Abstract: The load characteristic of pumping units is a cyclicity loading. In order to startup and run the pumping units normally, the electrical motor theory installed power of pumping unit was usually higher than running power for requirement of the motor margin, which makes the electric power lost. The reasonable upper limit of electrical motor power utilization ratio by theorical check of the motor heating conditions、overload capacity and startup character and the lower limit by characteristic curve of electrical motor were made. It had been checked by experimental study. Declining electrical motor of pumping units installed power reasonably not only can raise electrical motor power utilization ratio and decrease initial investment, but also can make importance for energy saving of oilfield. 

Key words: Pumping unit, Electrical motor, Power utilization ratio, Power, Torque, Efficiency

摘要： 游梁式抽油机的负载属于一种周期性交变载荷，为了满足抽油机正常启动、运行，所用电动机装机功率普遍高于理论装机功率，使电动机长期处于低负荷运行，造成能耗浪费。通过对电动机发热条件、过载能力及启动性能的理论校验与分析，确定了电动机负载率的合理上限，根据电动机工作特性曲线确定了负载率的合理下限，并利用试验研究进行了验证，合理地降低抽油机所用电动机的装机功率，不仅可以提高油井电动机负载率，降低初期投入，而且对油田生产节能降耗意义重大。

关键词: 抽油机 , 电动机 , 负载率 , 功率 , 扭矩 , 效率