CN111181452A - Method for compensating permanent magnet excitation performance difference in batch production of permanent magnet motors - Google Patents
Method for compensating permanent magnet excitation performance difference in batch production of permanent magnet motors Download PDFInfo
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- CN111181452A CN111181452A CN202010110889.4A CN202010110889A CN111181452A CN 111181452 A CN111181452 A CN 111181452A CN 202010110889 A CN202010110889 A CN 202010110889A CN 111181452 A CN111181452 A CN 111181452A
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- 230000005284 excitation Effects 0.000 title claims abstract description 45
- 238000000034 method Methods 0.000 title claims abstract description 31
- 238000010923 batch production Methods 0.000 title claims abstract description 9
- 238000013461 design Methods 0.000 claims abstract description 41
- 230000001360 synchronised effect Effects 0.000 claims abstract description 30
- 238000004519 manufacturing process Methods 0.000 claims abstract description 13
- 238000012360 testing method Methods 0.000 claims description 19
- 238000004804 winding Methods 0.000 claims description 10
- 230000008901 benefit Effects 0.000 abstract description 3
- 230000008859 change Effects 0.000 description 3
- 230000014509 gene expression Effects 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000012271 agricultural production Methods 0.000 description 1
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- 238000012938 design process Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000005405 multipole Effects 0.000 description 1
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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
- H02P6/00—Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
- H02P6/14—Electronic commutators
- H02P6/16—Circuit arrangements for detecting position
- H02P6/18—Circuit arrangements for detecting position without separate position detecting elements
- H02P6/182—Circuit arrangements for detecting position without separate position detecting elements using back-emf in windings
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/34—Testing dynamo-electric machines
- G01R31/343—Testing dynamo-electric machines in operation
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- Permanent Magnet Type Synchronous Machine (AREA)
Abstract
The invention belongs to a performance compensation method for a permanent magnet motor, and particularly relates to a compensation method for permanent magnet excitation performance difference in batch production of the permanent magnet motor. Which comprises the following steps: step 1, determining a basic principle of the running performance of a permanent magnet synchronous motor according to induced electromotive force, and judging the difference of permanent magnet excitation performance; and 2, compensating the excitation performance difference of the permanent magnet, and determining a qualified product. The method ensures that the induced electromotive force is unchanged by adjusting the design parameters, thereby reducing the difference of the performance of the permanent magnet motor, even keeping the performance unchanged, reducing the product rejection rate of motor production enterprises and improving the economic benefit of the enterprises.
Description
Technical Field
The invention belongs to a performance compensation method for a permanent magnet motor, and particularly relates to a compensation method for permanent magnet excitation performance difference in batch production of the permanent magnet motor.
Background
The permanent magnet motor is widely applied to various fields of aerospace, national defense, industrial and agricultural production and daily life by virtue of the remarkable advantages of simple structure, reliable operation, small volume, light weight, small loss, high efficiency, flexible and various shapes and sizes of the motor and the like.
In the design and production process of the permanent magnet synchronous motor, stable and accurate performance parameters of the permanent magnet are important bases for ensuring the superior performance of the permanent magnet motor. However, the mass production of permanent magnet materials inevitably produces performance differences, which lead to performance differences of permanent magnet motors, thereby affecting the application of permanent magnet motors.
Disclosure of Invention
The invention aims to provide a method for compensating the excitation performance difference of permanent magnets in the batch production of permanent magnet motors, aiming at the problem of the performance of the permanent magnet motors caused by the excitation performance difference of the permanent magnets in the existing batch production.
In order to achieve the purpose, the invention adopts the following technical scheme, which comprises the following steps.
And 2, compensating the excitation performance difference of the permanent magnet, and determining a qualified product.
Further, in the step 1, the determination of the difference of the permanent magnet excitation performance of the permanent magnet synchronous motor is realized by measuring the no-load back electromotive force of the motor, the no-load back electromotive force is obtained by a back-dragging method or a minimum current method, and if the | test value-design value |/design value >5%, the difference of the permanent magnet excitation performance exists.
Furthermore, the back-dragging method is that a prime motor is used for dragging the tested motor, the generator does no-load operation under the synchronous speed, three line voltages at the output end of the tested machine are measured, and the average value is the no-load back electromotive force; the prime motor can be selected from a three-phase synchronous motor with the same number of poles and the same power, or a three-phase asynchronous motor with the same number of poles and the same frequency, and the frequency of the three-phase asynchronous motor is adjusted to reach the synchronous rotating speed of the three-phase permanent magnet synchronous motor during the test; synchronous machines or asynchronous machines with different pole numbers and different frequencies can also be used, but the synchronous rotating speed of the tested machine is ensured.
