HYBRID ELECTRIC VEHICLE

Chapter-1

INTRODUCTION

1.1 INTRODUCTION OF HYBRID ELECTRIC VEHICLE

A hybrid vehicle, abbreviated HEV, is one that uses both an internal combustion engine

(ICE) and an electric motor to propel the vehicle. Most hybrids use a high-voltage battery

pack and a combination electric motor and generator to help or assist a gasoline engine.

The ICE used in a hybrid vehicle can be either gasoline or diesel, although only gasoline-

powered engines are currently used in hybrid vehicles. An electric motor is used to help

propel the vehicle, and in some designs, capable of propelling the vehicle alone without

having to start the internal combustion engine.

The presence of the electric power train is intended to achieve either better fuel economy

than a conventional vehicle or better performance. There are a variety of HEV types, and

the degree to which they function as EVs varies as well. The most common form of HEV

is the hybrid electric car, although hybrid electric trucks (pickups and tractors) and buses

also exist. Modern HEVs make use of efficiency-improving technologies such as

regenerative braking, which converts the vehicle's kinetic energy into electric energy to

charge the battery, rather than wasting it as heat energy as conventional brakes do. Some

varieties of HEVs use their internal combustion engine to generate electricity by spinning

an electrical generator (this combination is known as a motor-generator), to either

recharge their batteries or to directly power the electric drive motors. Many HEVs reduce

idle emissions by shutting down the ICE at idle and restarting it when needed; this is

known as a start-stop system. A hybrid-electric produces less emissions from its ICE than

a comparably-sized gasoline car, since an HEV's gasoline engine is usually smaller than a

comparably-sized pure gasoline-burning vehicle (natural gas and propane fuels produce

lower emissions) and if not used to directly drive the car, can be geared to run at

maximum efficiency, further improving fuel economy.

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Chapter-2

HISTORY OF HYBRID ELECTRIC VEHICLE

2.1 HISTORY OF HYBRID ELECTRIC VEHICLE

In 1900 Ferdinand Porsche developed the Lohner-Porsche Mixte Hybrid, the first

gasoline-electric hybrid automobile in the world, a 4WD series-hybrid version of "System

Lohner-Porsche" electric carriage previously appeared in 1900 Paris World Fair. The

Mixte included a pair of generators driven by 2.5-hp Daimler IC engines to extend

operating range and it could travel nearly 65 km on battery alone. It was presented in the

Paris Auto Show in 1901. The Mixte broke several Austrian speed records, and also won

the Exelberg Rally in 1901 with Porsche himself driving. The Mixte used a gasoline

engine powering a generator, which in turn powered electric hub motors, with a small

battery pack for reliability. It had a top speed of 50 km/h and a power of 5.22 kW during

20 minutes.George Fischer sold hybrid buses to England in 1901; Knight Neftal produced

a racing hybrid in 1902.

Fig. 2.1 The first gasoline-electric hybrid vehicle

In 1905, Henri Pieper of Germany/Belgium introduced a hybrid vehicle with an electric

motor/generator, batteries, and a small gasoline engine. It used the electric motor to

charge its batteries at cruise speed and used both motors to accelerate or climb a hill. The

Pieper factory was taken over by Imperia, after Pieper died. The 1915 Dual Power, made

by the Woods Motor Vehicle electric car maker, had a four-cylinder ICE and an electric

motor. Below 15 mph (24 km/h) the electric motor alone drove the vehicle, drawing

power from a battery pack, and above this speed the "main" engine cut in to take the car

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up to its 35 mph (56 km/h) top speed. About 600 were made up to 1918. The Woods

hybrid was a commercial failure, proving to be too slow for its price, and too difficult to

service. The United States Army's 1928 Experimental Motorized Force tested a gasoline-

electric bus in a truck convoy. In 1931 Erich Gaichen invented and drove from Altenburg

to Berlin a 1/2 horsepower electric car containing features later incorporated into hybrid

cars. Its maximum speed was 25 miles per hour (40 km/h), but it was licensed by the

Motor Transport Office, taxed by the German Revenue Department and patented by the

German Reichs-Patent Amt. The car battery was re-charged by the motor when the car

went downhill. Additional power to charge the battery was provided by a cylinder of

compressed air which was re-charged by small air pumps activated by vibrations of the

chassis and the brakes and by igniting oxy-hydrogen gas. An account of the car and his

characterization as a "crank inventor" can be found in Arthur Koestler's autobiography,

Arrow in the Blue, pages 269-271, which summarize a contemporaneous newspaper

account written by Koestler. No production beyond the prototype was reported. The

hybrid-electric vehicle did not become widely available until the release of the Toyota

Prius in Japan in 1997, followed by the Honda Insight in 1999.While initially perceived

as unnecessary due to the low cost of gasoline, worldwide increases in the price of

petroleum caused many automakers to release hybrids in the late 2000s; they are now

perceived as a core segment of the automotive market of the future. More than 5.8 million

hybrid electric vehicles have been sold worldwide by the end of October 2012, led by

Toyota Motor Company (TMC) with more than 4.6 million Lexus and Toyota hybrids

sold by October 2012, followed by Honda Motor Co., Ltd. with cumulative global sales

of more than 1 million hybrids by September 2012, and Ford Motor Corporation with

more than 200 thousand hybrids sold in the United States by June 2012. Worldwide sales

of hybrid vehicles produced by TMC reached 1 million units in May 2007; 2 million in

August 2009; and passed the 4 million mark in April 2012.As of October 2012,

worldwide hybrid sales are led by the Toyota Prius liftback, with cumulative sales of 2.8

million units, and available in almost 80 countries and regions.The United States is the

world's largest hybrid market with more than 2.5 million hybrid automobiles and SUVs

sold through October 2012, followed by Japan with more than 2 million hybrids sold

through October 2012 The Prius is the top selling hybrid car in the U.S. market,

surpassing the 1 million milestone in April 2011. Cumulative sales of the Prius in Japan

reached the 1 million mark in August 2011.

