CN111224596A - Permanent magnet synchronous motor dragging device improved by induction motor - Google Patents
Permanent magnet synchronous motor dragging device improved by induction motor Download PDFInfo
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- CN111224596A CN111224596A CN202010022566.XA CN202010022566A CN111224596A CN 111224596 A CN111224596 A CN 111224596A CN 202010022566 A CN202010022566 A CN 202010022566A CN 111224596 A CN111224596 A CN 111224596A
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- permanent magnet
- variable frequency
- magnet synchronous
- rotor
- motor
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
- H02P21/14—Estimation or adaptation of machine parameters, e.g. flux, current or voltage
- H02P21/141—Flux estimation
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/12—Methods or apparatus for controlling the flow of the obtained fluid to or in wells
- E21B43/121—Lifting well fluids
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
- H02P21/0003—Control strategies in general, e.g. linear type, e.g. P, PI, PID, using robust control
- H02P21/0017—Model reference adaptation, e.g. MRAS or MRAC, useful for control or parameter estimation
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
- H02P21/22—Current control, e.g. using a current control loop
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P25/00—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details
- H02P25/02—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the kind of motor
- H02P25/022—Synchronous motors
- H02P25/024—Synchronous motors controlled by supply frequency
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P27/00—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage
- H02P27/04—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage
- H02P27/06—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters
- H02P27/08—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters with pulse width modulation
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Control Of Ac Motors In General (AREA)
Abstract
The invention relates to a pumping unit driving system, in particular to a dragging device for a permanent magnet synchronous motor transformed by an induction motor. The device includes: the system comprises a variable frequency control box, a bus braking unit and a permanent magnet synchronous motor; a high-precision vector variable frequency controller, a large-current alternating current contactor, a brake switching unit and an air switch are respectively fixed in the variable frequency control box, and a bus brake unit is fixed on the back of the variable frequency control box; the bus braking unit comprises a star-shaped or triangular connected corrugated resistor, and the permanent magnet synchronous motor comprises a stator and a rotor; the stator iron core is formed by laminating silicon steel sheets with high magnetic permeability; the stator is uniformly provided with a groove and embedded with a stator winding, the rotor is formed by casting or punching lamination, and the rotor is of a built-in or surface-mounted magnetic pole structure; at least 4 iron core slots are arranged under each pair of magnetic poles. The dragging device for the transformed permanent magnet synchronous motor of the induction motor provided by the invention realizes the effects of improving the efficiency and the power factor, reducing the impact on a power grid and saving electric energy.
Description
Technical Field
The invention relates to a pumping unit driving system, in particular to a dragging device for a permanent magnet synchronous motor transformed by an induction motor.
Background
At present, in the production operation of an oil field, the traditional asynchronous motor and the driving motors of various types of oil pumping devices have the defects of complex mechanical structure, large motor size, low material utilization rate, low overall system efficiency and the like. Especially, the wells and mines are often inconsistent in different working intervals of different oil wells, the traditional driving mode cannot adjust the high-precision rotating speed of the driving motor, and only the belt pulleys with different sizes can be continuously replaced to change the transmission ratio and adjust the speed, so that the manual labor is greatly increased, the stability of oil extraction in the oil field is influenced, and the requirements of long-time and automatic oil extraction are not facilitated. Meanwhile, most of the existing permanent magnet motor speed regulation systems use a variable-voltage variable-frequency speed regulation strategy, although the strategy has the advantages of low cost, simplicity in use and the like, the control strategy can reduce the moment when the motor is at low speed due to the unique working characteristics of the beam pumping unit, and compensation is difficult to realize under different well conditions.
Disclosure of Invention
Technical problem to be solved
The invention provides a dragging device for reforming a permanent magnet synchronous motor by an induction motor, which aims to overcome the defects that the working efficiency is low and the like because the torque is low and the requirements of different working conditions cannot be met in the prior art.
