Abstract:A new hydraulic rotary brake energy recovery system was proposed, which was designed to reduce the energy loss in large hydraulic excavator's rotary system. Accumulator was used to recover braking energy in rotating brake stage, in the next stage, it driven rotary motor with variable displacement pump. The similarities and differences between the two systems hydraulic principles were described,their AMESim simulation models were established and simulation analyses were made.The simulation results show that: the new system can reduce power consumption and absorb system pressure fluctuations; turning braking energy recovery rate is 28.5%, recovery braking energy recycling rate is 76.3%, the accumulator energy recycling rate is 21.7%.So energysaving effect is evident, energyconsumption problems can be effectively improved.