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    ABSTRACT

    In an era where energy conservation has become the latest topic of discussion not

    only among the erudite but also among the ordinary responsible denizens, fuel efficiency

    along with minimum pollution has become the benchmark for any new automobile.

    And in the same context Hybrid Electric Vehicle come as the latest addition. By

    the name itself it can be inferred that a Hybrid Electric Vehicle is an improvisation to the

    traditional gasoline engine run car combined with the power of an electric motor.

    The seminar on the above topic intends to bring to notice the concepts associated

    with the hybrid technology through the following topics components and constituents,

    need, efficiency, performance, etc.

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    CONTENTS

    CHAPTERS

    INTRODUCTION

    WHAT IS A HYBRID VEHICLE?

    HYBRID STRUCTURE

    HYBRID COMPONENT.

    INTERNAL COMBUSTION ENGINE.

    ELECTRIC MOTOR

    ALTERNATOR

    EVOLUTION OF HYBRID

    HYBRID PERFORMANCE

    HYBRID EFFICIENCY

    WHATS AVILABLE NOW?

    HYBRID MILEAGE TIPS

    CONCLUSION

    REFERENCES

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    INTRODUCTION

    Have you pulled your car up to the gas pump lately and been shocked by the high

    price of gasoline? As the pump clicked past $20 or $30, maybe you thought about trading

    in that SUV for something that gets better mileage. Or maybe you are worried that your

    car is contributing to the greenhouse effect. Or maybe you just want to have the coolest

    car on the block.

    Currently, there is a solution for all this problems; its the hybrid electric

    vehicle. The vehicle is lighter and roomier than a purely electric vehicle, because there is

    less need to carry as many heavy batteries. The internal combustion engine in hybrid-

    electric is much smaller and lighter and more efficient than the engine in a conventional

    vehicle. In fact, most automobile manufacturers have announced plans to manufacture

    their own hybrid versions.

    How does a hybrid car work? What goes on under the hood to give you 20 or 30

    more miles per gallon than the standard automobile? And does it pollute less just because

    it gets better gas mileage. In this seminar we will study how this amazing technology

    works and also discuss about TOYOTA & HONDA hybrid cars.

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    WHAT IS A HYBRID ELECTRIC VEHICLE"?

    Any vehicle is hybrid when it combines two or more sources of power. In fact,

    many people have probably owned a hybrid vehicle at some point. For example, a mo-

    ped (a motorized pedal bike) is a type of hybrid because it combines the power of a

    gasoline engine with the pedal power of its rider.

    Hybrid electric vehicles are all around us. Most of the locomotives we see pulling

    trains are diesel-electric hybrids. Cities like Seattle have diesel-electric buses -- these

    can draw electric power from overhead wires or run on diesel when they are away from

    the wires. Giant mining trucks are often diesel-electric hybrids. Submarines are also

    hybrid vehicles -- some are nuclear-electric and some are diesel-electric. Any vehicle

    that combines two or more sources of power that can directly or indirectly provide

    propulsion power is a hybrid.

    The most commonly used hybrid is gasoline-electric hybrid car whichis just a

    cross between a gasoline-powered car and an electric car. A gasoline-electric hybrid car

    or hybrid electric vehicle is a vehicle which relies not only on batteries but also on an

    internal combustion engine which drives a generator to provide the electricity and may

    also drive a wheel. In hybrid electric vehicle the engine is the final source of the energy

    used to power the car. All electric cars use batteries charged by an external source,

    leading to the problem of range which is being solved in hybrid electric vehicle.

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    HYBRID STRUCTURE

    You can combine the two power sources found in a hybrid car in different ways.

    One way, known as a parallel hybrid, has a fuel tank, which supplies gasoline to the

    engine. But it also has a set of batteries that supplies power to an electric motor. Both the

    engine and the electric motor can turn the transmission at the same time, and the

    transmission then turns the wheels.

    Figure 1. Parallel hybrid car

    Figure 1 shows a typical parallel hybrid. We'll notice that the fuel tank and gas

    engine connect to the transmission. The batteries and electric motor also connect to the

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    transmission independently. As a result, in a parallel hybrid, both the electric motor and

    the gas engine can provide propulsion power.

