CN113765244A - Design method of three-phase motor stator - Google Patents
Design method of three-phase motor stator Download PDFInfo
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- CN113765244A CN113765244A CN202111165233.3A CN202111165233A CN113765244A CN 113765244 A CN113765244 A CN 113765244A CN 202111165233 A CN202111165233 A CN 202111165233A CN 113765244 A CN113765244 A CN 113765244A
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- 238000000034 method Methods 0.000 title claims abstract description 15
- 238000004804 winding Methods 0.000 claims abstract description 94
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 7
- 230000004907 flux Effects 0.000 claims description 4
- 238000006243 chemical reaction Methods 0.000 claims 1
- 229910052742 iron Inorganic materials 0.000 claims 1
- 238000004080 punching Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 2
- RFHAOTPXVQNOHP-UHFFFAOYSA-N fluconazole Chemical compound C1=NC=NN1CC(C=1C(=CC(F)=CC=1)F)(O)CN1C=NC=N1 RFHAOTPXVQNOHP-UHFFFAOYSA-N 0.000 description 2
- 238000003475 lamination Methods 0.000 description 2
- 230000008094 contradictory effect Effects 0.000 description 1
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K1/00—Details of the magnetic circuit
- H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
- H02K1/12—Stationary parts of the magnetic circuit
- H02K1/16—Stator cores with slots for windings
- H02K1/165—Shape, form or location of the slots
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K3/00—Details of windings
- H02K3/04—Windings characterised by the conductor shape, form or construction, e.g. with bar conductors
- H02K3/12—Windings characterised by the conductor shape, form or construction, e.g. with bar conductors arranged in slots
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K3/00—Details of windings
- H02K3/04—Windings characterised by the conductor shape, form or construction, e.g. with bar conductors
- H02K3/28—Layout of windings or of connections between windings
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K2213/00—Specific aspects, not otherwise provided for and not covered by codes H02K2201/00 - H02K2211/00
- H02K2213/03—Machines characterised by numerical values, ranges, mathematical expressions or similar information
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Windings For Motors And Generators (AREA)
Abstract
The application provides a design method of a three-phase motor stator, namely a stator core and a stator winding of the three-phase motor are designed according to the basic rule of three-phase alternating current. The method comprises the following steps: determining the number Z of slots of the stator core, and determining the number q of slots occupied by each pole and each phase of the stator windingAccount forNumber of overlapping grooves q on one side thereofStackCalculating the space electrical angle from each slot in each phase winding of each pole to the center of the magnetic pole and the corresponding sine value qsinAccording to the sine value qsinAnd calculating the number of turns of the winding in each slot and the corresponding slot area, and properly adjusting the number of turns of the winding in the overlapped slots and the slot area. Because the stator core and the stator winding of the three-phase motor are designed according to the basic rule of three-phase alternating current, the waveform of the magnetomotive force generated by the three-phase winding of the motor is basically a sine wave, and the waveform of the magnetomotive force is a sine waveThe roundness of the synthesized rotating magnetic field is better, thereby reducing the loss and the cost of the motor and improving the comprehensive performances of torque, vibration and the like.
Description
Technical Field
The application relates to the technical field of three-phase motors, in particular to a design method of a three-phase motor stator, which comprises the following steps: according to the basic rule of three-phase alternating current, a stator core and a stator winding of the three-phase motor are designed.
Background
In the prior art, the stator of a three-phase motor is designed, and an iron core of the three-phase motor is provided with a plurality of uniformly distributed grooves, and the shapes and the areas of the grooves are the same. The iron core is provided with stator teeth and a stator yoke which are used for magnetic conduction besides a groove, and the space sizes of the groove, the teeth and the yoke have a certain proportion. The three-phase magnetomotive force generated by the three-phase windings is independent and related to each other and combined into a circular rotating magnetic field, and the electric energy is converted into mechanical energy through the rotating magnetic field. In order to make the waveform of magnetomotive force generated by a three-phase winding as close to a sine wave as possible (under the same condition, the standard sine waveform can minimize the loss of a motor, minimize the cost and make the best comprehensive performance such as torque vibration and the like), some improvements are made on the three-phase winding, and a plurality of different windings are designed, such as: double-layer windings, single-double-layer windings, mixed-phase windings, and the like. However, there is no improvement in the slots in which the windings are placed, and practice has shown that such an improved design, although effective, is not as great.
Disclosure of Invention
In view of this, an object of the present invention is to provide a method for designing a stator of a three-phase motor, that is, a stator core and a stator winding of the three-phase motor are designed according to the basic rule of three-phase alternating current (see fig. 1), so that the waveform of magnetomotive force generated by the stator winding of the three-phase motor is substantially a sine wave, and the roundness of a rotating magnetic field synthesized by the waveform is better, thereby reducing the loss and cost of the motor and improving the comprehensiveness of torque, vibration, and the like.
