In order to realize the energy recovery of the compound action of the boom and turntable of the hydraulic excavator,an energy compound recovery system of hydraulic excavator boom and turntable based on accumulatorhydraulic motor-generator was proposed.The system model was simulated and analyzed in a single working cycle under standard operating conditions.The influence of key parameters on the energy saving effect of the system was studied.The results show that under the condition of reasonable parameter matching,the energy recovery rate of the rotary brake is 61.08%,the energy recovery rate of the boom drop is 27.23%,the comprehensive energy recovery rate is 44.79%,and the comprehensive energy reuse rate reaches 47.37%,so a good energy saving effect is achieved.Within a reasonable range,the choice of a small initial volume of the accumulator and a small displacement of the recovery motor can improve the energy recovery rate of the system.