Mass flow rate control of solenoid-based injectors

Abstract

This paper presents a mass flow rate control method for solenoid-based injectors in open-loop, i.e. without physical sensor feedback. Measuring the mass flow rate in injectors is important because the performance of the injector determines fuel consumption and emissions. While it is possible to perform this control using different types of sensors, this would increase the cost and reduce the reliability. With this study, it was aimed to control the mass flow rate of solenoid-based injectors using continuous switching control to regulate the injector’s needle displacement without using sensors. For this purpose, a solenoid-actuated injector prototype was created. Model-based estimators were used to determine the states of the injector, while a super-twisting sliding mode controller was used to track the desired mass flow rate references. The results of the experiments showed that tracking for sinusoidal, triangular, and square trajectories yielded a mass flow rate percent error of less than 1.06. The proposed open-loop control algorithm can be used to track different mass flow rate references in internal combustion engines.