Simulation-based optimization of a sliding mode controller for directional valves

This contribution discusses the topic of sliding mode control of a directional control valve. Based on the motivation to reduce the complexity of existing control laws and hence, to accelerate the parametrization process of such controllers, an approach based on the second order sliding mode control is presented. Typically in the context of hydraulic systems, evolutionary optimization is used as a parametrization method for such controllers. However, the hardware-based optimization is a long-lasting process, that requires several thousand of experiments. To accelerate the design process, this contribution utilizes a model-aided process. For the hydraulic valve, a physically inspired model is presented and the parametrization of the control law is carried out in simulation. The comparison of real and simulated step responses as well as frequency measurements show a high similarity, such that there is no loss of control accuracy using a simulation-based optimization process for designing a sliding mode controller for a hydraulic valve.