| On the background of global environmental degradation and fuel shortage, developingnew energy source vehicle has been a essential way for global automotive industry to face thechallenge. The industry is undergoing a revolution to automotive powertrain technologynowadays. It is found that, plug-in hybrid electrical vehicle (PHEV) is a effective choice tosolve the problems of low energy density of power cell and short driving distance of EV, alsoit makes zero emission in urban area. By analyzing the structure of hybrid power system andits electromechanical coupling mechanism, to carry out creative design and applicationresearch of power coupling system of PHEV, is very significant for developing andindustrialization of PHEV product.In this paper, analysis and comparison of powertrain of normal HEV and PHEV are done.Based on the comparison in detail about structure and motion feature between two types ofpower coupling system, torque coupling and speed coupling, to further research in this studyfocus on choose the power coupling system in which torque coupling and speed coupling taketurns operate. According to the structure and motion feature of planet gears, aiming to lowertorque volume of motor which is the main power source, the form of powertrain‘s structureand parameters are determined.The design constraints and the design parameters of powertrain system are applied intothe new plug-in hybrid coupling system. After lectotype of main components, detailed designof powertrain and system parameters matching are done. All-electric range (AER) is definedaccording to statistical data of personal car daily usage. Besides, power-energy ratio (RP/E) isintroduced to analysis of powertrain parameters, which is helpful for system design. Bybroadly investigation about control strategy of PHEV, AER-focused control strategy is chosento apply in designed model, including engine speed control strategy, traction torque/powercontrol strategy, regenerative braking control and coupling system control.Finally，the physical model of PHEV in AVL Cruise is established and the overall controlstrategy is defined in MATLAB/Simulink platform, then collaborated simulations arepreferred by the two software. After that, the results of the simulations about cycle run, acceleration and climbing capacities are calculated. The results indicate that, power propertyof the model meets the design requirement. Besides, fuel economy improved distinctlycompared to the vehicles which fueled by oil, although there is a certain gap comparing toPrius and Prius Plug-in. |
