CN205489522U - Beam -pumping unit direct current distribution system - Google Patents
Beam -pumping unit direct current distribution system Download PDFInfo
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- CN205489522U CN205489522U CN201520931491.1U CN201520931491U CN205489522U CN 205489522 U CN205489522 U CN 205489522U CN 201520931491 U CN201520931491 U CN 201520931491U CN 205489522 U CN205489522 U CN 205489522U
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Abstract
The utility model discloses a beam -pumping unit direct current distribution system, including high voltage generating line, transformer, low pressure ac bus, beam -pumping unit, still include two -way change of current unit, dc bus and a plurality of direct current motor, wherein, a plurality of direct current motor connect in parallel on the dc bus, and the drive divide into propradation and decline state rather than the beam -pumping unit work of matcing, when a plurality of direct current motor were in the propradation and need the electric energy, the ac inversion that two -way change of current unit will come from low pressure ac bus be the direct current, transmitted to the dc bus to supply power for a plurality of direct current motor, when a plurality of direct current motor were in the decline state and generate electricity, electric energy contravariant that two -way change of current unit will fall the substation productions was fed back extremely low pressure ac bus. The utility model discloses a direct current motor has replaced AC motor, big, the easy adjustment of torque, adopt the filtering unit to carry out filtering, improve dc bus stability, adopt the electric energy of the energy storage unit storage production of falling the substation, improved the electric energy rate of utilization.
Description
Technical field
This utility model relates to a kind of distribution system, particularly to a kind of oil pumper direct-flow distribution system, belongs to distribution network automated technical field.
Background technology
At present, oil pumper is the capital equipment in producing that recovers the oil at present, and it is made up of motor, reduction box and quadric chain (including crank, connecting rod and walking beam) etc., and quantity reaches more than 100,000.The oil field of China mostly is stripper well, and electricity used for oil extractor accounts for the 40% of oil field total electricity consumption, and operational efficiency is relatively low, and waste of energy is big, so needing badly, pumping unit system is carried out reducing energy consumption.
Oil pumper is potential energy loading high, and when down stroke, motor there will be the rotor speed synchronous rotational speed more than motor, makes motor become Generator Status, this state the most generating state.At the electric energy that the time of falling generating state produces, in prior art, the electric energy processing method generated electricity of falling has three kinds: one to be the method using dynamic braking, is consumed by the energy resistance of generating, this mode advantage of lower cost, but waste electric energy；Two is feedback mode, and by the controllable rectifier bridge of feedback unit or four-quadrant frequency converter by electric energy feedback electrical network, this mode cost is the highest, more serious to the harmonic effects of electrical network, is not suitable for popularization and application；Three is to use common DC bus mode, transfers energy to other load and uses, and this mode low cost is the most energy-conservation, but uses at most applications and have limitation.
Existing a kind of intelligent controlling system for beam-pumping unit based on optimum jig frequency identification discloses intelligence system and bypath system two parts that intelligent controlling system for beam-pumping unit is made up of special converter for pumping unit, direct current reactor and intelligent control card.Intelligence system, by the electric current of converter and the instantaneous voltage of voltage detection circuit detection motor and transient current, calculates the instantaneous power (containing negative power) of motor, communicatively instantaneous power is sent to intelligent control card.Instantaneous power is for data processing by intelligent control card, obtains the jig frequency electrisity consumption of oil pumper.Oil pumper jig frequency power consumption under different jig frequencies detected, by calculating the jig frequency power consumption of optimum jig frequency and correspondence based on Liquid output maximized optimum jig frequency identification mathematical model, complete the self study to oil well condition.Based Intelligent Control card control converter runs in frequency corresponding to optimum jig frequency, and the situation of change to jig frequency power consumption of detection carries out closed loop control to oil pumper in real time, follows the tracks of the feed flow situation of down-hole, it is achieved for adopting balance, increasing production and improying productivity, save energy and reduce the cost.But the cost that this programme uses patent converter can be higher, asynchronous motor is owing to often processing the state that power factor is relatively low simultaneously, also can cause waste of energy.Owing to dc motor has good starting, braking and speed adjusting performance；Energy quickly starting and braking, forward and backward；Can smooth in the broadest scope and governing speed economically.When oil pumper is transformed, cause the attention of people.
