Hybrid Electric Vehicles-Introduction( Unit-1)

Course: Hybrid Electric Vehicles
Dr.G.Nageswara Rao
Professor

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Dr.G.Nageswara Rao
https://www.youtube.com/@GNR900

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Fundamentals of vehicle, components of conventional vehicle and
propulsion load; Drive cycles and drive terrain; Concept of electric vehicle
and hybrid electric vehicle; History of hybrid vehicles, advantages and
applications of Electric and Hybrid Electric Vehicles, different Motors
suitable for of Electric and Hybrid Electric Vehicles.
Architectures of HEVs, series and parallel HEVs, complex HEVs .Plug-in
hybrid vehicle, constituents of PHEV, comparison of HEV and PHEV;
Fuel Cell vehicles and its constituents.
PHEVs and EREVs blended PHEVs, PHEV Architectures, equivalent
electric range of blended PHEVs; Fuel economy of PHEVs, power
management of PHEVs, end-of-life battery for electric power grid support,
vehicle to grid technology, PHEV battery charging.

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Rectifiers used in HEVs, voltage ripples; Buck converter used in HEVs,
non-isolated bidirectional DC-DC converter, voltage source inverter,
current source inverter, isolated bidirectional DC-DC converter, PWM
rectifier in HEVs, EV and PHEV battery chargers.
Energy Storage Parameters; Lead–Acid Batteries; Ultra capacitors;
Flywheels – Superconducting Magnetic Storage System; Pumped
Hydroelectric Energy Storage; Compressed Air Energy Storage – Storage
Heat; Energy Storage as an Economic Resource

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TEXT BOOKS:
 Ali Emadi, Advanced Electric Drive Vehicles, CRC Press, Ist Edition 2017.
 Iqbal Hussein, Electric and Hybrid Vehicles: Design Fundamentals, CRC Press,3rd
Edition 2021.
REFERENCE BOOKS:
 MehrdadEhsani, YimiGao, Sebastian E. Gay, Ali Emadi, Modern Electric, Hybrid
Electric and Fuel Cell Vehicles: Fundamentals, Theory and Design, CRC Press,3rd
Edition 2019.
 James Larminie, John Lowry, Electric Vehicle Technology Explained, Wiley,2nd
Edition 2017.
 H. Partab Modern Electric Traction – Dhanpat Rai& Co, 2017.
 Pistooa G., “Power Sources Models, Sustanability, Infrstructure and the market”,
Elsevier 2008
 Mi Chris, Masrur A., and Gao D.W., “ Hybrid Electric Vehicle: Principles and
Applications with Practical Perspectives” 2nd Edition,2017.
Dr.G.Nageswara Rao...“Hybrid Electric Vehicles Principles And
Applications” B R Publications.

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UNIT-1
INTRODUCTION
Fundamentals of vehicle, components of conventional vehicle and
propulsion load; Drive cycles and drive terrain; Concept of electric vehicle
and hybrid electric vehicle; History of hybrid vehicles, advantages and
applications of Electric and Hybrid Electric Vehicles, different Motors
suitable for of Electric and Hybrid Electric Vehicles.

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Force is basically a push or a pull that causes an object to undergo a
change in speed, a change in direction, or a change in shape. A force
has both magnitude (size) and direction.

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Weight is the force of gravity. It acts in a downward direction—
toward the center of the Earth.
Thrust is the force that propels a flying machine in the direction of
motion. Engines produce thrust.
Drag is the force that acts opposite to the direction of motion. Drag
is caused by friction and differences in air pressure.
Lift is the force that acts at a right angle to the direction of motion
through the air. Lift is created by differences in air pressure.

Dr.G.Nageswara Rao
ELECTRIC VEHICLES

BR Publications Text Book
*Hybrid Electric Vehicles Principles And Applications*
Dr. G. Nageswara Rao
Dr. Y.N. Vijaya Kumar, Mrs. R.K. Padma Shini, Dr. P. Selvan
ISBN- *978-81-19489-03-9*
Amazon Link:
https://www.amazon.in/dp/8119489039?ref=myi_title_dp
Flipkart Link :
https://www.flipkart.com/product/p/itme?pid=9788119489039
DOI Number : https://doi.org/10.5281/zenodo.8177205

ELECTRIC VEHICLES
 Transport is a fundamental requirement of modern life, but the
traditional combustion engine is quickly becoming outdated.
 Petrol or diesel vehicles are highly polluting and are being quickly
replaced by fully electric vehicles.
 Fully electric vehicles (EV) have zero tailpipe emissions and are much
better for the environment.
The electric vehicle revolution
is here, and you can be part of
it. Will your next vehicle be an
electric one?
1. Lower running costs
2. Low maintenance cost
3. Zero Tailpipe Emissions
4. Tax and financial benefits
5. Petrol and diesel use is destroying our planet
6. Electric Vehicles are easy to drive and quiet
7. Convenience of charging at home
8. No noise pollution

