Extensions of Retrospective Cost Adaptive Control:Nonsquare Plants, and Robustness Modifications.

[摘要] Controllers that have adjustable parameters, and an update law for adjusting these parameters,are called ``adaptive controllers;;;;. Adaptive controllers typically entail assumptions aboutthe dynamic order, relative degree or transmission zeros of the system, and may not be applicable to systems that are not positive real, passive, or minimum phase. In 1980s, the fragility of adaptivecontrollers to violations in these assumptions has been demonstrated through various counterexamples. This motivated the development of robustness modifications for adaptive controllers, which is the main goal of this dissertation.In this dissertation, we focus on retrospective cost adaptive control (RCAC), which is a direct, digital adaptive control algorithm. RCAC is applicable to MIMO, nonminimum-phase (NMP) systems, but it assumes that the NMP zeros ofthe plant, if any, are known.The main contribution of this work includes theory and analysis for retrospectivecost adaptive control of nonsquare systems and development of a modified, robust RCACupdate law for maintaining stability and convergence in the presence of unmodeledNMP zeros.

[发布机构] University of Michigan

[效力级别] Nonsquare Systems

[关键词] Adaptive Control;Nonsquare Systems;Robust Adaptive Control;Aerospace Engineering;Electrical Engineering;Mechanical Engineering;Engineering;Science;Aerospace Engineering