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Chapter-3

TYPES BY DEGREE OF HYBRIDIZATION

3.1 FULL HYBRID

Full hybrid, sometimes also called a strong hybrid, is a vehicle that can run on just the

engine, just the batteries, or a combination of both. It use a gasoline engine as the primary

source of power, and an electric motor provides additional power when needed. In

addition, full hybrids can use the electric motor as the source of population for low-speed,

low acceleration driving, such as stop-and-go traffic or for backing up.Ford's hybrid

system, Toyota's Hybrid Synergy Drive and General Motors/Chrysler's Two-Mode

Hybrid technologies are full hybrid systems The Toyota Prius, Ford Escape Hybrid, and

Ford Fusion Hybrid are examples of full hybrids, as these cars can be moved forward on

battery power alone. A large, high-capacity battery pack is needed for battery-only

operation. These vehicles have a split power path allowing greater flexibility in the drive-

strain by inter-converting mechanical and electrical power, at some cost in complexity.

Fig. 3.1 Full hybrid vehicle-Toyota Prius (2nd generation)

3.2 MILD HYBRID

Mild hybrid, sometimes also called a stop-start hybrid is a vehicle that cannot be driven

solely on its electric motor, because the electric motor does not have enough power to

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propel the vehicle on its own. Stop-start technology conserves energy by shutting off the

gasoline engine when the vehicle is at rest, such as at a traffic light, and automatically re-

starting it when the driver pushes the gas pedal to go forward. Mild hybrids only include

some of the features found in hybrid technology, and usually achieve limited fuel

consumption savings, up to 15 percent in urban driving and 8 to 10 percent overall cycle

A mild hybrid is essentially a conventional vehicle with oversize starter motor, allowing

the engine to be turned off whenever the car is coasting, braking, or stopped, yet restart

quickly and cleanly. The motor is often mounted between the engine and transmission,

taking the place of the torque converter, and is used to supply additional propulsion

energy when accelerating. Accessories can continue to run on electrical power while the

gasoline engine is off, and as in other hybrid designs, the motor is used for regenerative

braking to recapture energy. As compared to full hybrids, mild hybrids have smaller

batteries and a smaller, weaker motor/generator, which allows manufacturers to reduce

cost and weight. Honda's early hybrids including the first generation Insight used this

design, leveraging their reputation for design of small, efficient gasoline engines; their

system is dubbed Integrated Motor Assist (IMA). Starting with the 2006 Civic Hybrid,

the IMA system now can propel the vehicle solely on electric power during medium

speed cruising. Another example is the 2005-2007 Chevrolet Silverado Hybrid, a full-size

pickup truck. Chevrolet was able to get a 10% improvement on the Silverado's fuel

efficiency by shutting down and restarting the engine on demand and using regenerative

braking. General Motors has also used its mild BAS Hybrid technology in other models

such as the Saturn Vue Green Line, the Saturn Aura Greenline and the Mailbu Hybrid.

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Fig. 3.2 Mild hybrid vehicle-Honda Civic

Chapter-4

TYPES OF HYBRID ELECTRIC VEHICLE

4.1 SERIES TYPE HEV

In series hybrids, only the electric motor drives the drive-strain, and the ICE works as a

generator to power the electric motor or to recharge the batteries. The battery pack can be

recharged through regenerative braking or by the ICE. Series hybrids usually have a

smaller combustion engine but a larger battery pack as compared to parallel hybrids,

which makes them more expensive than parallels. This configuration makes series

hybrids more efficient in city driving. The Chevrolet Volt is a series plug-in hybrid,

although GM prefers to describe the Volt as an electric vehicle equipped with a "range

extending" gasoline powered ICE as a generator and therefore dubbed an "Extended

Range Electric Vehicle" or EREV. Means In a series driveline, only an electric motor is

connected to drive the wheels. In it gasoline motor turns a generator, ggenerator may

either charge the batteries or power an electric motor that drives the transmission and at

low speeds is powered only by the electric motor. In a series-hybrid design, the engine

turns a generator, which can charge batteries or power

an electric motor that drives the transmission. The internal combustion engine

never powers the vehicle directly.

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Fig. 4.1 Series type HEV

Fig. 4.2 Series type HEV

This diagram shows the components included in a typical series hybrid design. The solid-

line arrow indicates the transmission of torque to the drive wheels. The dotted-line arrows

indicate the transmission of electrical current.

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Fig. 4.3 Power flow in series type HEV

4.2 PARALLEL TYPE HEV

In parallel hybrids, the ICE and the electric motor are both connected to the mechanical

transmission and can simultaneously transmit power to drive the wheels, usually through

a conventional transmission. Honda's Integrated Motor Assist (IMA) system as found in

the Insight, Civic, Accord, as well as the GM Belted Alternator/Starter (BAS Hybrid)

system found in the Chevrolet Malibu hybrids are examples of production parallel

hybrids. Current, commercialized parallel hybrids use a single, small (<20 kW) electric

motor and small battery pack as the electric motor is not designed to be the sole source of

motive power from launch. Parallel hybrids are also capable of regenerative braking and

the internal combustion engine can also act as a generator for supplemental recharging.

