How Hybrid Cars Work
"Putting hybrid technology into our most popular model is a
further indication of Honda's commitment to hybrid technology and our confidence that consumers are ready for more hybrid models."
~ Tom Elliott, Executive VP, American Honda Motor Co., Inc.
Today's hybrid car is a combination of an electric motor with a gasoline-powered engine. In a gas-powered car, the heat energy achieved by the burning of gasoline powers the engine, which drives the transmission that rotates the wheels. In an electric car a set of batteries supplies energy to the electric motor that drives the wheels. In the HEV, there are three different designs - the series, parallel and split.
In the series hybrid, the internal combustion (IC) engine converts mechanical energy into electrical energy through the generator and the electric motor propels the car. The generator either charges the batteries or powers the electric motor, which drives the transmission. This type of configuration allows the IC engine to run at optimal revolutions per minute, offering greater performance as well as reduced energy expenditure and emissions. In addition, braking energy is salvaged and a minimum of energy is unused while the car is idling.
The parallel design varies from the series hybrid, because the IC engine connects directly to the transmission along with the electric motor and either can drive the wheels. According to different driving conditions, one motor or the other will take over, or both will operate. In general highway driving, the IC engine is at work, while the electric motor contributes power in acceleration, such as for climbing hills or passing cars. The electric motor also performs as a generator for braking and charging the batteries - known as regenerative braking. Unlike earlier test models, these HEVs never need to be plugged in between trips.
In the split hybrid the IC and electric motors each drive one axle, while there is no link between these components.
Neither the Honda Insight or Civic hybrid, nor the Toyota Prius fit these categories completely, however, they are closest to the parallel model. They each have an IC engine and electric motor connected to the wheels by the transmission. The IC engine shuts off at idle and the electric motor takes over, especially useful at low speeds and coasting. The electric motor, which draws its energy from a battery pack charged through regenerative braking starts the engine but generally cannot power the car alone. Although, the Prius can accelerate to 15 mph on electric power only, after which the gas engine kicks in.
Fuel economy is maximized through several features including: the electrically-operated power steering drawing power only when needed; the engine running at efficient speeds and loads; and a smaller, lighter engine and lightweight car body.
If this is all the information you want in order to understand hybrid systems, you can stop here. However, if you have a technical mind and would like to delve further into this ingenious technology, read on.
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