In the present application, it is preferable that the design method specifically includes:
1. according to the prior art, the number of slots Z of a stator core of a three-phase motor is determined and expressed as a formula Z which is 3 pn. In the formula, p is the number of poles of the motor, and n is the number of slots per pole and phase of the stator core of the motor determined by the prior art. The majority of small and medium-sized motors are 2-8 slots, the number of poles is small, and the number of poles is large when the power is large.
2. Determining each phase of each poleNumber q of slots of stator windingAccount forAnd the number of laminated slots q per side of each phase winding per poleStack。qAccount forCan be expressed as the formula: q. q.sAccount forN +1, 2, and 3, the number of poles is small, and the power is large. q. q.sStackThe number of poles is small, and the power is large, and can take 1, 2 and 3.
3. And calculating the space electrical angle from each slot in each phase of winding of each pole to the center of the magnetic pole of each phase of winding, and calculating the corresponding sine value according to the space electrical angle. The sine value can be expressed as a formula
Where s is the slot pitch from a slot to the center of the phase pole.
4. And calculating the number of turns to be distributed to each slot and the corresponding slot area according to the sine value of each slot and the percentage of the total sine value of each phase of winding of each pole.
5. The following consideration is given: the waveform of the magnetomotive force generated by the three-phase winding is as close to a sine wave as possible, and the magnetic flux density of the yoke part of the iron core at the overlapping slot position in each phase winding of each pole is not too high. Therefore, the number of winding turns in the winding stack slot of each phase of each pole and the slot area are appropriately adjusted. Generally, the theoretical value is preferably reduced by 15%.
The application provides a three-phase motor stator's design method for design three-phase motor stator, three-phase motor stator is formed by the stator punching, the stator punching is including being used for the groove of winding stator winding, and three-phase motor stator's design method includes:
planning, namely determining the number Z of the slots of the stator punching sheet to be 3p multiplied by n on the basis of the number of the slots of the existing stator;
a calculation step of calculating the number q of the slots occupied by each phase of winding of each pole according to the number Z of the slots of the stator lamination obtained in the planning stepAccount for＝n+1、2、3；
Wherein p is the number of magnetic poles of the stator winding, n is the number of slots of each phase of each pole of the conventional stator punching sheet, and Z, n and p are positive integers;
the calculating step further comprises the step of calculating the number of winding turns in each slot of each phase winding of each pole according to the number of slots occupied by each phase winding of each pole, so that the number of winding turns in each slot of each phase winding of each pole is distributed according to the cosine law, and the number of winding turns of the slot positioned in the middle of each phase winding of each pole is larger than the number of winding turns of the slots positioned on two sides of each phase winding of each pole.
According to the design method of the three-phase motor stator, the obtained three-phase motor stator has the advantages that the waveform of the magnetomotive force is closer to a sine wave, so that the roundness of a rotating magnetic field is more ideal, the loss and the cost of the motor are effectively reduced, and the comprehensive performances such as vibration are improved.
Preferably, the calculating step further comprises:
calculating the number q of the overlapped slots of two adjacent windings of each pole and each phaseStack：＝1、2、3。
Preferably, the calculating step further comprises:
determining the magnetic pole center of each phase winding of each pole;
calculating the sine value q of the space electrical angle from each slot in each phase winding of each pole to the center of the magnetic polesin：
According to sine value qsinCalculating the percentage of the number of turns of the winding in each slot to the total number of turns of the winding of each pole;
wherein s is the slot pitch from any slot in each phase winding of each pole to the center of the phase magnetic pole, s is the number of slots from the center line of the magnetic pole to any slot in each phase winding of each pole, and s is a positive integer.
Preferably, said dependence on sine value q issinCalculating the percentage of the number of turns of the winding in each slot to the total number of turns of the winding per pole comprises:
the number of turns of the windings in each slot as a percentage of the total number of turns of the windings per pole is the ratio of the sine of each slot in each phase of the windings per pole to the sum of the sine of all slots in each phase of the windings per pole.
Preferably, the planning step further comprises:
the slot area of the laminated slots is set to be reduced by 15% on the basis of 2 times of the inner-located slots of any one of the adjacent two windings of each phase of each pole.
Preferably, the calculating step further comprises: the area of the cross-section of the respective slot is determined in accordance with the number of winding turns in the respective slot in each phase winding of each pole.
In order to make the aforementioned objects, features and advantages of the present application more comprehensible, preferred embodiments accompanied with figures are described in detail below.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.
FIG. 1 shows a schematic diagram of a three-phase AC waveform;
fig. 2 shows a schematic diagram of the number of slots occupied by each phase winding per pole of a 24-slot 2-pole three-phase motor stator provided according to an embodiment of the application.
