The Study On Load Regulation Of Hydraulic Braking Energy Regenerative System For Vehicle

In the braking process, the vehicle kinetic energy is converted into unrecoverable heat energy and wasted. The waste is serious especially in the urban bus, which carries a large number of passengers and brakes frequently. However, the hydraulic regenerative braking system converts the lost kinetic energy into hydraulic energy, which is stored in the accumulator. When needed, the hydraulic energy will be released and converted into the kinetic energy of vehicle. The low oil consumption and emission of vehicle are achieved by the way of applying the hydraulic regenerative braking energy system in the urban bus.In this thesis, the hydraulic regenerative braking energy system structure is designed and the scheme of load adjustment for regenerative braking energy system is proposed, on the basis of the analyzing the principle of hydraulic regenerative braking energy system. The performance parameters of the major equipments of system are matched with the LCK6850CHDD bus, produced by ZhongTong bus factory. The braking energy recovery process and the braking energy releasing process are studied, and then two 3D-MAPs are established to control the displacement of variable displacement pump/motor. One is established according to the barking force and the press of accumulator, in the braking energy recovery process, and the other is established according to the releasing force and the press of accumulator, in the braking energy releasing process. The circuit and program of electric control system are designed. The braking energy recovery process and the braking energy releasing process are simulated with Matlab, and the numerical results show that the system has higher braking energy recovery rate, release rate and regeneration rate.