摘要
针对游梁式抽油机电动机转速存在波动、皮带传动负载扭矩波动大、皮带纵向弹性变形交变的特点,将皮带简化为无质量的具有抗拉刚度的弹簧,并综合考虑电动机转速波动、皮带与带轮之间滑动摩擦力、皮带传动瞬时负载扭矩对带轮滑动角以及等效弹簧刚度的影响,建立了游梁式抽油机皮带传动装置的动力学仿真模型。根据主从动轮瞬时转速、电动机瞬时输出扭矩的仿真结果,建立了游梁式抽油机皮带瞬时传动效率的仿真模型。仿真结果表明:1)电动机转速存在波动,皮带的纵向交变弹性变形加剧了电动机转速的高频波动;2)从动轮与主动轮之间存在转差损失,降低了皮带传动效率;3)系统达到稳定状态后,皮带传动效率呈周期性变化,皮带传动效率的变化幅度取决于负载扭矩特性。皮带平均传动效率随负载扭矩幅值的增加而降低、随扭矩平衡度的降低而降低;4)游梁式抽油机皮带的平均传动效率一般低于90%。当负载扭矩幅值较大,且扭矩平衡度较低时,皮带的平均传动效率会低于85%。
A beam pumping system is of the following characteristics： 1） the rotating speed of the motor changes instantaneously; 2） the load torque of a belt-driving unit fluctuates greatly; 3） the longitudinal elastic deformation of the belt changes instantaneously. With the belt simplified as two springs of no mass, and with the motor speed fluctuation, the sliding friction between the belt and the pulleys as well as the influences of the belt transmission＇s instantaneous load torque on the pulley sliding angle and equivalent spring stiffness taken into consideration, a dynamic simulation model of a belt driving unit of a beam pumping system is built. According to the simulation results of the driving-driven pulley＇s momentary speed and the instantaneous output torque of the motor, the simulation model of belt instantaneous transmission efficiency of beam pumping units is established. Simulation results show that： l） the motor rotating speed fluctuates periodically, and the higher frequency fluctuation of the motor rotating speed is made by the belt＇s alternating longitudinal elastic deformation; 2） there is a rotating variation loss between the driving-pulley and the driven-pulley, and the belt transmission efficiency is reduced by the driven-pulley speed loss; 3） after the system achieves a stable running state, the transmission efficiency of the belt unit changes periodically, and its varying amplitude depends on fluctuating characteristics of the load torque. Average transmission efficiency is decreasing with the load torque increasing, and it is alsodecreasing with the torque balance degree decreasing; 4） belt＇s average transmission efficiency ot a team pumping unit is usually less than 90%. When the load torque is bigger and the torque balance degree is smaller, it is possible that the average transmission efficiency of the belt driving unit is less than 85%.
出处
《工程力学》
EI
CSCD
北大核心
2013年第7期242-247,共6页
Engineering Mechanics
基金
国家自然科学基金项目(50974108
51174175)
关键词
游梁式抽油机
皮带传动
纵向弹性变形
系统动力学
传动效率
仿真模型
beam pumping unit
belt driving system
longitudinal elastic deformation
system dynamics
transmission efficiency
simulation model
