Experimental Investigations on Control Strategy of Regulated Two-Stage Turbocharging System for Diesel Engine Under Transient Process

The regulated two-stage (RTS) turbocharging system is considered to be one of most effective measures to meet the requirements of the higher power density and the higher speed of automobile and marine diesel engines. However, the turbocharger matching and boost pressure control becomes significantly complex due to the engine operating conditions changed frequently. The engine test bench was built up to investigate the effects of several control strategies on the dynamic performance of the diesel engine with the RTS system. For the transient state four different control strategies, the open-loop control, the conventional PID control, the variable-parameter PID control, and the fuzzy control were employed. The experimental results show that the designed fuzzy control strategy has the best dynamic performance and the stability for both the transient loading process with constant speed and the transient marine operating conditions. Under the transient loading process and constant speed, the response time of the fuzzy control strategy is 0.3 s faster than that of the variable-parameter PID control, and 2.8 s faster than that of the open-loop control strategy. Under the transient marine operating conditions, the response time of the fuzzy control strategy is reduced by 0.9 s than that of the variable-parameter PID control, and 5.2 s reduced than that of the open-loop control strategy.