CN108667246B - A kind of fracturing pump, which directly drives, uses linear motor - Google Patents
A kind of fracturing pump, which directly drives, uses linear motor Download PDFInfo
- Publication number
- CN108667246B CN108667246B CN201810566403.0A CN201810566403A CN108667246B CN 108667246 B CN108667246 B CN 108667246B CN 201810566403 A CN201810566403 A CN 201810566403A CN 108667246 B CN108667246 B CN 108667246B
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- Prior art keywords
- mover
- stator
- iron core
- linear motor
- fracturing pump
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K16/00—Machines with more than one rotor or stator
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K41/00—Propulsion systems in which a rigid body is moved along a path due to dynamo-electric interaction between the body and a magnetic field travelling along the path
- H02K41/02—Linear motors; Sectional motors
- H02K41/03—Synchronous motors; Motors moving step by step; Reluctance motors
- H02K41/031—Synchronous motors; Motors moving step by step; Reluctance motors of the permanent magnet type
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Electromagnetism (AREA)
- Linear Motors (AREA)
Abstract
The invention discloses a kind of fracturing pump directly drive linear motors, including the first stator, the first mover, the second stator, the second mover, third stator, third mover and the 4th stator being arranged successively, the structure of first stator and the 4th stator is identical, and the second stator is identical with the structure of third stator；The both ends of first mover, the second mover and third mover are attached by connecting rod respectively；First mover, the second mover and third mover include that two mover iron cores, multiple permanent magnets and a magnetic barrier, magnetic barrier are located between two mover iron cores, and multiple permanent magnets are located at the outer wall of two mover iron cores.Motor of the present invention is three Structure of mover, can shorten the length of motor relative to conventional dual-side flat plate type single action minor structure, and motor is made to be easier processing, installation and transport.Motor of the present invention uses permanent magnet excitation, can be improved electric efficiency and power factor, while machine winding is located on stator, convenient for cooling and threephase cable access.
Description
Technical field
The invention belongs to motor field, more particularly, to a kind of fracturing pump directly drive linear motor.
Background technique
Demand of the high speed development of today's society to the energy is increasing, and conventional fossil energy such as coal, petroleum and natural
The reserves of gas gradually decrease instead, therefore people have found that the resources such as many new energy such as combustible ice, shale gas are come successively again
Substitute traditional fossil energy.Shale gas is a kind of unconventional natural gas resource, and China has been realized in the scale of shale gas
Production becomes the third-largest shale gas producing country in the whole world.
The exploitation of shale gas needs to use hydraulic fracturing technology, which is mainly pumped by high pressure fracture by high pressure fracture liquid
It is passed into rammell, so that rock is generated crack using the extruding of highly pressurised liquid, adds filler for fracture support, such shale
Gas can be flowed out from crack.The core of the technology is to the fracturing pump by low-pressure liquid turns for highly pressurised liquid.It is conventional
Fracturing pump is mainly made of power end and fluid end two parts, and prime mover is rotated by reduction gearing band dynamic crankshaft, passes through crankshaft
The conduction of link mechanism drives plunger to do linear reciprocating motion to realize the sucking and exclusion of liquid.Conventional fracturing pump is due to subtracting
The presence of the mechanical structures such as fast gear-box and crankshaft rod structure, noise is big, reliability is low when leading to operation, while crankshaft-link rod
There are the inherent defects that output flow is uneven and pressure oscillation is big for structure.
In order to solve the problems, such as that conventional fracturing pump exists, publication No. is that the patent of invention of CN103208903A discloses one kind
Pump uses linear motor.The linear motor and plunger are connected directly, and drive plunger to do linear reciprocating motion by linear motor, can be with
Solve above-mentioned a series of problems.Its technical characteristic are as follows: use dual-side flat plate type structure, mover is by permanent magnet and iron core two parts
Constitute, stator is that bilateral structure contains there are two identical stator, be made of stator core and three-phase windings, by three-phase around
Group is passed through three-phase alternating current can form travelling-magnetic-field in air gap, and the magnetic fields that the travelling-magnetic-field and permanent magnet generate generate
Stable thrust.Defect existing for the technology are as follows: mesohigh large-flow plunger pump generally requires very big thrust, for motor
Speech, the thrust of output is bigger, and the volume of motor is bigger, since the motor is only dual-side flat plate type structure, can there is motor
The too long problem of length, motor length is too long to will lead to processing difficulties, while increasing the difficulty of transport and installation.Simultaneously because
The case where structure is cut-off there are iron core causes between core ends and permanent magnet there are End Force to generate force oscillation.
