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arXiv · 2101.02859

Disturbance Observer

Hyungbo Shim
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Abstract

Disturbance observer is an inner-loop output-feedback controller whose role is to reject external disturbances and to make the outer-loop baseline controller robust against plant's uncertainties. Therefore, the closed-loop system with the DOB approximates the nominal closed-loop by the baseline controller and the nominal plant model with no disturbances. This article presents how the disturbance observer works under what conditions, and how one can design a disturbance observer to guarantee robust stability and to recover the nominal performance not only in the steady-state but also for the transient response under large uncertainty and disturbance.

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Hyungbo Shim. 2021-01-08. Disturbance Observer. https://doi.org/10.1007/978-1-4471-5102-9_100068-1

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