Design and Experimental Study on Fuzzy Self-Adaptive Controller of Common-Rail Pressure for DME Engine

Abstract

A fuzzy self-adaptive PID controller is developed for controlling the pressure of the common-rail of DME (Dimethyl Ether) engine, and the performance test was carried out on a pump test bench. The results showed that the lag time of pressure following was not more than 0.34ms when the set value of common rail pressure stepped under the different speed, and the fluctuation value of common-rail pressure did not exceeding 0.5MPa while the target pressure changed from 5MPa to 11MPa, and the rail pressure fluctuation decreases rapidly with the target pressure increased, and the rail pressure fluctuation value did not exceeding 0.1MPa when the target pressure reaches at 11MPa. All these results fully illustrated that the fuzzy adaptive PID controller possesses the common advantages of PID controller and fuzzy controller, and the regulator of common rail pressure has the advantages of fast response, small static error, tiny overshoot, good robustness and quite stability.