电动叉车液压举升装置节能系统仿真研究

为了降低电动叉车液压举升装置能量消耗,采用负载敏感平衡阀驱动叉车臂实现升降功能。建立电动叉车提升装置简图,分析叉车自由提升区和第二提升区运动原理。根据能量回收方程式,推导出液压驱动数学模型和节能效率模型。在不同工况下,采用MATLAB对液压泵输出功率进行仿真。结果表明:在空载或轻载工况下,叉车臂在下降过程中,有负载敏感平衡阀比无负载敏感平衡阀的液压泵输出功率小,最大节约了69 kW;在重载工况下,叉车在上升、静止及下降过程中,有、无负载敏感平衡阀的液压泵输出功率几乎相同。合理设置负载大小,采用负载敏感平衡阀,可以实现能量回收,从而节约能量消耗。

Simulation Study on Energy Saving System of Hydraulic Lifting Device of Electric Forklift Truck

In order to reduce the energy consumption of hydraulic lifting device of electric forklift, load sensitive balance valve was used to drive lifting of forklift arm. The sketch of lifting device of electric forklift truck was established, and the motion principle of free lifting zone and second lifting zone of forklift truck was analyzed. According to the energy recovery equation, the mathematical models of hydraulic drive and energy saving efficiency were deduced. Under different working conditions, the output power of the hydraulic pump was simulated by using MATLAB. The results show that the output power of the hydraulic pump with load-sensitive balancing valve is smaller than that without load-sensitive balancing valve in the process of forklift arm descending under no-load or light-load conditions, and the output power of the hydraulic pump with load-sensitive balancing valve and without load-sensitive balancing valve is almost the same in the process of forklift lifting, resting and descending under heavy load conditions. Reasonable setting of load size and using load sensitive balance valve can realize energy recovery and consequently save energy consumption.