AUTHOR=Li Jiansong , Li Shaohui , Ji Zhi , Wang Yunfei TITLE=Design and energy analysis of a flywheel-based boom energy regeneration system for hydraulic excavators JOURNAL=Frontiers in Energy Research VOLUME=Volume 11 - 2023 YEAR=2023 URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2023.1202914 DOI=10.3389/fenrg.2023.1202914 ISSN=2296-598X ABSTRACT=The global energy crisis and growing environmental concerns provide a strong impetus for the development of fuel-efficient hydraulic excavators (HEs). The boom potential energy of a conventional HE is consumed by throttling in a lowering process, which is a major reason for energy inefficiency. To solve the issue, this paper presents a flywheel-based boom energy regeneration system for HEs using load sensing systems. The otherwise wasted boom potential energy is regenerated by a pump/motor and stored in a flywheel. The recaptured energy is reused in a form of pressure energy released to the pump outlet. The energy efficiencies of a conventional load sensing system and the proposed system are analysed. A control strategy is proposed to optimize the energy-saving procedure. To obtain a more reliable simulation model, the coasting experiment of the flywheel is carried out to obtain the key parameters related to the friction of the flywheel. A 4-t HE is used as a study case to investigate the energy-saving potential of the proposed system. Numeric simulations show that the energy-saving rate, compared with a conventional load-sensing system, is about 32.7% in a typical digging and dumping cycle. This research indicates the flywheel-based scheme is promising for developing energy-efficient HEs.