Parallel hybrids are more efficient than comparable non-hybrid vehicles especially during

urban stop-and-go conditions and at times during highway operation where the electric

motor is permitted to contribute. Means in a parallel system, both the gasoline and the

electric motor are connected to the drive wheels. Gasoline motor,batteries which powers

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an electric motor,both can power the transmission at the same time and electric motor

supplements the gasoline engine. In a parallel-hybrid design, multiple propulsion sources

can be combined, or one energy source alone can drive the vehicle. The battery and

engine are both connected to the transmission. The vehicle can be powered

by internal combustion alone, by electric motor alone, (full hybrids), or a combination. In

most cases, the electric motor is used to assist the internal combustion engine.

Fig. 4.4 Parallel type HEV

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Fig. 4.5 Parallel type HEV

Diagram showing the components involved in a typical parallel-hybrid vehicle. The solid-

line arrows indicate the transmission of torque to the drive wheels, and the dotted-line

arrows indicate the flow of electrical current.

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Fig. 4.6 Power flow in parallel type HEV

4.3 SERIES-PARALLEL TYPE HEV

Series-Parallel type also called Power-split hybrids have the benefits of a combination of

series and parallel characteristics. As a result, they are more efficient overall, because

series hybrids tend to be more efficient at lower speeds and parallel tend to be more

efficient at high speeds; however, the cost of power-split the hybrid is higher than a pure

parallel. Examples of power-split (referred to by some as "series-parallel") hybrid power-

strains include current models of Ford, General Motors, Lexus, Nissan, and Toyota.

Means a series-parallel hybrid design allows the vehicle to operate in electric motor mode

only or in combination with the internal combustion engine. In it characteristics of both

series and parallel type hybrid electric vehicle are used, it’s cost is more than both single

type HEV’s.

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Fig. 4.7 Series- parallel type HEV

Chapter-5

PARTS OF HYBRID ELECTRIC VEHICLE

5.1 ENGINE

It’s much same as other vehicles engine, but the size of hybrid electric vehicle engine is

small and it’s more fuel efficient.

Higher energy density than batteries,

1,000 pounds of batteries = 1 gallon (7 pounds) of gas.

It has three types

5.1.1 Gasoline engine

Gasoline engines are used in most hybrid electric designs, and will likely remain

dominant for the foreseeable future. While petroleum-derived gasoline is the

primary fuel, it is possible to mix in varying levels of ethanol created from

renewable energy sources. Like most modern ICE powered vehicles, HEVs can

typically use up to about 15% bio-ethanol. Manufacturers may move to flexible

fuel engines, which would increase allowable ratios, but no plans are in place at

present.

5.1.2 Diesel engine

Diesel-electric HEVs use a diesel engine for power generation. Diesels have

advantages when delivering constant power for long periods of time, suffering less

wear while operating at higher efficiency. The diesel engine's high torque,

combined with hybrid technology, may offer substantially improved mileage.

Most diesel vehicles can use 100% pure bio-fuels (biodiesel), so they can use but

do not need petroleum at all for fuel (although mixes of bio-fuel and petroleum are

more common). If diesel-electric HEVs were in use, this benefit would likely also

apply. Diesel-electric hybrid drive-strains have begun to appear in commercial

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vehicles (particularly buses); as of 2007, no light duty diesel-electric hybrid

passenger cars are currently available, although prototypes exist.

5.1.3 Hydrogen engine

Hydrogen can be used in cars in two ways: a source of combustible heat, or a

source of electrons for an electric motor. The burning of hydrogen is not being

developed in practical terms; it is the hydrogen fuel-cell electric vehicle (HFEV)

which is garnering all the attention. Hydrogen fuel cells create electricity fed into

an electric motor to drives the wheels. Hydrogen is not burned, but it is consumed.

This means molecular hydrogen, H2, is combined with oxygen to form water.

2H2(4e-) + O2 --> 2H2O(4e-). The molecular hydrogen and oxygen's mutual

affinity drives the fuel cell to separate the electrons from the hydrogen, to use

them to power the electric motor, and to return them to the ionized water

molecules that were formed when the electron-depleted hydrogen combined with

the oxygen in the fuel cell. Recalling that a hydrogen atom is nothing more than a

proton and an electron; in essence, the motor is driven by the proton's atomic

attraction to the oxygen nucleus, and the electron's attraction to the ionized water

molecule.

An HFEV is an all-electric car featuring an open-source battery in the form of a

hydrogen tank and the atmosphere. HFEVs may also comprise closed-cell

batteries for the purpose of power storage from regenerative braking, but this does

not change the source of the motivation. It implies the HFEV is an electric car

with two types of batteries. Since HFEVs are purely electric, and do not contain

any type of heat engine, they are not hybrids.

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Fig. 5.1 Cost per mile EV v/s Gasoline Engine

5.2 BATTERY

It store the energy generated from gasoline engine or during regenerative braking, from

the electric motor. It’s power the vehicle at low speed, it’s size is larger and holds much

more energy than non-hybrid electric vehicle.

