Abstract: In rank one control algorithm regarding to engine air system control, the stringent condition to choose setpoints limits its use, an improvement strategy is developed, whose optimized target is to maximize power. The characteristic experiment of air path is made on the new setpoints chosen by the improvement strategy. The results show that the rank of the linearization transfer function on the new setpoints is deficient, and rank one control algorithm still can be applied. To survey the control effect of the improvement strategy, the design of rank one controller is completed, and the control effect is compared with that of individual closed-loop control by an experiment. The experiment results show that rank one control algorithm obviously surpasses individual closed-loop control during transient phases, and achieves the design objective, which proves that the improvement strategy to choose setpoints is successful.

Key words: Air system, Diesel engine, Exhaust gas recirculation, Rank one control algorithm, Variable nozzle turbocharger