Electric vehicles are not just the wave of the future. They are saving
lives today
1. Electric vehicles now include cars, transit buses, trucks of all sizes, and even
big-rig tractor trailers that are at least partially powered by electricity.
2. Electric vehicles are saving the climate — and our lives.
3. Electric vehicles have a smaller carbon footprint than gasoline-powered
cars, no matter where your electricity comes from.
4. Through their entire lifetime, electric cars are better for the climate.
5. Electric vehicles can charge up at home, at work, while you’re at the store.
6. Through all our electric vehicle work, Earth justice aims to ensure that the
people who are most impacted by pollution have the option to use truly
clean and zero-emissions vehicles.

Electric Vehicle
vs
Petrol Vehicle
Parameter Electric Vehicle Petrol Vehicle
Fuel Electrical energy Petrol
Power Electric motor
Internal combustion
engine
Cost
Expensive (High
price)
Affordable than
EVs
Cost of fuel Low High
Cost of maintenance Low High
Fuel efficiency
Higher in the city
and lower on
highways
Higher on highways
and lower in city
roads
Carbon emissions Zero High

Advantages of electric vehicle
1. Electric vehicles are easy to drive due to simple
controls.
2. They are silent in operation due to the absence
of mechanical parts.
3. EVs deliver quick acceleration due to the high
torque available.
4. Low maintenance and the service intervals are
not as frequent as petrol vehicles.
5. Low running cost.
6. Electric vehicles produce zero emissions and
help to reduce carbon footprints.
7. You can charge electric vehicle at your home
provided you install a home charging system.
8. Electric vehicles are eligible for government-
provided subsidies and tax benefits if you buy an
EV on loan.
Disadvantages of electric vehicle
1. The driving range of electric vehicles is
low, and you cannot cover long distances
without charging the vehicle.
2. Lack of public charging stations can be
an issue when driving your EV for long
distances.
3. Installing a home charging module is an
added expense.
4. Lack of expert mechanics to
service/repair eco-friendly vehicles.
5. Replacing the battery pack of an EV is
costly.

A vehicle that works on an electric motor instead of an
internal combustion engine is called an Electric Vehicle
Electric Vehicles are useful as they reduce the harmful
emission released by the engine-based vehicle. They can
be very helpful in reducing air pollution in the
atmosphere.

WORKING OF ELECTRIC VEHICLE
 Electricity is transferred from a
battery to a controller.
 The controller then sends the
electricity to the electric motors
when needed.
 The accelerator is connected to a
variable switch which tells the
controller how much power to
send to the electric motors.
 Power output can vary from zero
to full as needed.

Electric Vehicle (EV)
• An EV is defined as a vehicle that can be powered by an electric motor that
draws electricity from a battery and is capable of being charged from an external
source.
• An electric vehicle, also called an electric drive vehicle, uses one or more
electric motors or traction motors for propulsion. An electric vehicle may be
powered through a collector system by electricity from off-vehicle sources, or
may be self-contained with a battery, solar panels or a generator to convert fuel
to electricity. EVs include road and rail vehicles, surface and underwater
vessels, electric aircraft and electric spacecraft.

Key Parts Of A
Battery Electric Vehicle

Key Parts Of A Battery Electric Vehicle
Charging port or vehicle inlet: It is a connector present on the electric vehicle to allow it to
be connected to an external source of electricity for charging.
Power electronic converter: A power electronic converter is made of high power fast-acting
semiconductor devices, which act as high-speed switches. Different switching states alter the
input voltage and current through the use of capacitive and inductive elements. The result is an
output voltage and current, which is at a different level to the input.
On-board charger: It is an AC-to-DC power electronic converter (often referred to as a
rectifier) that takes the incoming AC electricity supplied via the charge port and converts it to
DC power for charging the traction battery. Using the battery management system, it regulates
the battery characteristics such as voltage, current, temperature, and state of charge.
Traction battery pack: It is a high voltage battery used to store energy in the electric car and
provide power for use by the electric traction motor.
Battery power converter: It is a DC-to-DC power electronic converter that converts the
voltage of the traction battery pack to the higher-voltage of the DC-bus used for power
exchange with the traction motor.

Motor drive: It is a DC-to-AC (often referred to as inverter or the variable frequency drive)
or at times a DC-to-DC power electronic converter, used to convert power from the high
voltage DC bus to AC (or at times DC) power for the operation of motor. The converter is
bidirectional for operating in both driving and regenerative braking mode.
Traction electric motor/generator: It is the main propulsion device in an electric car that
converts electrical energy from the traction battery to mechanical energy for rotating the
wheels. It also generates electricity by extracting energy from the rotating wheels while
braking, and transferring that energy back to the traction battery pack.
Transmission: For an electric car, usually a single gear transmission with differential is used
to transfer mechanical power from the traction motor to drive the wheels.
Power electronics controller: This unit controls the flow of electrical power in the different
power electronic converters in the electric car.
Battery (auxiliary): In an electric drive vehicle, the auxiliary battery provides electricity to
start the car before the traction battery is engaged and is also used to power the vehicle
accessories.

