CN1117915C - Method and device for controlling high-pressure water injecting pump station - Google Patents
Method and device for controlling high-pressure water injecting pump station Download PDFInfo
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- CN1117915C CN1117915C CN00105544A CN00105544A CN1117915C CN 1117915 C CN1117915 C CN 1117915C CN 00105544 A CN00105544 A CN 00105544A CN 00105544 A CN00105544 A CN 00105544A CN 1117915 C CN1117915 C CN 1117915C
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Abstract
The present invention relates to the automatic control of a high-pressure large-power water injecting centrifugal pump group for oil exploitation. The dry pressure difference of a pump outlet is compared with a set pressure difference, and an electric valve at the pump outlet is controlled by a frequency converter to smoothly, continuously and synchronously adjust the opening degree of each valve so as to realize closed loop automatic control. A dry pressure difference sensor arranged at the pump outlet sends signals to a process parameter controller 6 of which the output end is connected with a programmable controller; the output end of the process parameter controller 6 and the output end of the programmable controller 2 are connected with the frequency converter 7; the output end of the frequency converter 7 is connected with the electric valve 4 at the pump outlet. The present invention has the advantages of stable water injection, high-efficiency running, closed loop monitoring, reliability and accuracy increase, low cost and convenient construction; particularly, the present invention does not need to replace a pump valve and an original arrangement in realizing the existing pump station.
Description
Technical field
To the duty automation control and the monitoring technology of water injection technology and high-tension high-power centrifugal pump group, be a kind of controlling high-pressure water injecting pump station method and device thereof when the present invention relates to the oil water flooding recovery.
Background technology
The middle and later periods oil reservoirs pressure that the oil field produces descends, and needs water filling to strengthen strata pressure and recovers the oil.Some water flooding pump stations are controlled water injection rate by manual adjustment pump valve door now, can not reach the requirement of steady water filling, and rate descended when water filling was produced, waste electric energy and water source, and pump also only is provided with general safeguard protection, poor reliability.Adopt high-power variable-frequency control technique control of pump motor partly to address this problem, but large-size variable-frequency equipment depends on import, costs an arm and a leg, input-output ratio is uneconomical, and cost is difficult to reclaim, and uses at the high-tension high-power pumping plant to have difficulty.
At present, the method of another solution is under the prerequisite of not changing former pump equipment, adopt the aperture of auto-control pump discharge valve to make pump controlledly export water injection pressure and water injection rate, make water injecting pump can be implemented in operation continuously in the efficient district scope, reach saves energy and water source, slow down the pump valve wearing and tearing, rate and automatization level when improving water filling.This method is mainly according to the parallel operation characteristic (Q-H) of centrifugal pump, to the electric current (I) of the discharge capacity (Q) in pump (motor) work, pressure (P), motor respectively pickoff signals carry out the A/D conversion, indirectly pump discharge, dry-pressing parameters such as electric current poor, motor are calculated by Industrial Personal Computer (IPC), the output control signal, regulate water injection rate through the electronic stepping ratio adjusting valve change aperture of D/A conversion and control pump discharge again, reach the control purpose.There is following problem in this method: the one, and the pump discharge valve opening is regulated in stepping can not be smoothly continuous, be difficult to reach the steady flood effectiveness of closed loop, simultaneously owing to need carry out A/D and D/A conversion, the hardware circuit complexity, reduced reliability, need carry out loaded down with trivial details statistics on the software, relatively wait mathematical computations, the injection flow pressure tracking is delayed, the regulation and control error is bigger, is difficult to produce a desired effect; The 2nd, when transforming, need change water-injection station ratio stepping motor operated valve, increased investment, the rebuilding construction cycle is long, is unfavorable for promoting; The 3rd, still be to adopt thermoelectric corner electrical bridge principle to monitoring and protectings such as temperature; the temperature signal that detects is sent into converter unit and is amplified and be converted to a milliampere current signal, delivers to PLC again and carries out temperature conversion, and temperature error is big; circuit reliability is poor, is difficult to reach the trouble-free purpose of long-time running.
Summary of the invention
The object of the invention provides a kind of by flow, the dry-pressing of pump output being looked into the level and smooth synchronously adjusting continuously of monitoring calculation control pump outlet valve aperture poor, the pump motor electric current, realize the steady water filling of pump closed loop, make pump be in the operation of efficient district all the time, reach steady water filling, saves energy and water source, improve rate when producing, original water flooding pump station transformation be need not to change or change pump valve and original layout, reduce the controlling high-pressure water injecting pump station method and the device thereof of cost, easy construction.