Reference numerals:
1-yoke.
Detailed Description
The technical solutions of the present application will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.
In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present application.
Fig. 2 is an exemplary embodiment of a stator design method for a three-phase motor of the present application, a 24-slot 2-pole three-phase motor.
The number of slots of the stator of the motor is determined as 24 slots according to the prior art, the number of slots of each pole and each phase of the stator iron core is 4 slots. Is expressed by the formula: z is 3 pn. In the formula, Z is the number of slots of the stator core, p is the number of poles of the motor, and n is the number of slots of each phase of each pole of the stator core. "3" indicates the number of phases of the stator winding of the motor. The value of n is generally 2 to 8, the number of poles is small, and the value of n is large when the power is large. Further, the number q of occupied slots of each pole and each phase of the stator winding of the motor is determinedAccount forCan be expressed as formula qAccount forN +1, 2, and 3 are numbers of slots per winding per pole and phase greater than the number of slots per core per pole by 1 to 3 (the number of poles is small, the power is high, and the value is large). This example has 1 more slot, that is: take a phase winding as an example (for convenience of description, it is positioned in U-phase).
Such as: groove 11 to groove15 for 5 slots, being the 1 pole of the U-phase winding, and slots 23 to 3 are also 5 slots, being the other pole of the U-phase winding. (since the three phases are symmetrical and identical, the other two phases need not be described, as will be described later). Further, as shown in fig. 2, the slot 3, the slot 7, the slot 11, the slot 15, the slot 19 and the slot 23, and 6 slots, in which adjacent two-phase windings are placed, which are called stacked slots, can be denoted as qStackThe number of the stacked slots on one side of each pole of each phase winding is 1 to 3, and the number of the poles is small, and the power is large. In this embodiment, 1 is taken, i.e. one side of each phase winding of each pole, and there are only 1 laminated slots. As is evident from fig. 2, the lamination slots are always at the junctions of the different two phase windings, or, in other words, on both sides of each phase winding of each pole. The number of laminated slots refers to the number of laminated slots on one side of each phase of winding of each pole. Taking the phase of fig. 2U as an example, it is referred to as either slot 11 or slot 15 or slot 23 or slot 3.
Further, the magnetic pole center of each phase winding of each pole is determined.
Still taking the U-phase in fig. 2 as an example, according to the basic rule of the electromagnetic theory, the two stages of the U-phase winding are: slot 11 to slot 15 and slot 23 to slot 3, and therefore, the magnetic pole center of the U-phase winding, at slot 7 to slot 19. The description by words is as follows: the center of the magnetic pole of each phase winding of each pole is positioned between the adjacent two pole windings of the same phase winding, and is a straight line passing through the center of the plane of the stator core, and the two sides of the straight line are separated by 180 degrees.
Further, the slot pitch of each slot in each phase winding of each pole to the center of the magnetic pole thereof is calculated. The U phase in fig. 2 is also taken as an example. As is apparent from fig. 2, slots 3 and 11 to slot 7 (pole center), slots 15 and 23 to slot 19 (pole center), all have a slot pitch of 4, while slots 2 and 12 to slot 7 (pole center), slots 14, 24 to slot 19 (pole center), all have a slot pitch of 5. And slots 1 and 13 are all 6 slot pitch to the pole center (slot 7, or slot 19).
Further, according to the groove distance, the sine value of the corresponding electrical angle is calculated. Can be formulated as:
also taking fig. 2U phase as an example:
grooves 3, grooves 11, grooves 15, grooves 23, all having a pitch of 4, then
The groove distance of the grooves 2, 12, 14 and 24 is 5, then
The groove distance of the grooves 1 and 13 is 6, then
And further, calculating the number of turns of the winding of each slot according to the percentage of the sine value of each slot in the total sine value of the winding of each pole and each phase.
Also taking fig. 2U phase as an example, such as: the total sine of slots 11 through 15 is:
2×(0.866+0.966)+1＝4.664
since slots 11 and 15 are identical, the percentage of turns is: (0.866/4.664) × 100% ═ 18.6%. Slots 12 and 14 are identical and have a percentage of turns: (0.966/4.664) × 100% ═ 20.7%.
The percentage of turns in slots 1 and 13 is: (1/4.664) × 100% ═ 21.4%.
That is, the number of slot turns for slot 11 and slot 15 each account for 18.6% of the total number of turns per phase per pole. And slots 12 and 14, each account for 20.7% of the total turns per phase per pole; the grooves 1 and 13 each account for 21.4%.
Due to symmetry, the U phase has slots 23 through 3, which are identical to slots 11 through 15. The number of winding turns in each slot is determined and the area of the corresponding slot is determined.