Furthermore, the minimum current method is that the tested machine runs in no-load mode under the rated voltage and the rated frequency until the mechanical loss is stable, and the external voltage is adjusted to ensure that the no-load current reaches the minimum; wherein, the average value of the external end voltage is the no-load back electromotive force of the permanent magnet synchronous motor.
Further, in the step 2, the difference compensation of the permanent magnet excitation performance is realized by adjusting the number of turns of each phase of the motor winding in series and the size of the wire diameter, and the actual no-load back electromotive force is close to the design value under the condition that the full rate of the slots does not exceed the limit value.
Furthermore, if the no-load back electromotive force of the compensated motor is close to the design value, namely | the test value-the design value |/the design value is less than 2%, the motor is determined to be a factory-qualified product.
Furthermore, in step 2, when the no-load back electromotive force test value of the motor is lower than the design value, the actual remanence density of the permanent magnet is lower than the nominal valueB r(ii) a In order to compensate the over-low magnetic performance and improve the motor operability, the electric load of the motor needs to be increased, namely the number of turns of each phase of winding of the motor in series is increased; in order to ensure that the groove filling rate is unchanged compared with the original design, the wire diameter of the enameled wire should be reduced while the number of turns is increased.
When the no-load back electromotive force test value of the motor is higher than the design value, the number of turns of each phase of winding of the motor in series connection is reduced, the wire diameter of the enameled wire is increased, and the fact that the no-load back electromotive force is close to the design value as far as possible is guaranteed.
Compared with the prior art, the invention has the beneficial effects.
The invention provides a compensation method for permanent magnet excitation performance difference in permanent magnet motor batch production, which fully considers that when the performance parameters of the permanent magnets produced in batch are greatly changed, the induced electromotive force is ensured to be unchanged by adjusting design parameters, thereby reducing the performance difference of the permanent magnet motor, even keeping the performance unchanged, reducing the product rejection rate of motor production enterprises and improving the economic benefit of the enterprises.
Drawings
The invention is further described with reference to the following figures and detailed description. The scope of the invention is not limited to the following expressions.
Fig. 1 is a schematic flow chart of a method for compensating for differences in excitation performance of permanent magnets in mass production of permanent magnet motors.
Fig. 2 is a schematic diagram of the determination of motor performance by no-load back emf.
Fig. 3 is a comparison graph of no-load back emf.
Fig. 4 is a comparison of efficiency and power factor before and after motor compensation.
Detailed Description
As shown in fig. 1, the present invention includes.
1. And (5) judging the difference of the excitation performance of the permanent magnet.
Remanence of magnetismB rIs an important index for expressing the performance of the permanent magnet material, and the difference of the excitation performance of the permanent magnet is most obviously expressed on the remanence. The difference in excitation performance of the permanent magnet can be equivalent to a change in remanence over a range. The running performance of the permanent magnet synchronous motor is directly related to the performance of the permanent magnet, and the influence of the residual magnetic density on the performance is reflected by the induced electromotive force.
The relationship between the induced electromotive force and the residual magnetic density of the permanent magnet synchronous motor is.
The difference of the residual magnetic density, namely the difference of the excitation performance of the permanent magnet, can be reflected by measuring the no-load back electromotive force of the permanent magnet synchronous motor.
And comparing the test value of the no-load back electromotive force with the design value, and if the absolute test value-design value/design value is greater than 5%, the difference of the permanent magnet excitation performance is proved to exist, the motor performance is influenced, the factory requirement is not met, and the difference of the permanent magnet performance needs to be compensated.
The measurement was carried out by the back-pull method. During testing, the tested motor is mechanically connected by the prime mover. The prime motor drives the tested motor to operate as a generator in no-load mode at the synchronous speed. Respectively measuring the voltage of the outlet terminal of the tested motorU ab，U bcAndU bcand taking the average value as the no-load back electromotive force line voltage value, and recording the temperature of the stator core of the motor and the ambient temperature at the moment.
Comparing the test value of the no-load back electromotive force with the design value, if the | test value-design value | is greater than 5%, the difference of the permanent magnet excitation performance is shown, and the principle of judging the permanent magnet excitation performance and the motor performance through the no-load back electromotive force is as follows:
the expression of the alternating-axis current and the direct-axis current of the permanent magnet synchronous motor is as follows:
the electromagnetic power expression of the permanent magnet synchronous motor is as follows:
assuming that the permanent magnet remanence is lower than the nominal value, no-load back electromotive force is generated according to the formula (1)E 0And when the power angle theta is reduced, the power angle theta is increased due to the reduction of the no-load back electromotive force through the formula (4), and then according to the formula (3), the direct-axis current is increased along with the increase of the power angleI dReduced, quadrature-axis currentI qAnd the stator current is increased because the quadrature-axis current amplitude is far larger than the direct-axis current, so that the copper loss and the stray loss are increased, and the total loss is increased although the iron loss is reduced, so that the efficiency is reduced.