The present invention realizes by following technical method:
Parallel operation characteristic (Q-H) according to centrifugal pump, aperture by the control pump outlet valve is regulated water filling, indirectly the parameters such as electric current of pump discharge, dry-pressing difference and pump motor are controlled, make pump keep efficient operation, the dry-pressing of setting pump discharge as required is poor, during work the dry-pressing of continuous acquisition pump discharge poor, with the dry-pressing difference of setting pump discharge relatively, control pump outlet electrically operated valve is adjusted the switching and the aperture of valve smoothly, continuously, synchronously, makes water filling steady.
The present invention also realizes by following technical method:
Adopt the motor of Frequency Converter Control pump discharge electrically operated valve.
When water injection rate satisfies the dry-pressing difference, according to the relation between the characteristic (H-Q) of employed pump lift, shaft power (Pn), the pump efficiency (η), adjust the aperture of pump discharge valve, improve the automatic control accuracy of closed loop, pump is moved under rated discharge and rated head keep maximum pump efficiency.
Safe operation is monitored automatically and is protected to pumping plant when controlling water filling automatically; water injection pressure, flow, pump efficiency and each pump motor front and back bearing bush temperature, circulating water pressure, lubricating oil pressure are set; the multinomial measuring control point of the liquid level of water tank; signal is handled by programmable logic controller and industrial computer; and can manually revise, its temperature signal is directly discerned by the computer program address lookup.
Description of drawings
Description of drawings of the present invention is as follows
Fig. 1 is a controlling high-pressure water injecting pump station method logic software block diagram;
Fig. 2 is a controlling high-pressure water injecting pump station method water filling decision logic software block diagram;
Fig. 3 efficiently distinguishes operation curve figure for the controlling high-pressure water injecting pump station method;
Fig. 4 is a controlling high-pressure water injecting pump station device schematic diagram.
The specific embodiment
Details are as follows in conjunction with the accompanying drawings for technical method of the present invention:
Characteristic (Q-H) according to the parallel operation of pumping plant centrifugal pump, aperture by the control pump outlet valve is regulated water filling, indirectly to pump discharge, dry-pressing is poor, parameters such as the electric current of pump motor are controlled, make the pump work state meet the parameter of setting, keep efficient operation, the present invention is poor in pump delivery outlet continuous acquisition outlet dry-pressing, compare with the water filling dry-pressing difference of setting according to water injection well, the dry-pressing excursion requires to remain on+/-0.2MPa, thereby by level and smooth switching and the aperture of adjusting valve continuously of Frequency Converter Control pump discharge electrically operated valve motor, in adjustment process, require the pump motor electric current less than or keep rated value, when dry-pressing was annotated pressure less than setting, the pump discharge valve increased aperture; When dry-pressing greater than when setting value, reduce the aperture of each pump discharge valve; When dry-pressing equals to set value, keep former valve opening, control automatically thereby implement closed loop, reach the purpose at steady water filling, saves energy water source.
The present invention guarantees that according to the characteristic curve (Q-H) of pump itself pump moves the maximum pump efficiency of maintenance under rated discharge and rated head, when water injection rate satisfies dry-pressing pressure, according to the aperture that concerns assistant regulating and controlling pump discharge valve between pump lift characteristic (H-Q), shaft power (Pn), the pump efficiency (η), improve the automatic control accuracy of closed loop, make pump can be implemented in operation continuously in the efficient district scope.The efficient of pump is influenced to the restriction loss of each regional water filling office valve group and water injection well quantity, in-place permeability by the water flooding pump station outlet valve, in a certain section time zone, objectively satisfying injection flow Q and dry-pressing H curve, be the adjustable district of each pump electrically operated valve, the requirement of water injection pressure is not only satisfied in this zone, and influence is less relatively to pump efficiency simultaneously.Want pump to remain on the operation of efficient district relatively, when water injection rate satisfies the dry-pressing curve, also to consider the aperture that concerns many pump discharge high-tension electricities of synchronization modulation valve between pump lift characteristic (H-Q), shaft power (Pn) and the pump efficiency (η), condition is: 1. dry-pressing difference should less than+/-0.2MPa, make pump dry-pressing difference little, to satisfy the requirement of lift as far as possible; 2. shaft power Pn＜1.732 * electric moter voltage * current of electric * η electric efficiency; 3. require each pump type identical characteristics curve basic identical.
