Pitfalls of a least-squares-equivalent controller for linear, time-periodic systems
Pitfalls of a least-squares-equivalent controller for linear, time-periodic systems
复制标题
线性、时间周期系统的最小二乘等效控制器的缺陷
DOI:
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发表时间:
2001
期刊:
影响因子:
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通讯作者:
J. Angeles
中科院分区:
文献类型:
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作者:
P. Montagnier;R. Spiteri;J. Angeles
We review a technique for the design of controllers for linear, time-periodic systems. A major appeal of the technique, first proposed by Sinha and Joseph, is the use of Floquet-Lyapunov theory to transform the periodic system to a form where classical control strategies for time-invariant systems may be employed. However, it is normally impossible to find a completely time-invariant control system that is equivalent to the original time-varying system: Application of the Floquet-Lyapunov transformation in fact yields a time-varying control system that the technique makes equivalent to a time-invariant one in the least-squares sense, in order to subsequently synthesize the controller via pole placement using a constant feedback matrix. However, classical control and Floquet-Lyapunov theory clearly show that it is erroneous to conclude that the behaviour of the least-squares-equivalent, time-invariant system always matches the behaviour of the original timeperiodic system. Using an example found in the original paper, we provide a simple counter-example that illustrates the failure of the proposed strategy and an analysis of the reasons for its failure.