Subject automotive electrical and electronic systems final report vehicle starting system

LIST OF FIGURES Figure 1: Early hand crank to start car Figure 2: Starter motor components Figure 3: Vehicle ignition switch Figure 4: Common starter relay Figure 5: Safety switch struct

MINISTRY OF EDUCATION AND TRAINING

HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY AND EDUCATION

FACULTY OF INTERNATIONAL EDUCATION

Subject: Automotive Electrical and Electronic Systems

Final Report

VEHICLE STARTING SYSTEM

Class ID: AEES330233E_02FIE Instructor: Đỗ Văn Dũng

Trần Đăng Long

Course: 2024 - 2025



TEAM MEMBERS LIST

Instructor comment:

Ho Chi Minh city, November 24th, 2024

LIST OF FIGURES

Figure 1: Early hand crank to start car

Figure 2: Starter motor components

Figure 3: Vehicle ignition switch

Figure 4: Common starter relay

Figure 5: Safety switch structure

Figure 6: Starter motor structure

Figure 7: General starting system circuit

Figure 8: Lipo rechargeable battery Lion Power Figure 9: Motor 775 132VDC

Figure 10: Relay 12VDC 10A

Figure 11: Relay 12VDC 30A

Figure 12: 1N4007 Rectifier Diode

Figure 13: Power switch off circuit

Figure 14: Power switch on circuit

Figure 15: Clutch switch closed circuit

Figure 16: Power switch open stage

Figure 17: Power switch closed stage

Figure 18: Clutch (Gear N or P) Switch closed

CONTENT

1 Introduction 1

1.1 Rationale of project 1

1.2 Scope and limitations 1

1.3 Goal of project 2

2 Review and theories of starting system 3

2.1 Historical review of starting system 3

2.2 Operation of starting system 5

2.3 Function of starting system 10

3 Building and testing of starting system 12

3.1 Components and preparation 12

3.2 Simulating staring system on Proteus 16

3.3 Building a realistic model 18

4 Conclusion 21

4.1 Inference of project 21

4.2 Further development for project 21

Reference 23

1 INTRODUCTION

1.1 Rationale of project

In the context of the ever-evolving automotive industry, the starting system plays a foundational role in the operation of any vehicle It is one of the core systems that ensure the engine can start quickly, safely, and efficiently Although it may appear simple, the starting system functions as the key that activates all vehicle operations, from running the engine to powering related systems

The starting system often encounters issues due to problems such as a weak battery, a malfunctioning starter motor, or poor electrical connections A solid understanding of the system allows technicians to easily identify the causes and provide effective repair solutions Additionally, studying modern starting systems (such as electronic, hybrid, or start-stop systems) helps reduce fuel consumption when the engine is not running continuously, thereby lowering emissions and protecting the environment

For these reasons, our group has chosen the topic “Vehicle Starting System” for our final report in the Automotive Electrical and Electronic Systems course Through this topic, we aim not only to enhance our technical knowledge but also

to contribute to the development of innovative solutions aligned with the trends

in the automotive industry

1.2 Scope and limitations

a Scope of Research

Explore the history and advancements of starting systems

Analyze in detail the operating principles of the main components in the starting system (starter motor, ignition switch, battery, relay, controller, etc.)

Conduct simulations of the starting system using specialized software such as Proteus and perform practical simulation tests to evaluate its applicability

Simulation tools: Utilize Proteus software and devices for assembling a model

of the starting system

1.3 Goal of project

The primary goal of this project is to explore, understand, and analyze the design, operation, and advancements of vehicle starting systems Through theoretical studies, simulations, and practical implementation, this project aims to:

Enhance knowledge of the historical development and functional principles of starting systems

Investigate the roles and interactions of key components such as the starter motor, battery, ignition switch, and relays

Utilize simulation tools to model and test starting systems, demonstrating their functionality and applicability

Build a realistic model to validate theoretical findings and practical skills, contributing to improved understanding and innovative applications in the automotive industry

2 REVIEW AND THEORIES OF STARTING SYSTEM

The car starting system is a system that helps rotate the engine crankshaft to a certain speed so that the engine can start and operate To start the engine, the crankshaft must rotate faster than the minimum rotation speed The minimum rotation speed to start the engine varies depending on the engine structure and operating condition, usually from 40-60 rpm for gasoline engines and 80-100 rpm for diesel engines The starting system on today's cars often uses a DC motor or motor, commonly known as a starter motor The starting system uses the car's battery as its power source These motors need to generate a large torque from the limited power source of the battery and must be compact

2.1 Developing history of starting system

The starting system of engines has evolved significantly over time, driven by advancements in technology and the need for convenience, reliability, and safety Here’s an overview of its development:

a Early Methods (1800s–Early 1900s)

Hand Crank: Early internal combustion engines were started using a crank handle The user had to physically turn the crankshaft to initiate engine operation This method is dangerous and strenuous; kickbacks could cause severe injuries

Hot Tube Ignition and Firing: In some steam or early gas engines, hot tubes or external flames were used to ignite the air-fuel mixture These methods were unreliable and labor-intensive

Figure 1: Early hand crank to start car

b Introduction of the Electric Starter (1910s)

The invention of the electric starter revolutionized starting systems:

- 1912 Cadillac Model 30: The first mass-produced car with an electric starter, designed by Charles Kettering and manufactured by Delco

- It eliminated the need for hand cranking

- It comprised an electric motor, a solenoid, and a small battery

- Impact: Made automobiles more accessible, especially for women, and significantly improved safety

c Advancements in Starter Technology (1930s–1950s)

Improved Motors and Solenoids: Enhanced reliability and efficiency

12-Volt Electrical Systems: Introduced in the 1950s, replacing 6-volt systems This allowed for more powerful starters and additional electrical components in vehicles