Batteries rule the performance of the vehicle

They dictate how much power you get (kW)

They dictate how much energy you get (kWh)

A single cell dictates the battery voltage each cell mates two dissimilar materials

Fig. 5.1 Battery types

5.2.1 Batteries packaging

Cylindrical

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Fig. 5.2 Cylindrical type battery packaging

Prismatic

Fig. 5.3 Prismatic type battery packaging

Button

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Fig. 5.4 Button type battery packaging

Pouch

Fig. 5.5 Pouch type battery packaging

5.2.2 Basic Characteristics

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State of Charge (SOC)

Measured as a percentage of total battery energy (0-100%)

Typically should not go below 20%

Depth of Discharge (DoD)

Inverse of SOC

Power (kW)

Energy (kWh)

A-h

Typically used for power batteries

Cells often described in mA-h

C Rate

A normalized rate of power use to qualify testing

100% discharge divided by the time in hours

C2 means the discharge rate was 100% in ½ hour

C/2 means the rate was less aggressive – over 2 hours

Cycle Life

Always measured based on DoD

Ex. 1000 cycles at 80% DoD

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Fig. 5.6 Cycle life

Weight/Volume

Measures in terms of

W/kg and W-h/kg

W/l and W-h/l

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Fig. 5.7 Energy Densities

5.3 ELECTRIC MOTOR

It’s power the vehicle at low speed and assist the gasoline engine when additional power

is needed, it’s also convert otherwise wasted energy from braking into electricity and

store it in battery. Most of the electric machines used in hybrid vehicles are brushless DC

motors (BLDC). Specifically, they are of a type called an interior permanent magnet

(IPM) machine (or motor). These machines are wound similarly to the induction motors

found in a typical home, but (for high efficiency) use very strong rare earth magnets in

the rotor. These magnets contain neodymium, iron and boron, and are therefore called

Neodymium magnets. The magnet material is expensive, and its cost is one of the limiting

factors in the use of these machines.

5.3.1 Motor components

Rotating components

[1] Shaft

[2] Rotor

[3] Rotor fins

[4] Fan

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Housing components

[5] End bells / bearing housings

[6] Stator housing

[7] Cooling fins

[8] Junction box

[9] Fan shroud

Fixed components

[10] Seals

[11] Stator windings

[12] Core iron / lamination stack

[13] Bearings

Fig. 5.8 Motor Parts

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5.3.2 Components: Electric Motor – DC

Fig. 5.9 Components: Electric Motor – DC

5.3.3 Components: Electric Motor – AC

Fig. 5.10 Components: Electric Motor – AC

5.4 CONTROLLER

The controller is used to charge the battery or to supply the power to electric motor.

Converts Battery DC to a chopped DC power

Can chop in amplitude (DC) or frequency (AC)

Power is based on low voltage input signal

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4-20 mA or 0-5V

In other fields this is called a drive or inverter

Variable Frequency (AC)

Pulse Width Modulation (AC)

Buck Conversion (Reduce - DC)

Boost Conversion (Increase - DC)

5.5 GENERATOR

It convert mechanical energy from engine into electrical energy, which can be used by

electric motor stored in the battery. It’s also used to start the gasoline engine instantly.

5.6 POWER SPLIT DEVICE

It’s a gearbox connecting the gasoline engine, electric motor and generator. It allows the

engine and motor to power the car independently or in tandem and allows the gasaoline

engine to charge the batteries or provide power to the wheels as needed

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Fig. 5.11 Parts of HEV

Chapter-6

FEATURES OF HYBRID ELECTRIC VEHICLE

6.1 IDLE STOP

Idle stop turns off engine when the vehicle is stopped. When the brake is released, the

engine immediately starts. This ensures the vehicle is not using fuel, not creating CO2

emissions, when the engine is not required to propel the vehicle. At this time battery

supply the power to all accessories of vehicle like AC, DVD Player etc.

6.2 REGENERATIVE BRAKING

Regenerative braking converts otherwise wastage energy from braking into electricity and

store it in the battery. In regenerative braking the electric motor is reversed so that,

instead of using electricity to turns the wheels, the rotating wheels turns the motor and

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create electricity. Using energy from the wheels to turn the motor slows the vehicle down.

When decelerating, the braking system captures energy and stores it in the battery or

other device for later use, helping to keep batteries charged.

In motor case “Eb = V - IaRa“ Generally Eb < V

Here, Eb = Back emf of motor

V = Terminal voltage/Load side voltage

Ia = Armature current and

Ra = Armature resistance

But in regenerative braking system Eb > V, means the load supplies the power to motor.

6.3 POWER ASSIST

The electric motor provides extra power using current drawn from the battery to assist

ICE during acceleration. This power-assist mode enables the vehicle to use a smaller,

more fuel-efficient engine without giving up performance.

6.4 ENGINE-OFF DRIVE ELECTRIC VEHICLE MODE

In this mode the electric motor propels the vehicle at lower speeds. The ICE is not being

used during low acceleration, no fuel is being used and no emissions are being released.

When the hybrid is in this mode, it is essentially in an electric vehicle.

6.5 PLUG-IN HYBRIDS (PHEV)

A plug-in hybrid electric vehicle (PHEV), also known as a plug-in hybrid, is a hybrid

electric vehicle with rechargeable batteries that can be restored to full charge by

connecting a plug to an external electric power source. A PHEV shares the characteristics

of both a conventional hybrid electric vehicle, having an electric motor and an internal

combustion engine; and of an all-electric vehicle, also having a plug to connect to the

electrical grid. PHEVs have a much larger all-electric range as compared to conventional

gasoline-electric hybrids, and also eliminate the "range anxiety" associated with all-

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electric vehicles, because the combustion engine works as a backup when the batteries are

depleted.

Plug-in hybrid vehicles (PHEV) present a cleaner alternative to traditional vehicles, as

they use less oil and have lower emissions. PHEVs also use less oil than standard hybrid

electric vehicles (HEV), and at first glance seem to have lower emissions than HEVs.

PHEV with a range of 40 miles would have approximately half the emissions of a HEV if

it were powered by a carbon-free energy source, but would have higher emissions if 50%

of its electric power was generated by coal.

