A Method of Determining Optimal Parameters for the Secondary Energy Source of a Multisource Hydrostatic Drive System in Machines Working in Closed Spaces

Abstract

What benefits, from the point of view of the energy and ecological performance of a multisource drive system, can be gained for a particular control criterion through the use of appropriate secondary energy source parameters (accumulator volume Vg and initial gas pressure pg) for a given work cycle of a machine working in closed spaces? This paper describes a method of determining energy and ecological efficiency for a selected multisource drive system control criterion and presents potential benefits resulting from a proper choice of secondary energy source parameters for a selected control criterion. Using, as an example, a multisource hydrostatic drive system with a combustion engine as the primary energy source, the energy consumption and the ecological parameters (nitrogen oxides NOx emissions, carbon monoxide CO emissions and opacity DYM) were analysed for selected work cycles and different hydraulic accumulator parameters, i.e., initial gas pressure (pg) and accumulator volume (Vg). The investigations showed that the optimal parameters for the secondary energy source for energy performance criteria are different from those for the ecological criteria. It can be concluded that when a bank of accumulators is used, it will be possible to select a secondary energy source capacity that is optimal for the given work cycle, thereby improving the energy balance or the ecological balance.