Another kind of optimized energy-saving controller for combination type pumping unit includes dc bus, frequency controller and transducer, dc bus input is provided with rectification accumulator, is connected in parallel to multiple Way of Regenerating Energy Feedback device on this rectification accumulator input.When direct current bus bar source is crossed and automatically worked higher than the power supply of Way of Regenerating Energy Feedback device, described rectification accumulator is defeated by frequency controller superfluous electric energy through dc bus, and the converted device of frequency controller transports oil pumper；The generation of shutdown phenomenon because causing when DC bus-bar voltage is too high can be avoided in prior art because of converter.Meanwhile, because of rectification accumulator superfluous power transportation to oil pumper, the effect of energy-conservation electric energy can be reached.The program is due to the existence of frequency conversion equipment so that the harmonic wave of bus increases, and the life-span of motor reduces, and equipment is relatively costly simultaneously, adds the cost of enterprise.Although it addition, the energy of motor generating is alleviated to a certain extent, but there is also the space continuing to improve.
Utility model content
The technical problems to be solved in the utility model is: (1) uses direct current generator to substitute alternating current generator and drives oil pumper work；(2) quality of power supply of dc bus is improved；(3) the electric energy reasonable employment that generating of being fallen when down stroke works by direct current generator produces.
For realizing above-mentioned utility model purpose, this utility model provides a kind of oil pumper direct-flow distribution system, including high voltage AC bus, transformator, low-voltage alternating-current bus, oil pumper, the High Level AC Voltage of described high voltage AC bus is converted into low-voltage AC by described transformator, and it is transferred to described low-voltage alternating-current bus, also include two-way convertor unit, dc bus and multiple direct current generator, wherein, the plurality of direct current generator is connected in parallel on dc bus, drive matched oil pumper to work, be divided into propradation and decline state；
When the plurality of direct current generator be in propradation need electric energy time, the alternating current from described low-voltage alternating-current bus is converted to unidirectional current by described two-way convertor unit, and transmission to described dc bus is that the plurality of direct current generator is powered；
When the plurality of direct current generator be in decline state generate electricity time, described two-way convertor unit will fall the produced electric energy of generating and be reverse into alternating current, feed back to described low-voltage alternating-current bus.
More preferably, described two-way convertor unit is PWM rectifier.
More preferably, described oil pumper direct-flow distribution system also includes that filter unit, described filter unit are connected with described dc bus, and the positive pole of described filter unit is connected to positive direct-current bus, and the negative pole of described filter unit is connected to negative dc bus.
More preferably, described filter unit is electric capacity.
More preferably, described oil pumper direct-flow distribution system also includes that energy-storage units, described energy-storage units are connected with described dc bus, and the positive pole of described energy-storage units is connected to positive direct-current bus, and negative pole is connected to negative dc bus.
More preferably, described energy-storage units is accumulator battery.
More preferably, described energy-storage units is accumulator battery and capacitor.
More preferably, described capacitor and the described accumulator battery switching voltage when receiving electric energy are continuous print.
Compared with prior art, of the present utility model have the advantages that
(1) using the direct current generator being prone to speed governing to instead of alternating current generator, torque is big, improves efficiency；
(2) use filter unit to be filtered by the produced electric energy of generating, improve dc bus stability；
(3) use the energy-storage units storage produced electric energy of generating, when direct current generator needs, then discharge, instead of conventional braking resistor consumption, improve electric energy utilization rate；
(4) use dc bus can improve transmission range, greatly improve efficiency of transmission.
