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CN104160155A - 检测并且打破电动潜水泵中的气锁的方法 - Google Patents

检测并且打破电动潜水泵中的气锁的方法 Download PDF

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CN104160155A
CN104160155A CN201380011908.6A CN201380011908A CN104160155A CN 104160155 A CN104160155 A CN 104160155A CN 201380011908 A CN201380011908 A CN 201380011908A CN 104160155 A CN104160155 A CN 104160155A
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pump
airlock
electric submersible
signal
detected
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CN104160155B (zh
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L·巴里奥斯
D·E·休格
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Shell Internationale Research Maatschappij BV
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D13/00—Pumping installations or systems
    • F04D13/02—Units comprising pumps and their driving means
    • F04D13/06—Units comprising pumps and their driving means the pump being electrically driven
    • F04D13/08—Units comprising pumps and their driving means the pump being electrically driven for submerged use
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D9/00—Priming; Preventing vapour lock
    • F04D9/007—Preventing loss of prime, siphon breakers
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
    • E21B43/12—Methods or apparatus for controlling the flow of the obtained fluid to or in wells
    • E21B43/121—Lifting well fluids
    • E21B43/128—Adaptation of pump systems with down-hole electric drives
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B47/00—Pumps or pumping installations specially adapted for raising fluids from great depths, e.g. well pumps
    • F04B47/06—Pumps or pumping installations specially adapted for raising fluids from great depths, e.g. well pumps having motor-pump units situated at great depth
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/06—Control using electricity
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/10—Other safety measures
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D13/00—Pumping installations or systems
    • F04D13/02—Units comprising pumps and their driving means
    • F04D13/06—Units comprising pumps and their driving means the pump being electrically driven
    • F04D13/08—Units comprising pumps and their driving means the pump being electrically driven for submerged use
    • F04D13/10—Units comprising pumps and their driving means the pump being electrically driven for submerged use adapted for use in mining bore holes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
    • F04D15/0066—Control, e.g. regulation, of pumps, pumping installations or systems by changing the speed, e.g. of the driving engine
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
    • F04D15/0088—Testing machines
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
    • F04D15/02—Stopping of pumps, or operating valves, on occurrence of unwanted conditions
    • F04D15/0209—Stopping of pumps, or operating valves, on occurrence of unwanted conditions responsive to a condition of the working fluid
    • F04D15/0218—Stopping of pumps, or operating valves, on occurrence of unwanted conditions responsive to a condition of the working fluid the condition being a liquid level or a lack of liquid supply
    • F04D15/0236—Lack of liquid level being detected by analysing the parameters of the electric drive, e.g. current or power consumption
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D31/00—Pumping liquids and elastic fluids at the same time
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D9/00—Priming; Preventing vapour lock
    • F04D9/001—Preventing vapour lock
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B2203/00—Motor parameters
    • F04B2203/02—Motor parameters of rotating electric motors
    • F04B2203/0201—Current

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Geology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • Physics & Mathematics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Control Of Non-Positive-Displacement Pumps (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Protection Of Generators And Motors (AREA)

Abstract

一种打破电动潜水泵中的气锁的方法，所述方法包括：a)监测关于泵电动机所使用的电流的测量值，所述泵电动机连接到电动潜水泵并且向电动潜水泵提供动力；b)比较测量值与阈值，以便检测气锁状况的出现；并且当检测到这些气锁条件时；c)发送超控信号，以便立即减小流到电动潜水泵的流量一预定时间段；和d)在预定时间段结束时比较关于电流的测量值与阈值，如果没有检测到气锁状况，则增大供应至电动潜水泵的动力。

