Extended Definition of Hybrid Car Technology

The hybrid car has been developed during the past decade as a combination of the traditional automobile, which uses a gasoline engine, and the electric car, which derives its power solely from a charged electric battery/electric motor system. Many consumers are finding that hybrid cars strike an ideal balance between the two alternatives; it is more environmentally friendly and fuel efficient than a traditional vehicle and does not require the inconvenience of battery charging via a wall plug, as electric cars do. My objective in this report is to form a technical definition of hybrid car technology, in particular the mechanical and electrical workings of the hybrid automobile.

Given rising petroleum/diesel gasoline prices, the demand for alternative fuel vehicles, or vehicles that use other methods to obtain power, has increased dramatically in the past decade. These alternative fuel vehicles include electric cars, biodiesel cars, and of course, hybrid cars. The hybrid car is unique because the system contains both a rechargeable car battery and a small gasoline engine; the car battery is recharged while the car is running on the gasoline engine. Below you will see the Toyota Prius dashboard energy monitor, which contains a diagram of the Toyota Prius energy sources and consumption. This monitor diagram depicts the flow of the power from the battery to electric motor to the wheels; the other route is directly from the small gasoline engine. Using this monitor, the driver knows where the power for the car is coming from, the amount of battery power left, and when the battery is recharging.

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In order to understand the functioning of a hybrid vehicle, one must first know the mechanical components and their functions. These are as follows:

• Gasoline engine: traditional power source, except smaller and more efficient than in traditional vehicles
• Fuel tank: storage of energy (fuel) for the gasoline engine
• Battery pack: rechargeable storage of electrical energy
• Electric motor: draws energy from the batteries to accelerate the car; also sends energy back to the batteries when the car is slowing down.
  
• Generator (only on some models): produces electrical power and aids the electric motor
• Transmission: switches gears as speed varies, similar to a traditional transmission

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There are two types of hybrid cars, parallel hybrids and series hybrids. These classifications are based on the arrangement of the parts previously described.

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Parallel hybrids: These hybrid cars have two different circuits from which their power is derived. One pathway originates from the fuel tank, which activates the engine, which powers the transmission; the other originates from the electric battery pack to the electric motor, which also powers the transmission. These two pathways do not intersect in a parallel hybrid. The transmission then transfers power to the wheels. Most hybrid cars today are powered with a parallel system. Examples of parallel hybrids include the Honda Insight and Toyota Prius.

Series hybrids: Series hybrid cars generally have a generator act as the mediator between the engine and the batteries/electric motor. Therefore, the gasoline engine is not connected directly to the transmission. In this scenario, the flow chart begins with the fuel tank, which activates the engine, which transfers energy to the generator. The generator then is connected to the battery pack and the electric motor, and the electric motor provides power to the transmission and ultimately the wheels. Examples of series hybrids include the Saturn Vue Green Line and Honda Civic Hybrid.