Accompanying drawing explanation
Fig. 1 is oil pumper direct-flow distribution system block diagram in prior art；
Fig. 2 is a kind of oil pumper direct-flow distribution system block diagram that this utility model provides；
Fig. 3 is in this utility model embodiment one, for the oil pumper direct-flow distribution system principle schematic of direct current generator；
Fig. 4 is in this utility model embodiment two, and that falls the produced electric energy of generating flows to schematic diagram.
Detailed description of the invention
Below in conjunction with the accompanying drawings and embodiment, detailed description of the invention of the present utility model is described in further detail.Following example are used for illustrating this utility model, but are not limited to scope of the present utility model.
As it is shown in figure 1, oil pumper direct-flow distribution system of the prior art, including: high voltage AC bus, transformator, low-voltage alternating-current bus, multiple alternating current generator and the oil pumper matched.Owing to the operating mode of oil well is more complicated, need alternating current generator is carried out speed governing, mostly introduce converter and carry out speed governing, can not store due to converter and discharge the electric energy generated electricity, bus high pressure can be caused to raise.
To this end, a kind of oil pumper direct-flow distribution system that this utility model provides, as in figure 2 it is shown, include high voltage AC bus, transformator, low-voltage alternating-current bus, two-way convertor unit, dc bus, multiple direct current generator and the oil pumper matched.The input of transformator is connected to high voltage AC bus, and its outfan is connected to low-voltage alternating-current bus.The input of two-way convertor unit is connected to low-voltage alternating-current bus, and outfan is connected to dc bus.Multiple direct current generators are parallel to dc bus, and drive the oil pumper of equivalent amount.
The operation principle of oil pumper direct-flow distribution system is as follows: the High Level AC Voltage from high voltage AC bus is converted to low-voltage AC by transformator, and transmits to low-voltage alternating-current bus.Two-way convertor unit gathers the low-voltage AC of low-voltage alternating-current bus and carries out rectification, forms the unidirectional current identical with the rated voltage of direct current generator, and transmission is to dc bus.It is connected in parallel on after multiple direct current generators of dc bus switch on power and can operate, thus drive matched oil pumper to be operated.
Oil pumper operationally, pumping of the cycle that can fix under the driving of direct current generator, the oil of down-hole is delivered to ground.Within a cycle, along with the rise and fall of sucker rod, unidirectional current chance is operated in electronic/generating state, i.e. uphill process direct current generator and absorbs energy electric operation from dc bus；Being potential load at the load characteristic declining course direct motor, the negative pressure of down-hole makes the rotating speed of DC motor rotor more than synchronous rotational speed in addition, and now motor is in generating state, and mechanical energy is converted into electric energy feedback to electrical network.
But, if the electric energy of generation is directly fed back to electrical network, the quality of power supply of dc bus can be produced large effect, thus affect the normal work of other direct current generators.Common commutator, it is impossible to convert electric energy to alternating current and feed back to ac bus, can increase the voltage of dc bus further, damages the equipment being connected with dc bus.
Therefore, this utility model uses two-way convertor unit, is used for solving the problems referred to above.When direct current generator is operated in motoring condition, low-voltage AC can be converted into unidirectional current by this two-way convertor unit, it is provided that to direct current generator.When being operated in the quantity of direct current generator quantity redundant work direct current generator in uphill process during decline, DC bus-bar voltage now can be caused to raise, the most two-way convertor unit triggering work, by the converting direct-current power into alternating-current power of direct current generator generating, is fed back to low-voltage alternating-current bus.By the bi-directional conversion of two-way convertor unit, greatly improve utilization rate of electrical, moreover it is possible to prevent DC bus-bar voltage from raising to a certain extent, indirectly protect electrical equipment.
Preferably, two-way convertor unit of the present utility model uses PWM rectifier.As it is shown on figure 3, during PWM rectifier rectification, electric energy transmits to dc bus from low-voltage alternating-current bus；During PWM rectifier inversion, electric energy transmits to ac bus from dc bus.By said process, direct current generator can be solved when generating electricity, the problem that DC bus-bar voltage raises.