(II) technical scheme
In order to solve the above problems, the present invention provides a dragging device for transforming an induction motor into a permanent magnet synchronous motor, comprising: the system comprises a variable frequency control box, a bus braking unit and a permanent magnet synchronous motor; a high-precision vector variable frequency controller, a large-current alternating current contactor, a brake switching unit and an air switch are respectively fixed in the variable frequency control box, and a bus brake unit is fixed on the back of the variable frequency control box;
the high-current alternating current contactor is arranged in front of a circuit of the high-precision vector variable frequency controller and is connected with the high-precision vector variable frequency controller;
the high-precision vector frequency converter accurately controls the permanent magnet synchronous motor;
the bus braking unit comprises a star-shaped or triangular connected corrugated resistor and is connected with the high-precision vector frequency converter through the braking switching unit; the brake switching unit is used for switching the working state of the motor;
the permanent magnet synchronous motor comprises a stator and a rotor; the gap between the stator and the rotor is 0.5-2mm as an energy conversion path;
the stator iron core is formed by laminating silicon steel sheets with high magnetic permeability; stator windings are uniformly embedded in the stator, and the number of the slots is even;
the rotor is formed by laminating castings or punching sheets, and is of a built-in or surface-mounted magnetic pole structure; at least 4 iron core slots are arranged below each pair of magnetic poles;
a plurality of uniformly distributed magnetic steel grooves are formed in the rotor, and axial baffles are arranged at two ends of the rotor;
and epoxy resin is filled in the gap between the magnetic steel groove and the magnetic steel.
Preferably, the variable frequency control box body is made of steel and is sprayed with anti-rust paint.
(III) advantageous effects
The invention provides a dragging device for a permanent magnet synchronous motor transformed from an induction motor, which adopts a permanent magnet motor dragging device driven by a high-precision vector frequency converter to replace the original dragging device, adopts a sensorless vector frequency conversion control technology to realize high-performance control aiming at oil extraction systems under different wells and mines, adopts a high-performance permanent magnet motor to replace an asynchronous motor and the like, and realizes the effects of improving the efficiency and the power factor, reducing the impact on a power grid and saving electric energy.
Drawings
FIG. 1 is a schematic structural diagram of a modified PMSM (permanent magnet synchronous motor) dragging device for an induction motor according to an embodiment of the present invention;
fig. 2 is a control principle structure diagram of a high-precision vector variable frequency controller in a traction device of a permanent magnet synchronous motor modified by an induction motor according to an embodiment of the invention.
Wherein: 1. the system comprises a power transformer, 2, a high-precision vector variable frequency controller and 3, a permanent magnet synchronous motor.
Detailed Description
The present invention will be described in detail below with reference to the drawings and examples.
As shown in fig. 1 and 2, the present invention provides a driving device for transforming a permanent magnet synchronous motor into an induction motor, comprising:
the system comprises a variable frequency control box, a bus braking unit and a permanent magnet synchronous motor 3; the high-precision vector variable frequency controller 2, the heavy-current alternating current contactor, the brake switching unit and the air switch are respectively fixed in the variable frequency control box body, and the bus brake unit is fixed on the back of the variable frequency control box body; and the large-current alternating-current contactor is arranged in front of the circuit of the high-precision vector variable-frequency controller and is connected with the high-precision vector variable-frequency controller.
The frequency conversion control box is made of steel and sprayed with antirust paint, and has the characteristics of corrosion resistance, water resistance and impact resistance.
The high-precision vector frequency converter accurately controls the permanent magnet synchronous motor; the high-precision vector frequency conversion controller 2 is connected with a power transformer 1.
The high-precision vector frequency converter can accurately control the driving motor by adopting different control modes and parameters. The high-precision vector frequency converter is an integrated high-precision device, can ensure that the permanent magnet motor has good performance under wide rotating speed by adjusting control parameters, and realizes the vector control of the motor through an internal PI adaptive algorithm.
The invention adopts the sensorless high-precision vector variable frequency controller as the power supply of the driving device, does not need to add a position sensor in the motor, saves the volume and the cost of the part, measures an accurate motor mathematical model by self-learning and self-setting aiming at the motors with different power grades, and obtains the flux linkage position and the current time phase of the motor through the PI self-adaptive controller algorithm so as to accurately control the motor. On the basis, when the well condition has a problem, a protection measure is taken for the motor to prevent the motor from being burnt out and braking in time. The control precision of the system is improved, the corresponding driving permanent magnet motor can be designed into multiple poles, so that the operating frequency of the motor is wide, the motor operates stably at low speed and has small vibration, meanwhile, the overload capacity of the motor is improved by the frequency converter, the waste of materials can be reduced in the control angle, and the comprehensive performance of the driving device is improved.
As shown in fig. 2, a block diagram of a control portion of the high-precision vector frequency conversion controller apparatus of the present invention is shown, and the present invention adopts a vector control mode, and the principle thereof is as follows: the stator current vector is decomposed into the exciting current and the torque current according to Clark-Park vector transformation by measuring and controlling the stator current vector of the permanent magnet motor, the amplitude and the phase of the two components are respectively controlled, the magnetic flux of the permanent magnet motor is provided by a permanent magnet, so that the exciting component of the stator current can be controlled to be zero, and all energy is output as the torque component, namely the optimal utilization of electric energy is realized. In the frequency converter, an exciting current component is required to be set firstly, a torque component is calculated according to required torque, and then equivalent three-phase current amplitude and phase are obtained through operation, so that the motor is accurately controlled.
