Evolutionary hardware-in-the-loop optimization of a controller for cascaded hydraulic valves

This paper presents a method for evolutionary optimization of a cascaded control structure for an industrial hydraulic valve. It proposes an iterative optimization scheme, in which the controller optimization alters between inner and outer loop parameters. The evolutionary optimization is a combination of hardware-in-the-loop evaluation of the pilot valve and a dynamic simulation of the main valve behavior. The experimental results demonstrate that the intertwined scheme results in faster convergence as it breaks down the overall optimization of the control structure into the less complex subproblems of separated optimization of inner and outer loop.