Abstract
The dynamic programming equation (DPE) corresponding to nonlinear H∞ control is considered. When the cost grows quadratically in the state, it is well known that there may be an infinite number of viscosity solutions to the DPE. In fact, there may be more than one classical solution when a classical solution exists. For the case of fixed feedback control, it is shown that there exists a unique viscosity solution in the class of solutions meeting a certain growth condition, and a representation in terms of available storage is obtained. For the active control case, where the H∞ problem is represented by a differential game, a similar representation result is obtained under the assumption of existence of a suboptimal feedback control.
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This research was partially supported by AFOSR under Grant F49620-95-1-0296 and by ONR under Grant N0014-96-1-0267.
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McEneaney, W.M. A uniqueness result for the isaacs equation corresponding to nonlinear H∞ control. Math. Control Signal Systems 11, 303–334 (1998). https://doi.org/10.1007/BF02750395
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DOI: https://doi.org/10.1007/BF02750395