Draw each pump (Q-H) characteristic, pump efficiency (η) according to pump self character curve and the theoretical empirical Calculation formula of known conditions, shaft power curve, when each pump efficiency in service departs from efficient district scope, the switching degree of each pump discharge valve of stepless adjusted in concert, make pump remain on the operation of efficient district relatively, general pump η is 75%～90%.
Safe operation is monitored automatically and is protected to pumping plant when controlling water filling automatically; multinomial measuring control point is set; signal is handled by programmable logic controller and industrial computer, and can manually revise, and its temperature signal is directly discerned by the computer program address lookup.Measuring control point and parameter thereof can comprise:
1. each water injecting pump import low pressure 0.05MPa sound and light alarm.
2. 70 ℃ of warnings of the forward and backward bush high-temperature of each water injecting pump.
3. 70 ℃ of warnings of the forward and backward bush high-temperature of each water filling motor.
4. 110 ℃ of warnings of each water filling motor stator temperature.
5. grease pump exports header high pressure 0.3MPa, low pressure 0.1MPa; When being low to moderate 0.08Mpa again, low pressure starts emergency bearing oil pump.
6. establishing low pressure 0.07MPa on each machine, the pump place lubricating oil pipe line reports to the police.
7. cooling water pipeline is established low pressure 0.15MPa warning in the water filling pump house.
8. two 3000m3 water tank liquid level continuous detecting are established a high position, low alarm.
9. circulating water pool is established low alarm.
10. water injecting pump import low-temperature measurement.
11. establish the dry-pressing control point in the high pressure valve group, the requirement of dry-pressing excursion+/-0.2MPa, by the adjusting of motor operated valve in the water filling pump house, make the kinematic parameter of water injecting pump be in the operation of efficient district all the time, in adjustment process, require electric current less than the motor rated current.
The present invention controls water filling automatically and pumping plant safety is monitored automatically and the method for protection can specifically be implemented by regulate and control method logic software block diagram and the water filling decision logic software block diagram of Fig. 1 and Fig. 2.
The controlling high-pressure water injecting pump station device that the present invention designs and produces according to said method, comprise and be arranged on header, each water injecting pump inlet, grease pump outlet header, gather the sensor of pressure and flow on the water injecting pump cooling water pipeline, be arranged on each pump motor and gather electric current, the sensor of voltage signal, be arranged on the collection liquid level signal sensor on water tank and the circulating water pool, the control pump outlet electrically operated valve 4 regulation and control water fillings that are connected with programmable logic controller 2 or computer 3 of above-mentioned each sensor groups 1, the sensor 5 of measuring the dry-pressing difference is housed at pump discharge, sensor 5 is delivered to procedure parameter controller 6 with signal, procedure parameter controller 6 outputs are connected with computer 3 with programmable logic controller 2, the output of procedure parameter controller 6 and programmable logic controller output 2 also connect and control frequency converter 7, and frequency converter 7 outputs are connected with pump discharge electrically operated valve 4.
Controlling high-pressure water injecting pump station device of the present invention also comprises: at the forward and backward bearing shell of water injecting pump motor, temperature pick up 8 is equipped with at the motor stator place, and each temperature pick up 8 directly is connected with computer 3, and signal is directly handled by computer 3.Programmable logic controller 2 and computer 3 are connected with protection alarm 10 with water injecting pump motor 9 respectively, control it and close down and report to the police.The sensor 5 of the dry-pressing difference of installing at pump discharge is the high-precision pressure sensor of 20Mpa/4-20mA, will measure the dry-pressing physical parameter and be converted to the 4-20mA signal of telecommunication and send into procedure parameter controller 6.Frequency converter 7 can be controlled pump discharge electrically operated valve 4 synchronous operations more than.
Below in conjunction with accompanying drawing in detail the present invention is described in detail: the controlling high-pressure water injecting pump station device that designs and produces according to said method, comprise and be arranged on header, each water injecting pump inlet, grease pump outlet header, the water injecting pump cooling water pipeline is gathered pressure and flow transmitter, be arranged on each pump motor and gather electric current, the sensor of voltage signal, be arranged on the collection liquid level signal sensor on water tank and the circulating water pool, the control pump outlet electrically operated valve 4 regulation and control water fillings that are connected with programmable logic controller 2 or computer 3 of above-mentioned each sensor groups 1, the 20Mpa/4-20mA high accuracy dry-pressing differential pressure sensor 5 of measuring the dry-pressing difference is housed at pump discharge, to measure the dry-pressing physical parameter is converted to the 4-20mA signal of telecommunication and sends into procedure parameter controller 6, procedure parameter controller 6 outputs one tunnel connect frequency converter 7 control pumps outlet electrically operated valve 4 stepless speed regulation switching degree, one tunnel output increases, subtract water filling switching value signal and give programmable logic controller 2, the phase place that is changed the output AC electricity of frequency converter 7 by programmable logic controller 2 output forward or reverse signals changes pump discharge electrically operated valve 4 slow opening or Slow Close, also have one tunnel output to be connected communication with computer 3, imitate correction value by computer 3 output water pumps and come automatically or the manual correction pump efficiency, make water pump 9 remain on the operation of efficient district.Above-mentioned frequency converter 7 can be controlled many pump discharge electrically operated valve 4 synchronous operations.
