Command switching based multiobjective safety protection control for inlet buzz of scramjet engine

This paper investigates the problem of inlet buzz safety protection for a class of scramjet engine. A command switching based multiobjective safety protection control (CS-MSPC) method is proposed. Specifically, first, a control-oriented one-dimensional scramjet modeling is presented, including the steady-state and dynamic modeling as well as the characteristics analysis of inlet buzz. Second, the problem-solving framework of command switching control for scramjet inlet buzz safety protection is constructed, by which the trajectories of the given command can be adjusted to strike the right balance between performance and safety. Then, under the framework, a multiobjective robust controller is designed to guarantee the output tracking requirement of safety protection by using guaranteed cost and regional pole placement techniques. Moreover, based on the actual working mechanism of scramjet, a hysteresis command switching logic is developed. Finally, the scramjet engine control model is employed to demonstrate the effectiveness of the proposed whole control method.