EV parameters:
Important parameters for understanding electric vehicles.
1.Battery Capacity
2.State Of Charge
3.Range
4.Energy Consumption Per Kilometer
5.Motor Power

1.Nominal battery capacity (Enom, in Wh or kWh): It is total electric energy that can be
stored in the battery. Alternately, it is the maximum amount of electric energy that can be
extracted from a fully charged battery state to the empty state.Generally speaking, EV batteries
have a battery capacity between 5 kWh to 100 kWh depending on the type of EV. The higher
the battery capacity, the more energy it can store and the longer the time it takes to fully charge
it. The battery capacity is often referred to as the energy content or energy capacity of the
battery.
2.State of charge, SOC (BSOC, in %): The battery state of charge (SoC) is defined as the
ratio between the amount of energy currently stored in the battery, Ebatt and the total battery
capacity, Enom BSOC=(Ebatt / Enom) 100.
3.Range (Rmax, in km): It is the maximum distance that can be driven by an electric car
when the battery is full. Usually an electric car is tested using a standardized driving cycle to
estimate the range, e.g. New European Driving Cycle (NEDC), Worldwide harmonized Light
vehicles Test Procedure (WLTP) or the EPA Federal Test Procedure. The range can be
expressed in miles, kilometer or other units based on the region. In this set of definitions, we
stick to the European convention of using kilometer.

Available Range (R, in km): It is the maximum distance that can be driven by an electric car
based on the current state of charge of the battery.
4.Energy consumption per kilometer (D, in kWh/km): When an electric car is tested using
a standardised driving cycle, the EV efficiency is the energy consumed from the batteries per
unit distance drive. In some cases, the energy drawn from the grid to charge the battery is
considered as well. It can be expressed in kilowatt-hour per kilometer (or) kilowatt-hour per
mile.
MPGe or miles per gallon equivalent: MPGe is the distance in miles traveled per unit of
electric energy consumed by the vehicle. The ratings are based on United States
Environmental Protection Agency (EPA) formula, in which 33.7 kilowatt-hours (121
megajoules) of electricity is equivalent to one gallon of gasoline.
5.Motor power (Pm, in W): It is the power delivered by the motor to the wheels for
propulsion. The motor power is positive or negative based on whether the car is driving or
under regenerative braking. The motor power can be expressed as a product of the motor
torque, Tm and the motor rotational speed, wm and the units normally used are watts (W),
kilowatts (kW) or horsepower(hp). The rotational speed is normally expressed in radians per
second (rad/s) or rotations per minute (rpm). The torque is normally expressed in newton-
meter (Nm).

BATTERY ELECTRIC VEHICLES (BEV)

Plug in Hybrid electric vehicle (PHEV)

Schematic diagram of the hybrid power system structure

Hybrid electric Vehicle key components
•The auxiliary battery: It provides electricity to start the car before engaging the traction battery;
•The DC/DC converter: It converts the higher-voltage DC power from the traction battery to the lower-voltage
DC power to run the vehicle accessories and recharge the auxiliary battery;
•The electric generator: This component provides electricity from rotating the wheels while braking, transferring
the energy to the traction battery.
•The electric traction motor: This motor uses power from the traction battery to drive the wheels.
•The exhaust system: It is designed with a three-way catalyst to reduce emissions from the engine out through the
tailpipe.
•The spark-ignited internal combustion engine: It allows air to combine with fuel and ignite by the spark from
a spark plug.
•The power electronics controller: This part manages the flow of electric energy from the traction battery,
allowing the control of the speed of the traction motor and the torque being produced.
Regenerate Braking
Unlike an electric vehicle (EV), a hybrid electric vehicle cannot be plugged in for the battery to charge. Instead, the battery is
charged with the help of regenerative braking and by the internal combustion engine. The electric motor powers the vehicle
as well as resists its motion. When you apply the brakes to slow down, this resistance slows down the wheel and
simultaneously recharges the batteries.
Dual Power
Power can come from the engine, motor, or both, depending on driving circumstances and whether the car is a full hybrid or
mild hybrid.

