CN110265990A - A kind of more wells coupling common DC bus voltage balance controls of pumping unit and fault detection method - Google Patents
A kind of more wells coupling common DC bus voltage balance controls of pumping unit and fault detection method Download PDFInfo
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- CN110265990A CN110265990A CN201810197917.3A CN201810197917A CN110265990A CN 110265990 A CN110265990 A CN 110265990A CN 201810197917 A CN201810197917 A CN 201810197917A CN 110265990 A CN110265990 A CN 110265990A
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- pumping unit
- fault
- wells
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- 238000005086 pumping Methods 0.000 title claims abstract description 28
- 238000001514 detection method Methods 0.000 title claims abstract description 20
- 230000008878 coupling Effects 0.000 title claims abstract description 7
- 238000010168 coupling process Methods 0.000 title claims abstract description 7
- 238000005859 coupling reaction Methods 0.000 title claims abstract description 7
- 238000006243 chemical reaction Methods 0.000 claims abstract description 19
- 238000000034 method Methods 0.000 claims abstract description 10
- 230000006641 stabilisation Effects 0.000 claims abstract description 5
- 238000011105 stabilization Methods 0.000 claims abstract description 5
- 230000005540 biological transmission Effects 0.000 claims description 13
- 230000005611 electricity Effects 0.000 claims description 8
- 230000005404 monopole Effects 0.000 claims description 6
- 238000011897 real-time detection Methods 0.000 claims description 4
- 238000007405 data analysis Methods 0.000 claims description 3
- 230000001681 protective effect Effects 0.000 claims description 3
- 230000011218 segmentation Effects 0.000 claims description 3
- 210000002268 wool Anatomy 0.000 abstract 1
- 239000003129 oil well Substances 0.000 description 3
- 241000208340 Araliaceae Species 0.000 description 2
- 235000005035 Panax pseudoginseng ssp. pseudoginseng Nutrition 0.000 description 2
- 235000003140 Panax quinquefolius Nutrition 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 235000008434 ginseng Nutrition 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 230000009194 climbing Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/22—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for distribution gear, e.g. bus-bar systems; for switching devices
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J1/00—Circuit arrangements for dc mains or dc distribution networks
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Control Of Eletrric Generators (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
The present invention provides a kind of more wells coupling common DC bus voltage balance controls of pumping unit and fault detection method, is a kind of position that can be realized the more well common DC bus voltage stabilizations of pumping unit and detect faulty line and the method cut off.The system that the present invention is applicable in is made of three-phase alternating-current supply, transformer, fairing, DC bus, breaker, frequency conversion terminal, measure voltage &, controller, rod-pumped well etc., by the way of both end power supplying, increase the electrical stability of system.By detecting DC bus-bar voltage, frequency conversion terminal output frequency is adjusted, to control the speed that pumping unit draws electric energy, maintains busbar voltage in the reasonable scope；Internal fault external fault is judged by power directional element, then calculates the ratio of voltage magnitude and current differential, is determined the specific location that failure occurs, is acted corresponding breaker, faulty line is cut off, protect the normal operation of rod-pumped well on other regular links.The present invention is suitable for the heavy wool well group control system of both end power supplying.
Description
Technical field
The invention belongs to the more wells of pumping unit to couple common DC bus team control field, and in particular to a kind of more well couplings of pumping unit
Common DC bus voltage balance control and fault detection method.
Technical background
For the electric energy loss for reducing power supply line, the utilization rate of route electric energy is improved, while preventing near oil fields resident from stealing
Electrical phenomena, present oil field mostly use DC bus powered form.The electric energy of power distribution network transmission is rectified after transformer pressure-reducing
Device becomes direct current, and electric energy constitutes DC loop along positive and negative busbar, and more mouthfuls of pumping units are connected in parallel on DC loop, through inverter
Inversion is exchange driving pumping-unit motor work.But DC power transmission line is mostly single-ended power at this stage, when route section is sent out
When raw failure, needs to disconnect in whole route, seriously affect the normal work of rod-pumped well on remaining normal line section.
