Universal Energy Storage and Recovery System - A Novel Approach for Hydraulic Hybrid

Abstract

The paper presents the basic principles of hybrid systems. It gives a rough approximation of factors that can affect the efficiency of a hybrid system. A Short comparison between hydraulic, mechanic and electric energy storing system is presented. In a mobile working machine, there are mainly three possible sources for energy storage or recovery which are: energy of the combustion engine, when it is working on part load, braking energy of a vehicles kinetic energy and its hydraulic system. A novel hydraulic system is introduced that is capable to store and recover energy from all energy sources of mobile working machine. The power peaks during the working cycles of the machine can be covered with energy stored in the hydraulic accumulator and so the size of the combustion engine can be reduced and dimensioned according to the average power. It also reduces the energy conversion losses. Simple and cost effective design makes it an attractive alternative for many applications.