Forward Modeling And Simulation Of Parallel Hydraulic Hybrid Vehicle

The environmental pollution and energy shortage have become serious problems facing mankind today. Develop energy-efficient and clean automobiles break no delay. The hybrid vehicles have the best prospect of industrialization. The hydraulic hybrid vehicles as one of the hybrid vehicles have an advantage of higher power density, ability to accept the high rates and frequencies of charging and discharging, both of which are favorable for energy storage and release requirements. So they have the most broad prospect for development.Referring to a large amount of related records at home and from abroad, this dissertation uses automated mechanical transmission based on the parallel hydraulic hybrid vehicle as research object, establishes the vehicle forward simulation model, and makes an intensive study on the energy utilization strategy of hydraulic hybrid vehicle.After studying the principle of the hydraulic hybrid vehicle, the author compares the structure of the backward and forward simulation, establishes the forward simulation model according to the task. The driver model is the main module of the forward simulation that different from the backward model, which makes clear that the driver model plays an important role in the forward structure. In view of the deviation between the actual speed and the desired speed, the author uses the PID controller and fuzzy logic controller to amend. The simulation results show that fuzzy logic control effect of the driver model has better speed tracking than with PID control model.Based on the nonlinear components of the clutch and the AMT transmission, the article establishes the AMT gearbox model and the automatic clutch model in the MATLAB/Simulink platform, analyzes the clutch dynamic sliding friction, establishes the work state of the module and the control mode module of the clutch. After that, the author establishes other models of the hydraulic hybrid vehicles, such as the wheel model, the engine model, the hydraulic accumulator model and the hydraulic pump/motor model and so on.On the basis of analyzing the energy utilization strategies, the author uses the active charge pump to adjust the rate of the engine load, which makes the engine work in the high area. The paper studies the logic threshold control strategy, fuzzy logic control strategy of the parallel hydraulic hybrid vehicle, compares the control effect of the two controllers. The simulation results show that the fuzzy logic control strategy distributes the engine and the hydraulic pump/motor output torque more reasonably, and the working points of the engine focus on the topics of the best fuel economy neighborhood.