单双泵控混合分布式挖掘机液压系统性能分析OA北大核心CSTPCD

Aiming at the problem of flow imbalance in pump-controlled asymmetric cylinders and multi-quadrant operating conditions of excavator boom,arm,and bucket cylinders,a hybrid distributed pump-controlled hydraulic system was proposed,consisting of single and double pump-controlled cylinder units.Based on the speed-load characteristics of each hydraulic cylinder of the excavator,a pump-controlled hydraulic unit using a single pump was designed for the boom with a two-quadrant condition,and two pump-controlled hydraulic units using a double pump in parallel were designed for the arm and bucket with a four-quadrant condition respectively.Taking a micro excavator as a test case,the multi-body dynamics model and hydraulic system model were established in MATLAB/Simulink.Further,PID position controllers were designed and simulation under a typical digging cycle were performed.The results show that the efficiencies of boom equipping with single pump unit and double pump in parallel unit are equivalent but the latter one can eliminate the velocity oscillation under four-quadrant conditions and under a typical digging cycle,the overall efficiency of the proposed system is 62％.