Since stroke and jig frequency have differences more mouthfuls of pumping units during the work time, will cause when drawing electric energy from power grid
Power grid energy fluctuation.To guarantee that power grid electric energy is run in reasonable waving interval, need to carry out the working condition of each oil well real-time
Adjustment, makes its operation of avoiding the peak hour.Pumping unit is in the process of running due to the variation of load, and the jig frequency and energy consumption of up-down stroke are also therewith
Variation.The Voltage Drop caused by power grid when to avoid more wells from running simultaneously generallys use the mode of artificial not timing tune ginseng.But
It is artificial to adjust ginseng often in hysteretic state since pumping unit working condition changes irregularities.
Summary of the invention
The defect that present invention aims to solve the prior art provides a kind of more well coupling common DC bus voltages of pumping unit
Balance route and fault detection method maintain the stabilization of DC bus line voltage distribution, effectively excision faulty line, reduce because of route
Failure and cause shut down motor-pumped well quantity.
To achieve the above object, the invention adopts the following technical scheme:
The rod-pumped well group control system by three-phase alternating-current supply, transformer, fairing, DC bus, breaker,
The composition such as frequency conversion terminal, measure voltage &, controller, rod-pumped well, more rod-pumped well frequency conversion terminals are matched and are hung over
Carry out team control on DC bus, realize more rod-pumped wells in group control system fall generate electricity can circulation it is shared, reduce net and survey harmonic wave
Pollution improves the power factor of system work.
The DC bus is made of positive and negative two buses, using the power supply mode of both end power supplying, according to the length of route
DC bus segmentation is protected, the protective devices such as every section of transmission line of electricity two sides installing breaker improve system stable operation
Ability.
The DC bus-bar voltage Balance route can be realized the stabilization of DC bus-bar voltage, and the range of voltage fluctuation is tieed up
It holds in reasonable range, implementation step are as follows:
Step 1: the stroke of the voltage of detection device real-time detection DC bus and each motor-pumped well motor, jig frequency will test
Signal passes controller back by information transmission modular in real time and carries out logic judgment and data analysis；
Step 2: whether in the normal range judging busbar voltage, issue control signal if voltage is beyond normal range (NR)
Each motor-pumped well frequency conversion terminal is controlled；
Step 3: when busbar voltage is below zone of reasonableness, frequency conversion terminal is issued by information transmission modular and is instructed,
Output frequency is reduced, postpones pumping unit and draws electric energy speed；When busbar voltage is more than zone of reasonableness, mould is transmitted by information
Block issues frequency conversion terminal and instructs, and improves output frequency, accelerates pumping unit and draws electric energy speed；When busbar voltage tends to be steady,
Then keep the currently monitored state.
The rod-pumped well group control system DC bus fault detection method can effectively judge that monopole occurs for DC bus
Failure or bipolar failure, when steady-state operation, positive and negative interpolar voltage swing is equal, contrary；When monopole failure, a pole tension
It is zero, twice when another pole tension value is stable state；When bipolar failure, two pole tensions are almost equal to zero.
Troubles inside the sample space or external area error are judged by power directional element, the direction of route is directed toward in setting by bus
For positive direction, when breaker action message when various failures occurring in the positive direction, and breaking down in the reverse direction reliably not
Movement.
The mathematic(al) representation of the ratio approach of the voltage magnitude and current differential are as follows:
Wherein, up、unRespectively positive and negative anodes busbar voltage, ipBe positive electrode current, Ls、LmRoute respectively in unit length
Self-inductance and mutual inductance；
Operation equation are as follows:
Wherein, kset=(Ls-Lm) l, 1 represents the overall length of route.
