Research On Energy Recovery Efficiency Of Hydraulic Hybrid System

Many national governments are paying more and more attentions on the hybrid cars with the shortage of energy. And hydraulic hybrid vehicles have good performance in improving vehicle fuel economy, safety, etc, while electric hybrid vehicles have the disadvantage of such as low cruising power, increasing vehicle’s weigh. So in the current with many key technology can not been solved on the electric hybrid vehicles, Focusing on the study of hydraulic hybrid vehicles is a good choice.The object of this paper is a parallel hydraulic hybrid vehicle. Using the method of joint simulation after modeling the vehicle and the hydraulic regenerative system, then researching and analyzing of the effects of parameters of main components of the hydraulic system on the recycling energy of hydraulic accumulator. Finally using the bench test to validate the results of simulation. The main work in this paper is shown below.(1) Comparing analyzing the working mechanisms of various hydraulic hybrid system, as well as their advantages and disadvantages. Finally determining the types of power system and structure of the hybrid system. Then analyzing and calculating the main components, such as hydraulic accumulator, hydraulic pump/motor, and then determine the correct model.(2) Analyzing the force on the overall vehicle, especially focusing on the force situation of wheel. Setting appropriate braking force distribution coefficient according to the ECE braking regulaions with the goal of operation safety, energy recovery maximization. Finally designing the scheme of control strategy and distributing the hydraulic braking torque and friction braking torque effectively.(3) Respectively building the vehicle model and hydraulic model of regenerative brake system in ADAMS/Car and MATLAB/Simulink. Realizing the combination simulation of the two software and based on this designing scheme of control strategy aiming to distribute the hydraulic braking torque and friction braking torque effectively.(4) Validating the effects of parameters of hydraulic accumulator, hydraulic pump/motor on the recycling energy of hydraulic accumulator independently and by the method of orthogonal test. Finally validating the result of simulation by bench test.