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    Figure 2. Series hybrid car

    Another way of combining the power sources found in a hybrid car is by series

    hybrid. In a series hybrid (Figure 2 above) the gasoline engine turns a generator, and the

    generator can either charge the batteries or power an electric motor that drives the

    transmission. Thus, the gasoline engine never directly powers the vehicle. Take a look at

    the diagram of the series hybrid, starting with the fuel tank, and you'll see that all of the

    components form a line that eventually connects with the transmission.

    HYBRID COMPONENTS

    Components used in hybrid electric vehicles are given below:

    Gasoline engine - The hybrid car has a gasoline engine much like the one you will

    find on most cars. However, the engine on a hybrid will be smaller and lighter, and is

    more efficient than the engine in a conventional vehicle, because the engine runs at a

    relatively constant speed, and does not need to provide direct power for acceleration,

    which is the biggest reason for large engines. Use advanced technologies to reduce

    emissions.

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    Fuel tank- Thefuel tankin a hybrid is the energy storage device for the gasoline

    engine. Gasoline has a much higher energy density than batteries do. For example, it

    takes about 1,000 pounds of batteries to store as much energy as 1 gallon (7 pounds) of

    gasoline.

    Electric motor - The electric motoron a hybrid car is very sophisticated. Electric

    motor used in hybrid cars are usually dc series motor since its versatile and ease with

    which a variety of speed-torque characteristics can be obtained, and wide range of speed

    control is also possible in this. Advanced electronics allow it to act as a motor as well as

    a generator. For example, when it needs to, it can draw energy from the batteries to

    accelerate the car. But acting as a generator, it can slow the car down and return energy

    to the batteries.

    Generator - The generator is similar to an electric motor, but it acts only to

    produce electrical power. It is used mostly on series hybrids. Generator used in hybrid

    electric vehicle is alternator since cooling is easy and hence maximum output and also

    the output/weight ratio is higher than that of the DC generator.

    Power split device The power split device is a clever gearbox that hooks the

    internal combustion engine and D.C.motor together. The power split device helps the

    vehicle to accelerate to a speed of about 15km/hr before switching on the gasoline

    engine. The engine starts only after the vehicle attains a certain speed. Once the engine

    starts it operates on a narrow speed band. The power split device allows the engine to

    stay in its most efficient load and speed range most of the time.

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    Batteries - The batteries in a hybrid car are the energy storage device for the

    electric motor. Unlike the gasoline in the fuel tank, which can only power the gasoline

    engine, the

    electric motor on a hybrid car can put energy into the batteries as well as draw energy

    from them. The batteries used in HEV is Ni-Cd cells since its lighter than the lead acid

    cells and its also mechanically strong and can stand very rough use.

    Transmission - The transmission on a hybrid car performs the same basic function

    as the transmission on a conventional car. Some hybrids, like the Honda Insight, have

    conventional transmissions. Others, like the Toyota Prius, have radically different ones,

    which well talk about later.

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    INTERNAL COMBUSTION ENGINE

    The figure gives the internal view of IC

    engine. The different components in the IC engine are given below.

    Cylinder

    The core of the engine is the cylinder. The piston moves up and down inside the cylinder.

    The engine described here has one cylinder. That is typical of most lawn mowers, but

    most cars have more than one cylinder (four, six and eight cylinders are common). In a

    multi-cylinder engine the cylinders usually are arranged in one of three ways: inline, V

    or flat. Different configurations have different smoothness, manufacturing-cost and

    shape characteristics that make them more suitable in some vehicles.

    Sparkplug

    The spark plug supplies the spark that ignites the air/fuel mixture so that combustion can

    occur. The spark must happen at just the right moment for things to work properly.

    Valves

    The intake and exhaust valves open at the proper time to let in air and fuel and to let out

    Figure 3

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    exhaust. Note that both valves are closed during compression and combustion so that the

    combustion chamber is sealed.

    Piston

    A piston is a cylindrical piece of metal that moves up and down inside the cylinder.

    Pistonrings

    Piston rings provide a sliding seal between the outer edge of the piston and the inner edge

    of the cylinder. The rings serve two purposes:

    They prevent the fuel/air mixture and exhaust in the combustion chamber from

    leaking into the sump during compression and combustion.

    They keep oil in the sump from leaking into the combustion area, where it would be

    burned and lost.

    Most cars that "burn oil" and have to have a quart added every 1,000 miles are burning it

    because the engine is old and the rings no longer seal things properly.