Occur interpolar metallicity failure when, the ratio of short time internal fault voltage across poles amplitude and current differential mainly with therefore
Hinder distance dependent, the place on line and fault distance occurred by compared with setting valve, can determine failure, effectively excision event
Hinder route.
A kind of more well coupling common DC bus voltage balance controls of pumping unit of the present invention and fault detection method, as direct current mother
Line voltage fluctuates when except allowed band, changes output frequency by controlling each rod-pumped well frequency conversion terminal, adjusts pumping unit
The speed for drawing electric energy makes busbar voltage reach stable；DC bus uses both end power supplying form, improves the stability of power supply；
The position that failure occurs is judged by the ratio approach of voltage magnitude and current differential, and the protection elements such as action breaker are by failure
Route excision, maintains the normal operation of remaining oil well.
Detailed description of the invention
Fig. 1 is the oil well team control schematic diagram of DC bus both end power supplying, is abstract of description attached drawing；
Fig. 2 is DC bus-bar voltage Balance route flow chart；
Fig. 3 is that interpolar failure schematic diagram occurs for DC line section, and 3-1 is positive DC bus in figure, and 3-2 is negative direct current mother
Line, 3-3 are filter capacitor, A and B two o'clock is short dot, and dotted line is the direction of short circuit current；
Fig. 4 is that DC bus fault detects and cuts off flow chart.
Specific embodiment
In order to more specifically illustrate the present invention, with reference to the accompanying drawing and specific embodiment to technical solution of the present invention into
Row detailed description.
As shown in Figure 1, targeted rod-pumped well group control system of the invention uses the power supply mode of both end power supplying, by three-phase
AC power source 1-1, transformer 1-2, fairing 1-3, DC bus 1-4, breaker 1-5, frequency conversion terminal 1-6, voltage and current
The composition such as detection module, controller 1-7, rod-pumped well 1-8, more rod-pumped well frequency conversion terminals are enterprising with DC bus is hung over
Row team control, realize more rod-pumped wells in group control system fall generate electricity can circulation it is shared, reduce net and survey harmonic pollution, improve system
The power factor of work.
DC bus is made of positive and negative two-phase, is protected DC bus segmentation according to the length of route, every section of transmission of electricity
The protective devices such as breaker are installed in route two sides, improve the ability of system stable operation.
As shown in Fig. 2 flow chart, DC bus-bar voltage Balance route can be realized the stabilization of DC bus-bar voltage, by voltage
The range of fluctuation maintains in reasonable range, implementation step are as follows:
Step 1: the stroke of the voltage of detection device real-time detection DC bus and each motor-pumped well motor, jig frequency will test
Signal passes controller back by information transmission modular in real time and carries out logic judgment and data analysis；
Step 2: whether in the normal range judging busbar voltage, issue control signal if voltage is beyond normal range (NR)
Each motor-pumped well frequency conversion terminal is controlled；
Step 3: when busbar voltage is below zone of reasonableness, frequency conversion terminal is issued by information transmission modular and is instructed,
Output frequency is reduced, postpones pumping unit and draws electric energy speed；When busbar voltage is more than zone of reasonableness, mould is transmitted by information
Block issues frequency conversion terminal and instructs, and improves output frequency, accelerates pumping unit and draws electric energy speed；When busbar voltage tends to be steady,
Then keep the currently monitored state.
As shown in Figure 3, it is contemplated that the coupled relation between positive and negative anodes circuit can obtain equation:
In formula: up、unRespectively positive and negative pole tension, ip、inRespectively positive and negative electrode current, Rs、Rm、Ls、LmRespectively represent route
The self-resistance of unit length, mutual resistance, self-inductance, mutual inductance, x are the fault distance of this section of route.