Two-way convertor unit of the present utility model can also use uncontrollable commutator exchange realization in parallel with inverter parallel device, uncontrollable commutator AC is connected to ac bus, DC side is connected to dc bus, and inverter ac side joint is connected to dc bus in ac bus, DC side.Exchange uncontrollable commutator and alternating current can be converted to unidirectional current, for DC bus powered.Such as the height of falling generated energy, cause DC bus-bar voltage high, then with inverter, unidirectional current is converted to alternating current, feeds back to low-voltage alternating-current bus.
Owing to multiple direct current generators are operated in different states, some is in decline process and falls to generate electricity, some is in uphill process needs electric energy, their quantity is the most equal, more or less, so, dc bus will be caused a certain degree of impact, produce substantial amounts of harmonic wave, have influence on other direct current generators.
This utility model is provided with filter unit in the side of dc bus, reduces the harmonic content entrained by electric energy produced of falling to generate electricity, enables the power supply quality of dc bus to be guaranteed, thus need not affect the performance of other direct current generators.
This electric capacity primarily serve the purpose of filtering, be not the unidirectional current of standard owing to falling the produced electric energy of generating, be fluctuation containing more harmonic wave, i.e. DC voltage.This electric capacity can absorb the electric energy exceeding DC bus-bar voltage, starts the effect of smooth the produced electric energy that generates electricity.
On the other hand, electric capacity can also store the electric energy that generates electricity of a part, stores unnecessary electric energy, and then the voltage of stable DC bus.When generating electricity, the voltage of DC generator is higher than DC bus-bar voltage, therefore can be electric capacity charging, store energy in electric capacity.When the direct current generator being in motoring condition is more, being i.e. in that upstroke oil pumper is more needs energy more, electric capacity releases energy and is supplied to direct current generator, makes DC bus-bar voltage stable, it is provided that the electric energy of better quality.
Under normal circumstances, in certain area, accessing the direct current generator of dc bus, it is generally equalized with the quantity being in down stroke to be in upstroke, and therefore the impact on dc bus is smaller.Increasing electric capacity and i.e. solve above-mentioned impact, now the utilization rate of the energy in distribution system is higher.
But, owing to the expense of the finite capacity of electric capacity, bulky capacitor or super capacitor is bigger.Or when the direct current generator quantity being in down stroke is much larger than the direct current generator quantity being in upstroke, now the impact on dc bus is the biggest.Now electric capacity has stored more electric energy, due to its finite capacity, it is impossible to deal with severe electric field environment now.Therefore also need to electric energy is processed.More preferably, this utility model is also provided with energy-storage units in the side of dc bus, and energy-storage units can store unnecessary electric energy further.Due to energy-storage units can bigger by Capacity design, therefore can well solve problem above.When the produced electric energy that falls to generate electricity is more, triggers energy-storage units and be operated storage electric energy.When the direct current generator being in upstroke state is more, discharges electric energy, thus ensure the voltage stabilization of dc bus.The more important thing is, the electric energy generated electricity can be made farthest to be utilized, it is to avoid utilize the situation of these electric energy of resistance consumption.
Preferably, energy-storage units of the present utility model uses accumulator battery, or accumulator battery and electric capacity.
If the capacity of energy-storage units is excessive, corresponding cost also can be increased.Therefore, this utility model, when the energy that energy-storage units stores reaches rated value, can start two-way convertor unit, now, two-way convertor unit will be converted into alternating current by the produced electric energy of generating, and feed back to low-voltage alternating-current bus.
The work process of the oil pumper direct-flow distribution system that this utility model provides is such that (1) when the quantity that multiple direct current generators are in upstroke state is more, two-way convertor unit will become unidirectional current from the AC rectification of low-voltage alternating-current bus, and transmit to dc bus, for multiple direct current generators；(2) when the quantity that multiple direct current generators are in down generating state is more, the voltage of dc bus can be caused to raise, the most two-way convertor unit carries out inversion, is alternating current by DC inverter, and feeds back to described low-voltage alternating-current bus.
