Optimal control of an internal combustion engine and transmission system

The control of an internal-combustion engine such that it will produce its required output, with a minimum consumption of fuel, even in the presence of random load disturbances, has become a necessary requirement for future prime-mover and vehicular applications. This thesis is concerned with an attempt to produce a practical scheme to meet that requirement from a study of several methods of achieving optimal engine regulation and a method of obtaining optimal start-up. An attempt was made first to identify the response of the engine-transmission-load combination with a mathematical model obtained by the use of computers. The servo-mechanism associated with the throttle was identified also, and then a complete state-variable description of the system was obtained. Next an automatic gear-changing scheme was designed and implemented. With the availability of this practical system an optimal control function was generated then to implement optimal start-up. The optimal function was calculated by solving the associated multi-point boundary value problem by means of technique of quasi-linearisation. To subject the system to random loads an artificial road was simulated, and a scheme was devised to vary the dynamometer loading in response to this 'road' signal. The remainder of the thesis is concerned with a study of several different methods of obtaining optimal or sub-optimal schemes of regulation and with comparisons of experimental results and the results from associated theoretical computer studies. Many suggestions for further investigations are contained in the final chapter.