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arXiv · 1604.01981

Analysis of higher order time delay systems using Lambert W function

Niraj Choudhary·Janardhanan Sivaramakrishnan·Indra Narayan Kar
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Abstract

In this note, analysis of time delay systems using Lambert W function approach is reassessed. A common canonical form of time delay systems is defined. We extended the recent results of [6] for second order into nth order system. The eigenvalues of a time delay system are either real or complex conjugate pairs and therefore, the whole eigenspectrum can be associated with only two real branches of the Lambert W function. A new class of time delay systems is characterized to extend the applicability of the above said method. A state variable transformation is used to transform the proposed class of systems into the common canonical form. Moreover, this approach has been exploited to design a controller which places a subset of eigenvalues at desired locations. Stability is analyesed by the help of Nyquist plot. The approach is validated through an example.

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Niraj Choudhary, Janardhanan Sivaramakrishnan, Indra Narayan Kar. 2016-04-07. Analysis of higher order time delay systems using Lambert W function. https://doi.org/10.1115/1.4036874

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