Thrust and propellant mixture ratio control of open type LPRE using Q-ILC

LPRE(Liquid Propellant Rocket Engine) is one of the important parts to control the motion of rocket. For operation of rocket in error boundary of the set-up trajectory, it is necessary to control the thrust of LPRE according to the required thrust profile and control the mixture ratio of propellants fed into combustor for the constant mixture ratio. It is not easy to control thrust and mixture ratio of propellants, since there are co-interferences among the components of LPRE. In this paper, the dynamic model of LPRE was established, dynamic characteristics were analyzed with control system as PI control and PI+Q-ILC(Iterative Learning Control with Quadratic Criterion) control. From the analysis, it was confirmed that PI+Q-ILC control logic is more useful than simple PI control for control of LPRE.