1. Battery Electric Vehicles (BEVs): vehicles 100% are propelled by electric power. BEVs
do not have an internal combustion engine and they do not use any kind of liquid fuel.
BEVs normally use large packs of batteries in order to give the vehicle an acceptable
autonomy. A typical BEV will reach from 160 to 250 km, although some of them can
travel as far as 500 km with just one charge. An example of this type of vehicle is the
Nissan Leaf , which is 100% electric and it currently provides a 62 kWh battery that
allows users to have an autonomy of 360 km.
2. Plug-In Hybrid Electric Vehicles (PHEVs): hybrid vehicles are propelled by a
conventional combustible engine and an electric engine charged by a pluggable external
electric source. PHEVs can store enough electricity from the grid to significantly
reduce their fuel consumption in regular driving conditions. The Mitsubishi Outlander
PHEV provides a 12 kWh battery, which allows it to drive around 50 km just with the
electric engine. However, it is also noteworthy that PHEVs fuel consumption is higher
than indicated by car manufacturers.
3. Hybrid Electric Vehicles (HEVs): hybrid vehicles are propelled by a combination of a
conventional internal combustion engine and an electric engine. The difference with
regard to PHEVs is that HEVs cannot be plugged to the grid. In fact, the battery that
provides energy to the electric engine is charged to the power generated by the vehicle’s

4. Fuel Cell Electric Vehicles (FCEVs): these vehicles are provided with an electric engine
that uses a mix of compressed hydrogen and oxygen obtained from the air, having water as the
only waste resulting from this process. Although these kinds of vehicles are considered to
present “zero emissions”, it is worth highlighting that, although there is green hydrogen, most
of the used hydrogen is extracted from natural gas. The Hyundai Nexo FCEV is an example of
this type of vehicles, being able to travel 650 km without refueling.
5. Extended-range EVs (ER-EVs): these vehicles are very similar to those ones in the BEV
category. However, the ER-EVs are also provided with a supplementary combustion engine,
which charges the batteries of the vehicle if needed. This type of engine, unlike those provided
by PHEVs and HEVs, is only used for charging, so that it is not connected to the wheels of the
vehicle. An example of this type of vehicles is the BMW i3, which has a 42.2 kWh battery that
results in a 260 km autonomy in electric mode, and users can benefit an additional 130 km
from the extended-range mode.

CONCEPT OF
HYBRID ELECTRIC VEHICLE
What is a Hybrid Electric Vehicle (HEV)
A Hybrid Electric Vehicle is a type of vehicle that uses a combination of an
Internal Combustion (IC) engine and an electric propulsion system. The
electric powertrain may enhance fuel efficiency, increase performance, or
independently propel the vehicle on pure electric power, depending on the
type of hybrid system.
Hybrid Electric Vehicle (HEV) is a vehicle which is using two energy
sources for propulsion, at least one of the energy sources being electrical
energy. The vast majority of hybrid electric vehicles are using a combination
of petrol (gasoline) engines and electric motor(s).

Hybrid vehicle technology
Hybrid vehicle technology is a combination of an internal
combustion engine and an electric battery operated motor.
Advantages of hybrid vehicle technology:
1. Fuel consumption is less due to electric batteries.
2. Less emission of carbon dioxide makes it eco-friendly.
3. Gives better mileage than a conventional engine
vehicle, thus is cost effective.
4. Less dependence on fossil fuels.

Hybrid-Electric Vehicles (HEVs) combine the advantages of both the internal combustion engine (or
gasoline engines if you like) and electric motors that use energy stored in batteries. The key areas
of performance are regenerative braking, dual power sources, and less idling. Hybrid electric cars
work by charging the battery through regenerative braking and by the internal combustion engine,
and not only by directly plugging in the vehicle to charge the batteries. Through the electric motor
and the battery, extra power is provided, which allows the use of a smaller engine and even
provides auxiliary loads, which could reduce the engine’s idling. These features result in better fuel
economy while maintaining great vehicle performance.
Hybrid electric Vehicle key components.
The auxiliary battery: It provides electricity to start the car before engaging the traction battery;
The DC/DC converter: It converts the higher-voltage DC power from the traction battery to the lower-voltage DC power
to run the vehicle accessories and recharge the auxiliary battery;
The electric generator: This component provides electricity from rotating the wheels while braking, transferring the
energy to the traction battery.
The electric traction motor: This motor uses power from the traction battery to drive the wheels.
The exhaust system: It is designed with a three-way catalyst to reduce emissions from the engine out through the
tailpipe.
The spark-ignited internal combustion engine: It allows air to combine with fuel and ignite by the spark from a spark
plug.
The power electronics controller: This part manages the flow of electric energy from the traction battery, allowing the
control of the speed of the traction motor and the torque being produced.

