双电潜泵抽油耦合模型及参数优化

为突破单电泵举升能力的上限，满足深井开采的要求，充分发挥油气井潜能，提出双电潜泵耦合举升技术，通过双电潜泵之间的协调配合，充分发挥双电潜泵的举升能力。通过对油层流入动态、井筒多相流动、举升工艺的运动学及动力学特征以及相互之间的耦合作用关系研究，建立一个双电潜泵抽油耦合数学模型，并以系统效率和产量最大为目标，利用节点分析的方法求解油井供排协调下的双电潜泵生产工作参数。在此基础上，编制了双电潜泵组合举升工艺参数设计软件，通过实例计算，对双电潜泵接力举升系统和单电泵抽油系统的电泵级数、泵功率、系统效率、最大产液量进行了对比分析。研究结果显示，双电潜泵接力举升可以降低单电泵的举升压力从而降低电泵级数和泵功率、提高系统效率；可以充分发挥两个电泵的举升能力，增加油井产量，充分发挥油井潜能，对于深井开采的双电潜泵选型设计具有重要的理论指导意义。

Research on coupled model and parameter optimization of dual-ESP pumping system

In this paper, dual-ESP coupled lifting technology was developed to break through the upper limit of single-ESP lifting capacity so as to satisfy the requirements of deep well exploitation and make full use of the potential capacity of oil and gas wells suf ficiently. By virtue of this technology, the dual-ESP lifting capacity is applied suf fi ciently based on the coordination of double electric submersible pumps. Then, a mathematical model for the coupling relationship of dual-ESP oil pumping was established after the kinematics, kinetic characteristics and coupling relationships of oil reservoir in flow performance, borehole multiphase flow and lifting technology were investigated. By means of nodal analysis method, the dual-ESP operation parameters for the supply-discharge coordination of oil wells were solved with the maximization of system efficiency and production rate as the target. And accordingly, the parameter design software for dual-ESP coupled lifting technology was prepared. And finally, a case calculation was conducted to compare the dual-ESP relay lifting system and the single-ESP pumping system from aspects of pump stage amount, pump power, system efficiency and maximum liquid production rate. It is indicated that dual-ESP lifting decreases the single-ESP lifting pressure, and consequently decreases the pump stage amount and the pump power and improve the system efficiency. And it can make full use of the lifting capacity of two electric pumps to increase the production rate of oil wells and exert the potential capacity of oil wells suf fi ciently. It is theoretically signi fi cant to the dual-ESP type selection and design for the exploitation of deep wells.