A large amount of gravitational potential energy will be wasted when the boom drops frequently in hydraulic excavator working process.Therefore,boom potential energy regeneration can effectively improve the energy efficiency of the excavator.Based on the experimental platform of 1.7×104 N hydraulic excavator,a combined energy-saving boom structure and its hydraulic regeneration circuit were designed,the boom dynamics model,hydraulic model and controller model were established to carry out multi-simulation model co-simulation,and a control strategy was proposed for the boom potential energy regeneration based on fuzzy PID control strategy.The results show that the energy saving efficiency of the boom potential energy regeneration system controlled by fuzzy PID is 25.57%,which is higher than the 18.04% of the traditional PID control strategy,compared with the traditional PID controlled no-accumulator model.