Research on energy saving system of hydraulic excavator based on three-chamber accumulator

As the boom of a hydraulic excavator drops, the potential energy accumulated during the lifting process is converted into thermal energy and dissipated through the throttling action of the hydraulic valve, leading to excessive fuel consumption and serious energy waste. In order to address these issues, a hydraulic excavator energy saving system based on a three-chamber accumulator is proposed. Firstly, the conventional piston-type hydraulic accumulator is integrated with the hydraulic cylinder to form a three-chamber accumulator, which has a pressurizing function during energy storage. Then, a hydraulic excavator energy saving system based on three-chamber accumulator is proposed, which can store and reuse the energy loss from throttling and overflow of the hydraulic system without changing the hydraulic system of the excavator. The potential energy of the boom during drop is converted into hydraulic energy and stored in the three-chamber accumulator, which is then released to drive the boom lift, and the original system of the excavator does not work in both situations. The proposed boom speed control system ensures the operability of the excavator. The energy saving system was tested on a 21.5-ton hydraulic excavator, and the results showed that the energy consumption of the boom lifting hydraulic circuit was reduced by 47.99 %, and the engine fuel consumption was reduced by 11.42 %. This system can also be applied to other hydraulic equipment with frequent changes in potential energy of the working mechanism.