Abstract
The hydraulic hybrid system consists of four main components: the working fluid, reservoir, pump/motor (in parallel connected hybrid system) or in-wheel motors and pumps (in series connected hybrid system), and accumulator. In some systems, a hydraulic transformer is also installed for converting output flow at any pressure with a very low power loss. For further study the working developed power by the hydraulic installation of the hybrid hydraulic vehicle, two different premises were considered: serial and parallel connection of the recovery cylinders of the shock absorbers energy recovery system. To determine the optimum working parameters, numerical simulations were made using AMESIM software, by virtual modeling the recovery system. The main output working parameters are: the recovered driving speed, pressure in the hydraulic circuit, the flow and the effect on the damping process. As a general results, it can be observed, that the way how the shock absorbers are connected has a major influence on the performances of the recovery process. In order to get an answer to the problem of recovering shock absorbers connection type, series and parallel connection was analyzed. The optimum solution from the results of the simulations is considered the parallel connection of the recovery cylinders.
Keywords: alternative propulsion, hydraulic hybrid, energy recovery, serial and parallel connection, one way valve.