Abstract:  Aiming at the problem of low power utilization rate of excavator hydraulic system, in the process of 21 t-class excavator excavation and loading operation, the data analysis and efficiency improvement before and after the improvement of the hydraulic system of the working device was studied. Firstly, the data acquisition system was built, and the power and utilization analysis method of hydraulic system was established. Then, based on the analysis of power utilization in MATLAB software and the statistics of power consumption for 100 complete operation cycles, the regenerative energy utilization and flow distribution were studied on the basis of improving the hydraulic system and control strategy of the working device. Finally, the improved excavation loading test was carried out and the degree of efficiency improvement of hydraulic system was analyzed. The research results show that although the output energy of the main pump was reduced, the energy used by the hydraulic cylinder of boom and stick was improved, the utilization rate of the hydraulic system during the cycle operation of the excavator can be increased by 5.5%. By adding the boom down regeneration function, stick out regeneration function, and the flow limiting function of the large chamber of the bucket, the power utilization rate of the hydraulic system and the movement coordination of the working device were improved.
Key words:  excavator; hydraulic system; control strategy ;efficiency analysis; experimental comparison

LIU Zhi-dong, LI Ying-ying, WANG Qing-yun, et al. Efficiency analysis and testing of hydraulic system of excavator［J］.Journal of Mechanical & Electrical Engineering, 2021,38(12):1617-1621,1627.