Designing of LQIG method for controlling the wastegate of a turbocharged diesel engine to increase engine output power using experimental results of engine test chamber laboratory

In this paper, first, using a test set on a turbocharged diesel engine in the engine test room, a nonlinear model is obtained and it is linearized around several operation points. Then, for the linear models, a linear quadratic integral Gaussian controller (LQIG) with variable parameters as function of engine speed is designed and simulated. In the proposed method, by controlling the wastegate, the boost produced by the turbocharger can be controlled at all engine speeds (especially the lower and middle speeds) with high performance response, thereby improving the output power and engine torque in all speeds. The closed loop control system is simulated and evaluated in the presence of noise and model uncertainty. The simulation results show the better performance and higher robustness in comparison with PID and LQR controllers.