# 관측기를 갖는 2자유도 서보계의 승법적인 불확실성에 대한 강인한 안정성

• 김영복 (부경대학교 제어기계공학과) ;
• 양주호 (부경대학교 제어기계공학과)
• Published : 1997.02.01

#### Abstract

In order to reject the steady-state tracking error, it is common to introduce integral compensators in servosystems for constant reference signals. However, if the mathematical model of the plant is exact and no disturbance input exists, the integral compensation is not necessary. From this point of view, a two-degree-of-freedom(2DOF) servosystem has been proposed, in which the integral compensation is effective only when there is a modeling error or a disturbance input. The present paper considers robust stability of this 2DOF servosystem incorporating an observer to the structured and unstructured uncertainties of the controlled plant. A robust stability condition is obtained using Riccati inequality, which is written in a linear matrix inequality (LMI) and independent of the gain of the integral compensator. This result impies that if the plant uncertainty is in the allowable set defined by the LMI condition, a high-gain integral compensation can be carried preserving robust stability to accelerate the tracking response.

#### References

1. Proc. 31st IEEE CDC A tow-degree-of-freedom design of optimal servosystem Y. Fujisaki;M. Ikeda
2. Trans. SICE v.27 no.8 Synthesis of two-degree-of-freedom servosystems Y. Fujisaki;M. Ikeda
3. 12th IFAC World Congress v.Ⅰ A tow-degree-of-freedom design method of LQI servo system, Part Ⅰ T. Hagiwara;T. Yamasaki;M. Araki
4. Trans. iSCIe v.4 no.12 A design method of LQI servo systems with two degree of freedom T. Hagiwara;Y. Ohtani;M. Araki
5. The 17th SICE Symposium on Dynamical System Theory Robust stability and and high-gain compensation of a two-degree-of-freedom servosystem Y. Kim;Y. Fujisaki;M. Ikeda
6. The 39th annual Conference of iSCIe On robust stability of two-degree-of freedom servosystem incorporating an observer M. Kobayashi;Y. B. Kim;M. Ikeda;Y. Fujiski
7. The 24th SICE Symposium on Control Theory High-gain compensation of a two-degree-of-freedom servosystem incorporating an observer Y. B. Kim;M. Ikeda;M. Kobayashi;Y. Fujisaki
8. Memoirs of The Graduate School of Science & Technology, KOBE Univ. v.14-B Robust stability of a two-degree-of-freedom servo-system with unstructured uncertainty Y. B. Kim;M. Ikeda;Y. Fujisaki
9. IEEE Trans. Automatic Control v.35 no.3 Robust stability of uncertain linear systems : Quadratic stability and $H_{\infty}$ control theory P. P. Khargonekar;I. R. Petersen;K. zhou
10. J. of SICE v.26 no.5 High-Gain feedback & robustness H. Maeda