The Chevrolet Volt is a plug-in hybrid able to run in all-electric mode up to 35 miles.

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Chapter-7

ENVIRONMENTAL ISSUES CONCERNED WITH HEV

7.1 ENVIRONMENTAL ISSUES

Since the dawn of the modern era, consumption and distribution of energy has quickly

become mankind’s highest priority. However, the continued apathetic attitude that was

initially taken toward energy and its side effects can no longer be used. A new more

environmentally friendly source of energy has to be utilized in order to fulfil our own

needs otherwise we self-destruction while relying on non-renewable oil based methods. In

the last few decades two new technologies have emerged; the development and

implementation of Hybrid Electric Vehicles (HEVs) and more recently the Plug-in

Hybrid Electric Vehicles (PHEVs). These emerging technologies may make it possible

for the United States to adapt these technologies on a larger scale to reduce harmful

emissions and cut our dependence on foreign oil dramatically. However, the future of the

technologies will heavily depend on the everyday American consumer’s willingness to

forgo the ‘tried and true’ combustion engine for the infantile technologies of the HEV and

PHEV. With the introduction and continued popularity of HEVs and as well as the recent

hype over the PHEVs, the future of transportation in the United States is on the brink of

change. This project has objectives relevant to the aforementioned HEVs and PHEVs.

First, verify if independence of foreign oil is truly a possibility and how to accomplish

this feat. Second, identify the major motivators for the American consumers who

purchase these vehicles and how that can be used to increase the sales of HEVs and

PHEVs respectively. The third and last objective is to determine the future impact of the

all electric vehicle (EV).Earlier civilizations relied on a number of power sources such as

water to turn wheels, to run mills, fire to heat water and create steam, or windmills to turn

grinding stones. Since roughly the 17th century various forms of oil have been used, such

as kerosene, as fuel for lanterns. Even into the 18th, 19th, and early 20th centuries whales

were hunted for their blubber which could be converted into oil among other things. In

the more recent years with the invention of the combustion engine, which has not only

increased the shear amount of oil consumed annually but also drastically augmented our

dependence upon it in our daily lives. Our oil ‘addiction’ has lead us to the realization

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that our usage has its limits, not only does the environment suffer adverse effects because

of its use but our society is so dependent upon that if it were suddenly removed, most of

modern society would cease to function properly if it all. Without a reasonable alternative

this fate is all too possible and this has caused huge concerns over how, on a large scale,

we can change our consumption habits and create a cleaner energy for our use. Hybrid

cars have come a long way in the past 20 years, but most people are unaware they have

been around since the mid 1800s. The early electric vehicles at the turn of the 20th century

were expensive, problematic and not very powerful. Given certain weather conditions or

too steep a hill the electric vehicle of yesteryear was simply unable to perform up to our

expectations. With the introduction of the Ford Model T, a revolution in vehicles was

made. The Model T was cheaper and more powerful and was made relatively simplistic,

it also ran on a then abundant source of gasoline, and the United States could meet its

own internal demand enough so that it actually exported its excess to European countries

such as France and Britain. Ultimately, the Model T made the early EVs defunct and as

such fell off the radar until events like the 1973 oil crisis and 1979 energy crisis where the

electric technologies were eventually reconsidered. The first electric car is claimed to

have been built between 1832 and 1893 by Robert Anderson of Scotland. From then until

the late 1800s, when they became efficient enough to use as taxi cabs in England, the cars

were heavy, slow and impractical. Modern batteries development in the early 1900s

pushed the development of more efficient, reliable, and practical electric cars in that

period. The Hybrid came about in 1900 in Belgium, when a small gasoline engine was

paired with an electric motor. During normal operation the electric motor charged

onboard batteries, but during acceleration and uphill stints the electric motor provided a

boost to the 3.5 horsepower motor. In 1905 H Piper patented the first hybrid in America.

In 1910 a hybrid truck was manufactured in Pennsylvania, which used a 4 cylinder to

power a generator and an electric motor. 1916 saw the production of hybrid cars claiming

35 mph and 48 mpg, however this also saw the end of the electric car era due to the

advances in combustion engine technology. Until the mid to late 1960s, there is little

commercial advance in hybrid or electric cars. As early as the mid 1960s congress

recognized the importance of reducing emissions to improve air quality, and that the use

of electric cars was a possible way to achieve this. In the late 60s and early 70s the oil

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embargo sparked a renewed interest in hybrid and electric vehicles. A few hybrids were

released by major manufacturers, but most were underpowered and small. More

importantly, three scientists patented the first modern hybrid system in 1971, much of

which closely resemble the hybrids of today. The next big push from congress come s

with the 1976 Electric and Hybrid Vehicle Research, Development, and Demonstration

Act which encouraged the commercial improvement of electric motors and other hybrid

components. The research lead toward new developments and new vehicle released in the

United States, including all electrics from GM and Honda, even including an electric

truck, the Chevrolet S-10. These vehicles reached a niche group, but still did not receive

the sales numbers to be feasible. This all changed with the release of the Toyota Prius in

Japan in 1997. With 18000 sold in the first year it becomes the first economically feasible

hybrid produced. With its import to the united stated in 2000 and the release of Hondas

Insight to the US in 1999 the hybrid age had finally arrived. However, PHEVs and HEVs

are not without limitations, which are mainly caused by the current state of battery

technology. With future research and development into creating improvements on battery

technology many of the limitations will be greatly reduced if not expunged completely.