Working Principle of HEV
Fuel Tank
Battery
Primary Energy Converter - Internal Combustion Engine
Secondary Energy Converter - Electric Machine (Motor/Generator)

Hybrid vehicle is using 2 energy sources, with 2 energy converters.
There is primary energy source (1) and a secondary energy source (2)
There is primary energy converter (1) and a secondary energy converter (2)
 for a HEV, the primary energy source is the fuel tank and the secondary energy source is
the battery
 the primary energy source has much more energy content than the secondary energy
source
 energy can be transferred from the primary energy source towards the secondary energy
source but not vice versa
 the transfer of energy from the primary source towards the secondary source is done
through energy converters
 for a HEV, the primary energy converter is the internal combustion engine and the
secondary energy converter is the electric machine (motor/generator)
 part of the kinetic energy of the vehicle can be recovered during braking only by the
secondary energy converter and stored in the secondary energy source
 both energy converters can apply traction torque to the wheel in the same time

How does an HEV work?
 Powering a hybrid electric vehicle is an IC engine and an electric motor.
 The electric motor utilises the electrical energy stored in the battery pack.
 The battery pack gets charged via regenerative braking or through a generator
that is run by the internal combustion engine.
 An HEV does not need to be plugged into a power source to charge the
battery.
 The electric motor and IC engine work in conjunction to propel the vehicle.
 The additional power from the electric motor assists the engine, and it
enhances the performance and improves the fuel economy.
 The battery pack can also power other electrical components such as lights.
 The electric powertrain also saves fuel via the engine start/stop technology,
wherein the engine automatically shuts off when idle and starts automatically
when the driver presses the throttle pedal.

Types of Hybrid Electric Vehicles
There are three types of HEVs based on power delivery and distribution.
1. Series hybrid
In a series hybrid system, the IC engine powers the electric generator, which drives the electric
motor and charges the battery. In this setup, the engine does not directly power the wheels.
Series hybrid is also called a range extender since the engine powers the electric motor and the
battery pack.
2. Parallel hybrid
In this system, both the engine and electric motor work parallel to propel the vehicle. The
engine and the electric motor deliver optimum power for the efficient functioning of the car.
The battery pack gets charged via regenerative braking. Regenerative braking is a process of
utilising the kinetic energy produced while slowing the vehicle down to charge the battery
pack.
3. Series-parallel hybrid
A series-parallel is a flexible system wherein the IC engine, and electric motor can work in
conjunction or independently. The power delivery or the power distribution helps the vehicle
achieve maximum efficiency in terms of power output or fuel-efficiency.

Difference between Electric Vehicles and Hybrid Electric Vehicles
Parameters Electric Vehicles Hybrid Electric Vehicles
Primary power source Electricity Gasoline fuel
Working mechanism
Electric motor powers
the wheels.
The IC engine and electric motor work in
tandem to propel the vehicle.
Battery charging
You need to plug into a
power source to charge
the battery pack.
You don't need to plug into an external power
source as the battery gets charged via
generator/regenerative braking.
Emission levels
EVs produce zero
emission.
HEVs are Low Emission Vehicles (LEVs) since
they produce fewer emissions than
conventional vehicles.
Running cost Low High
Upfront cost (Price) High Lower than electric vehicles.
Driving range Low High
Vehicle life
You can use an EV until
the battery pack lasts.
You can drive an HEV for a longer period since
an IC engine lasts longer than a battery pack.

Advantages of Electric Vehicles
1. Low Noise Pollution
2. Secure Environment
3. Low Maintenance Cost
4. More Convenient
5. No Fuel
6. Natural Resource Saving
7. Increasing Popularity
8. Parking For a Low Fee
9. Golden Investment Opportunities
10. Subsidy Benefits
Disadvantages of Electric Vehicles
1. Higher Purchase Cost
2. Low Speed and Range
3. Low Price on Selling
4. The Inconvenience of Service
Station
5. Low Energy
6. Battery Expenses
7. Slow Charging
8. Expensive Recharging Options
9. Problem For Fuel-Producing
Countries
10. Fewer Users

1.Consumer Electronics.
2.Public Transportation.
3.Aviation.
4.Electricity Grid.
5.Renewable Energy Storage.
6.Military.
7.Spaceflight.
8.Wearable Technology.
APPICATIONS OF ELECTRIC VEHICLES

Advantages of a Hybrid Vehicles
1. Environmentally Friendly: One of the biggest advantages of a hybrid car over a gasoline-powered car is that
it runs cleaner and has better gas mileage, which makes it environmentally friendly.
A hybrid vehicle runs on a twin-powered engine (gasoline engine and electric motor) that cuts fuel
consumption and conserves energy. Sure, it still uses gasoline, but the amount it needs to operate is
significantly reduced.
2. Financial Benefits:Hybrid cars are supported by many credits and incentives that help make them affordable.
Lower annual tax bills and exemption from congestion charges make running these cars generally cheaper than
their pure gasoline-powered counterparts.
3. Less Dependence on Fossil Fuels:A Hybrid car is much cleaner and requires less fuel to run, which means
fewer emissions and less dependence on fossil fuels. This, in turn, also helps to reduce the price of gasoline in
the domestic market.
4. Regenerative Braking System:Each time you apply the brake while driving a hybrid vehicle, it helps you
recharge your battery a little. An internal mechanism kicks in that captures the energy released and uses it to charge the
battery, which in turn eliminates the amount of time and need for stopping to recharge the battery periodically.
5. Built From Light Materials:Hybrid vehicles are made of lighter materials, meaning less energy is required to run them.
The engine is also smaller and lighter, which also saves a lot of energy.
6. Assistance From Electric Motor:The electric motor assists the internal combustion engine in case of accelerating, passing
or climbing a hill.
7. Smaller Engines:The gasoline engines in hybrid cars are usually small, light, and highly efficient as they don’t have to
power the car alone.

