Process-Adapted Control to Maximize Dynamics of Speed- and Displacement-Variable Pumps

Within the last years, speed-variable pump drives were investigated in numerous applications. In combination with a variable displacement pump, the volume flow and the drive speed can be decoupled. In this paper the resulting degree of freedom will be used to maximize the dynamics of so called “Hydro-Gear” drive systems. By means of a novel process-adapted control concept, a dynamic model of all drive components will be transformed to a mathematical optimization problem. It will be shown that the optimum use of the two control variables depends on the actual system and process conditions. In comparison to known control strategies of speed- and displacement-variable pumps the new process-adapted approach can exemplary double the maximum volume flow gradient while reducing the necessary motor speed by over 40% at the same time.Copyright © 2014 by ASME