We have come a long way since the nickel and lead batteries of the 1960s, more recently

the Nickel Metal Hydride and Lithium Ion battery technologies have been developed and

successfully implemented. Today’s HEVs are a far cry from the small four horse power

models of the 1800s, modern HEVs include the same power, acceleration, comfort, and

price of their counterpart conventional cars (CVs), but can reach upwards of 50 miles per

gallon depending on the model. The importance of this project is not simply limited

toward the contemporary state of the automotive industry. It is also a generalized

overview of what to expect in the near future concerning the status of the global

automotive market and the respective technologies of which it encompasses. Valuable

insight given into possible implications of using the aforementioned technologies and

how they may affect the US and its ability to reach its energy goals all while becoming

both more energy independent and environmentally conscious. Projections for the future

give an overall view of what is to come, including future vehicles available for purchase,

their collective impact on the populace, and how that technology can be built upon and

advanced. It is essentially a forecast of the automotive industry from both a national and

global level. Based on the examination of information and projection from qualified data

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sources, it gives as full as possible understanding to the reader of where, when, and how

the automotive industry is now and in the foreseeable future.

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Chapter-8

WORKING OF HYBRID ELECTRIC VEHICLE

8.1 STARTING AND LOW SPEED PROCESS

8.1.1 Starting

When hybrid electric vehicle is initially started the battery typically powers all the

accessories of vehicle. The gasoline engine only starts if battery needs to be

charged or the accessories require more power than available from the battery.

8.1.2 Low speed process

For initial acceleration and slow-speed driving, as well as reverse, the electric

motor uses electricity from the battery to power the vehicle. If the battery needs to

be recharged, the generator starts the engine and converts energy from engine into

electricity, which is stored in the battery.

Fig. 8.1 Starting and low speed process of HEV

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8.2 CRUISING

To run the vehicle at the speed of above mid range for long period ( Long drive ).

At the time of cruising both internal combustion engine and electric motor are used to

propel the vehicle. The gasoline engine provide the power to the electric vehicle directly

and to the electric motor via the generator.

The generator also convert the energy from internal combustion engine into electricity

and send it to battery for storage.

Fig.. 8.2 Cruising process of HEV

8.3 PASSING

To pass or overtake any other vehicle.

During heavy accelerating or when additional power is needed , the gasoline engine and

electric motor are both used to propel the vehicle.

Additional energy from the battery may be used to power the vehicle.

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.Fig. 8.3 Passing process of HEV

8.4 BRAKING

Regenerative braking converts otherwise wastage energy from braking into electricity and

store it in the battery. In regenerative braking the electric motor is reversed so that,

instead of using electricity to turns the wheels, the rotating wheels turns the motor and

create electricity. Using energy from the wheels to turn the motor slows the vehicle down.

When decelerating, the braking system captures energy and stores it in the battery or

other device for later use, helping to keep batteries charged.

In motor case “Eb = V - IaRa“ Generally Eb < V

Here, Eb = Back emf of motor

V = Terminal voltage/Load side voltage

Ia = Armature current and

Ra = Armature resistance

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But in regenerative braking system Eb > V, means the load supplies the power to

motor.

If additional stopping power is required we apply friction bakes like disk brakes to

stop the vehicle.

Fig. 8.3 Braking process of HEV

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Chapter-9

PREDECESSORS OF CURRENT TECHNOLOGY IN HEV

9.1 CURRENT TECHNOLOGY

A more recent working prototype of the HEV was built by Victor Wouk (one of the

scientists involved with the Henney Kilowatt, the first transistor-based electric car).

Wouk's work with HEVs in the 1960s and 1970s earned him the title as the "Godfather of

the Hybrid". Wouk installed a prototype hybrid drive-strain (with a 16 kilowatts (21 hp)

electric motor) into a 1972 Buick Skylark provided by GM for the 1970 Federal Clean

Car Incentive Program, but the program was stopped by the United States Environmental

Protection Agency (EPA) in 1976 while Eric Stork, the head of the EPA's vehicle

emissions control program at the time, was accused of a prejudicial coverup.

The regenerative braking system, the core design concept of most production HEVs, was

developed by electrical engineer David Arthurs around 1978, using off-the shelf

components and an Opel GT. However the voltage controller to link the batteries, motor

(a jet-engine starter motor), and DC generator was Arthurs'. The vehicle exhibited

75 miles per US gallon (3.1 L/100 km; 90 mpg-imp) fuel efficiency, and plans for it (as

well as somewhat updated versions) are still available through the Mother Earth News

web site. The Mother Earth News' own 1980 version claimed nearly 84 miles per US

gallon (2.8 L/100 km; 101 mpg-imp).

In 1989, Audi produced its first iteration of the Audi Duo (the Audi C3 100 Avant Duo)

experimental vehicle, a plug-in parallel hybrid based on the Audi 100 Avant quattro. This

car had a 9.4 kilowatts (12.8 PS; 12.6 bhp) Siemens electric motor which drove the rear

road-wheels. A trunk-mounted nickel-cadmium battery supplied energy to the motor that

drove the rear wheels. The vehicle's front road-wheels were powered by a 2.3 litre five-

cylinder petrol engine with an output of 100 kilowatts (136 PS; 134 bhp). The intent was

to produce a vehicle which could operate on the engine in the country, and electric mode

in the city. Mode of operation could be selected by the driver. Just ten vehicles are

believed to have been made; one drawback was that due to the extra weight of the electric

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drive, the vehicles were less efficient when running on their engines alone than standard

Audi 100s with the same engine.

