A Frequency Method for the Design of Linear Suboptimal Controllers for Time Invariant System with Structural Constraints

In this paper a general approximate frequency method is intuitively developed for the design of suboptimal controller for the time invariant linear system under the structural constraints, in which the feedback gains of the suboptimal controller is obtained from the optimal controller of the corresponding reference system without structural constraints. The method is simple and robust in computation. It has been adopted for the optimization of vehicle suspension system and has been proved to be very time efficient as compared to the previously used nonlinear programming method.