Gasoline Engine Electronic Throttle Control Method And Experimental Study

Electronic throttle is an important part of the engine management system.It changes the air flow into the engine to improve the dynamic performance and improve the emission performance.Although the traditional mechanical throttle responds quickly,it cannot achieve the optimal control of the throttle opening,and it is difficult to meet the requirements of today’s society in terms of safe driving and exhaust emission indicators.At the same time,the theory of wire control put forward the application of electronic control technology in automotive systems.The electronic throttle system is one of the electronic control systems used earlier in automobiles,which can effectively improve the driving performance of the vehicle and at the same time can achieve precise control of the throttle opening,which is conducive to the reduction of pollutant gas emissions and fuel consumption.This article selects the Bosch GF30 throttle valve as the research object,and makes a detailed analysis of the structure and working principle of the electronic throttle system.Non-linear factors in the electronic throttle system: friction torque,return springs,gear clearance,and intake disturbances are thoroughly studied.Based on the mechanism analysis method,an electronic throttle nonlinear mathematical model was established.Simultaneously complete calibration of various parameters in the electronic throttle system(motor parameters,spring stiffness,etc.)and calibration of the sensors(throttle position sensor and accelerator pedal position sensor).For the nonlinear problem of the electronic throttle system,the modern control strategy applied to the electronic throttle system was analyzed.Finally,PID control and sliding mode control were selected for comparative simulation research.The electronic throttle PID and sliding mode simulation models were built using Matlab/Simulink.The simulation result of the step signal shows that the overshoot of the electronic throttle system is zero regardless of PID or sliding mode control.However,the sliding mode control is shorter than the PID control rise time and the settling time.As can be seen from the sinusoidal and square wave tracking effects,the follow-up effect of the sliding mode control is also superior to the PID control.The hardware-in-the-loop simulation experiment was conducted using the electronic throttle simulation experiment platform to verify the validity and accuracy of establishing a non-linear mathematical model of the electronic throttle system.The electronic throttle simulation experiment platform used the Freescale MC9S12 single-chip microcomputer as the development board of the main chip,using Matlab/ Simulink builds a hardware-in-the-loop simulation model for sliding mode control of an electronic throttle system.The hardware-in-the-loop simulation results show that when a sliding mode controller is used,there is no overshoot in the system and the response speed is fast.Rise time and settling time are basically consistent with the model simulation results.Sliding mode control can well suppress the nonlinear factors of the electronic throttle system,and at the same time meet the requirements of fast and accurate control of the electronic throttle.However,in hardware-in-the-loop simulation,but electronic throttle system makes buffeting easily.