8. Automatic Start and Stop: In hybrid cars, the engine is automatically shut off when the vehicle is idle and
starts when the accelerator is pressed.
Compared to traditional hybrid vehicles, PHEVs can drive longer distances at higher speeds. Hydrogen
fuel cell vehicles have lower energy emissions because they emit only water vapor and warm air.
9. Electric-Only Drive: Hybrid vehicles can be driven entirely on electricity. This usually happens while moving
at low speeds, when the engine is idling at a stoplight, or when the engine starts up.
Normally, the internal combustion engine starts operating only at higher speeds, where it has more efficiency.
This helps increase the overall fuel efficiency of the vehicle.
10. Higher Resale Value: With a continuous increase in the price of gasoline, more and more people are turning towards
hybrid cars. The result is that these green vehicles have started commanding higher-than-average resale values. So, if you
are unsatisfied with your vehicle, you can always sell it at a premium price to buyers looking for it.
There are many advantages to owning a hybrid car. The one thing you will like the best is how it helps control your budget
as gas prices increase.
The other benefit that is not seen directly is how owning and driving a hybrid car impacts the environment. That’s
because it reduces your dependence on fossil fuels and lowers your carbon imprint on the environment.

Disadvantages of a Hybrid Electric Vehicles:
There are disadvantages to owning a hybrid car, but they are probably not what you think.
Contrary to the popular myth, hybrid cars have just as much power as regular cars and have no issues with
mountain driving or towing. The disadvantages will depend on the type of hybrid fuel that your vehicle uses.
1. Less Power;Hybrid cars have twin-powered engines. The gasoline engine, which is the primary power source,
is much smaller than what you get in single-engine powered cars, while the electric motor isn’t as powerful
either.
The combined power is often less than that of a gas-powered engine. In fact, the power generated by this car is
more suited for city driving and not for long-distance travel or applications where speed and acceleration are
imperative.
2. Can Be Expensive: Hybrid cars are comparatively more expensive than regular petrol cars. However, that
extra amount can be offset with lower running costs and tax exemptions.
3. Poorer Handling: Incorporating both a gasoline-powered engine and a lighter electric engine, hybrid cars
require powerful battery packs, which increase weight and consume additional space within the vehicle.
Unfortunately, the extra weight contributes to fuel inefficiency, prompting manufacturers to prioritize weight
reduction. Consequently, they have downsized motors and batteries while providing less support in the
suspension and body to counterbalance the added mass.
4. Higher Maintenance Costs:The presence of a dual engine and continuous technological improvements make it
difficult for mechanics to repair the car, and the maintenance cost is also much higher. It is also difficult to find a
mechanic with such expertise.

5. Accidents from High Voltage in Batteries
In an accident, the high voltage inside the batteries can prove lethal for you. There is a high chance of you
getting electrocuted in such cases, which can also make the task difficult for rescuers to get other passengers
and the driver out of the car.
6. Battery Replacement is Pricey
According to Green Car Reports, battery replacement in hybrid vehicles is currently rare. However, if a battery
needs to be replaced, it can get pricey.
7. Battery Recycling Is Very Expensive
Once batteries pass their useful life cycle, they can be recycled to harvest usable materials for repurposing.
This removes waste from the environment, which by the way, is a good thing.
However, the main issue with recycling lies in the recycling costs. Although lithium is 100% recyclable, extracting it costs
too much, and sometimes economic gain may not adequately justify the effort put into the recycling process.
In fact, in most cases, lithium recycling is only done because of federal mandates and/or ecological purposes.
8. Hydrogen Fuel Cell Issues
The source of hydrogen can be both “clean” sources, such as solar or wind power, or “dirty” sources like coal and natural
gas. Sourcing from coal and natural gas undermines the ecological motive for using hydrogen fuel cell vehicles.
Production of hydrogen is also expensive, and the fuel cells require refueling at a hydrogen station. At present, these
stations are only located in California and near Toronto.