Description

检测并且打破电动潜水泵中的气锁的方法
相关领域的交叉引用
本申请要求在2012年3月2日提交的美国临时专利申请No.61/605,794的权益，其全部内容在此通过引用并入本文。
技术领域
本发明涉及检测并且打破电动潜水泵中的气锁。
背景技术
在深水油气生产设施中使用电动潜水泵以提供人工升举，使得油和气可上升至水面，以进行进一步处理、存储和/或运送。在油/气混合物的操作流体性质的变化致使套管内部的液面下降并且结果在泵吸入充足的气量的情况下可能产生气锁状况，以有效闭锁泵并且防止流体通过泵流出排放管线。
针对这个问题的传统解决方案是如在US 5,015,151中所述那样，使泵停止以允许系统稳定，然后一旦系统恢复到正常状况之后通常通过使气沿着排放管线向上流动而重新启动泵。这种解决方案导致延长停机时间，增加泵启动次数，以及结果缩短了泵的使用寿命(因启动时承受的应力)。另外，如果没有检测到气锁状况，则可能损坏泵部件和/或可能使泵电动机过热。
发明内容
本发明提供了一种打破电动潜水泵中的气锁的方法，所述方法包括：a)监测关于泵电动机所使用的电流的导出值，所述泵电动机连接到泵并且为电动潜水泵提供动力；b)比较导出值与阈值，以检测气锁状况的出现；和当检测到这些气锁状况时；c)发送超控信号，以减小泵的速度一设定时间段；和d)在设定时间段结束时比较关于电流的导出值与阈值，如果没有检测到气锁状况，则增加泵的速度以恢复到正常运转状况。
附图说明
图1描绘了控制系统的一个实施例；
图2描绘了方法的一个实施例，示出了时间线上的多个步骤。
具体实施方式
气锁状况的特征在于：当气进入到泵中时，作用在泵电动机上的负荷突然下降。在气锁状况下持续运转可能损坏电动潜水泵、密封件或者电动机，并且重要的是检测气锁状况并且尽可能快地调节这些气锁状况，以便打破气锁。
若干原因中的任意一种均可引致产生气锁状况，所述若干原因包括：油/气混合物中的气体体积部分增加；泵在过高的流速下操作，使得液面下降到泵吸入口以下；和因热油减少、气/水段塞等造成的快速流体性质变化。
检测并且打破气锁状况的方法包括：监测泵的操作且比较操作和表示气锁状况的一个或多个预定界限值或者警报的初始步骤。可以监测多个变量，并且可以在水面、海底或者井眼中实施测量。优选的测量是电动潜水泵电动机安培数的运行标准偏差。
预定界限值或者警报可以是基于系统设计而设定的硬界限值，或者其可以是基于系统的正常运行或者以往运行的偏差的运行标准偏差的一个示例。
存在多种方式来发送超控信号，以便一旦达到气锁状况便减小泵的速度。如图2所示，可以将通常为最大频率的超控信号减小至预定最小频率值。当致动时，超控可以立即减小至对应于电动潜水泵的电流频率的值。此后，超控可以逐渐缓降至其最小值，以便防止作用在泵上的负荷过快变化。使用低信号选择器将用于减小传递到泵电动机的信号，以便减小流过泵的流量。如上所述，如果没有尽快地采取行动，则可能损坏泵，因此应当在遭遇气锁状况之后快速实施发送超控信号的步骤。
一旦减小流量，则设定定时器，以保持低流量一设定时间段。基于系统的设计和油井的特征可构造并且可设定这种时间量。另外，可以存在这种定时器的手动超控，以使得操作者可决定绕过该设定时间段并且尝试在时间段结束之前增大流速。
在时间段结束时或者在操作者人工干预时，再次测量适当的变量并且与警报界限值进行比较，以便确保在系统中不再存在气锁状况。如果泵仍然处于气锁状态中，则保持泵处于低流量的状况下另一设定时间段。如果泵不再处于气锁状态中，则将增大泵流速。这可以通过增大从压力控制器传递至泵的信号的频率并且将超控信号重置至最大频率信号来实现。
可以以设定的缓变率增加流速，以防止系统斜升太快并且返回到气锁状况。缓变率是预定比率，但是其可由操作者构造或者设定。
将参照图1和图2来进一步描述本发明。图1示出了标准压力控制器10，所述标准压力控制器10用于在正常条件期间控制泵操作。超控信号50在正常操作期间保持处于操作频率条件下，但是当遭遇气锁状况时超控信号50减小至最小频率。在被传递至频率斜升限制控制器30之前，超控信号和来自压力控制器的信号通过低信号选择器20。来自控制器30的信号被传递到电动机控制器40，所述电动机控制器40控制驱动电动潜水泵的电动机。在某些实施例中，在系统中包括抗积分饱和信号60，以便当控制系统从超控信号切换至压力控制时防止冲击。
图2示出了本发明的方法的操作。在正常操作期间，超控信号保持处于操作频率。当检测到气锁状况时，信号减小至最小频率信号，以便提供通过泵的最小流量。在定时器持续时间(或者在采取人工干预的情况下更早)之后，重置超控并且将超控缓慢增加到最大频率。在此时，压力控制器控制泵，这是因为两个信号通过低信号选择器并且持续正常、稳定的操作，除非再次遭遇气锁状态。
本发明使得控制器能够在不需要重复关闭电动潜水泵的条件下处理气锁状况和打破气锁，重复关闭电动潜水泵因增加泵的启动次数而可能导致缩短泵的使用寿命。