As shown in Figure 4, transformator High Level AC Voltage is carried out conversion generate low-voltage AC be transferred to low-voltage alternating-current bus.Low-voltage AC is carried out rectification by PWM rectifier, forms unidirectional current, and transmits to dc bus.After the energising of multiple direct current generators, matched oil pumper is driven to be operated.
When being in propradation and being generally equalized with the direct current generator quantity declining state, the most whole distribution system is in relative balance state, the electric energy of the direct current generator generating being i.e. in decline state can be utilized by the direct current generator being in propradation, and the utilization rate of electric energy is higher.
As shown in Figure 4, when propradation and the direct current generator quantity declining state are unequal, and when correlated measure is bigger, now distribution system is in unbalanced state.An a fairly large number of side, when propradation, needs electric energy more；When this Partial DC motor is in decline state, can generate electricity again and feed back to dc bus, can strong influence dc bus.
When this Partial DC motor is in decline state, the generating electric energy that falls is more, and now the unidirectional current of feedback can be filtered by electric capacity, absorbs a part of electric energy simultaneously, if being now switched to propradation, electric capacity discharges to dc bus.If electric capacity receives electric capacity to the rated value of self, also back electrical energy is to dc bus endlessly, and now accumulator battery starts energy storage, in like manner, if being now switched to propradation, accumulator battery is discharged to dc bus, after having discharged, electric capacity also discharges to dc bus.If when accumulator battery storage electric energy is to rated value, also having the electric energy of feedback, the most then needing to trigger PWM rectifier so that it is be operated in inverter mode, will DC inverter be that alternating current feeds back to low-voltage alternating-current bus.By process above, make the energy generated electricity farthest be utilized, thus solve the problem utilizing braking resistor to consume the waste of energy that electric energy causes in prior art.
It can thus be seen that this utility model is when storing electric energy, it is divided into three phases: when the produced electric energy that falls to generate electricity is less, electric capacity storing, now accumulator battery does not works；When electric energy is more, when the capacity of electric capacity is expired, now accumulator battery work, continues to receive unnecessary electric energy；When accumulator battery can not store electric energy, now trigger PWM rectifier and be operated, unidirectional current is converted to alternating current and is fed back to electrical network.
Certainly, when direct current generator needs more electric energy, first the electric energy of electric capacity with accumulator battery storage being supplied to direct current generator, period insufficient section is provided by dc bus.After electric capacity and accumulator battery have discharged, then provided by dc bus completely.
By being divided into the storage electric energy of three levels, and release electric energy, this utility model can be use up the electric energy farthest utilizing generating, the most also be stabilized the voltage of dc bus, enable direct current generator normally to work.
In sum, after AC asynchronous motor is replaced by dc motor by this utility model, it transform former AC distribution net as DC distribution net.Under former low-voltage alternating-current bus, accessing two-way convertor unit, AC energy can be changed into direct current energy, access the oil pumper of certain area under dc bus, carry out unifying power supply, dc bus is that the direct current oil pumper accessed is powered.And electric energy can two-way circulate, oil pumper is in the time of falling generating state, and dc bus can collect unnecessary electric energy, powers for other oil pumper.When accessing electric capacity under dc bus, there is filter action, filter harmonic wave and improve DC bus powered quality.Accessing accumulator battery under dc bus, unnecessary energy storage, in accumulator battery, discharges needs electric energy when, can improve DC bus-bar voltage stability, improves the quality of power supply.
Embodiment of above is merely to illustrate this utility model; and be not limitation of the utility model; those of ordinary skill about technical field; in the case of without departing from spirit and scope of the present utility model; can also make a variety of changes and modification; the technical scheme of the most all equivalents falls within category of the present utility model, and scope of patent protection of the present utility model should be defined by the claims.
