Simulation And Experiment Research Of The Electronic Throttle Control System

With the developing of automotive electronic control technology rapidly, the vehicle performance requirements is raised, and people pay more attention to energy and environmental issues, so electronic throttle control system is widely used in many applications. The electronic throttle product was developed in the eighties of the twentieth century, and it has gradually been applied to high-grade automobile. Relative to the traditional mechanical throttle, electronic throttle system is a flexible control system. Because the throttle is driven by the motor, the electronic throttle's moving is fast and precisely.The principle and basic structure of the electronic throttle control system (ETCS) was analyzed. The nonlinearity characteristics, including nonlinear spring, aerodynamic impact coulomb and viscous friction in the mechanical part of the throttle body were studied. After the analysis of the ETCS, the key parameters of the throttle were measured. The numerical model of the electronic throttle control was built up.In order to adapt the swift dynamic characteristics of ETCS and restrain influence on control performance resulting from nonlinearity factors of ETCS,a Fuzzy-PID control method is proposed. The robust dynamic characteristic of ETCS is attained by fuzzy control. Based on the Matlab/Simulink, the ETCS simulation model was developed.In this thesis, the main microchip of the electronic throttle controller is MC9S12XS128 which is manufactured by FreeScale. The power supply for motor's PWM drive module was designed. The software, which is programmed by Code Warrior software for microcontroller, is accomplished for control function.The results of the simulation and experiments show that the Fuzzy-PID control method can exactly control the throttle's position, the overshoot is reduced, the transient tracking error is small and the hysteresis is short, while the PID control method don't work well. So the ETCS's controller which was developed based on Fuzzy-PID control strategy can meet ETCS's function requirements.