2. And compensating the difference of the excitation performance of the permanent magnet.
When the no-load back electromotive force test value of the permanent magnet synchronous motor is different from the design value, the difference of the excitation performance of the permanent magnet is shown, and the difference of the excitation performance of the permanent magnet influences the performance of the permanent magnet synchronous motor, so the difference of the excitation performance of the permanent magnet needs to be compensated.
The method determines the performance principle of the permanent magnet motor based on the induced electromotive force of the permanent magnet motor, ensures that the induced electromotive force of the permanent magnet excitation performance difference motor is consistent with a design value by adjusting conveniently-changed electromagnetic design parameters, and realizes effective compensation of permanent magnet excitation performance difference.
When the no-load back electromotive force test value determined in the step 1 is lower than the design value, the actual residual magnetic density of the permanent magnet is lower than the nominal valueB r. In order to compensate lower magnetic performance and improve the running performance of the motor, the electric load of the motor is increased, namely the number of turns of each phase of winding of the motor in series is increased, the wire diameter of an enameled wire is reduced, and the no-load counter electromotive force measured in real time of the motor is enabled to be close to the design value as much as possible under the condition that the full factor of the motor is not changed. When the no-load back electromotive force test value of the motor is higher than the design value, the number of turns of each phase of winding of the motor in series connection is reduced, the wire diameter of the enameled wire is increased, and the compensated no-load back electromotive force is ensured to be close to the design value.
The compensation principle is as shown in figure 2, assuming that the residual magnetic density of the permanent magnet is lower than the rated nominal value, the no-load back electromotive force value is lower than the design value, increasing the number of turns of the winding to make the no-load back electromotive force value close to the design value, and simultaneously reducing the wire diameter to ensure that the full rate of the slot is not changed, thereby compensating the excitation performance difference. Assuming that the compensated no-load counter electromotive force is consistent with the design value, the stator resistance is increased due to the reduction of the wire diameter, the copper consumption is slightly increased, but the stator current is reduced, and the quadrature axis reactance and the direct axis reactance are correspondingly increased due to the increase of the number of turns, so that the power angle is increased, and the power factor is increased.
3. Determination of synthetic products
And (3) according to the no-load back electromotive force of the motor compensated in the step (2), if the test value-design value/design value is less than 2%, determining that the motor is a qualified product and allowing the motor to leave a factory for sale.
step 2, changing value delta of each phase of series turnsNThe value-taking principle is that the compensated no-load back electromotive force approaches the design value according to the formula (1), namelyE 0 (N+ or- △N) Is approximately equal toE 0 (design) in the formulaE 0 In order to be a no-load back electromotive force,Nfor each phase winding the number of turns in series, deltaNThe value of the change in the number of turns in series for each phase.
The principle of the change value of the wire diameter of the enameled wire in the step 2.1 and the step 2.2 is that the groove filling rate in the formula (2) is satisfiedS fAnd is not changed.
Fig. 4 is a data diagram of a compensation result of a 1.5kW permanent magnet synchronous motor based on a compensation method for a difference in permanent magnet excitation performance in mass production of permanent magnet motors, and when the compensation method for a difference in permanent magnet excitation performance in mass production of permanent magnet motors is adopted, the phase current of the motor is reduced and the efficiency of the motor is obviously improved when the motor outputs different powers. The compensation method for the excitation performance difference of the permanent magnet in the batch production of the permanent magnet motor can improve the performance reduction of the motor caused by the excitation performance difference of the permanent magnet.
The permanent magnet synchronous motor in the above embodiment is a 1.5kW three-phase motor, but is also suitable for other power classes of multiphase multipole case, including permanent magnet generator.
It should be understood that the detailed description of the present invention is only for illustrating the present invention and is not limited by the technical solutions described in the embodiments of the present invention, and those skilled in the art should understand that the present invention can be modified or substituted equally to achieve the same technical effects; as long as the use requirements are met, the method is within the protection scope of the invention.
Claims (7)
1. A compensation method for permanent magnet excitation performance difference in permanent magnet motor batch production is characterized by comprising the following steps:
step 1, determining a basic principle of the running performance of a permanent magnet synchronous motor according to induced electromotive force, and judging the difference of permanent magnet excitation performance;
and 2, compensating the excitation performance difference of the permanent magnet, and determining a qualified product.
2. The method for compensating for the difference in excitation performance of permanent magnets in mass production of permanent magnet motors according to claim 1, wherein: in the step 1, the judgment of the permanent magnet excitation performance difference of the permanent magnet synchronous motor is realized by measuring the no-load back electromotive force of the motor, the no-load back electromotive force is obtained by a back-dragging method or a minimum current method, and if the | test value-design value |/design value >5%, the difference of the permanent magnet excitation performance exists.
