Modified model reference adaptive control for plants with unmodelled high frequency dynamics
نویسندگان
چکیده
In this paper we develop a modified MRAC strategy for use on plants with unmodelled high frequency dynamics. The MRAC strategy is made up of two parts, an adaptive control part and a fixed gain control part. The adaptive algorithm uses a combination of low and high pass filters such that the frequency range for the adaptive part of the strategy is limited. This reduces adaptation to unexpected high frequency dynamics and removes low frequency gain wind-up. In this paper we consider two examples of plants with unmodelled high frequency dynamics, both of which exhibit unstable behaviour when controlled using the standard MRAC strategy. By using the modified strategy we demonstrate that robustness is significantly improved.
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