And because the asymmetry of three-phase windings spatially causes three opposite potentials asymmetric, so that generating very under loading condition
Big force oscillation.
Summary of the invention
Aiming at the above defects or improvement requirements of the prior art, the present invention provides a kind of fracturing pump directly drive straight-line electrics
Machine, thus solve conventional fracturing pump because mechanical link excessively existing for noise is big, reliability is low, because of crankshaft rod structure bring
The technical problem that output flow is uneven and pressure oscillation is big, motor is too long and force oscillation is big.
To achieve the above object, the present invention provides a kind of fracturing pump directly drive linear motor, including be arranged successively
One stator, the first mover, the second stator, the second mover, third stator, third mover and the 4th stator,
The structure of first stator and the 4th stator is identical, and the second stator is identical with the structure of third stator；
The both ends of first mover, the second mover and third mover are attached by connecting rod respectively；First mover,
Second mover and third mover include that two mover iron cores, multiple permanent magnets and a magnetic barrier, magnetic barrier are located at two mover iron
Between core, multiple permanent magnets are located at the outer wall of two mover iron cores.
Further, two mover iron cores of the first mover are from top to bottom followed successively by the first mover iron core and the second mover iron
Two mover iron cores of core, the second mover are from top to bottom followed successively by third mover iron core and the 4th mover iron core, third mover
Two mover iron cores are from top to bottom followed successively by the 5th mover iron core and the 6th mover iron core,
The first mover iron core is identical as the permanent magnet arrangement on the 6th mover iron core outer wall, the first mover iron core and
Permanent magnet arrangement position on two mover iron core outer walls differs λ, the permanent magnetism on the second mover iron core and the 4th mover iron core outer wall
Body arrangement position differs λ, and the permanent magnet magnetization on the second mover iron core and third mover iron core outer wall is contrary, the 4th mover
Permanent magnet magnetization on iron core and the 5th mover iron core outer wall is contrary.
Further, λ=2m τp±2/3τp, wherein τpIt is permanent magnet pole away from m is positive integer.
Further, the first stator, the second stator, third stator and the 4th stator include stator core and three-phase around
Group.
Further, the three-phase windings axis of the first stator and the 4th stator is overlapped.
Further, the first stator, the second stator, third stator three-phase windings axis be not overlapped mutually.
Further, three-phase windings are Circular Winding, single layer lap winding or the double-deck lap winding.
Further, the material of magnetic barrier is non-magnet material, and the material of the permanent magnet is neodymium iron boron, SmCo, alnico
Or ferrite, mounting means of the permanent magnet on mover iron core be surface-mount type, it is embedded or alternately pole formula.
Further, the first mover, the direction of motion of the second mover and third mover and speed moment keep identical, and first
With the speed planning curvilinear motion of triangular wave or trapezoidal wave when mover, the second mover and third mover work.
Further, when linear motor is applied to fracturing pump, the plunger that the mover of linear motor directly drives fracturing pump is done
Linear reciprocating motion.
In general, through the invention it is contemplated above technical scheme is compared with the prior art, can obtain down and show
Beneficial effect:
(1) motor of the present invention is three Structure of mover, can shorten electricity relative to conventional dual-side flat plate type single action minor structure
The length of machine makes motor be easier to process, install and transport.Motor of the present invention uses permanent magnet excitation, can be improved motor effect
Rate and power factor, while machine winding is located on stator, convenient for cooling and threephase cable access.
(2) relative position of the present invention by the permanent magnet of three movers of change, the end tooth socket for generating three movers
There are phase differences for power, so as to weaken overall End Force.Three-phase windings of the present invention are spatially symmetrical, three opposite electricity
Gesture is symmetrical, can reduce force oscillation.