Two years later, Audi, unveiled the second duo generation, the Audi 100 Duo -likewise

based on the Audi 100 Avant quattro. Once again, this featured an electric motor, a 21.3

kilowatts (29.0 PS; 28.6 bhp) three-phase machine, driving the rear road-wheels. This

time, however, the rear wheels were additionally powered via the Torsen centre

differential from the main engine compartment, which housed a 2.0 litre four-cylinder

engine.[citation needed]

In 1992, Volvo ECC was developed by Volvo. The Volvo ECC was built on the Volvo

850 platform. In contrast to most production hybrids, which use a gasoline piston engine

to provide additional acceleration and to recharge the battery storage, the Volvo ECC

used a gas turbine engine to drive the generator for recharging.

The Clinton administration initiated the Partnership for a New Generation of Vehicles

(PNGV) program on 29 September 1993, that involved Chrysler, Ford, General Motors,

USCAR, the DoE, and other various governmental agencies to engineer the next efficient

and clean vehicle. The United States National Research Council (USNRC) cited

automakers' moves to produce HEVs as evidence that technologies developed under

PNGV were being rapidly adopted on production lines, as called for under Goal 2. Based

on information received from automakers, NRC reviewers questioned whether the "Big

Three" would be able to move from the concept phase to cost effective, pre-production

prototype vehicles by 2004, as set out in Goal 3. The program was replaced by the

hydrogen-focused FreedomCAR initiative by the George W. Bush administration in 2001,

an initiative to fund research too risky for the private sector to engage in, with the long-

term goal of developing effectively carbon emission- and petroleum-free vehicles.

1998 saw the Esparante GTR-Q9 became the first Petrol-Electric Hybrid to race at Le

Mans, although the car failed to qualify for the main event. The car managed to finished

second in class at Petit Le Mans the same year.

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ADVANTAGES AND DISADVANTAGES OF HEV

10.1 ADVANTAGES

Hybrid cars emit up to 90% less toxic emissions and half as much greenhouse-this

causes carbon dioxide as an average car(therefore drivers would not have to worry

about polluting the environment).

Hybrids can run on electricity or gas.

Less fuel consumption. Current HEVs reduce petroleum consumption under

certain circumstances, compared to otherwise similar conventional vehicles,

primarily by using three mechanisms:

1. Reducing wasted energy during idle/low output, generally by turning the

ICE off

2. Recapturing waste energy (i.e. regenerative braking)

3. Reducing the size and power of the ICE, and hence inefficiencies from

under-utilization, by using the added power from the electric motor to

compensate for the loss in peak power output from the smaller ICE.

Any combination of these three primary hybrid advantages may be used in

different vehicles to realize different fuel usage, power, emissions, weight and

cost profiles. The ICE in an HEV can be smaller, lighter, and more efficient than

the one in a conventional vehicle, because the combustion engine can be sized for

slightly above average power demand rather than peak power demand. The drive

system in a vehicle is required to operate over a range of speed and power, but an

ICE's highest efficiency is in a narrow range of operation, making conventional

vehicles inefficient. On the contrary, in most HEV designs, the ICE operates

closer to its range of highest efficiency more frequently. The power curve of

electric motors is better suited to variable speeds and can provide substantially

greater torque at low speeds compared with internal-combustion engines. The

greater fuel economy of HEVs has implication for reduced petroleum

consumption and vehicle air pollution emissions worldwide.

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The battery pack of a hybrid vehicle never needs to be charged from an external

source. It’s charged by ICE and by motor from braking system.

Hybrids have smaller engines, therefore they tend to weight less than non-

hybrids(but this can lead to problems in the future). Since hybrid cars can run on

alternative fuels, this allows us to decrease our dependency on fossil fuel and

enables us to increase fuel options.(hybrids reduce fuel costs).

A person who purchases a hybrid car is entitled to a federal tax deduction.

10.2 DISADVANTAGES

Hybrids are more expensive than non-hybrids. The cost of HEV is more because

it’s using more parts than non-HEV and these all are costly.

It require more maintenance. It’s using more parts so all require more

maintenance.

It has low towing capacity. It’s engine size is small so it’s don’t able to import and

export more things.

The parts that make up the hybrid car are more expensive and are more difficult to

acquire for one’s car.

Since a hybrid is electrical, Water cannot be used to put out a fire that starts in the

hybrid.

Hybrids(in regards to a car accident)have a much higher risk of

exploding(depending on the impact of the vehicle)because it has a combination of

gasoline and ethanol(which are both highly flammable).

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Chapter-11

MODERN HYBRIDS PRODUCTION

11.1 MODERN HYBRID PRODUCTION

Automotive hybrid technology became widespread beginning in the late 1990s. The first

mass-produced hybrid vehicle was the Toyota Prius, launched in Japan in 1997, and

followed by the Honda Insight, launched in 1999 in the United States and Japan. The

Prius was launched in Europe, North America and the rest of the world in 2000. The first

generation Prius sedan has an estimated fuel economy of 52 miles per US gallon

(4.5 L/100 km; 62 mpg-imp) in the city and 45 miles per US gallon (5.2 L/100 km;

54 mpg-imp) in highway driving. The two-door first generation Insight was estimated at

61 miles per US gallon (3.9 L/100 km; 73 mpg-imp) miles per gallon in city driving and

68 miles per US gallon (3.5 L/100 km; 82 mpg-imp) on the highway.

The Toyota Prius sold 300 units in 1997, 19,500 in 2000, and cumulative worldwide Prius

sales reached the 1 million mark in April 2008. By early 2010, the Prius global

cumulative sales were estimated at 1.6 million units. Toyota launched a second generation

Prius in 2004 and a third in 2009. The 2010 Prius has an estimated U.S. Environmental

Protection Agency combined fuel economy cycle of 50 miles per US gallon

(4.7 L/100 km; 60 mpg-imp).

