%0 Journal Article
%T Passivity
%A Helmut Kogler
%A Markus Sch£¿berl
%A Rudolf Scheidl
%J Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering
%@ 2041-3041
%D 2019
%R 10.1177/0959651818806420
%X Digital hydraulics offers a cost-effective and robust opportunity to replace expensive and sensitive hydraulic servo valves for cylinder drives. If the digital directional valves are operated in pulse-width mode at a constant switching frequency, the mean flow rate through the valves into the actuator is controlled by the duty ratio of the pulse-width-mode signal. However, for a proper implementation of digital hydraulic linear drives, some adaptions must be made compared to common cylinder drives. In this article, a gas-loaded accumulator is used in order to tune the dynamics of the system for a smooth behavior of the drive, which is generally nonlinear. An energy-based controller according to the passivity concept in combination with a load observer is presented. Simulations show the achievable performance
%K Digital
%K hydraulics
%K switching
%K passivity
%K control
%U https://journals.sagepub.com/doi/full/10.1177/0959651818806420