# ROBUST STABILITY ANALYSIS OF SINGULARLY PERTURBED MAGNETIC SUSPENSION SYSTEMS

### Nan-Chyuan Tsai, Chien-Ting Chen

#### Abstract

For a singularly perturbed magnetic suspension system, two kinds of state feedback controllers are synthesized to account for the inherent instability of the open-loop plant with two-time-scale properties. Kharitonov polynomials, extremal vertex and uncertain Nyquist plot are employed to examine the maximum tolerance against system parameters uncertainties such that the stability of the closed-loop system is still retained. Experimental simulations are reported to illustrate the robustness of designed controllers both in stability and performance. At last, Interlacing Theorem is introduced to analyze the stability of uncertain suspension systems via the characteristic interval polynomials. It is found that identical results are obtained, in comparison with extremal vertex approach.

#### References

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#### Paper Citation

#### in Harvard Style

Tsai N. and Chen C. (2005). **ROBUST STABILITY ANALYSIS OF SINGULARLY PERTURBED MAGNETIC SUSPENSION SYSTEMS** . In *Proceedings of the Second International Conference on Informatics in Control, Automation and Robotics - Volume 3: ICINCO,* ISBN 972-8865-31-7, pages 166-172. DOI: 10.5220/0001188001660172

#### in Bibtex Style

@conference{icinco05,

author={Nan-Chyuan Tsai and Chien-Ting Chen},

title={ROBUST STABILITY ANALYSIS OF SINGULARLY PERTURBED MAGNETIC SUSPENSION SYSTEMS},

booktitle={Proceedings of the Second International Conference on Informatics in Control, Automation and Robotics - Volume 3: ICINCO,},

year={2005},

pages={166-172},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0001188001660172},

isbn={972-8865-31-7},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the Second International Conference on Informatics in Control, Automation and Robotics - Volume 3: ICINCO,

TI - ROBUST STABILITY ANALYSIS OF SINGULARLY PERTURBED MAGNETIC SUSPENSION SYSTEMS

SN - 972-8865-31-7

AU - Tsai N.

AU - Chen C.

PY - 2005

SP - 166

EP - 172

DO - 10.5220/0001188001660172