Hybrid Electric Vehicle
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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; it's 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. 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 world started down a new road in 1997 when the first modern hybrid electric car, the Toyota Prius, was sold in Japan. Two years later, the United States saw its first sale of a hybrid, the Honda Insight. These two Vehicles, followed by the Honda Civic Hybrid, marked a radial change in the type of car being offered to the public: vehicles that bring some of the benefits of battery electric vehicles into the conventional gasoline powered cars and trucks we have been using for more than 100 years. In the coming years, hybrids can play a significant role in addressing several of the major problems faced by the United States and the whole world today: climate change, air pollution and oil dependence. Whether this new technology delivers on its promise hinges on the choices automakers, consumers and policymakers make over the coming years. Poor choices could result in hybrids that fall short even of what conventional technology could deliver on fuel economy, emission or both. If they designed well, these hybrids can equal or better the utility, comfort, performance and safety we’ve come to expect, while saving us thousand of dollars at the gas pump.
A hybrid electric (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
What is HEV?
The combination of an internal combustion engine(ICE) with one or more electric motor or generators and a battery pack
Combines propulsion system with RESS and gets better fuel economy
An HEV uses less gasoline because the electric motor does some of the work
How HEV works
Hybrid-electric vehicles (HEVs) combines the benefits of gasoline engines and electric motors and can be configured to obtain different objectives, such as improved fuel economy, increased power or additional auxiliary power for electronic devices and power tools. Some of the advanced technologies typically used by hybrid include.
REGENERATIVE BREAKING: The electric motor applies resistance to the drive train causing the wheels to slow down. IN return, the energy from the wheels turns the motor, which functions as a generator, converting energy normally wasted during coasting and breaking into electricity, which is stored in a battery until needed by the electric motor
ELECTRIC MOTOR DRIVE/ASSIST: The electric motor provides additional power to assist the engine in accelerating, passing or hill climbing. This allows a smaller, more efficient engine to be used. IN some vehicles, the motor alone provides power for low-speed driving condition where internal combustion engines are least efficient.
AUTOMATIC START/SHUTOFF: Automatically shuts off the engine when the vehicle comes to a stop and restarts it when the accelerator is pressed. This prevents wasted energy from idling.
Process of Working
Full hybrids 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 electric motor as the sole source of propulsion for low-speed, low-acceleration driving, such as in stop-and-go traffic or for breaking up.
This electric-only driving mode can further increase fuel efficiency under some driving conditions.
When a full hybrid vehicle is initially started, the battery typically powers all accessories
The gasoline engine only starts if the battery needs to be charged or the accessories require more power than available from the battery
The battery stores energy generated from the gasoline engine or during regenerative braking from the electric motor. Since the battery powers the vehicle at low speeds, it is larger and holds much more energy than battery used to start conventional vehicles
For initial acceleration and low-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 the engine into electricity. This is stored in the battery.
At speeds above mid-range, both the engine and electric motor are used to propel the vehicle
The gasoline engine provides power to the drive-train directly and to the electric motor via the generator
During heavy accelerating or when additional power is needed the gasoline engine and electric motor are both use to propel the vehicle
Regenerative braking converts otherwise wasted energy from baking into electricity and stores it in battery
In regenerative braking, the electric motor is reversed so that, instead of using electricity to run the wheels, the rotating wheels turn the motor and create electricity. Using energy from the wheels turn the motor slows the vehicle down
When the vehicle is stopped, such as at a red light, the gasoline engine and electric motor shut off automatically so that energy is not wasted I idling
All other systems, including the electric air conditioning, continue to run
Rollover area: Battery: The battery stores energy generated from the gasoline engine or, during regenerative braking, from the electric motor. Since the battery powers the vehicle at low speeds, it is larger and holds much energy than batteries used to start conventional vehicles.
The cost of maintenance is reduced due to operation of hybrid technology
Regenerative braking reduces wear on brakes
Idle stop extends battery life
Electric accessories reduce load on engine.
Battery charge is computer controlled which extends battery life
USE OF HEV
When it comes to purchasing a car many of us used to only think about how it looked and how fast we could go in it. But that was before gas prices skyrocketed and we were forced to think more about convenience rather then what we really wanted. People who are trying to purchase new cars are not in search of a car that receives good gas mileage.
Many manufacturers are designing their cars around this one feature to make them more appealing for people. One of the most common car that people feel can save them the most money are hybrids. These cars combine the use of two different types of engines in order to produce low measures of pollution.
Thanks to the uniqueness of the engine it is one of the quietest types of cars that you will ever see. They are designed with a fuel tank that is connected to the gasoline engine - but it is smaller and more efficient then in the average vehicle. It is also designed with an electric motor that uses batteries to function.
These hybrids have many features that include being able to travel long distances without using large amounts of fuel. When the car is idling or when it is traveling at low speeds it will switch to battery power. These batteries can be recharged at home.
When stopping the car it uses the electric motor and what is commonly known as regenerative braking. In the standard car they used friction to stop the car - but in a hybrid car kinetic energy will charge up the battery and use the energy to stop it. One of the best features that it has is the ability to shut itself off. When the car is idling it will automatically shut off and save fuel.
The Cash For Clunkers program is used to help people save money and purchase a car they can afford. Some of the most popular types are the Hybrids - which help to save people in gas money
ADVANTAGES OF HEV
Cost of recharge
Stabilization of the grid
Use less fuel
Value Added Features
DISADVANTAGES OF HEV
Heating of electric vehicles
Reduced but not emission free
More expensive e than conventional vehicles
Has a payback period in average use
A Cooler, Cleaner and Secure Future
A technology exists to build a future with a significant lower dependence on oil and a cleaner, cooler atmosphere. With sufficient political will and automaker participation, this future can arrive in time to address these significant and growing problems. Hybrids can play an important role in realizing this future, filling the gap between immediate improvements through conventional technology; hybrids can help drive passengers vehicle oil consumption and global warming emulsions from cars and trucks below 1990 levels.