Automotive Electricity

Electric Drives

Joseph Beretta

• Publisher: Wiley-ISTE
• Year: 2013
• ISBN:
  9781118617373
• Edition: 1
• Topic: Tecnología e ingeniería
• Subtopic: Recursos energéticos

Since the beginning of the century, electrical engineering technologies and applications have pervaded daily life and are present in the majority of everyday products, tools, and appliances. Increasingly these applications are becoming more prevalent in the automotive vehicle and products market. While change in this field has been relatively slow over the last ten last years, the pace of change is now beginning to accelerate and we are witnessing a wave driven by regulatory constraints and market laws which are sweeping away the last bastions of resistance.

This book discusses both the historical and scientific issues surrounding the application of electrical technology in the automotive drives field, as well as potential future developments, such as hybrid vehicles and fuel cells. In the current context of energy conservation, pollution prevention, and carbon control, this book will provide an important and timely examination of a potentially enormous new market.

Chapter 1

Introduction ¹

Throughout the history of Mankind, human beings have endeavored to extend the radius of their activities, which has always led them to improve transport techniques.

Each time new progress was made with transport, this altered humans’ lives. Today, it is mobility concepts that are the focus. This mobility has multiple implications; it supports the choices made for our environment, the rules of traveling and the design of “automobiles” (cars). It is to cars themselves, and particularly to automotive electrical engineering, that we devote this work.

We will review all of the electric technologies that are used, with this first volume focusing on technologies relating to electric drive-trains.

1.1. Automotive constraints

Having come into existence more than one hundred years ago, cars are now a predominant part of our everyday lives. It is a very original “thing”, which, as the years have passed, has managed to make a place for itself as a method of transport, a high-tech object, a consumer good and a representation of our social behavior.

The future of this “thing” in the coming years is thus a captivating subject for thought.

The car, this method of preserving our individual freedom as we travel, today forms part of our daily life, and has largely surpassed its functional role; it is a symbol representing our identity and our subconscious.

Whereas in the past, during the growth phase of this market, work was primarily entrusted to engineers, today it is a process which closely associates both technical and market roles.

This goes as far as anticipating customer expectations by introducing innovations which offer new products or services corresponding to latent needs.

Success in this field will come from a subtle mixture of pragmatic vision and the mastering of technology. In this combination, electricity will play a fundamental role and will contribute to achieving the new goals of the automotive industry in terms of safety, comfort and environment.

1.2. Key figures from the automotive industry — data from the CCFA (association of French car manufacturers)

The automotive industry is a first-rank industry as a result of its significant presence.

For France, the car manufacturing sector represents 100 billion Euros in turnover, i.e. 5 to 6% of the GDP (gross domestic product), and it employs 350,000 people.

In the same vein, the entire automotive sector represents around 2.5 million jobs (including 450,000 in upstream industries, 600,000 in services related to usage and 1 million in the transportation of goods and travelers). Research and development play an important role, with 17,000 jobs and 8 billion Euros largely financed on equity.

The worldwide automotive market, which has been in constant progression since 1998, represented nearly 70.3 million PV + LCV¹ units in 2007 (4.1% growth). This growth draws more on the emerging markets (China, India, Iran, Mercosur, etc.) than on the historically large markets of North America, Western Europe and Japan.

The evolution of worldwide automotive sales since 2000 has been marked by stability, even the relative stagnation of the Western Europe and North-America markets. The Asian market, meanwhile, has grown by more than one million units each year since 2000, benefiting in particular from China’s economic ascension.

The situation of the European automotive market largely reflects the economic circumstances of the various countries within the zone. In Germany, where the economy is marked by relative gloom, the automotive market has been in constant decline since 2000.

In France, the market has also registered a slight drop because of a lack of vigor in household consumption and the tendency to put money into savings, amidst a context of persistent unemployment. Another basic tendency of the European market is the regular progression of diesel motorizations: their share, on the passenger-vehicle market, rose from 24.8% in 1998 to 52.6% in 2007.

The continent of North America is today the world’s number-one zone in terms of automotive sales, with 23.8 million units in 2007. Just like Western Europe, the North-American markets (the United States and Canada along with Mexico) have presented relative sales stability.

North America is characterized by the prevalence of “light trucks”, i.e. pick-ups, vans and large all-terrain vehicles. For several years the North-American market has been experiencing a major price-war between the various manufacturers involved. The “Big Three”, that is, the three historically major American manufacturers, namely General Motors, Ford and DaimlerChrysler, have been suffering a constant erosion of their market shares because of the constant progression of Japanese and Korean constructors.

The Asia-Pacific zone is characterized by the sustained development of its automotive market. This “boom” reflects above all the dynamism of China, which recorded a GDP increase of more than 11% in 2007 and saw its market increase by almost 40% for several consecutive years.

Japan, the number-one market within the zone and the world’s second largest automotive market, is characterized by sales stability. The Japanese market is very slowly opening up to foreign automotive imports.

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1 Chapter written by Joseph BERETTA

1 PV = passenger vehicles, LCV = light commercial vehicles (under 3.5 T).

Chapter 2

Basic Definitions ¹

2.1. Basic concepts

2.1.1. Basics of automotive energy

Most of the energy introduced into a vehicle is lost during transfers (friction, heat, pumping). Manufacturers continue to explore a number of possibilities for reducing these losses.

To talk about energetic concepts, we need to talk about efficiency.

Efficiency is the ratio of energy used with respect to the work involved in setting the vehicle in motion. It directly affects the consumption: the greater the efficiency, the lower the fuel consumption of the car.

– Let us examine how energy in a car is reduced.

When energy is introduced into an engine, only 30% remains when it comes to setting the wheels in motion. There are, throughout the process, losses which lower the efficiency. We estimate that 30% of energy is lost in the form of heat from the engine, approximately 30% leaves in the exhaust gas and 10% is dissipated by mechanical friction and driving the accessories (water pump, air-conditioning, etc.).

On arrival, the remaining 30% are reduced slightly further by the mechanical efficiency of the gear box and the transmissions.

Some of these losses are used to provide other services: the heat released by the cooling system is thus used for heating the cabin, the heat released through the exhaust supports the post-treatment mechanisms.

– Each transformation has its own efficiency.

The total efficiency of an engine (equal to 0.3 in the best cases) is the relationship between the energy supplied to the crankshaft and the energy supplied by the fuel. More precisely, it is the result of the product of two outputs:

1) The efficiency of the chemical reaction, which breaks down into:

– theoretical thermodynamic efficiency of the driving cycle, which depends on the compression ratio;

– efficiency with the additional losses, which expresses the actual reduction compared to the theoretical reduction (inertia, viscosity, pumping, etc.);

– efficiency of combustion (combustion does not use all the energy supplied by the fuel).

2)The mechanical efficiency, which comes ...

Table of contents

• Cover
• Title Page
• Copyright
• Preface
• Chapter 1: Introduction
• Chapter 2: Basic Definitions
• Chapter 3: Electric-Powered Vehicles
• Chapter 4: The Components of Electric-Powered Vehicles
• Chapter 5: Prospects and Evolutions of Electric-Powered Vehicles: What Technologies by 2015?
• Automobile Glossary
• Appendices
• List of authors
• Index