Abstract:
Gas-electric hybrid cars improve both the gas mileage and performance of the automobile. They are most effective when the batteries are fully charged, so the electric motor can take a large role in moving the vehicle. Unfortunately, in practice, the batteries tend to remain about two-thirds charged both in the city and on the highway. This results in the electric motor often not being utilized, especially when starting the car from a halt. A sequential two-stage turbocharger will improve performance and gas mileage. The smaller, more responsive turbocharger is connected to an electric generator, sending electricity to the batteries whenever the engine is running. A wastegate on the turbocharger is utilized to keep the generator from spinning too rapidly. The second, larger turbocharger is connected to an air compressor, as in a standard turbocharger, so when more horsepower from the gasoline motor is required it will be available. Some possible results of this improvement: 1) Fewer batteries may be required, because the vehicle can be designed to use electric power all the time. The batteries can be sized for what's required to re-start the car from an auto-stop and to get the car moving from a stop. This will result is a much lighter car with better storage space and better gas mileage. 2) The vehicle can be built with a larger electric motor, so it takes a larger responsibility for moving the car. This allows a smaller gas motor for the same total horsepower, resulting in a lighter car with better gas mileage.