Claims (8)
1. an oil pumper direct-flow distribution system, including high voltage AC bus, transformator, low-voltage alternating-current bus, oil pumper, the High Level AC Voltage of described high voltage AC bus is converted into low-voltage AC by described transformator, and it is transferred to described low-voltage alternating-current bus, it is characterized in that: also including two-way convertor unit, dc bus and multiple direct current generator, wherein, the plurality of direct current generator is connected in parallel on dc bus, drive matched oil pumper to work, be divided into propradation and decline state；
When the plurality of direct current generator be in propradation need electric energy time, the alternating current from described low-voltage alternating-current bus is converted to unidirectional current by described two-way convertor unit, and transmission to described dc bus is that the plurality of direct current generator is powered；
When the plurality of direct current generator be in decline state generate electricity time, described two-way convertor unit will fall the produced electric energy of generating and be reverse into alternating current, feed back to described low-voltage alternating-current bus.
2. oil pumper direct-flow distribution system as claimed in claim 1, it is characterised in that
Described two-way convertor unit is PWM rectifier.
3. oil pumper direct-flow distribution system as claimed in claim 1, it is characterised in that
Described oil pumper direct-flow distribution system also includes that filter unit, described filter unit are connected with described dc bus, and the positive pole of described filter unit is connected to positive direct-current bus, and the negative pole of described filter unit is connected to negative dc bus.
4. oil pumper direct-flow distribution system as claimed in claim 3, it is characterised in that
Described filter unit is electric capacity.
5. oil pumper direct-flow distribution system as claimed in claim 1, it is characterised in that
Described oil pumper direct-flow distribution system also includes that energy-storage units, described energy-storage units are connected with described dc bus, and the positive pole of described energy-storage units is connected to positive direct-current bus, and negative pole is connected to negative dc bus.
6. oil pumper direct-flow distribution system as claimed in claim 5, it is characterised in that
Described energy-storage units is accumulator battery.
7. oil pumper direct-flow distribution system as claimed in claim 5, it is characterised in that
Described energy-storage units is accumulator battery and capacitor.
8. oil pumper direct-flow distribution system as claimed in claim 7, it is characterised in that
Described capacitor and the described accumulator battery switching voltage when receiving electric energy are continuous print.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201520931491.1U CN205489522U (en) | 2015-11-19 | 2015-11-19 | Beam -pumping unit direct current distribution system |
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| CN201520931491.1U CN205489522U (en) | 2015-11-19 | 2015-11-19 | Beam -pumping unit direct current distribution system |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106786486A (en) * | 2016-12-22 | 2017-05-31 | 北京群菱能源科技有限公司 | A kind of mixed power supply system and its method for oil pumper |
| CN106877314A (en) * | 2017-03-10 | 2017-06-20 | 山东大学 | A kind of many electric power electric transformer tractive power supply systems of low-pressure side common DC bus |
| CN110190647A (en) * | 2019-05-31 | 2019-08-30 | 国网天津市电力公司 | A kind of 10kV power distribution network does not have a power failure electric power operation car |
| CN113517828A (en) * | 2021-06-03 | 2021-10-19 | 四川宏华电气有限责任公司 | Double-system oil rig electric drive system |
-
2015
- 2015-11-19 CN CN201520931491.1U patent/CN205489522U/en active Active
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106786486A (en) * | 2016-12-22 | 2017-05-31 | 北京群菱能源科技有限公司 | A kind of mixed power supply system and its method for oil pumper |
| CN106877314A (en) * | 2017-03-10 | 2017-06-20 | 山东大学 | A kind of many electric power electric transformer tractive power supply systems of low-pressure side common DC bus |
| CN106877314B (en) * | 2017-03-10 | 2023-11-21 | 山东大学 | Multi-power electronic transformer traction power supply system with low-voltage side sharing direct current bus |
| CN110190647A (en) * | 2019-05-31 | 2019-08-30 | 国网天津市电力公司 | A kind of 10kV power distribution network does not have a power failure electric power operation car |
| CN113517828A (en) * | 2021-06-03 | 2021-10-19 | 四川宏华电气有限责任公司 | Double-system oil rig electric drive system |
| CN113517828B (en) * | 2021-06-03 | 2023-12-15 | 四川宏华电气有限责任公司 | Dual-system electric driving system for petroleum drilling machine |
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