The invention adopts a sensorless vector control method, and adopts a PI self-adaptive controller method without the traditional position sensor for detecting the position of the motor rotor. The method is essentially based on a control method of a mathematical model, and has good dynamic property and robustness by continuously adjusting the internal parameters of the correction motor during self-learning to adapt to the dynamic characteristics of a control object and disturbance.
The bus braking unit comprises a star-shaped or triangular connected corrugated resistor and is connected with the high-precision vector frequency converter through the braking switching unit; the brake switching unit is used for switching the working state of the motor; the bus braking unit solves the problem that the bus direct-current voltage is overlarge due to braking power generation when the sucker rod of the pumping unit downstroke, and protects the motor and the frequency converter. And the resistance of the bus braking unit is determined by the high-precision vector frequency converter of the corresponding model and the braking rate.
The permanent magnet synchronous motor comprises a stator and a rotor; the gap between the stator and the rotor is 1.5mm as an energy conversion path;
the stator iron core is formed by laminating high-permeability silicon steel sheets to reduce eddy current loss, grooves are uniformly formed in the silicon steel sheets, and double-layer windings are distributed in the grooves and are electrified with three-phase symmetrical alternating current to excite circular rotating magnetic potential.
The rotor is formed by laminating castings or punching sheets, and is of a built-in or surface-mounted magnetic pole structure; at least 4 iron core slots are arranged below each pair of magnetic poles; the rotor is designed into a multi-pole structure to enable the rotating speed of the motor to work in a reasonable range, the rotor adopts a built-in structure, the strength of the motor rotor can be enhanced, the heating of magnetic steel is reduced, the possibility of demagnetization is further reduced, and the stability of the motor is improved.
A plurality of uniformly distributed magnetic steel grooves are formed in the rotor, and axial baffles are arranged at two ends of the rotor. The rotor design of this kind of structure has improved the assembly quality and has strengthened rotor mechanical strength, can deal with the higher rotational speed's of this series of permanent-magnet machine characteristic, has avoided simultaneously because the bearing warp and arouse that the motor "sweeps the thorax". On the basis, axial baffles are additionally arranged at the two ends of the rotor to prevent the axis of the magnetic steel from moving, epoxy resin is filled in the gap between the rotor slot and the magnetic steel, and the radial and tangential movement of the magnetic steel is prevented.
The permanent magnet synchronous motor improves the performance of the motor and saves the production cost, the stator is formed by laminating high-permeability silicon steel sheets to reduce the eddy current loss, the silicon steel sheets are uniformly grooved, and double-layer windings which are electrified with three-phase symmetrical alternating current are distributed in the grooves to excite the circular rotating magnetic potential; the rotor can be designed into a multi-pole structure to enable the rotating speed of the motor to work in a reasonable range, the rotor adopts a built-in structure, the strength of the motor rotor can be enhanced, the heating of magnetic steel is reduced, the possibility of demagnetization is further reduced, and the stability of the motor is improved.
The high-precision vector frequency conversion controller is connected with the permanent magnet synchronous motor through a three-phase power cable, a bus brake unit is added in combination with the working condition of an oil field to balance electric energy to protect the motor, and meanwhile, the frequency converter intelligently switches working states in combination with the working condition characteristics of the pumping unit to reduce impact on a power grid. The permanent magnet motor used by the invention is formed by modifying an induction motor, has higher efficiency and power factor, and the adoption of the permanent magnet synchronous motor dragging device of the invention to replace the existing induction motor driving device can obviously reduce the impact of a pumping unit system on a power grid according to experiments, save more than twenty percent of electricity for an oil field every year and greatly improve the oil extraction efficiency and stability.
The invention provides a dragging device for reforming a permanent magnet synchronous motor of an induction motor, which adopts a high-precision vector variable frequency controller to control the permanent magnet synchronous motor to replace the traditional motor such as an asynchronous motor and the like which is directly powered by a power grid. When reducing power consumption and reducing the impact on the power grid, the working efficiency of the whole oil pumping unit is improved, the human input is reduced, and the operation stability of different oil extraction working conditions is effectively improved.
The above embodiments are only for illustrating the invention and are not to be construed as limiting the invention, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention, therefore, all equivalent technical solutions also belong to the scope of the invention, and the scope of the invention is defined by the claims.
