Optimal non-fragile controller realization algorithm and application to control problems  

作　　者：Mian Ashfaq Ahmad 王道波 Ahmad Mian Ilyas 王宏强 

机构地区：[1]College of Automation Engineering,Nanjing University of Aeronautics and Astronautics [2]College of Automation Engineering, Nanjing University of Aeronautics and Astronautics [3]Dept.of Electrical and Electronic Engineering,Imperial College London

出　　处：《Journal of Harbin Institute of Technology(New Series)》2010年第1期89-94,共6页哈尔滨工业大学学报（英文版）

摘　　要：To reduce the fragility encountered in controller implementation, which is a measure of extent to describe small perturbations in controller parameters caused by rounding-off errors or component tolerances, and keep the system stability and performance, approaches of weighted eigenvalue sensitivity and stability radii comparison were used for computation and reduction of controller fragility. An algorithm has been derived for the efficient reduction of controller fragility, which used eigenstructure decomposition to obtain the suboptimal solution. The algorithm was tested for different control problems through reducing their fragility by a large margin. Different canonical forms were analyzed for fragility, including controllable canonical form, observable canonical form, modal canonical form, balanced realization and optimal (non-fragile) form. Different realizations were implemented through C language Matlab EXecutable (CMEX) S-function discrete state space block. Double precision calculations were performed. Open and closed loop controller realizations were compared with simulink state space (optimal) block. Results of comparison indicate that the optimal non-fragile controller realization shows better results both in open loop and closed loop realization.To reduce the fragility encountered in controller implementation, which is a measure of extent to describe small perturbations in controller parameters caused by rounding-off errors or component tolerances, and keep the system stability and performance, approaches of weighted eigenvalue sensitivity and stability radii comparison were used for computation and reduction of controller fragility. An algorithm has been derived for the efficient reduction of controller fragility, which used eigenstructure decomposition to obtain the suboptimal solution. The algorithm was tested for different control problems through reducing their fragility by a large margin. Different canonical forms were analyzed for fragility, including controllable canonical form, observable canonical form, modal canonical form, balanced realization and optimal （non-fragile） form. Different realizations were implemented through C language Matlab EXecutable （CMEX） S-function discrete state space block. Double precision calculations were performed. Open and closed loop controller realizations were compared with simulink state space （optimal） block. Results of comparison indicate that the optimal non-fragile controller realization shows better results both in open loop and closed loop realization.

关 键 词：controller fragility eigenstructure decomposition controller realizations 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置] TP13[自动化与计算机技术—控制科学与工程]