Claims (8)

1.一种用于打破电动潜水泵中的气锁的方法，所述方法包括：
a.监测关于泵电动机所使用的电流的导出值，所述泵电动机连接到所述电动潜水泵并且向所述电动潜水泵提供动力；
b.比较所述导出值与阈值，以便检测所述气锁状况的出现；并且当检测到这些气锁条件时；
c.发送超控信号，以便立即减小流到所述电动潜水泵的流量达一预定时间段；和
d.在所述预定时间段结束时比较关于所述电流的导出值与所述阈值，如果没有检测到所述气锁状况，则增大供应到电动潜水泵的动力。
2.根据权利要求1所述的方法，其中，所述导出值是所述泵电动机安培数的运行标准偏差。
3.根据权利要求1所述的方法，其中，所述超控信号是通常处于最大频率条件下、但是当检测到所述气锁状况时将所述信号改变至预定最小频率的信号。
4.根据权利要求3所述的方法，其中，通过低信号选择器管理超控信号和压力控制信号。
5.根据权利要求1所述的方法，其中，操作者能够在发出所述超控信号之后的任意时间越过所述预定时间段并且强制进行步骤d)的比较。
6.根据权利要求1所述的方法，其中，根据规定的缓变率来增加供应到所述电动潜水泵的动力。
7.根据权利要求1所述的方法，还包括：在步骤d)期间，如果检测到所述气锁状况，则持续发送超控信号达第二预定时间段，然后在所述第二预定时间段结束时，比较关于所述电流的导出值与阈值，而如果没有检测到气锁状况，则增加供应到电动潜水泵的动力。
8.根据权利要求8所述的方法，还包括：持续发送超控信号达一后续预定时间段，直到没有检测到气锁状况为止。
CN201380011908.6A 2012-03-02 2013-02-27 检测并且打破电动潜水泵中的气锁的方法 Expired - Fee Related CN104160155B (zh)

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US201261605794P 2012-03-02 2012-03-02
US61/605,794 2012-03-02
PCT/US2013/027926 WO2013130536A1 (en) 2012-03-02 2013-02-27 Method of detecting and breaking gas locks in an electric submersible pump

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NO339736B1 (en) * 2015-07-10 2017-01-30 Aker Subsea As Subsea pump and system and methods for control
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GB201413388D0 (en) 2014-09-10
AU2013226214B2 (en) 2016-03-10
WO2013130536A1 (en) 2013-09-06
MY183956A (en) 2021-03-17
NO20141075A1 (no) 2014-09-05
CN104160155B (zh) 2017-06-06
US20150056082A1 (en) 2015-02-26
GB2513062A (en) 2014-10-15

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