Technology Research On Diesel Engine Speed Control System Based On Performance Of Disc Type Brushless DC Motor

In contemporary society, as more attentions are paid on environmental pollution and energy crisis issues, diesel engines are requested to be more economic, reliable and have less noxious emissions. The conventional mechanical control of diesel engines cannot satisfied these requirements. The electronic control of diesel engines has characteristics of more accurate and flexible control, faster response and higher adaptability, so the diesel electronic control is becoming the cutting edge of diesel technology.The actuator of diesel electronic speed control system is one of the major components of control system. Based on the requirements of actuator, such as high efficiency, low consuming-high driving power, high responding speed, limited fitting room, this thesis chooses the Disc Brushless DC Motor which is specially designed for limit fitting room. The structural arrangement in the longitudinal direction of BLDCM is tight, and its driving force is big. so it is suitable for implementing instrument. In this thesis, a digital control system which can accurately and real time control is designed based on BLDCM is designed. This system adjusts the rack positions of oil pumps through BLDCM as so to control diesel engine speed.Under Matlab/Simulink. the whole speed-adjustment model is built application based on the operation principle of diesel engine and control actuator of BLDCM. Combining the strength of traditional PID control (high adaptability) and fuzzy control algorithm (small control error in steady state), an intelligent fuzzy self-tuning PID controller was developed. The results show the great improvement of the BLDCM control performance in dynamic and steady state, especially increasing the system response speed and control accuracy.With a hardcore of TMS320F2812. this thesis completes the design of software and hardware control systems, including the driving circuits of Disc type BLDCM. signals acquisition circuits for the speed, current and position of motor, and for the speed and the protect of diesel engine. The idea of modularization software design is adopted in order to improve the transplantation and real time of the systems.The tests and experiments of different sub-modules and driving control module are presented in this thesis:simulation experiments based on Matlab/Simulink platform and CCS software system are also carried out. The results show that the experimental wave shapes comply with theoretical analysis. So the control system is proved to be feasible.