Key Ignition Systems: Drivers could now start engines by turning a key, simplifying the process further

d Starter-Generator Systems (1960s–1980s)

Dual-function systems combined the starter and alternator into one unit, commonly used in small engines (e.g., motorcycles, lawnmowers)

e Modern Push-Button and Remote Starters (2000s–Present)

Keyless Start Systems: Proximity sensors and smart keys enable push-button ignition This enhances convenience and integrates with advanced vehicle security systems

Remote Start: Allows drivers to start engines from a distance using a key fob or smartphone app This is useful for preconditioning the cabin (heating or cooling) before entering

f Start-Stop Systems (2000s–Present)

Start-stop system is introduced to improve fuel efficiency and reduce emissions

It automatically shuts off the engine when idle and restarts it upon pressing the accelerator or releasing the brake The system is integrated with advanced sensors and control systems

2.2 Structure and function of car starting system

The car starting system consists of 6 parts: car battery, ignition switch, starter relay, starter safety switch, starter motor and battery cable Each of these parts will perform a different task and when working together they create a complete system

Figure 2: Starter motor components

a Car batteries

A car battery is a power storage device that is used to start the system and is located in the engine compartment A battery is an electrical device that can store electricity in chemical form and convert it into electric current when needed

The purpose of a car battery is to provide electricity to all circuits and other parts such as the ignition system that are running or to provide additional current when the demand is higher than the generator can provide

There are many types of car batteries, but the most common and widely equipped is the lead-acid battery This type of battery contains lead (Pb) plates immersed in a liquid mixture of sulfuric acid (H2SO4) and water When fully charged, this mixture contains 40% sulfuric acid and 60% water

Some things about car batteries you need to note:

In essence, car batteries do not store electricity directly but in chemical form The battery works thanks to the chemical reaction between the lead plate and the

car with electricity - Hydrogen gas emitted while charging the battery is very flammable, so you need to be very careful while charging the battery

b Ignition switch

As a component of the system and considered as the “gateway” of all circuits, the ignition switch has the function of distributing current to the necessary places on the car starting system

On the car starting system, the ignition switch is distributed in the following four positions:

- Lock: the position where the key is inserted but not turned In this position, all circuits are turned off and the steering wheel is locked The key can only be removed when it is in the lock position

- Off: the default position, in the Off position, all circuits are “turned off” (no current is supplied) At that time, the steering wheel can be turned but the key cannot be removed

- Running: the position where the key is still in the lock, when the engine has started At this time, current is supplied to all components except the circuit of the starting system

- Accessories: current is supplied to all accessories (components) except the starting and ignition systems At that time, the current is only allowed to flow to accessories such as radio, lighter, windows - Start: in this position, the current will be supplied to the starting and ignition system, it is cut off from all accessories This is the reason why the windows and other accessories stop working when the engine is started The correct distribution of current helps to save battery and shorten the time to start the car

Figure 3: Vehicle ignition switch

c Starter relay

A starter relay is a device that allows a small amount of electricity to control a large amount of current Although it is a small part, the relay plays a very important role in the car starting system The starter motor needs to use a large amount of current, 250+ amps to be exact This is a large current, which cannot

be controlled directly from the ignition switch, so a relay is used in the circuit to control the starting process of this current

Figure 4: Common starter relay

d Start safety switch

The starter safety switch is a part of the gear range switch, which prevents the starter system from operating when the car is in gear (in automatic transmission), or the clutch pedal is not pressed (in manual transmission) The role of this switch is to ensure that the car does not start while in gear mode to avoid the car accidentally jerking forward or backward, causing unsafety for the driver when starting

Figure 5: Safety switch structure

For each type of transmission, a separate type of safety switch will be equipped:

- Manual transmission (manual transmission) uses a clutch pedal safety switch

- Automatic transmission uses a neutral parking position switch

e Starter motor

Mounted on the back of the engine housing or on the gearbox housing where the engine and gearbox meet, the starter motor is an essential part of the starting system on a car It is a device that converts electrical energy into mechanical energy in the micro-circuit engine When operating, the starter motor creates torque to rotate the engine's flywheel and make the car turn around

- The solenoid is an electromagnetic switch that connects and disconnects the battery from the starter motor assembly It functions as a larger relay, using a small current to stimulate a large current

- The starter motor assembly consists of many parts including: armature, commutator, carbon brushes, spur gear, overspeed clutch These parts combine

to form a complete motor assembly

Figure 6: Starter motor structure

f Battery cable

Battery cables, also known as battery cables, are large diameter, multi-stranded wires that carry the high currents (250+ amps) required to operate a starter motor Some battery cables have a smaller wire soldered to the terminal and used to operate a smaller device

2.3 Operating principle of car starting system

a Intake

When the ignition is turned on, the battery current flows along with the holding coil and the pull coil The current will flow from the pull coil to the inductor, causing the reaction coil to rotate at a low speed This creates electromagnetic

Therefore, the piston of the switches will be pulled and the pole core of the electromagnet Thanks to this pull, the drive gear will easily engage with the

flywheel, and at the same time contact the contact plate to turn the switch on

b Hold

When the main switch is turned on, there is no current flowing through the holding coil and the inductor The induction coil receives electricity directly from the battery The reaction coil after receiving electricity will start rotating at

a high speed and the engine will be started At this point, the piston is held still

c Release

When the ignition is moved from the START button to the ON button position The current will move from the main switch side through the pull coil to the holding coil In this position, the electromagnetic force created by the coil pulling on the holding coil cancels each other out, so the piston can no longer be held Therefore, the piston is pulled back by the return spring and the main switch is disconnected, causing the starter to stop

Figure 7: General starting system circuit