Controlling high-pressure water injecting pump station device of the present invention also comprises: at the forward and backward bearing shell of water injecting pump motor, temperature pick up 8 is equipped with at the motor stator place, and each temperature pick up 8 directly is connected with computer 3, and signal is directly by Computer Processing.Programmable logic controller 2 is connected with protection alarm 10 with water injecting pump motor 9 respectively with computer 3; computer 3 is handled the operating condition that each water injecting pump and whole system are adjusted in monitoring; controlling it closes down and reports to the police; computer 3 also carries out the many picture monitoring of closed loop to whole system; the equipment dynamic duty situation of pumping plant comes into plain view, and need not manual intervention.
The critical piece that apparatus of the present invention are selected for use is as follows: frequency converter FRN5P9S (Japan), programmable logic controller S7-300 (Siemens), expansion module able to programme (Siemens), dry-pressing sensor GF-50/20Mpa (sino-america joint-venture), pressure sensor TKG-E-1 (Italy), temperature pick up DS1820 type (U.S.), liquid level sensor KYCW07 type (U.S. NOVA), procedure parameter controller KEX-D type (Japanese RKC), control cables (homemade).
The present invention has following function:
(1) pumping station operation breaks down and exceeds setting value and in time reports to the police automatically and point out protection;
(2) auto-control water filling;
(3) microcomputer shows each merit kinematic parameter, capital equipment operation conditions;
(4) automatic printing reports and require every accumulative total of parameter.
Advantage of the present invention is to make the level and smooth continuously adjusting of pump discharge valve opening, makes the steady water filling of pump closed loop, begins Be in eventually the operation of efficient district, saved the energy, improved production time efficiency, it is many to carry out closed loop to pumping plant Picture monitoring, is transmitted, is gone out table and automatically carry out at data acquisition, save artificial, to water storage number, liquid level, But the temperature comprehensive monitoring of the pressure of each pump inlet pressure, lubricating system, cooling system has improved reliable The property and accuracy, can realize that particularly original water flooding pump station transformation need not to change or change pump valve and original cloth Office, low, the easy construction of cost.
Claims (9)
1. controlling high-pressure water injecting pump station method that is used for oil exploitation, parallel operation characteristic (Q-H) according to centrifugal pump, aperture by the control pump outlet valve is regulated water filling, indirectly the current parameters of pump discharge, dry-pressing difference and pump motor is controlled, make pump keep efficient operation, it is characterized in that: the dry-pressing of setting pump discharge as required is poor, the dry-pressing of continuous acquisition pump discharge is poor during work, compare with the dry-pressing difference of setting pump discharge, control pump outlet electrically operated valve is adjusted the switching and the aperture of valve smoothly, continuously, synchronously, makes water filling steady.
2. controlling high-pressure water injecting pump station method according to claim 1 is characterized in that: by the motor of Frequency Converter Control pump discharge electrically operated valve.
3. controlling high-pressure water injecting pump station method according to claim 1, it is characterized in that: when water injection rate satisfies the dry-pressing difference, according to the relation between the characteristic (H-Q) of employed pump lift, shaft power (Pn), the pump efficiency (η), adjust the aperture of pump discharge valve, improve the automatic control accuracy of closed loop, pump is moved under rated discharge and rated head keep maximum pump efficiency.
4. controlling high-pressure water injecting pump station method according to claim 1; it is characterized in that: safe operation is monitored automatically and is protected to pumping plant when controlling water filling automatically; water injection pressure, flow, pump efficiency and each pump motor front and back bearing bush temperature, circulating water pressure, lubricating oil pressure are set; the multinomial measuring control point of the liquid level of water tank; signal is handled by programmable logic controller and industrial computer; and can manually revise, temperature signal is directly discerned by the computer program address lookup.
