Hybrid electric cars have been very popular in the past few years and the most popular of them all is the Toyota Prius. The Toyota Prius has many features that has been developed in the past few years that are incorporated to reduce the smog emissions from their cars, which makes hybrid cars save fuel such as regenerative braking, hybrid synergy drive, and a internal combustion engine.
The Toyota Prius uses regenerative braking which is a mechanism that captures some of the energy used from braking and is sent back to the car’s electrical power for further use. Traditional braking methods use friction to slow the momentum of a car. In regenerative braking, the electric motors reverse its direction and the torque created go against the forward momentum created to stop the car. Although energy is still lost because of it, some of the wasted energy is collected and put back into the system.
The hybrid synergy system replaces a normal geared transmission with a electromechanical system, which does not run when the car is starting up. The motor-generator uses battery power to startup the car instead. That way, the car can stop and have the engine turned off during traffic on a freeway, saving gasoline. Ideally, a car equipped with a hybrid synergy system can be driven for a few miles without gasoline in case of an emergency to get to a gas station. With the performance of the Prius, it has a modest acceleration but has an extremely high efficiency for the size of the car. The hybrid synergy drive adds a dc to converter to also boost the battery potential to 500 V or more.
The Toyota’s internal combustion engine is an engine, which mixes and fuel and air to create high temperature and pressure to get the pistons in the engine moving. The designers of the Prius decided to use the Atkinson-cycle, which is a four stroke cycle which allows the intake valve held open longer than normal to allow reverse flow of intake of air into the intake manifold. This allows for more efficiency, which is why this is the choice of engine of hybrid vehicles. Because the car is gasoline electric, the engine of the Toyota Prius is smaller than compared to a car with a V-8 engine such as a Mustang or a Camaro. The performance would be the same on a normal freeway, but on a hill or a steep incline, the electric motor will assist the gasoline motor to push of the hill, using less gasoline to the same amount of work. It is also statistically shown that even with a car with huge horsepower; it is used less than 1 percent of the time. So, hybrid cars such as the Prius have a smaller engine to match the average power used by a driver.
The power split device is a patented feature that sets the Prius apart from the rest of the hybrid cars that are on the market. During low mileage, the car only uses electricity until it goes over 40 mph like for instance on a freeway, then the gasoline in the car will do the extra work necessary to accelerate the car, with all of the electricity coming from the generator. Because of that, the Prius never has to be recharged because the on board generator maintains the proper level of power at all times.
Among its features, advanced aerodynamic features on the car reduce the overall drag of the car. The Toyota Prius and several other hybrids have air blowing over them in a smooth manner. Improving the frontal appearance is the most obvious way to reduce the drag of the car. Low resistance tires are also a feature that was included, reducing drag about 50 percent. Also, using lightweight material in certain parts of the car also lighten up the overall weight of the car to have it go faster.
1. Karim Nice and Julia Layton “How Hybrid Cars Work”
2. Michael Pollick “What is Regenerative Braking?”
3. Matt Keveney “Atkinson Engine”
4. Bill Siuru “Synergy Drive: Why Toyotas Hydrids Rock”