Assess Your Priorities – Pick your top priorities, including price, range, top speed, and
acceleration. This will enable you to concentrate on the motors that best suit your demands
while also reducing the number of possible choices.
Compare Motor Types – Compare the various motor types covered earlier in this post,
assessing the advantages and disadvantages of each. Remember that AC motors offer
superior performance and efficiency even when DC motors could be cheaper.
Consult Experts and Online Resources – Consult specialists, either in person or online,
and use online tools like forums and blogs to gain insight from other people’s experiences.
You can obtain important insights and decide more wisely as a result of this.

Types of Motors used in Electric Vehicles
Electric Motors used in Electric Vehicles
1. DC Series Motor
2. Brushless DC Motor
3. Permanent Magnet Synchronous Motor (PMSM)
4. Three Phase AC Induction Motors
5. Switched Reluctance Motors (SRM)

1. DC Series Motor
High starting torque capability of the DC Series motor makes it a suitable option for
traction application. The advantages of this motor are easy speed control and it can also
withstand a sudden increase in load. All these characteristics make it an ideal traction
motor. The main drawback of DC series motor is high maintenance due to brushes and
commutators.
2. Brushless DC Motors
It is similar to DC motors with Permanent Magnets. It is called brushless because it does
not have the commutator and brush arrangement. The commutation is done electronically
in this motor because of this BLDC motors are maintenance free. BLDC motors have
traction characteristics like high starting torque, high efficiency around 95-98%, etc.
BLDC motors are suitable for high power density design approach. The BLDC motors are
the most preferred motors for the electric vehicle application due to its traction
characteristics.

BLDC motors further have two types
i. Out-runner type BLDC Motor:
In this type, the rotor of the motor is present outside and the stator is present inside. It is also
called as Hub motors because the wheel is directly connected to the exterior rotor. This type of
motors does not require external gear system. In a few cases, the motor itself has inbuilt
planetary gears. This motor makes the overall vehicle less bulky as it does not require any gear
system. It also eliminates the space required for mounting the motor. There is a restriction on
the motor dimensions which limits the power output in the in-runner configuration. This motor
is widely preferred by electric cycle manufacturers like Hullikal, Tronx, Spero, light speed
bicycles, etc. It is also used by two-wheeler manufacturers like 22 Motors, NDS Eco Motors,
etc.
ii. In-runner type BLDC Motor:
In this type, the rotor of the motor is present inside and the stator is outside like conventional
motors. These motor require an external transmission system to transfer the power to the
wheels, because of this the out-runner configuration is little bulky when compared to the in-
runner configuration. Many three- wheeler manufacturers like Goenka Electric Motors, Speego
Vehicles, Kinetic Green, Volta Automotive use BLDC motors. Low and medium performance
scooter manufacturers also use BLDC motors for propulsion.

It is due to these reasons it is widely preferred motor for electric vehicle application. The main drawback is the high cost
due to permanent magnets. Overloading the motor beyond a certain limit reduces the life of permanent magnets due to
thermal conditions.
3. Permanent Magnet Synchronous Motor (PMSM)
This motor is also similar to BLDC motor which has permanent magnets on the rotor. Similar to BLDC motors these motors
also have traction characteristics like high power density and high efficiency. The difference is that PMSM has sinusoidal
back EMF whereas BLDC has trapezoidal back EMF. Permanent Magnet Synchronous motors are available for higher power
ratings. PMSM is the best choice for high performance applications like cars, buses. Despite the high cost, PMSM is
providing stiff competition to induction motors due to increased efficiency than the latter. PMSM is also costlier than BLDC
motors. Most of the automotive manufacturers use PMSM motors for their hybrid and electric vehicles. For example,
Toyota Prius, Chevrolet Bolt EV, Ford Focus Electric, zero motorcycles S/SR, Nissan Leaf, Hinda Accord, BMW i3, etc use
PMSM motor for propulsion.
4. Three Phase AC Induction Motors
The induction motors do not have a high starting toque like DC series motors under fixed voltage and fixed frequency
operation. But this characteristic can be altered by using various control techniques like FOC or v/f methods. By using these
control methods, the maximum torque is made available at the starting of the motor which is suitable for traction
application. Squirrel cage induction motors have a long life due to less maintenance. Induction motors can be designed up
to an efficiency of 92-95%. The drawback of an induction motor is that it requires complex inverter circuit and control of
the motor is difficult.

In permanent magnet motors, the magnets contribute to the flux
density B. Therefore, adjusting the value of B in induction motors
is easy when compared to permanent magnet motors. It is because
in Induction motors the value of B can be adjusted by varying the
voltage and frequency (V/f) based on torque requirements. This
helps in reducing the losses which in turn improves the efficiency.
Tesla Model S is the best example to prove the high performance
capability of induction motors compared to its counterparts. By
opting for induction motors, Tesla might have wanted to eliminate
the dependency on permanent magnets. Even Mahindra Reva e2o
uses a three phase induction motor for its propulsion. Major
automotive manufacturers like TATA motors have planned to use
Induction motors in their cars and buses. The two-wheeler
manufacturer TVS motors will be launching an electric scooter
which uses induction motor for its propulsion. Induction motors
are the preferred choice for performance oriented electric vehicles
due to its cheap cost. The other advantage is that it can withstand
rugged environmental conditions. Due to these advantages, the
Indian railways has started replacing its DC motors with AC
induction motors.

