Non-fragile H∞ controller for combustion process in rocket motors

The aim of this paper is to analyse the problem of robust non-fragile H∞ controller for the combustion process in liquid propellant rocket motors chamber. Based on the delay decomposition approach, the whole delay interval is divided into two equidistant subintervals and a new Lyapunov-Krasovskii functional (LKF) which contains some triple-integral terms and augment terms is introduced on each interval. By using L-K stability theorem, integral inequality method together with free weighting matrix approach, a new delay-dependent bounded real lemma (BRL) is formulated. Then, by applying the BRL, non-fragile H∞ controller is formulated in terms of linear matrix inequalities (LMI), where no any parameter needs to be turned and apt to realisation. Finally, simulation results are given to illustrate that the designed controller has good robust and non-fragile performance.