(3) present invention does linear reciprocating motion by the plunger that linear motor rotor directly drives fracturing pump, can remove
Reduction gearing and crankshaft connecting rod system to improve system effectiveness and reliability, while reducing noise.The normal work of mover of the present invention
With triangular wave or trapezoidal wave speed planning curvilinear motion when making, when more linear motor units of use are transported according to certain phase difference
When row, it can theoretically guarantee that the uniform pressure of output flow is constant.
Detailed description of the invention
Fig. 1 is a kind of structural schematic diagram of fracturing pump provided in an embodiment of the present invention directly drive linear motor；
Fig. 2 is a kind of fracturing pump provided in an embodiment of the present invention directly three Structure of mover schematic diagrames in drive linear motor；
In all the appended drawings, identical appended drawing reference is used to denote the same element or structure, in which:
1 is the first stator, and 2 be the second stator, and 3 be third stator, and 4 be third stator, and 5 be the first mover, and 6 is dynamic for second
Son, 7 be third mover, and 8 be winding, and 9 be permanent magnet, and 10 be the first mover iron core, and 11 be the second mover iron core, and 12 is dynamic for third
Sub- iron core, 13 be the 4th mover iron core, and 14 be the 5th mover iron core, and 15 be the 6th mover iron core, and 16 hinder for magnetic, and 17 connect for first
Extension bar, 18 be the second connecting rod.
Specific embodiment
In order to make the objectives, technical solutions, and advantages of the present invention clearer, with reference to the accompanying drawings and embodiments, right
The present invention is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, and
It is not used in the restriction present invention.As long as in addition, technical characteristic involved in the various embodiments of the present invention described below
Not constituting a conflict with each other can be combined with each other.
The invention proposes a kind of fracturing pump, directly drive linear motor, the plunger which can directly drive fracturing pump are done directly
Line moves back and forth, and eliminates extra mechanical structure, the operational efficiency and reliability of system can be improved.The special knot of the motor
Structure can reduce motor length, easy to process, installation and transport.The relative position that the motor passes through change rotor permanent magnet simultaneously
And stator winding transposition can reduce motor thrust fluctuation, to keep output flow more uniform.
As shown in Figure 1, the present invention provides a kind of fracturing pump directly drive linear motors, including the first stator being arranged successively
1, the first mover 5, the second stator 2, the second mover 6, third stator 3, third mover 7 and the 4th stator 4,
The structure of first stator and the 4th stator is identical, and the second stator is identical with the structure of third stator；Described
The both ends of one mover, the second mover and third mover pass through first connecting rod 17 respectively and the second connecting rod 18 is attached；The
One mover, the second mover and third mover include that two mover iron cores, multiple permanent magnets 9 and a magnetic barrier 16, magnetic barrier are located at
Between two mover iron cores, prevent both sides magnetic field from influencing each other.By changing the relative position of permanent magnet, generate each mover
End Slot force there are certain phase difference, cause the overall end Slot force generated minimum.Multiple permanent magnets are located at two
The outer wall of mover iron core.Gas length between mover and two stators is equal.
It is moved as shown in Fig. 2, two mover iron cores of the first mover are from top to bottom followed successively by the first mover iron core 10 and second
Two mover iron cores of sub- iron core 11, the second mover are from top to bottom followed successively by third mover iron core 12 and the 4th mover iron core 13,
Two mover iron cores of third mover are from top to bottom followed successively by the 5th mover iron core 14 and the 6th mover iron core 15,
The first mover iron core is identical as the permanent magnet arrangement on the 6th mover iron core outer wall, the first mover iron core and
Permanent magnet arrangement position on two mover iron core outer walls differs λ, the permanent magnetism on the second mover iron core and the 4th mover iron core outer wall
Body arrangement position differs λ, and the permanent magnet magnetization on the second mover iron core and third mover iron core outer wall is contrary, the 4th mover
Permanent magnet magnetization on iron core and the 5th mover iron core outer wall is contrary.λ=2m τp±2/3τp, wherein τpFor permanent magnet pole
Away from m is positive integer.
