Hybrid electric vehicles combine a conventional internal combustion engine with an electric motor and batteries. This allows for improved fuel efficiency through technologies like regenerative braking. Full hybrids can run on electric power alone for short distances, while mild hybrids only provide assistance to reduce fuel use. Plug-in hybrids can be charged by plugging into an external power source for even greater electric range. Challenges include high battery costs and weight, but ongoing research aims to improve battery technology for wider hybrid adoption.

1. Hybrid Electric vehicle
GUIDED BY:
MR. DILLIP KUMAR SAHOO
PRESENTED BY:
PRRAKASH KUMAR SATAPATHY
REGD NO:L14115002037
ELECTRICAL ENGINEERING
SEMESTER: 6TH

2. 1. Introduction
A hybrid electric vehicle (HEV) is a type of hybrid vehicle
and electric vehicle which combines a
conventional internal combustion engine (ICE)
propulsion system with an electric propulsion system. The
presence of the electric power train is intended to achieve
either better fuel economy than a conventional vehicle or
better performance.
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.In 1997 , the first modern hybrid
electric car, the Toyota Prius, was sold in Japan.
Hybrids can play a significant role in solving major
problems faced by the world,
Climate change
Air pollution
Oil dependence .

5. HYBRID ENGINE

7. 4. Working Of A Hybrid Electric vehicle
A conventional vehicle has a mechanical drive train that includes the fuel tank, the
combustion engine, the gear box, and the transmission to the wheels.
A HEV has two drive trains - one mechanical and one electric. The electric drive train
includes a battery, an electric motor, and power electronics for control.

8. 3. Levels Of Hybrid Electric Vehicles
3.1 Full hybrid
They feature idle-stop function
Regenerative braking
Most are capable of using the electric motor alone to propel the vehicle
The electric motor also assists the engine
Battery voltages are about 200 to 300 volts
3.2Medium hybrid
They feature idle-stop function
Regenerative braking
Most are not capable of using the electric motor alone to propel the vehicle
The electric motor usually assists the engine
Battery voltages are about 144 to 158 volts
3.3 Mild Hybrid
They feature idle-stop function
Regenerative braking
Are not capable of using the electric motor to propel the vehicle
These systems are usually 42 volts or less

11. 6. 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, because the combustion engine
works as a backup when the batteries are depleted.

12. 7.Battery requirements
 The first generation HEVs were sluggish since the battery development had not
aimed for high specific power, i.e. they could not discharge energy quickly enough. This
has been partly rectified by the development of improved battery types: nickel/metal
hydride and lithium-ion batteries. Current HEV batteries provide the vehicle with
ample power for driving but development is still ongoing, focusing on cost reduction
and extending the lifetime.
 The power required for HEV function is supplied by large battery stacks, usually
between50-70 kg for passenger cars 25 and 250-600 kg for bus batteries. Most HEV
buses today are fitted with a lead acid battery, but the use of more advanced and
expensive but better and longer lifetime nickel metal hydride batteries is increasing for
buses as is already the case for passenger cars.

13. 8. BATTERY RECHARGING
The Ni-MH batteries are recharged through a process call regenerative braking
Regenerative braking takes energy from the forward momentum of the vehicle
and captures it while coasting or braking.
Occasionally batteries are recharged by the electric motor
It is expected that most PHEV and EV owners will recharge their vehicles
overnight at home.

14. 9.Advantages Of Hybrid electric Vehicles
Lower emissions and better mileage.
Hybrids perform at par with the normal gasoline-powered vehicles, if not better.
Hybrids are reliable and comfortable.
There are purchase incentives for Hybrid vehicle owners (varies by state).
Hybrids are much cleaner cars than normal vehicles.
The future for hybrids looks bright with rapid developments in hybrid technology
to improve engine efficiency.
Due to the Regenerative Braking technology, the batteries need not be charged by
an external source.
Special warranties are provided for the battery pack, the electric motor other
costly items.
Hybrids help reduce the dependency on fossil fuels which directly affects fuel
prices.

15. 10. Disadvantages Of Hybrid Electric Vehicles
 High Cost: Hybrids cost anywhere from $2,000 to $5,000 more their non-
Hybrid versions.
 More weight due to battery packs.
 Some states charge additional fees for registration.
 In the event of an unfortunate accident, there is a risk of exposure to high
voltage wires.
 Complicated Architecture.
 Spare parts maybe hard to find and may be costly.
 Hybrids have a lower acceleration .
 Some batteries fail deliver in cold weather.
 Not suitable for long distance journey.

16. 11.Technology challenges and opportunities
 Time of battery changing is long.
 Batteries are heavy.
 Batteries are expensive.
 Low performance in hot or cold temperatures also may damage the battery
 Very sensitive to overcharge/undercharge(Battery life reduces dramatically)
 Contain toxic heavy metals, disposal issue
Opportunity for researchers:
Advance research projects on batteries are supported by
governments and industries

17. A technology exists to build a future with a significant
lower dependence on oil. Hybrids can play an important
role in realizing the future, filling the gap between
immediate improvements through conventional
technology. Hybrids can help drive passengers vehicle
oil consumption and global warming.
12.Conclusion