Analysis by Simulation of Different Control Algorithms of A Digital Hydraulic Two-Actuator System

Abstract

Many hydraulic systems have losses, which could be avoided with new technology. Because component efficiency can be optimized to a certain operation point, hydraulic machines are no worse than other machines. More important than the peak efficiency values of each individual component in a system is the efficiency of the whole power transfer line. In a system where the amount of required power and the velocity/force ratio are variables, components may but seldom operate at their optimal design points. A typical approach to mobile work hydraulics is to use a load-sensing pump for a hydraulic multi-actuator system. This approach is efficient but seldom, if many actuators are used simultaneously. Our recent prototype of an improved hydraulic power supply system is the Digital Hydraulic Power Management System (DHPMS), which can serve many actuators at optimised supply pressure but is also capable of motoring and transforming. This functionality holistically reduces losses in the system. Losses can be further reduced by using distributed valve systems with sophisticated control algorithms together with the DHPMS. In this study, we used digital hydraulic valves, which efficiency strongly depends on the control algorithms used. We studied here different control methods for a system with two actuators, a DHPMS, and digital valves.