Design of an H/sup infinity / optimal controller by using DGKF's state-space formulas

摘要

The two-Riccati-equation method was employed to design an H/sup infinity / optimal controller for a four-block problem. An iterative scheme was used to reduce gamma to a number which is very close to the optimum. However, as gamma approaches the optimum, the elements of the state-space realization of the controller approach infinity. It is demonstrated that the numerical difficulty is caused by the restriction of the controller's being strictly proper. This difficulty can easily be removed by the use of a proper controller with a direct feed-through term.