Robust Output Feedback Passification of Linear Systems with Unmodeled Dynamics

For the first time it is proposed and proved that some multi-input multi-output linear systems with unmodeled dynamics can be robustly rendered strictly positive real via static output feedback. In this work, various kinds of unstructured uncertainties are considered, sufficient conditions ensuring robust feedback passification are exploited, and feasible feedback gains are calculated. This new result generalizes existing ones which only deal with exactly modeled systems. It may also play an important role in output feedback variable structure control synthesis.

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