    Combustionchamber

    The combustion chamber is the area where compression and combustion take place. As

    the piston moves up and down, you can see that the size of the combustion chamber

    changes. It has some maximum volume as well as a minimum volume. The difference

    between the maximum and minimum is called the displacement and is measured in liters

    or CCs (Cubic Centimeters, where 1,000 cubic centimeters equals a liter). So if you have

    a 4-cylinder engine and each cylinder displaces half a liter, then the entire engine is a "2.0

    liter engine." If each cylinder displaces half a liter and there are six cylinders arranged in

    a V configuration, you have a "3.0 liter V-6." s. A cylinder that displaces half a liter can

    hold twice as much fuel/air mixture as a cylinder that displaces a quarter of a liter, and

    therefore you would expect about twice as much power from the larger cylinder (if

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    everything else is equal). So a 2.0 liter engine is roughly half as powerful as a 4.0 liter

    engine. You can get more displacement either by increasing the number of cylinders or

    by making the combustion chambers of all the cylinders bigger (or both).

    Connectingrod

    Connecting rod connects the piston to the crankshaft. It can rotate at both ends so that

    angle can change as the piston moves and the crankshaft rotates.

    Crankshaft

    The crank shaft turns the pistons up and down motion into circular motion just like a

    crank on a jack-in-the-box does.

    Sump

    The sump surrounds the crankshaft. It contains some amount of oil, which collects in the

    bottom of the sump (the oil pan).

    SMALLER ENGINES ARE MORE EFFICIENT

    Most cars require a relatively big engine to produce enough power to

    accelerate the car quickly. In a small engine, however, the efficiency can be improved by

    using smaller, lighter parts, by reducing the number of cylinders and by operating the

    engine closer to its maximum load.

    There are several reasons why smaller engine are more efficient than big ones:

    The big engine is heavier than the small engine, so the car uses extra energy every

    time it accelerates or drives up a hill.

    The pistons and other internal components are heavier, requiring more energy each

    time they go up and down in the cylinder.

    The displacement of the cylinders is larger, so more fuel is required by each

    cylinder.

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    Bigger engines usually have more cylinders, and each cylinder uses fuel every time

    the engine fires, even if the car isn't moving.

    This explains why two of the same model cars with different engines can get

    different mileage. If both cars are driving along the freeway at the same speed, the one

    with the smaller engine uses less energy. Both engines have to output the same amount of

    power to drive the car, but the small engine uses less power to drive itself

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    ELECTRIC MOTOR

    An electric motor is all about magnets and magnetism: A motor

    uses magnets to create motion. We know the fundamental law of all magnets: Opposites

    attract and likes repel. So if you have two bar magnets with their ends marked "north"

    and "south," then the north end of one magnet will attract the south end of the other. On

    the other hand, the north end of one magnet will repel the north end of the other (and

    similarly, south will repel south). Inside an electric motor, these attracting and repelling

    forces create rotational motion.

    DC series motor used in hybrid electric vehicle is a versatile and flexible

    machine. It can satisfy the demands of load recurring high starting, accelerating and

    retarding torques. A DC machine is also easily adaptable for drives with a wide range of

    speed control and fast reversals. In the diagram shown below we can see two magnets in

    the motor: The armature (or rotor) is an electromagnet, while the field magnet is a

    permanent magnet (the field magnet could be an electromagnet as well, but in most small

    motors it isn't in order to save power). Different parts used in a simple DC motor are as

    shown in the diagram below:

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    Parts of an electric motor

    Armature or rotor

    Stator

    Commutator

    Brushes

    Field magnet

    The magnetic circuit of a DC consists of the armature magnetic material

    (core), the air-gap, field poles and yoke. The yoke of a DC machine is a annular ring to

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    the middle of which is bolted field poles and the interlopes. The interlopes or

    commutation poles are narrow poles fixed to the yoke, midway between the main field

    poles. The use of an electric field winding, which supplies electric energy to establish a

    magnetic field in the magnetic circuit , result in the great diversity and a variety of

    performance characteristics. The armature winding is connected to the external power

    source through a commutator brush system, which is a mechanical rectifying (switching)

    device for converting the alternating currents and induced emf of the armature to the DC

    form.

    The cylindrical-rotor or armature of a machine is mounted on a shaft, which is supported

    on the bearing. One or both ends of the shaft act as input or output terminal of the

    machine and would be coupled mechanically to a load (motoring machine) or to a prime-

    mover (generating machine).Usually parallel-sided axial slots (evenly spaced normally)

    are used on the rotor (armature winding) surface. The magnetic material between the

    slots is the teeth. The slot cross-section influences significantly the performance

    characteristics of the machines and parameters such as armature coil inductance,

    magnetic saturation in the teeth, eddy-current loss in the stator poles and the cost and

    complexity of laying armature winding.

