Digital Hydraulic Work Functions of a Prototype Wheel Loader

Abstract

This paper presents a simulation study of a prototype wheel loader with focus on work functions. The prototype machine is built for research purposes and enables research work on number of topics including digital hydraulics. The paper focuses on the control of the work functions using digital valve systems featuring equal-coded digital flow control units (DFCUs). The simulation work presented showcases energy efficiency of the digital valve control and compares selected modulation schemes for the valve system. The simulation study is based on measured load cycle data of similar type of machine. The results show that significant reduction of throttling losses is possible compared to conventional load sensing system.