Abstract:
Nowadays, the demand for energy savings and reduction of greenhouse gases as well as unhealthy emissions of automobile has been highly increased. Also as a result of the yearly rising of fuel prices and new environmental regulations of vehicle emissions; the development of new hybrid vehicles to reduce fuel consumption and emissions is a prerequisite. Hybrid vehicles have three different system configurations; series, parallel and series-parallel. These configurations can be divided into electric hybrid and hydraulic hybrid. Hydraulic hybrids operate basically the same way as electric hybrids, but they use a motor-pump unit instead of an electric motor-generator and a hydraulic accumulator rather than the battery pack to store recuperated energy. The electric hybrid has been promoted and successfully applied in various automobiles by industry. The high power density of hydraulic pumps/motors and hydro-pneumatic accumulators make hydraulic technology look promising for passenger cars and need be integrated in the vehicle industry due to its low price and recently developed units of high efficiency compared to electric machines. Aim of this paper is to introduce the development of using a Secondary controlled/ pressure coupling Hydrostatic Transmission (SC-HST) drivetrain to the new configuration of series hydraulic hybrid drivetrain which is called the Hydrid for use in passenger cars. A key component in the Hydrid drivetrain is the Innas hydraulic transformer and the new technology of using floating cup principle in axial piston hydrostatic pumps, motors and transformers which reveal a higher efficiency up to 98% [1]. Moreover one of the big merits of using the Hydrid drivetrain is its ability to force the engine to run only under high loads at all vehicle velocities.