非平稳工况下液压马达转速波动机制分析

针对液压马达驱动负载系统中，马达输出轴的转速波动特性直接影响负载工作稳定性和可靠性的问题，建立典型液压马达-负载系统的动力学模型，阐明液压马达等效弹簧扭转刚度的计算方法；根据非线性动力学原理，分析等效液压弹簧扭转刚度和摩擦转矩对系统转速波动特性的影响机制，提出利用高频采样计数方法对转速波动进行测试与分析。理论分析与实验结果均表明：非线性摩擦转矩、输出容积脉动、负载转矩、油液有效体积弹性模量等因素的变化影响系统的转速波动特性。

Speed Fluctuation Mechanism Analysis of Hydraulic Motor under Non-stationary Conditions

In hydraulic motor driving load system,speed fluctuation characteristics of motor shaft directly affect the stability and reliability of load.The dynamic model of typical hydraulic motor-load system was established,and the calculation method of equivalent spring torsional stiffness of hydraulic motor was expounded.According to the principle of nonlinear dynamics,the influence mechanism of torsional stiffness and friction torque on the speed fluctuation characteristics of the system was analyzed,and the high frequency sampling and counting method of the speed fluctuation measurement and analysis was put forward.The theoretical analysis and experimental results consistently indicate that the variation of nonlinear friction torque,output volume ripple,load torque and effective bulk elastic modulus of oil affect the speed fluctuation characteristics of the system.