Simulation Research On Dynamic Characteristic Of Clutch Actuator Of Hybrid Electrical Vehicle

Energy resource is the driving force for social development, and environment is the carrier for mankind's survival. Traditional vehicles have a larger amount of fuel consumption, and their emission can't make people satisfy. Thus, one day the oil resources will dry up, and the increased air pollution will result in crisis of survival. Hybrid electrical vehicle uses different energy conversion devices as power source, so it has incomparable advantages on the area of fuel consumption and emission. In Japan, America, German, and other developed countries, many governmental departments, automobile company, and related parts manufacturers give a high investment on the research and development of hybrid electrical vehicles. And some hybrid electrical vehicles have become products in the market.It is forecasted that our country will need import 0.36 billion tons oil, but domestic output is only 0.2 billion tons, so our country will need import 0.16 billion tons. That's to say, 45% oil of our demands will rely on import. To our country, the more we rely on the import, the more prominent our country's energy security problem will be. So, our country has increase the investment on HEV. The 10th Five-Year Plan, the 11th Five-year plan, and the 863 project all attach great attention on HEV.The major automobile companies all take this opportunity to launch their own HEV project. Zhejiang Geely Automobile Research Institute and Automotive Engineering Institute of Jilin University jointly launched a hybrid project. In the powertrain of the hybrid, there is an additional clutch. So there exists a problem about the engagement of the new clutch in the project. This paper did many investigations of the characteristics of various clutch actuators, and then focuses on thefollowing aspects: the design programs of the actuator, the structure of the actuator, and the performance simulation of the actuator. 1 First the current problems faced by the auto industry were analyzed, and the advantages that the hybrid vehicle compared with the traditional automobile was pointed out, thus the necessity to develop hybrid is obvious. And then the structure of hybrid electric vehicle was analyzed, and the structure form of the Geely hybrid was given, thus the content of this paper was emerged. Meanwhile, the current research situation of automatic clutch was analyzed, which will contribute to the later program design of the clutch actuator.2 The structure and characteristic of diaphragm spring clutch was analyzed, and then the force-deformation relation was obtained. The characteristic of the additional clutch was gotten after the clutch parameters had been put into the formula. Those helped to the design of the clutch actuator and simulation.3 The final plan was chosen. Then the motor form was selected, and the structure of the lever was analyzed, also it was pointed out that bending bar form is better than straight form. Finally, the structure parameters of the lever machine were optimized, and a 3D CATIA simulation model was built, also kinematic analysis of the clutch actuator was done.4 The motor model was established, and the inertia of motor flywheel and the time constant were calculated. Then energy conservation principle was used to converge all the inertia of the actuator at the motor axis. And PWM was used for motor controlling, and PID control strategy was used to optimize the motor response speed. Then, according to the structure of the clutch actuator, the Simulink simulation model was built. Combined with the characteristic of the diaphragm spring, the simulation about disengaging the clutch was done and the Separation process was very quick. Meanwhile, the simulation analysis of the characteristic about the actuator model following the displacement curve was given, which provided a basis for predicting the characteristics of the clutch engagement.5 The clutch engagement process was analyzed, and the impact factor and evaluation criteria of the engagement process were presented, also the simulink model of the whole car was built. The best displacement curvewas inputted to look the influence that the dynamic characteristic of the clutch actuator on the characteristic of the engagement process. In the end, the comparative analysis with experimental data was given. According to the experiment, it is obvious that the clutch actuator is feasible. Meanwhile, it can be seen that the clutch actuator had good performance from the result of the actuator model simulation. Also it can be seen that the clutch actuator could implement the control instruction very well while it did not have great impact on the performance of the engagement process from the result of the whole car model simulation. Finally, the experiment testified the validity of the simulation model.