When troubles inside the sample space, fault current directly flows to line protection installation place by fault point, so positive and negative anodes bus
Size of current is equal, contrary, it may be assumed that
ip=-in(2)
Formula (2) substitution formula (1) can be obtained:
Formula (3), which convert, to be obtained:
Since under the bipolar fault condition of DC bus, interelectrode capacity is discharged rapidly, DC voltage is reduced rapidly when failure,
DC current quickly increases.So that current differential value dipMuch larger than current amplitude ip, formula (4) can simplify are as follows:
Formula (5) is also the mathematic(al) representation of the ratio approach of voltage magnitude and current differential, as Protection criteria.
Operation equation are as follows:
Wherein, setting valve kset=(Ls-Lm) l, 1 represents the overall length of route.
For the overall length of protection circuit, remote ground fault constantly relay fail is prevented.In the condition that boundary element is housed
Under, the setting method in formula (6) can be optimized, multiplied by one on the basis of total track length and distributed inductance product
COEFFICIENT K slightly larger than 1rel, to increase the sensitivity of protection, expand protection scope.
Total track length adjusting are as follows:
Lset=KrelLsl(7)
With the increase of fault distance, the climbing speed of electric current is substantially reduced in fault loop, can not ignore failure pole again
The ratio of current amplitude and current differential, so that formula (5) is no longer set up, voltage value and current differential used by Protection criteria
Ratio will be greater than the product of fault distance and distributed inductance in hypothesis, and with the increase of fault distance, with theoretical value offset
It is bigger, so the method for the invention is suitable for short-distance and medium-distance transmission line of electricity.
As shown in Fig. 4 flow chart, rod-pumped well group control system DC bus fault detection method can effectively judge direct current
Monopole failure or bipolar failure occur for bus, and when steady-state operation, positive and negative interpolar voltage swing is equal, contrary；Monopole event
When barrier, a pole tension is zero, twice when another pole tension value is stable state；When bipolar failure, two pole tensions are almost equal to zero.
Troubles inside the sample space or external area error are judged by power directional element, the direction of route is directed toward in setting by bus
For positive direction, when breaker action message when various failures occurring in the positive direction, and breaking down in the reverse direction reliably not
Movement.
When interpolar metallicity failure occurs for the present invention, the ratio master of short time internal fault voltage across poles amplitude and current differential
Place on line and fault distance related with fault distance, being occurred by compared with setting valve, can determine failure, effectively
Cut off faulty line, guarantee other regular links the stable operation with motor-pumped well.
The foregoing is only a preferred embodiment of the present invention, but scope of protection of the present invention is not limited thereto,
In the technical scope disclosed by the present invention, any changes or substitutions that can be easily thought of by anyone skilled in the art,
It should be covered by the protection scope of the present invention.Therefore, protection scope of the present invention should be with scope of protection of the claims
Subject to.
Claims (7)
1. a kind of more wells of pumping unit couple common DC bus voltage balance control and fault detection method, it is based on both-end direct current
The more well group control systems of the pumping unit of power supply are realized by the way of frequency conversion terminal output frequency using real-time detection busbar voltage and adjusting
The equilibrium of busbar voltage；Internal fault external fault is judged by power directional element, by the ratio for calculating voltage magnitude and current differential
The method of value determines the specific location that failure occurs, acts corresponding breaker, protect rod-pumped well on other regular links
It operates normally.
2. the more wells of a kind of pumping unit according to claim 1 couple common DC bus voltage balance control and fault detection side
Method, it is characterised in that: the rod-pumped well group control system by three-phase alternating-current supply, transformer, fairing, DC bus,
The composition such as breaker, frequency conversion terminal, measure voltage &, controller, rod-pumped well, by more rod-pumped well frequency conversion terminals
Team control is carried out on DC bus with hanging over, realize more rod-pumped wells in group control system fall generate electricity can circulation it is shared, reduce net
Harmonic pollution is surveyed, the power factor of system work is improved.
3. a kind of more wells coupling common DC bus voltage balance controls of a pumping unit according to claim 1 and fault detection
Method, it is characterised in that: the DC bus is made of positive and negative two buses, using the power supply mode of both end power supplying, according to line
The length on road protects DC bus segmentation, and the protective devices such as breaker are installed in every section of transmission line of electricity two sides, improves system
The ability of system stable operation.
