Optimal Control for Bouncing Suppression of CNG Injectors

Abstract

This paper describes the model-based design and the experimental validation of a control system which suppresses the bouncing behavior of Compressed Natural Gas (CNG) fuel injectors. First a detailed model of the system is developed, including temperature and supply-voltage variation effects. Using an optical position sensor, this model is experimentally validated in a second step. Based on this model a feed-forward controller is developed and tested which minimizes the bouncing energy of the system. Since in series applications position sensing would be too expensive to use, an observer-based iterative control algorithm is derived which uses coil current measurements instead of the position information to asymptotically suppress bouncing.