Abstract
We consider the achievable delay margin of a real rational and strictly proper plant, with unstable complex poles, by a linear time-invariant (LTI) controller. The delay margin is defined as the largest time delay such that, for any delay less than this value, the closed-loop stability is maintained. Drawing upon a frequency domain method, particularly a bilinear transform technique, we provide an upper bound of the delay margin, which requires computing the maximum of a one-variable function. Finally, the effectiveness of the theoretical results is demonstrated through a numerical example.
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Acknowledgements
This work was partially supported by Taishan Scholar Construction Engineering by Shandong Government and National Natural Science Foundation of China (Grant Nos. 61573220, 61573221, 61633014).
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Ju, P., Zhang, H. Achievable delay margin using LTI control for plants with unstable complex poles. Sci. China Inf. Sci. 61, 092203 (2018). https://doi.org/10.1007/s11432-017-9185-6
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DOI: https://doi.org/10.1007/s11432-017-9185-6