5. Switched Reluctance Motors (SRM)
Switched Reluctance Motors is a category of variable reluctance motor with double saliency. Switched
Reluctance motors are simple in construction and robust. The rotor of the SRM is a piece of laminated steel
with no windings or permanent magnets on it. This makes the inertia of the rotor less which helps in high
acceleration. The robust nature of SRM makes it suitable for the high speed application. SRM also offers high
power density which are some required characteristics of Electric Vehicles. Since the heat generated is mostly
confined to the stator, it is easier to cool the motor. The biggest drawback of the SRM is the complexity in
control and increase in the switching circuit. It also has some noise issues. Once SRM enters the commercial
market, it can replace the PMSM and Induction motors in the future.
Insights for Selecting the Right Motor for your EV
For selecting the appropriate electric vehicle motors, one has to first list down the requirements of the
performance that the vehicle has to meet, the operating conditions and the cost associated with it. For example,
go-kart vehicle and two-wheeler applications which requires less performance (mostly less than 3 kW) at a low
cost, it is good to go with BLDC Hub motors. For three-wheelers and two-wheelers, it is also good to choose
BLDC motors with or without an external gear system. For high power applications like performance two-
wheelers, cars, buses, trucks the ideal motor choice would be PMSM or Induction motors. Once the synchronous
reluctance motor and switched reluctance motor are made cost effective as PMSM or Induction motors, then one
can have more options of motor types for electric vehicle application.

maglev, also called magnetic levitation train or maglev train, a
floating vehicle for land transportation that is supported by either
electromagnetic attraction or repulsion. Maglevs were
conceptualized during the early 1900s by American professor and
inventor Robert Goddard and French-born American engineer Emile
Bachelet and have been in commercial use since 1984, with several
operating at present and extensive networks proposed for the future

 Maglev (magnetic levitation), is a system of train transportation that uses
two sets of electromagnets:
 one set to repel and push the train up off the track, and another set to
move the elevated train ahead, taking advantage of the lack of friction.
 Such trains rise approximately 10 centimetres (4 in) off the track.
 There are both high-speed, intercity maglev systems (over 400 kilometres
per hour or 250 miles per hour), and low-speed, urban maglev systems
(80–200 kilometres per hour or 50–124 miles per hour) under
development and being built.
 The Shanghai maglev train is the only maglev train in commercial
operation that can be considered as high speed.

MAGLEV is an acronym of magnetic levitation. The most spectacular applications of this would be
maglev trains. The coaches of the train do not slide over steel rails but float on a four inch air cushion above the
track using Meissner effect of super conducting magnets.
 The train has a superconducting magnet built into the base of the carriages.
 An aluminium guide way is laid on the ground and carriers electric current.
 The walls of the guide way have a series of horizontal and vertical coils mounted inside the guide
way. These coils are made up of normal conductors
 The current flowing through its horizontal coils produce a vertical magnetic field. By Meissner
effect the superconducting magnet S expels the vertical magnetic flux. This levitates the train and
keeps it afloat the guide way, the horizontal coils are thus called levitating coils.
 On the other hand current passing through the vertical coil produce a horizontal magnetic field
which pushes the train forward. Thus the vertical coils are called propelling coils.
 The train is fitted with retractable wheels similar to the wheels of an aircraft. Once the train is
levitated in air the wheels are retracted into the body and the train glides forward on the air
cushion.
 When the train is to be halted the current through the levitating and propelling coils are switched
off. The train descends slowly on to the guide way and runs some distance on it till it stops.
 The utility of such levitation is that in the friction the energy loss is minimized allowing the speed
of the train rise up to 581 kmph.

Explain the principle behind maglev trains
 Maglev is short for Magnetic Levitation, in which trains float on a
guideway using the principle of magnetic repulsion.
 When two magnets are brought near each other, either their north
poles or south poles face each other; they repel each other.
 When the north pole of a magnet is brought near the south pole of
another magnet, they attract each other.
 Thus, like poles repel and, unlike poles, attract each other.
Hence, the magnetic repulsion principle is used in maglev trains.

Advantages of Hybrid Vehicles
1. Fuel Economy
2. Require Less Maintenance
3. Light Materials
4. A More Reliable Fuel Type
5. Good Resale Value
Disadvantages of Hybrid Vehicles
1. Higher Insurance
2. Higher Upfront Cost
3. Performance
4. Poorer Handling
5. Battery Replacement Can Be Expensive

Hybrid Electric Vehicles-Introduction( Unit-1)

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