Performance analysis of hydraulic excavator powertrain hybridization

Traditional methods have played an important role in energy saving of hydraulic excavators. However the excavators are still working with low fuel efficiency and bad exhaust. So, new technologies are urgently needed to further reduce fuel consumption and pollutant emissions. Researchers have begun to focus on hybrid technology of hydraulic excavators. This paper systematically analyzed the performance of the powertrain hybridization of hydraulic excavator and compared the main performance among the parallel, the series and the conventional configurations based on a 5-ton excavator. The data of the conventional excavator used for analysis were gathered from the real working process, while that of the hybrid configurations were got from the model simulation. The data used as the load input of the model were also gathered from the real working process. The model of the hybrid powertrains were built with the reliable lookup-table approach, which provides deep insight into the energy conversion phenomena. The presented results indicate that the parallel hybrid powertrain features better fuel economy than the other two configurations in heavy mode and light mode, whereas both the series and parallel hybrid powertrains feature better fuel economy in medium mode. Considering the performance and cost synthetically, the parallel powertrain is the best configuration for hybrid excavators at present. (C) 2008 Elsevier B.V. All rights reserved.