Claims (2)
1. The utility model provides an induction machine reforms transform PMSM drive arrangement which characterized in that includes: the system comprises a variable frequency control box, a bus braking unit and a permanent magnet synchronous motor; a high-precision vector variable frequency controller, a large-current alternating current contactor, a brake switching unit and an air switch are respectively fixed in the variable frequency control box, and a bus brake unit is fixed on the back of the variable frequency control box;
the high-current alternating current contactor is arranged in front of a circuit of the high-precision vector variable frequency controller and is connected with the high-precision vector variable frequency controller;
the high-precision vector frequency conversion controller is connected with the permanent magnet synchronous motor by a three-phase power cable;
the high-precision vector frequency converter accurately controls the permanent magnet synchronous motor;
the bus braking unit comprises a star-shaped or triangular connected corrugated resistor and is connected with the high-precision vector frequency converter through the braking switching unit; the brake switching unit is used for switching the working state of the motor;
the permanent magnet synchronous motor comprises a stator and a rotor; the gap between the stator and the rotor is 0.5-2mm as an energy conversion path;
the stator iron core is formed by laminating silicon steel sheets with high magnetic permeability; stator windings are uniformly embedded in the stator, and the number of the slots is even;
the rotor is formed by laminating castings or punching sheets, and is of a built-in or surface-mounted magnetic pole structure; at least 4 iron core slots are arranged below each pair of magnetic poles;
a plurality of uniformly distributed magnetic steel grooves are formed in the rotor, and axial baffles are arranged at two ends of the rotor;
and epoxy resin is filled in the gap between the magnetic steel groove and the magnetic steel.
2. The improved PMSM dragging device of claim 1, wherein the variable frequency control box is made of steel and is sprayed with anti-rust paint.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010022566.XA CN111224596A (en) | 2020-01-09 | 2020-01-09 | Permanent magnet synchronous motor dragging device improved by induction motor |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010022566.XA CN111224596A (en) | 2020-01-09 | 2020-01-09 | Permanent magnet synchronous motor dragging device improved by induction motor |
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| CN111224596A true CN111224596A (en) | 2020-06-02 |
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| CN202010022566.XA Pending CN111224596A (en) | 2020-01-09 | 2020-01-09 | Permanent magnet synchronous motor dragging device improved by induction motor |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111756305A (en) * | 2020-06-21 | 2020-10-09 | 中车永济电机有限公司 | Locomotive auxiliary converter topological structure |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008092781A (en) * | 2006-09-30 | 2008-04-17 | C & S Kokusai Kenkyusho:Kk | Drive control method for permanent magnet synchronous motor |
| CN202103624U (en) * | 2011-05-19 | 2012-01-04 | 杭州赛翔科技有限公司 | Oil field servo control system |
| CN203377832U (en) * | 2013-06-07 | 2014-01-01 | 浙江西子富沃德电机有限公司 | Drive control device of oil field screw pump motor |
| CN104052208A (en) * | 2014-06-20 | 2014-09-17 | 王贤长 | Method for transforming three-phase asynchronous motor into permanent magnet motor |
| CN205195608U (en) * | 2015-11-27 | 2016-04-27 | 刘松岭 | Beam -pumping unit adjusting device and beam -pumping unit that cooperation device used thereof |
| CN110611463A (en) * | 2019-07-18 | 2019-12-24 | 江苏理工学院 | Speed regulating system of permanent magnet synchronous electric spindle and control method thereof |
-
2020
- 2020-01-09 CN CN202010022566.XA patent/CN111224596A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008092781A (en) * | 2006-09-30 | 2008-04-17 | C & S Kokusai Kenkyusho:Kk | Drive control method for permanent magnet synchronous motor |
| CN202103624U (en) * | 2011-05-19 | 2012-01-04 | 杭州赛翔科技有限公司 | Oil field servo control system |
| CN203377832U (en) * | 2013-06-07 | 2014-01-01 | 浙江西子富沃德电机有限公司 | Drive control device of oil field screw pump motor |
| CN104052208A (en) * | 2014-06-20 | 2014-09-17 | 王贤长 | Method for transforming three-phase asynchronous motor into permanent magnet motor |
| CN205195608U (en) * | 2015-11-27 | 2016-04-27 | 刘松岭 | Beam -pumping unit adjusting device and beam -pumping unit that cooperation device used thereof |
| CN110611463A (en) * | 2019-07-18 | 2019-12-24 | 江苏理工学院 | Speed regulating system of permanent magnet synchronous electric spindle and control method thereof |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111756305A (en) * | 2020-06-21 | 2020-10-09 | 中车永济电机有限公司 | Locomotive auxiliary converter topological structure |
| CN111756305B (en) * | 2020-06-21 | 2022-06-14 | 中车永济电机有限公司 | Locomotive auxiliary converter topological structure |
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Application publication date: 20200602 |