    BRAKING OF DC SERIES MOTOR:

    Controlled slowing or stopping of a motor and its driven load is as important as

    starting in many applications. Braking methods based on friction , electromechanical

    action, eddy current, etc are independent of the motor but sometimes electric braking is

    better justified owing to its greater economy and absence of brake wears. The DC motor

    is still widely used for traction purpose. One of the main reasons for this is its excellent

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    braking characteristics and ability of smooth transition from the motor to the generator

    mode and vice versa. During the braking period, the motor is operated as a generator and

    the kinetic or gravitational potential energy is dissipated in resistors or returned to the

    supply.

    ALTERNATOR

    An electric generator is a device that converts mechanical energy into electrical energy

    .it produce alternating currents. It works on the principle of electromagnetic induction

    which states that when a coil is rotated about an axis perpendicular to the direction of

    uniform magnetic field, an induced emf is produced across it. Alternator requires a

    magnetic field as well as a rotating coil. The coil is wound in a special manner know as

    armature. To produce current either this armature or magnetic field can be rotated. The

    only thing is that it should cut the magnetic field. Usually the armature winding is

    stationary (called stator) and the field winding is rotating (know as rotor). An alternator

    consist of

    Frame or housing

    Stator

    Rotor

    Slip ring and brushes

    Frame or housing: Frame is an important part of alternator. This encloses the entire

    alternator assembly and is made of aluminum. Frame is made up of two parts. The front

    part of the frame has ball bearing, and the rear part contains roller bearing for supporting

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    the rotor. The front part usually known as drive end housing and rear part is known as

    brush end housing.

    Stator: The armature is an iron ring framed of laminated special magnetic iron or steel

    alloy having slots on its inner periphery to accommodate armature conductors and is

    known as stator. Stator is the stationary part of the alternator. Field rotates between the

    stator so that the fluxing of the rotating field cuts the core of the stator, which includes

    the required emf.

    Rotor: It consists of an iron core around the rotor shaft. Many turns of the copper wire

    coated with varnish are wound around the core. On both sides of the rotor winding are

    the

    thick metal plates bent over the winding with triangular fingers called poles. These metal

    plates are called pole pieces. The pole pieces are placed interfacing each other so that

    when the current flows through the winding, these poles pieces acquire opposite polarity.

    This will result in alternating north and south magnetic poles on the pole fingers. This

    creates magnetic fields between the alternating pole fingers.

    Slip rings and brushes: Due to the cutting of the magnetic field, an emf and hence a

    current is produced in the rotor winding. Since the coil is rotating, its not possible to take

    current from the coil using wires. But special arrangements are necessary for carrying

    current to outside. The current from the rotor winding is usually carried through the

    copper slip rings and the carbon brushes. As these brushes carry only the field current

    (2.5A), it has longer life.

    Why an alternator in used in a hybrid electric vehicle?

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    In conventional cars, the kinetic energy developed during running is wasted as heat

    energy while braking which waste a lot of energy as heat. Here the alternator converts the

    kinetic energy into useful electric energy, which can be stored in the batteries. The

    alternator is connected to the propeller shaft and rotates all the time. When braking is

    needed the field of the generator is charged using a rheostat. This produces a flux in the

    coils and the electricity is produced. The rheostat can be avoided by using electronic

    circuit, which can provide excellent variation in braking as needed. The alternator can

    also be employed at light loads when traveling at high speeds when the battery charge is

    low. The electric energy thus produced is sufficient to run the motor. This eliminates the

    need of external recharging. This contributes to the overall efficiency of the vehicle.

    EVOLUTION OF THE HYBRID

    The first hybrid electric car was engineered by Ferdinand Porsche in

    1928.since then, hobbyists have built such cars but no such cars can put into production

    until the waning year of the 20th century .However hybrid technology has been in use on

    railroad ever since 1930s, when the locomotives on early streamliners ran on gasoline-

    electric and diesel-electric systems at greater efficiencies than the stream engines of the

    days.

