Characteristics of the energy regeneration and reutilization system during the acceleration stage of the swing process of a hydraulic excavator

Although the traditional energy regeneration system which uses electric or hydraulic energy recovery to regenerate part of the overflow energy loss during the acceleration and braking stages of the swing process of a hydraulic excavator, the modification cost is high and the control system is complex. To reduce the overflow energy loss of the swing process of the hydraulic excavator and to simplify the control system, a novel swing driving system based on a hydraulic accumulator to regenerate and utilize the energy automatically during the acceleration process is presented. The working mode and the assessment criteria of the swing system are analysed. The characteristics of the traditional swing system and the proposed swing system are compared. The relationships between the pressures of the two motor chambers, the pressures of the hydraulic accumulator and the motor speed of the proposed swing system in one working cycle are studied. The experimental results showed that the energy recovery efficiency of the proposed swing driving system, which can regenerate the energy automatically based on the hydraulic accumulator, was up to 80% during the acceleration stage of the swing process, and the energy consumption of the power system in one working cycle was reduced by 16.5% in comparaison with that of the traditional driving system.