Chapter 1 Introduction

1.1 Purpose and significance

1.1.1 Background and Significance of Selected Topics

In recent years, China's automobile industry has developed rapidly, according to statistical data, to 2016, China's auto output is expected to exceed 30 million. Car ownership in 31 cities across the country exceeded 1 million in 2013. However, along with the rapid development of the automobile industry, the domestic environment has also suffered tremendous damage. In recent years, the haze phenomenon in China has been particularly serious. One of the main causes of these environmental problems is that most of the cars still rely on traditional internal combustion engine cars that burn fossil fuels. Due to problems such as environmental pollution, noise, and energy shortage caused by traditional internal combustion engine vehicles, people began to urgently need to find a suitable energy source to replace fossil energy. Electric vehicles gradually shift their focus to the field of electric vehicles with the advantages of low emissions, low noise, etc. At present, the world's major auto-producing countries regard electric vehicles as the future development direction, and the electric vehicle industry has developed rapidly. Currently, wheel hub drive technology is one of the most promising directions in the field of electric vehicles.

Actually, American Robert applied for an American invention patent integrating the brake system, electric motor and drive train in the hub as early as the 1950s. It is the earliest electric wheel prototype. The device was later applied to large mining dump truck. In recent years, due to the rapid development of science and technology and manufacturing industry, the performance of automotive motors has been greatly improved. Experts and scholars at home and abroad have gradually focused on wheel hub motor drive technology, and wheel hub motor drive technology is attracting the attention of the world.

1.1.2 Research Status analysis outside the country

The application of wheel hub motors in automobiles can be traced back to the 50s of the last century. The American Robert applied for an invention patent, which integrates the brake system, the drive train, and the motor into the wheel hub, and is the earliest form of electric wheel. In 1968, General Electric of the United States applied the electric wheel device to a large mining dump truck ^[1].