Excavators generally work long hours, heavy workload, high power consumption, high calorific value of the system, and great potential energy and kinetic energy loss in the process of operation. For the boom of excavator, the potential energy recovery is of great significance to extend the life of excavator and improve the utilization rate of excavator energy. At present, the main methods proposed are: using hydraulic transformer to recover potential energy, storing energy in accumulator, or directly using accumulator to recover and store energy, and in hybrid excavator, directly coupling the boom descending potential energy recovery part to the motor for power generation and recovery, and finally storing it in battery in the form of chemical energy, The above methods are easy to realize for small hydraulic excavators, but for large hydraulic excavators, due to the heavy weight of the working device itself, large inertia, large drop potential energy, and very large flow of hydraulic cylinder, the hydraulic or electrical components used in energy recovery can not meet the requirements.