The Audi Duo III was introduced in 1997, based on the Audi B5 A4 Avant, and was the

only Duo to ever make it into series production. The Duo III used the 1.9 litre

Turbocharged Direct Injection (TDI) diesel engine, which was coupled with an 21

kilowatts (29 PS; 28 bhp) electric motor. Unfortunately due to low demand for this hybrid

because of its high price, only about sixty Audi Duos were produced. Until the release of

the Audi Q7 Hybrid in 2008, the Duo was the only European hybrid ever put into

production. The Honda Civic Hybrid was introduced in February 2002 as a 2003 model,

based on the seventh generation Civic. The 2003 Civic Hybrid appears identical to the

non-hybrid version, but delivers 50 miles per US gallon (4.7 L/100 km; 60 mpg-imp), a

40 percent increase compared to a conventional Civic LX sedan. Along with the

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conventional Civic, it received styling update for 2004. The redesigned 2004 Toyota Prius

(second generation) improved passenger room, cargo area, and power output, while

increasing energy efficiency and reducing emissions. The Honda Insight first generation

stopped being produced after 2006 and has a devoted base of owners. A second

generation Insight was launched in 2010. In 2004, Honda also released a hybrid version

of the Accord but discontinued it in 2007 citing disappointing sales.

The Ford Escape Hybrid, the first hybrid electric sport utility vehicle (SUV) was released

in 2005. Toyota and Ford entered into a licensing agreement in March 2004 allowing

Ford to use 20 patents[citation needed] from Toyota related to hybrid technology,

although Ford's engine was independently designed and built.[citation needed] In

exchange for the hybrid licenses, Ford licensed patents involving their European diesel

engines to Toyota.[citation needed] Toyota announced calendar year 2005 hybrid electric

versions of the Toyota Highlander Hybrid and Lexus RX 400h with 4WD-i, which uses a

rear electric motor to power the rear wheels negating the need for a transfer case.

In 2006, General Motors Saturn Division began to market a mild parallel hybrids in the

form of the 2007 Saturn Vue Green Line which utilized GM's Belted Alternator/Starter

(BAS Hybrid) System combined with a 2.4 litre L4 engine and a FWD automatic

transmission. The same hybrid power-strain was also used to power the 2008 Saturn Aura

Greenline and Malibu Hybrid models. As of December 2009, only the BAS equipped

Malibu is still in (limited) production.

In 2007, Lexus released a hybrid electric version of their GS sport sedan, the GS 450h,

with a power output of 335 bhp. The 2007 Camry Hybrid became available in Summer

2006 in the United States and Canada. Nissan launched the Altima Hybrid with

technology licensed by Toyota in 2007.

Commencing in the fall of 2007 General Motors began to market their 2008 Two-Mode

Hybrid models of their GMT900 based Chevrolet Tahoe and GMC Yukon SUVs, closely

followed by the 2009 Cadillac Escalade Hybrid version. For the 2009 model year,

General Motors released the same technology in their half-ton pickup truck models, the

2009 Chevrolet Silverado and GMC Sierra Two-Mode Hybrid models.

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The Ford Fusion Hybrid officially debuted at the Greater Los Angeles Auto Show in

November 2008, and was launched to the U.S. market in March 2009, together with the

second generation Honda Insight and the Mercury Milan Hybrid.

Fig. 11.1 1997 Toyota Prius (first generation)

Fig. 11.2 2000 Honda Insight (first generation)

Fig. 11.3 2010 Honda Insight (second generation)

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Fig. 11.3 2010 Ford Fusion Hybrid

CONCLUSION

Means a hybrid vehicle is a vehicle that uses two or more distinct power sources to move

the vehicle. The term most commonly refers to hybrid electric vehicles (HEVs), which

combine an internal combustion engine and one or more electric motors.

Modern HEVs make use of efficiency-improving technologies such as regenerative

braking, which converts the vehicle's kinetic energy into electric energy to charge the

battery, rather than wasting it as heat energy as conventional brakes do. Some varieties of

HEVs use their internal combustion engine to generate electricity by spinning an

electrical generator (this combination is known as a motor-generator), to either recharge

their batteries or to directly power the electric drive motors. Many HEVs reduce idle

emissions by shutting down the ICE at idle and restarting it when needed; this is known

as a start-stop system. A hybrid-electric produces less emissions from its ICE than a

comparably-sized gasoline car, since an HEV's gasoline engine is usually smaller than a

comparably-sized pure gasoline-burning vehicle (natural gas and propane fuels produce

lower emissions) and if not used to directly drive the car, can be geared to run at

maximum efficiency, further improving fuel economy.

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REFERENCES

1. Hybrid electric vehicle - Wikipedia, the free encyclopedia

http://en.wikipedia.org/wiki/Hybrid_electric_vehicle

2. Ford – Escape  Hybrid – SUV – 35mpg – price unannounced

http://www.fordvehicles.com/escapehybrid/home/index.asp?bhcp=1

3. Toyota – Prius – $20,810 – 55mpg –

http://www.toyota.com/prius/

4. How Hybrids Work - Fuel Economy

www.fueleconomy.gov/feg/ hybrid tech.shtml

5. Hybrid-electric vehicle financial definition of Hybrid-electric vehicle

financial-dictionary.thefreedictionary.com/ Hybrid - electric + vehicle

6. Electric Car

http://www.hybridcars.com/electric-car

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