Li, XianweiYu, Changbin (Brad)Gao, Huijun2016-06-140018-9286http://hdl.handle.net/1885/102844In this paper, the problem of frequency-limited H∞ model reduction for positive linear time-invariant systems is investigated. Specifically, our goal is to find a stable positive reducedorder model for a given positive system such that theH∞ norm of the error system is bounded over a frequency interval of interest. A new condition in terms of matrix inequality is developed for characterizing the frequency-limited H∞ performance. Then an equivalent parametrization of a positive reduced-order model is derived, based on which, an iterative algorithm is constructed for optimizing the reduced-order model. The algorithm utilizes coarse reduced-order models resulting from (generalized) balanced truncation as the initial value. Both continuous- and discrete-time systems are considered in the same framework. Numerical examples clearly show the effectiveness and advantages of the proposed model reduction method. Index Terms—Frequency-limited H∞ performance, iterative algorithm, model reduction, positive systems.20152016-06-14