الفهرس | Only 14 pages are availabe for public view |
Abstract sis presented here describes a framework for optimal control by nonlinear ing via a parameterization of multi-input eigenvalue assignment, which only for distinct open and closed-loop eigenvalues but also for the case of open and closed-loop eigenvalues. This framework is used to develop a fJ,nd effective algorithm based on iterative optimization that can solve several ’,multivariable control problems. The algorithm is tlsed for designing a state matrix which minimizes objective functions based on the Frobenius norm of dback gain and/or the condition number of the c.losed-loop system state for specified closed-loop eigenvalue placement. The developed algorithm commercially available routines based on easy-to-use NAG routine for unconstrained optimization which are supported by error indicators. These s do not require the first derivatives of the objective function to be explicitly The effects of basing the above algorithm upon more sophisticated rehensive) routines than the easy-to-use routines are demonstrated. These es have additional parameters to the easy-to-use routines to allow the enced user to improve the efficienr:y of the optimization by tuning it to a ular problem. The use of such routines is to experimentally validate the use of sy-to-use routines and to seek better solutions to the ill-conditioned problems. ;mgorithm was tested on five test problems using routines for both Quasi-Newton :nonlinear least-squares optimization. Each with approximate and then accurate ”rs;on at each iteration. The algorithm presented is used to show by examples that .. izing the product of condition number of the closed-loop system and the state ack gain may result in a controller which is more robust to rounding errors in elements of the gain matrix than the controller which minimizes condition number e for the closed-loop system. The test problems indicate that, for robust control, ... may be more desirable to minimize the product of condition number and gain, .. ther than condition number alone. |