4. the more wells of a kind of pumping unit according to claim 1 couple common DC bus voltage balance control and fault detection side
Method, it is characterised in that: the DC bus-bar voltage Balance route can be realized the stabilization of DC bus-bar voltage, by voltage fluctuation
Range maintains in reasonable range, implementation step are as follows:
Step 1: the stroke of the voltage of detection device real-time detection DC bus and each motor-pumped well motor, jig frequency will test signal
It passes controller back in real time by information transmission modular and carries out logic judgment and data analysis；
Step 2: whether in the normal range judging busbar voltage, control signal is issued if voltage is beyond normal range (NR) to each
Motor-pumped well frequency conversion terminal is controlled；
Step 3: when busbar voltage is below zone of reasonableness, frequency conversion terminal being issued by information transmission modular and is instructed, reduced
Output frequency postpones pumping unit and draws electric energy speed；When busbar voltage is more than zone of reasonableness, pass through information transmission modular pair
Frequency conversion terminal issues instruction, improves output frequency, accelerates pumping unit and draws electric energy speed；When busbar voltage tends to be steady, then protect
Hold the currently monitored state.
5. the more wells of a kind of pumping unit according to claim 1 couple common DC bus voltage balance control and fault detection side
Method, it is characterised in that: the rod-pumped well group control system DC bus fault detection method can effectively judge that DC bus is sent out
Raw monopole failure or bipolar failure, when steady-state operation, positive and negative interpolar voltage swing is equal, contrary；When monopole failure, one
Pole tension is zero, twice when another pole tension value is stable state；When bipolar failure, two pole tensions are almost equal to zero.
6. the more wells of a kind of pumping unit according to claim 1 couple common DC bus voltage balance control and fault detection side
Method, it is characterised in that: troubles inside the sample space or external area error are judged by power directional element, setting is directed toward route by bus
Direction be positive direction, when breaker action message when various failures occurring in the positive direction, and breaking down in the reverse direction
Reliably it is failure to actuate.
7. the more wells of a kind of pumping unit according to claim 1 couple common DC bus voltage balance control and fault detection side
Method, it is characterised in that: the mathematic(al) representation of the ratio approach of the voltage magnitude and current differential are as follows:
Wherein, up、unRespectively positive and negative anodes busbar voltage, ipBe positive electrode current, Ls、LmThe electricity certainly of route respectively in unit length
Sense and mutual inductance；
Operation equation are as follows:
Wherein, kset=(Ls-Lm) l, l represents the overall length of route.
Occur interpolar metallicity failure when, the ratio of short time internal fault voltage across poles amplitude and current differential mainly and failure away from
From place on line and fault distance related, occurred by compared with setting valve, can determine failure, effectively excision fault wire
Road, guarantee other regular links the stable operation with motor-pumped well.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810197917.3A CN110265990B (en) | 2018-03-12 | 2018-03-12 | Multi-well coupling common direct current bus voltage balance control and fault detection method for oil pumping unit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810197917.3A CN110265990B (en) | 2018-03-12 | 2018-03-12 | Multi-well coupling common direct current bus voltage balance control and fault detection method for oil pumping unit |
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| Publication Number | Publication Date |
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| CN110265990A true CN110265990A (en) | 2019-09-20 |
| CN110265990B CN110265990B (en) | 2023-11-14 |
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2018
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|---|---|---|---|---|
| CN103004048A (en) * | 2010-06-14 | 2013-03-27 | Abb研究有限公司 | Fault protection of HVDC transmission lines |
| CN103500261A (en) * | 2013-10-22 | 2014-01-08 | 国家电网公司 | Method for fault simulation of direct current transmission system |
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| CN110265990B (en) | 2023-11-14 |
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