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AbstractWe present a recurrent neural-network (RNN) controller designed to solve the tracking problem for control systems. We demonstrate that a major difficulty in training any RNN is the problem of exploding gradients, and we propose a solution to this in the case of tracking problems, by introducing a stabilization matrix and by using carefully constrained context units. This solution allows us to achieve consistently lower training errors, and hence allows us to more easily introduce adaptive capabilities. The resulting RNN is one that has been trained off-line to be rapidly adaptive to changing plant conditions and changing tracking targets.The case study we use is a renewable-energy generator application; that of producing an efficient controller for a three-phase grid-connected converter. The controller we produce can cope with random variation of system parameters and fluctuating grid voltages. It produces tracking control with almost instantaneous response to changing reference states, and virtually zero oscil-$ This work was supported in part by the U.S. National Science Foundation under Grant EECS 1059265/1102159, the Mary K. Finley Missouri Endowment, and the Missouri S&T Intelligent Systems Center.Email addresses: michael.fairbank@virgin.net (Michael Fairbank), sli@eng.ua.edu (Shuhui Li), xfu@crimson.ua.edu (Xingang Fu), E.Alonso@city.ac.uk (Eduardo Alonso), dwunsch@mst.edu (Donald Wunsch) Preprint submitted to Neural Networks September 23, 2013 lation. This compares very favorably to the classical proportional integrator (PI) controllers, which we show produce a much slower response and settling time. In addition, the RNN we propose exhibits better learning stability and convergence properties, and can exhibit faster adaptation, than is achievable with adaptive critic designs.