The Research Of Engine Electronic Governor Based On TMS320F28335

Speed governor is a device to maintain speed stability automatically. The gas source which is provided to internal combustion engine is unstable in the run time. When the gas source changes constantly, the speed of engine will also change. The voltage and the frequency are influnced by the speed, if the speed is unstable, AC voltage and frequency which produced by generators are also unstable. Digital electronic governor can make the speed stably in order to produce high-quality power. So it is inevitable to develop a fast response, high precision digital electronic governor.This article describes one kind of digital electronic engine control system based on tms320f28335. Overall system architecture is designed. The system adopts double closed-loop control system, speed adjustment is the outer control, valve position adjustment is the inner loop control. The speed control system includes six parts:LCD display, speed detection, valve position detection, fuzzy PID adjustment of speed, fuzzy PID adjustment of valve position, valve position control (DC motor speed control)PID controller, fuzzy controller and fuzzy PID controller are designed. The simulation of speed control system will be done useing three different control strategies respectively by MATLAB/Smulink. From the result, the effect of the respective control can be compared, the feasibility of Fuzzy PID control can be verified, related parameters can be obtained. The effect of Fuzzy PID control is better than PID control and Fuzzy control. Fuzzy control and PID control will be combined, if the error is big, Fuzzy control will be used to relize fast control, if the error is small, PID control will be used to relize precise control. Fuzzy PID control algorithm improves dynamic response with load change, and keeps the adjuster working in a wide operating range.Experiment platform will be set up. TMS320F28335 is the master chip. It is used to observe working condition of the system, read the detected signal, achieve a variety of control algorithms, make each module working orderly. Hall sensor A04E is used to measure the speed of engine. DC motor is used as executive. L298N is used to drive DC motor. PWM is used to control DC motor.Program will be debugged in the environment of CCS. System program includes seven parts:Initialization module, LCD display, speed calculations, valve position detection, fuzzy PID adjustment of speed, fuzzy PID adjustment of valve position, duty cycle adjustment. Two interrupts are adopted, one is ECAP capture interrupt which is used to capture the rising edge of pulse, the other one is the periodic interrupt of timer T1 which can control the call of all the functions, and keep each module working orderly.