First stator, the second stator, third stator and the 4th stator include stator core and winding 8, to four stators
In three-phase windings replace, the three-phase windings axis of the first stator and the 4th stator is overlapped, the first stator, the second stator,
The three-phase windings axis of third stator is not overlapped mutually.A, B, C phase winding axis in second stator is respectively and in the first stator
B, C, A phase winding axis are overlapped, A, B, C phase winding axis in third stator respectively with C, A, B phase winding in the first stator
Axis is overlapped.It is handled by transposition, the back-emf phase that corresponding phase winding generates in four stators is identical.Again by four stators
In A phase winding A1, A2, A3, A4, A5, A6, A7 and A8 connect, B phase winding B1, B2, B3, B4, B5, B6, B7 and B8 into
Row series connection, C phase winding C1, C2, C3, C4, C5, C6, C7 and C8 connect.By replacing and connecting, three-phase windings are in space
On be distributed symmetrically, therefore symmetrical three opposite potential can be generated, further reduce force oscillation.
Three-phase windings are Circular Winding, single layer lap winding or the double-deck lap winding.Magnetic barrier material be non-magnet material such as aluminium,
The material of copper etc., the permanent magnet is neodymium iron boron, SmCo, alnico or ferrite, and the permanent magnet is on mover iron core
Mounting means be surface-mount type, it is embedded or alternately pole formula.The material of stator core and mover iron core is permeability magnetic material such as silicon steel sheet.
First mover, the direction of motion of the second mover and third mover and speed moment keep identical, the first mover, second
With the speed planning curvilinear motion of triangular wave or trapezoidal wave when mover and third mover work.Linear motor is applied to fracturing pump
When, the plunger that the mover of linear motor directly drives fracturing pump does linear reciprocating motion.
After the three-phase windings of stator are connected, which only has a set of three-phase windings, it is only necessary to a frequency converter
It powers to it.After being passed through three-phase current to motor, armature winding can form travelling-magnetic-field in air gap, the travelling-magnetic-field and
The magnetic field that permanent magnet is formed interacts to form thrust, can control electricity by the size and frequency that adjust output current of frequency converter
Machine thrust output and mover movement velocity.The speed of service and position that three movers need to be kept when operation are consistent, and pass through change
Frequency device controls mover with triangular wave or trapezoidal wave speed planning curvilinear motion, when the multiple linear motor units of guarantee can be with certain
Phase difference operation when to be able to achieve fracturing pump output flow uniform.
As it will be easily appreciated by one skilled in the art that the foregoing is merely illustrative of the preferred embodiments of the present invention, not to
The limitation present invention, any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should all include
Within protection scope of the present invention.
Claims (9)
1. a kind of fracturing pump directly drives with linear motor, which is characterized in that including the first stator (1), the first mover being arranged successively
(5), the second stator (2), the second mover (6), third stator (3), third mover (7) and the 4th stator (4),
First stator (1) is identical with the structure of the 4th stator (4), the structure phase of the second stator (2) and third stator (3)
Together；
The both ends of first mover (5), the second mover (6) and third mover (7) are attached by connecting rod respectively；First
Mover (5), the second mover (6) and third mover (7) include two mover iron cores, multiple permanent magnets and a magnetic barrier, magnetic barrier
Between two mover iron cores, multiple permanent magnets are located at the outer wall of two mover iron cores；
Two mover iron cores of first mover (5) are from top to bottom followed successively by the first mover iron core (10) and the second mover iron core
(11), two mover iron cores of the second mover (6) are from top to bottom followed successively by third mover iron core (12) and the 4th mover iron core
(13), two mover iron cores of third mover (7) are from top to bottom followed successively by the 5th mover iron core (14) and the 6th mover iron core
(15),
The first mover iron core (10) is identical as the permanent magnet arrangement on the 6th mover iron core (15) outer wall, the first mover iron core
(10) the permanent magnet arrangement position and on second mover iron core (11) outer wall differs λ, the second mover iron core (11) and the 4th mover
Permanent magnet arrangement position on iron core (13) outer wall differs λ, on the second mover iron core (11) and third mover iron core (12) outer wall
Permanent magnet magnetization it is contrary, the permanent magnet magnetization direction on the 4th mover iron core (13) and the 5th mover iron core (14) outer wall
On the contrary.