    Automotive hybrid technology became commercially successful in the 1990s when the

    Honda Insight and Toyota Prius became available these vehicles have a direct linkage

    from the internal combustion engine to the drive, so that the engine can provide

    acceleration power. Prototypes of plug-in hybrid cars, with large battery packs that can

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    be recharged from the power grid ,have been built in the U.S.,and one production PHEV,

    the Renault Kangoo,went on sale in France in 2003 ,and Daimler Chrysleris currently

    building a small number of PHEVs based on the Mercedes Sprinter

    The hybrid is a compromise. It attempts to significantly increase the mileage and reduce

    the emissions of a gas-powered car while overcoming the shortcomings of an electric car.

    The Problem with Gas-powered Cars

    To be useful for all, a car must meet certain minimum requirements.

    The car should be able to:

    Drive at least 300 miles (482 km) between re-fueling

    Be refueled quickly and easily

    Keep up with the other traffic on the road

    A gasoline car meets these requirements but produces a relatively large amount of

    pollution and generally gets poor gas mileage. An electric car, on the other hand,

    produces almost no pollution, but it can only go 50 to 100 miles (80 to 161 km) between

    charges. And the problem has been that it is very slow and inconvenient to recharge.

    A driver's desire for quick acceleration causes our cars to be much less efficient than

    they could be. You may have noticed that a car with a less powerful engine gets better

    gas mileage than an identical car with a more powerful engine. Just look at the window

    stickers on new cars at a dealership for a city and highway mpg comparison.

    The amazing thing is that most of what we require a car to do uses only a small

    percentage of its horsepower! When you are driving along the freeway at 60 mph (96.6

    kph), your car engine has to provide the power to do three things:

    Overcome the aerodynamic drag caused by pushing the car through the air

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    Overcome all of the friction in the car's components such as the tires,transmission,

    axles andbrakes

    Provide power for accessories like air conditioning,power steering and headlights

    For most cars, doing all this requires less than 20 horsepower! So, why do you need a car

    with 200 horsepower? So you can "floor it," which is the only time you use all that

    power. The rest of the time, you use considerably less power than you have available.

    HYBRID PERFORMANCE

    The key to a hybrid car is that the gasoline engine can be much smaller than the one in a

    conventional car and therefore more efficient. But how can this smaller engine provide

    the power your car needs to keep up with the more powerful cars on the road?

    Let's compare a car like the Chevy Camaro, with its big V-8 engine, to our hybrid car

    with its small gas engine and electric motor. The engine in the Camaro has more than

    enough power to handle any driving situation. The engine in the hybrid car is powerful

    enough to move the car along on the freeway, but when it needs to get the car moving in

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    a hurry, or go up a steep hill, it needs help. That "help" comes from the electric motor and

    battery -- this system steps in to provide the necessary extra power.

    The gas engine on a conventional car is sized for the peak power requirement (those few

    times when you floor the accelerator pedal). In fact, most drivers use the peak power of

    their engines less than one percent of the time. The hybrid car uses a much smaller

    engine, one that is sized closer to the average power requirement than to the peak power.

    HYBRID EFFICIENCY

    Besides a smaller, more efficient engine, today's hybrids use many other

    tricks to increase fuel efficiency. Some of those tricks will help any type of car get better

    mileage, and some only apply to a hybrid. To squeeze every last mile out of a gallon of

    gasoline, a hybrid car can:

    Recover energy and store it in the battery - Whenever you step on the brake

    pedal in your car, you are removing energy from the car. The faster a car is going, the

    more kinetic energy it has. The brakes of a car remove this energy and dissipate it in the

    form of heat. A hybrid car can capture some of this energy and store it in the battery to

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    use later. It does this by using "regenerative braking." That is, instead of just using the

    brakes to stop the car, the electric motor that drives the hybrid can also slow the car. In

    this mode, the electric motor acts as a generator and charges the batteries while the car is

    slowing down.

    Sometimes shut off the engine - A hybrid car does not need to rely on the gasoline

    engine all of the time because it has an alternate power source -- the electric motor and

    batteries. So the hybrid car can sometimes turn off the gasoline engine, for example when

    the vehicle is stopped at a red light.

    Use low-rolling resistance tires - The tires on most cars are optimized to give a

    smooth ride, minimize noise, and provide good traction in a variety of weather

    conditions. But they are rarely optimized for efficiency. In fact, the tires cause a

    surprising amount of drag while you are driving. Hybrid cars use special tires that are

    both stiffer and inflated to a higher pressure than conventional tires. The result is that

    they cause about half the drag of regular tires.

