Ball, Helton, and Walker (BHW) derived the nonlinear dissipative controller formulas with the assumption implying that no stable mode uncontrollable from the exogenous input. The assumption is more restrictive than that considered in DGKF. In this paper, we address the numerical difficulty encountered by BHW’s controller formulas when the assumption is not satisfied. Next, we propose a modified nonlinear dissipative controller and successfully remove the numerical difficulty. We also show that the linear version of the proposed controller formulas is identical to the DGKF $H∞$ controller. An example is given to demonstrate constructing the proposed controller and simulating the closed-loop pulse responses.

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