Further, it should be noted that: (as is evident from fig. 2) 6 superimposed slots in the stator winding, namely: slots 3, 7, 11, 15, 19, 23, in which the windings of two adjacent phases are placed, so that the number of turns of the winding in each slot is 2 times the calculated value, i.e. 2 x 18.6%. 37.2%, the area of the corresponding slot is enlarged by 1 time, and the enlargement of the slot area inevitably causes the width of the yoke part of the core at the stacked slot to be greatly reduced, so that the magnetic flux density at the position is high when the motor operates. As a result, although the magnetomotive force waveform generated by the winding is a sine wave, the magnetic path condition of the core yoke 1 is poor. Therefore, it is necessary to appropriately reduce the number of winding turns of the laminated slots from the overall viewpoint, and to reduce the slot area of the laminated slots, so that the width of the core yoke 1 at the laminated slots is not excessively small. Generally, the number of winding turns in the stacked slots, and the corresponding slot area, is reduced by about 15% based on the calculated value. Therefore, the waveform of the magnetomotive force generated by the three-phase winding is basically close to a sine wave, and the magnetic flux density of the yoke part at the laminated slot of the stator core is proper and not too high when the yoke part works.
The above description is only a preferred embodiment of the present application, and not intended to limit the scope of the present application, and all changes that can be made in the details of the description and drawings, or directly/indirectly implemented in other related technical fields, are intended to be embraced therein without departing from the spirit of the present application.
Claims (4)
1. A design method of a three-phase motor stator comprises stator core design and winding design, and is characterized in that: the groove shape of the stator winding and the corresponding stator core of the three-phase motor are designed according to the basic rule of three-phase alternating current, wherein the basic rule of the three-phase alternating current is that each phase of the three-phase alternating current continuously changes and runs according to the rule of sine waves, and the three-phase alternating current respectively have the basic rule of overlapping with another adjacent phase by 60 electrical angles before and after the zero crossing point of positive and negative half-wave conversion.
2. The method of designing a stator for a three-phase motor according to claim 1, wherein: stator of current three-phase motorDetermining the number q of slots occupied by each pole and each phase of the winding on the basis of the number of slots of the iron coreAccount forAnd is expressed by the formula: q. q.sAccount forN +1, 2 and 3, wherein n is the number of slots of each pole and each phase of stator core, n is an integer, the number of stacked slots on one side of each pole and each phase of winding is determined, and the number is expressed as: q. q.sStack＝1、2、3。
3. The method of designing a stator for a three-phase motor according to claim 2, wherein: calculating the slot pitch, the space electrical angle and the sine value q of the corresponding slots from the slots to the magnetic field center of each phase winding of each polesinIs expressed by formula as
In the formula, Z is the number of slots of the stator core, p is the number of poles of the motor, s is the slot pitch from a certain slot to the center of a magnetic pole of the certain slot, and the number of winding turns distributed to each slot and the corresponding slot area are calculated according to the sine value.
4. A method of designing a stator for a three-phase motor according to claim 3, wherein: the number of turns in the laminated slots in each phase winding per pole and the corresponding slot area are suitably adjusted such that: the waveform of the magnetomotive force generated by the three-phase winding is as close to a sine wave as possible, and meanwhile, the width of the iron core yoke part at the laminated slot is not too small, and the magnetic flux density is not too high during working.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111165233.3A CN113765244B (en) | 2021-09-30 | 2021-09-30 | Design method of three-phase motor stator |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111165233.3A CN113765244B (en) | 2021-09-30 | 2021-09-30 | Design method of three-phase motor stator |
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| CN113765244A true CN113765244A (en) | 2021-12-07 |
| CN113765244B CN113765244B (en) | 2022-10-21 |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204681172U (en) * | 2015-04-10 | 2015-09-30 | 闫继成 | Single-phase two pole motors |
| CN208581096U (en) * | 2018-08-31 | 2019-03-05 | 广东美芝制冷设备有限公司 | Stator component, motor and compressor |
| CN210092979U (en) * | 2019-07-09 | 2020-02-18 | 山西电机制造有限公司 | Stator punching sheet with large and small slots, wherein each pole and each phase of slots are 4 |
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2021
- 2021-09-30 CN CN202111165233.3A patent/CN113765244B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204681172U (en) * | 2015-04-10 | 2015-09-30 | 闫继成 | Single-phase two pole motors |
| CN208581096U (en) * | 2018-08-31 | 2019-03-05 | 广东美芝制冷设备有限公司 | Stator component, motor and compressor |
| CN210092979U (en) * | 2019-07-09 | 2020-02-18 | 山西电机制造有限公司 | Stator punching sheet with large and small slots, wherein each pole and each phase of slots are 4 |
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| CN113765244B (en) | 2022-10-21 |
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