5. regulation device that is used for the high-pressure water injecting pump station of oil exploitation, comprise and be arranged on header, each water injecting pump inlet, grease pump outlet header, gather the sensor of pressure and flow on the water injecting pump cooling water pipeline, be arranged on each pump motor and gather electric current, the sensor of voltage signal, be arranged on the collection liquid level signal sensor on water tank and the circulating water pool, above-mentioned each sensor groups (1) links to each other with programmable logic controller (2) or computer (3) and fetches control pump outlet electrically operated valve (4) group regulation and control water filling, it is characterized in that: the sensor (5) of measuring the dry-pressing difference is housed at pump discharge, sensor (5) is delivered to procedure parameter controller (6) with signal, procedure parameter controller (6) output is connected with computer (3) with programmable logic controller (2), the output of procedure parameter controller (6) and programmable logic controller (2) output also connect and control frequency converter (7), and frequency converter (7) output is connected with pump discharge electrically operated valve (4).
6. controlling high-pressure water injecting pump station device according to claim 5, it is characterized in that: at the forward and backward bearing shell of water injecting pump motor, temperature pick up (8) is equipped with at the motor stator place, and each temperature pick up (8) directly is connected with computer (3), and signal is directly handled by computer (3).
7. controlling high-pressure water injecting pump station device according to claim 5 is characterized in that: programmable logic controller (2) and computer (3) are connected with protection alarm (10) with the water injecting pump motor respectively, control it and close down and report to the police.
8. controlling high-pressure water injecting pump station device according to claim 5, it is characterized in that: the sensor (5) of the dry-pressing difference of installing at pump discharge is the high-precision pressure sensor of 20Mpa/4-20mA, will measure the dry-pressing physical parameter and be converted to the 4-20mA signal of telecommunication and send into procedure parameter controller (6).
9. controlling high-pressure water injecting pump station device according to claim 5 is characterized in that: frequency converter (7) is the pump discharge electrically operated valve (4) of Synchronization Control more than one simultaneously.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN00105544A CN1117915C (en) | 2000-03-31 | 2000-03-31 | Method and device for controlling high-pressure water injecting pump station |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN00105544A CN1117915C (en) | 2000-03-31 | 2000-03-31 | Method and device for controlling high-pressure water injecting pump station |
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| Publication Number | Publication Date |
|---|---|
| CN1315613A CN1315613A (en) | 2001-10-03 |
| CN1117915C true CN1117915C (en) | 2003-08-13 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN00105544A Expired - Fee Related CN1117915C (en) | 2000-03-31 | 2000-03-31 | Method and device for controlling high-pressure water injecting pump station |
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Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102278100B (en) * | 2011-06-01 | 2014-07-02 | 中国石油天然气股份有限公司 | Constant-current control device and method for high-pressure water injection well |
| CN105134576B (en) * | 2015-09-29 | 2018-03-16 | 上海市城市排水有限公司 | A kind of drainage pumping plant water pump operation performance diagnogtics method and diagnostic device |
| CN107366625B (en) * | 2017-06-27 | 2019-01-29 | 江苏京川水设备有限公司 | A kind of drainage pumping plant automatic control system and its design method |
| CN109812710B (en) * | 2019-01-28 | 2020-10-27 | 新昌县陆恒机械有限公司 | Oil field pipeline supercharging device |
| CN110331967A (en) * | 2019-06-11 | 2019-10-15 | 中国石油天然气股份有限公司 | Control and protection system and method for on-load starting of high-pressure water injection pump |
| CN110593828B (en) * | 2019-06-24 | 2023-12-22 | 中国石油天然气股份有限公司 | Fluid pressure wave code experimental device and method |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5042584A (en) * | 1990-12-05 | 1991-08-27 | Mcmurray Oil Tools, Inc. | Stacked water regulator and method of use |
| US5979558A (en) * | 1997-07-21 | 1999-11-09 | Bouldin; Brett Wayne | Variable choke for use in a subterranean well |
| CN2358225Y (en) * | 1998-04-03 | 2000-01-12 | 杨睿 | Practical wireless cycle monitoring system for working condition of oil-producing machine |
-
2000
- 2000-03-31 CN CN00105544A patent/CN1117915C/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5042584A (en) * | 1990-12-05 | 1991-08-27 | Mcmurray Oil Tools, Inc. | Stacked water regulator and method of use |
| US5979558A (en) * | 1997-07-21 | 1999-11-09 | Bouldin; Brett Wayne | Variable choke for use in a subterranean well |
| CN2358225Y (en) * | 1998-04-03 | 2000-01-12 | 杨睿 | Practical wireless cycle monitoring system for working condition of oil-producing machine |
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| CN1315613A (en) | 2001-10-03 |
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