2. a kind of fracturing pump as described in claim 1 directly drives with linear motor, which is characterized in that λ=2m τp±2/3τp,
Wherein, τpIt is permanent magnet pole away from m is positive integer.
3. a kind of fracturing pump as claimed in claim 1 or 2 directly drives with linear motor, which is characterized in that first stator
(1), the second stator (2), third stator (3) and the 4th stator (4) include stator core and three-phase windings.
4. a kind of fracturing pump as claimed in claim 3, which directly drives, uses linear motor, which is characterized in that first stator (1) and
The three-phase windings axis of 4th stator (4) is overlapped.
5. a kind of fracturing pump as claimed in claim 3, which directly drives, uses linear motor, which is characterized in that first stator (1), the
Two stators (2), third stator (3) three-phase windings axis be not overlapped mutually.
6. a kind of fracturing pump as claimed in claim 3 directly drives with linear motor, which is characterized in that the three-phase windings are annular
Winding, single layer lap winding or the double-deck lap winding.
7. a kind of fracturing pump as claimed in claim 1 or 2 directly drives with linear motor, which is characterized in that the material of the magnetic barrier
Material for non-magnet material, the permanent magnet is neodymium iron boron, SmCo, alnico or ferrite, and the permanent magnet is in mover
Mounting means on iron core is surface-mount type, embedded or alternately pole formula.
8. a kind of fracturing pump as claimed in claim 1 or 2 directly drives with linear motor, which is characterized in that first mover
(5), the second mover (6) is identical with the direction of motion of third mover (7) and the holding of speed moment, the first mover (5), the second mover
(6) with the speed planning curvilinear motion of triangular wave or trapezoidal wave when and third mover (7) works.
9. a kind of fracturing pump as claimed in claim 1 or 2 directly drives with linear motor, which is characterized in that the linear motor is answered
When for fracturing pump, the plunger that the mover of linear motor directly drives fracturing pump does linear reciprocating motion.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810566403.0A CN108667246B (en) | 2018-06-05 | 2018-06-05 | A kind of fracturing pump, which directly drives, uses linear motor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810566403.0A CN108667246B (en) | 2018-06-05 | 2018-06-05 | A kind of fracturing pump, which directly drives, uses linear motor |
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| Publication Number | Publication Date |
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| CN108667246A CN108667246A (en) | 2018-10-16 |
| CN108667246B true CN108667246B (en) | 2019-08-30 |
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Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109361305A (en) * | 2018-12-12 | 2019-02-19 | 宋局 | A kind of structure of Dual-conjugate bar type linear motor |
| US20210044191A1 (en) * | 2019-08-07 | 2021-02-11 | Linear Labs, Inc. | Linear machine |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101401284A (en) * | 2006-03-22 | 2009-04-01 | 西门子公司 | Electrical machine, in particular a generator |
| CN101405931A (en) * | 2006-03-16 | 2009-04-08 | 爱丁堡大学董事会 | Generator and magnetic flux conducting unit |
| CN105305771A (en) * | 2015-11-17 | 2016-02-03 | 西安交通大学 | Transverse flux mutual inductance coupling linear switched reluctance motor |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100440389B1 (en) * | 2001-12-26 | 2004-07-14 | 한국전기연구원 | A 2-phase Transverse Flux Linear Motor With Permanent Magnet Excitation |
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- 2018-06-05 CN CN201810566403.0A patent/CN108667246B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101405931A (en) * | 2006-03-16 | 2009-04-08 | 爱丁堡大学董事会 | Generator and magnetic flux conducting unit |
| CN101401284A (en) * | 2006-03-22 | 2009-04-01 | 西门子公司 | Electrical machine, in particular a generator |
| CN105305771A (en) * | 2015-11-17 | 2016-02-03 | 西安交通大学 | Transverse flux mutual inductance coupling linear switched reluctance motor |
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