3. The method for compensating for the difference in excitation performance of permanent magnets in mass production of permanent magnet motors according to claim 2, wherein: the back-dragging method is that a prime motor is used for dragging a tested motor, the tested motor is used as a generator to run in a no-load mode at a synchronous rotating speed, three line voltages at the output end of the tested motor are measured, and the average value of the three line voltages is the no-load back electromotive force; the prime motor can be selected from a three-phase synchronous motor with the same number of poles and the same power, or a three-phase asynchronous motor with the same number of poles and the same frequency, and the frequency of the three-phase asynchronous motor is adjusted to reach the synchronous rotating speed of the three-phase permanent magnet synchronous motor during the test; synchronous machines or asynchronous machines with different pole numbers and different frequencies can also be used, but the synchronous rotating speed of the tested machine is ensured.
4. The method for compensating for the difference in excitation performance of permanent magnets in mass production of permanent magnet motors according to claim 2, wherein: the minimum current method is that the tested machine runs under the rated voltage and the rated frequency in no-load mode until the mechanical loss is stable, and the external voltage is adjusted to ensure that the no-load current reaches the minimum; wherein, the average value of the external end voltage is the no-load back electromotive force of the permanent magnet synchronous motor.
5. The method for compensating for the difference in excitation performance of permanent magnets in mass production of permanent magnet motors according to claim 1, wherein: in the step 2, the difference compensation of the permanent magnet excitation performance is realized by adjusting the number of turns of each phase of the motor winding in series and the size of the wire diameter, and the actual no-load back electromotive force is close to the design value under the condition that the full rate of the slot does not exceed the limit value.
6. The method for compensating for the difference in excitation performance of permanent magnets in mass production of permanent magnet motors according to claim 5, wherein: and if the no-load back electromotive force of the compensated motor is close to the design value, namely the testing value-the design value/the design value is less than 2%, determining that the motor is a factory-qualified product.
7. The method for compensating for the difference in excitation performance of permanent magnets in mass production of permanent magnet motors according to claim 5, wherein: in the step 2, when the no-load back electromotive force test value of the motor is lower than the design value, the fact that the actual remanence density of the permanent magnet is lower than the nominal value is shownB r(ii) a In order to compensate the over-low magnetic performance and improve the motor operability, the electric load of the motor needs to be increased, namely the number of turns of each phase of winding of the motor in series is increased; in order to ensure that the groove filling rate is unchanged compared with the original design, the wire diameter of the enameled wire is reduced while the number of turns is increased;
when the no-load back electromotive force test value of the motor is higher than the design value, the number of turns of each phase of winding of the motor in series connection is reduced, the wire diameter of the enameled wire is increased, and the fact that the no-load back electromotive force is close to the design value as far as possible is guaranteed.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114172418A (en) * | 2021-11-30 | 2022-03-11 | 中国第一汽车股份有限公司 | Motor current sensor state detection system and method |
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|---|---|---|---|---|
| CN102439823A (en) * | 2009-01-14 | 2012-05-02 | 罗伯特·博世有限公司 | Remanence tolerance compensation for electric machine |
| CN104184293A (en) * | 2014-07-16 | 2014-12-03 | 赵晓东 | Adjusting-type pole-changing speed-changing permanent-magnet synchronous motor |
| CN104734389A (en) * | 2013-12-20 | 2015-06-24 | 湖北海山科技有限公司上海分公司 | Stator disk and axial flux permanent magnet kinetic energy device |
| CN105717451A (en) * | 2016-01-22 | 2016-06-29 | 刘玉臻 | Pumping unit and method and device for measuring no-load counter electromotive force of permanent magnet motor of pumping unit |
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- 2020-02-24 CN CN202010110889.4A patent/CN111181452B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102439823A (en) * | 2009-01-14 | 2012-05-02 | 罗伯特·博世有限公司 | Remanence tolerance compensation for electric machine |
| CN104734389A (en) * | 2013-12-20 | 2015-06-24 | 湖北海山科技有限公司上海分公司 | Stator disk and axial flux permanent magnet kinetic energy device |
| CN104184293A (en) * | 2014-07-16 | 2014-12-03 | 赵晓东 | Adjusting-type pole-changing speed-changing permanent-magnet synchronous motor |
| CN105717451A (en) * | 2016-01-22 | 2016-06-29 | 刘玉臻 | Pumping unit and method and device for measuring no-load counter electromotive force of permanent magnet motor of pumping unit |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114172418A (en) * | 2021-11-30 | 2022-03-11 | 中国第一汽车股份有限公司 | Motor current sensor state detection system and method |
| CN114172418B (en) * | 2021-11-30 | 2024-03-15 | 中国第一汽车股份有限公司 | Motor current sensor state detection system and method |
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