    Use advanced aerodynamics to reduce drag - When you are driving on the

    freeway, most of the work your engine does goes into pushing the car through the air.

    Figure 4. The frontal area

    profile of a small and large

    car

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    This force is known as aerodynamic drag. This drag force can be reduced in a variety of

    ways. One sure way is to reduce the frontal area of the car (Figure 5). Think of how a big

    SUV has to push a much greater area through the air than a tiny sports car.

    Reducing disturbances around objects that stick out from the car or eliminating them

    altogether can also help to improve the aerodynamics. For example, covers over the

    wheel housings smooth the airflow and reduce drag. And sometimes, mirrors are replaced

    with small cameras. This site provides more information on car aerodynamics.

    Use lightweight materials - Reducing the overall weight of a car is one easy way

    to increase the mileage. A lighter vehicle uses less energy each time you accelerate or

    drive up a hill. Composite materials like carbon fiber or lightweight metals like

    aluminum and magnesium can be used to reduce weight.

    WHAT'S AVAILABLE NOW?

    Two hybrid cars are now available in the world market -- the Honda Insight and

    the Toyota Prius Although both of these cars are hybrids, they are actually quite different

    in character. The Honda is about $18,000, and the Toyota about $20,000. Both cars have

    a gasoline engine, an electric motor and batteries, but that is where the similarities end.

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    The Honda Insight, which was introduced in early 2000 in the United States, is designed

    to get the best possible mileage. Honda used every trick in the book to make the car as

    efficient as it can be. The Insight is a small, lightweight two-seater with a tiny, high-

    efficiency gas engine.

    The Toyota Prius, which came out in Japan at the end of 1997, is designed

    to reduce emissions in urban areas. It meets California's super ultra low emissions

    vehicle (SULEV) standard. It is a four-door sedan that seats five, and the power train is

    capable of accelerating the vehicle to speeds up to 15 mph (24 kph) on electric power

    alone.

    Hybrid maintenance:

    Both the Honda and the Toyota have long warranties on the hybrid systems. The Insight

    has an eight-year/80,000-mile warranty on most of the power train, including batteries,

    and a three-year/36,000-mile warranty on the rest of the car. The Prius has an eight-

    year/100,000-mile warranty on the battery and hybrid systems and a three-year/36,000-

    mile warranty on everything else. The motors and batteries in these cars don't require any

    maintenance over the life of the vehicle. And the engine doesn't require any more

    maintenance than the one in any other car. And because both hybrids have regenerative

    braking, the brake pads may even last a little longer than those in most cars.

    HYBRID MILEAGE TIPS

    You can get the best mileage from a hybrid car by using the same kind of driving habits

    that give you better mileage in your gasoline-engine car:

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    Drive slower - The aerodynamic drag on the car increases dramatically the faster

    you drive. For example, the drag force at 70 mph (113 kph) is about double that at 50

    mph (81 kph). So, keeping your speed down can increase your mileage significantly.

    Maintain a constant speed - Each time you speed up the car you use energy, some

    of which is wasted when you slow the car down again. By maintaining a constant speed,

    you will make the most efficient use of your fuel.

    Avoid abrupt stops - When you stop your car, the electric motor in the hybrid acts

    like a generator and take some of the energy out of the car while slowing it down. If you

    give the electric motor more time to slow the vehicle, it can recover more of the energy.

    If you stop quickly, the brakes on the car will do most of the work of slowing the car

    down, and that energy will be wasted.

    CONCLUSION

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    Using the concept of Hybridization of cars results in better efficiency and also

    saves a lot of fuel in todays fuel deficit world. Though at present the concept has

    been put in to maximum utilization by Honda & Toyota, it is indeed an important

    research avenue for other car manufacturing units as well. A hybrid gives a solution to all

    the problems to some extent. If proper research and development is done in this

    field, hybrid vehicle promises a practical, efficient, low pollution vehicle for the

    coming era. One can surely conclude that this concept and the similar ones to follow

    with even better efficiency & conservation rate are very much on the anvil in todays

    energy deficit world.

    REFERENCE

    IEEE spectrum July 1995

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    IEEE spectrum March 2001

    IEEE spectrum May 2001

    IEEE power & energy magazine May 2004

    Automotive technology by JACK ERJAVEC

    Automotive electrical equipments byP.L.KOHLI

    WWW.HOWSTUFFWORKS.COM

    WWW.HYBRID ELECTRIC VEHICLE. COM

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