Research And Development Of The Electronic Throttle Control System Based On Fuzzy-PID

Since the electronic throttle product was developed in the eighties of the twentieth Century,it has gradually been applied to high-grade automobile.Relative to the traditional mechanical throttle,the electronic throttle control system can sense the drive intention from the driver and the current situation of the auto,and then decide the correct throttle's position,so that the dynamic performance and fuel economy can be improved.Furthermore,it's helpful to realize some electronic control function,such as IDL,ASR and CCS,thereby the security and driving comfort can be improved.With the appearance of hybrid vehicle,electronic throttle becomes an inevitable choice for the power control and management for hybrid vehicle.In this paper,the electronic throttle control system was researched and developed, which laid the foundations of applying the ETCS to vehicle.The principle and basic structure of the electornic throttle control system(ETCS) was analyzed.The nonlinearity characteristics including nonlinear spring,aerodynamic impact,coulomb and viscous friction in the mechanical part of the throtle body was studied too.After the analysis of the ETCS,the key parameters of the throttle was 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 owing to nonlinearity factors of ETCS,a new Fuzzy-PID multiple compound control method is proposed.The robust dynamic characteristic of ETCS is attained by fuzzy control and the static performance is ensured by intelligent integral PID control, while switching process between two control methods is improved by using weighting factor function.Based on the Matlab/Simulink,the ETCS simulation model was developed.The main microchip of the electrionic throttle controller is MC9S12DG128 which is manufactured by Freescale.In this paper,the power supply module,DC motor's PWM drive module,serial communication module,CAN bus communication module and so on,was designed.The software,which is programmed with CodeWarrior software,for,microcontroller,accomplished,control,function,and,serial,communication function. In order to display the state of the system in real time and give an alarm when malfunction occurs,serial communication system based on LabWindows/CVI was designed. The results of the simulation and experiments show that the Fuzzy-PID multiple compound 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 and intelligent integral 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.