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A robust model reference adaptive control without strictly positive real condition. (English) Zbl 1051.93055
Using bounded external excitation and randomly varying truncation techniques, the author proposes a design method of a model reference adaptive controller for systems with unmodelled dynamics dominated by a small constant multiplied by a quantity dependent on the input, output and noise. He shows that the closed-loop system is globally stable, the estimation error for the parameter contained in the modelled part is of order of the mentioned small constant, and the closed-loop system under the modelled reference adaptive control law is suboptimal, while the strictly positive real condition (usually used) is replaced by a stable polynomial.
MSC:
93C40Adaptive control systems
93D21Adaptive or robust stabilization