Design and implementation of an optimal gain scheduling controller for a diesel engine

A generalized gain scheduling control mechanism based on H₂ optimization techniques has been developed for a 2-cylinder water cooled Diesel engine. First, a set of linearized models is obtained for the engine operating at 3 different speeds and total of 15 loading conditions. It has been found that the behavior of the engine can best be characterized by a set of 5th order difference equations with appropriate time delays. The optimal controllers with a PID structure are then synthesized based on these mathematical models using off-line numerical optimization to minimize the H₂ norms of the closed loop sensitivity functions. The designed control system has been implemented, and experiments have indicated that the performance of the Diesel engine with optimal controllers is much superior to that of the engine with the existing mechanical governor in terms of speed regulation, and disturbance rejection. Experiments have also been conducted to evaluate the fuel efficiency of the engine with the optimal controller results are also presented in the paper