JP2003189565A - Induction motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce loss and improve efficiency by using winding as conductor of a rotor and reducing a cross current in an induction motor of six poles. <P>SOLUTION: A rotor 1 of six-pole constitution is arranged inside a stator which generates a rotating magnetic field, and e.g. twelve trenches 1b are formed in the circular arc direction, at an equal interval in the rotor 1. The direction of the trenches 1b is made the axial direction of a rotating shaft 2. In the trenches 1b, two of short-circuit windings 3a, 4a, 5a of a first to a third winding groups 3, 4, 5 which turn to short-circuit conductors are subjected to lap winding at two pitches, and the first to third winding groups 3, 4, 5 are adjacently arranged. By the rotating magnetic field generated from the stator, induction short-currents flow in opposite directions through the short- circuit windings 3a, 4a, 5a. By the interaction between the rotating magnetic field by the stator and the induction short-circuit currents, turning forces in the same rotating direction are applied to the two short-circuit conductors, thereby rotating the rotor 1. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a 6-pole induction motor used in consumer equipment (for example, air conditioners) and industrial equipment, and more specifically, a novel induction motor using a winding as a rotor conductor. It is about.

[0002]

2. Description of the Related Art An induction motor has, as a basic structure, a rotor arranged inside a stator having a winding for generating a rotating magnetic field, but the rotor is not provided with a fixed magnetic pole. . That is, the rotor has no winding such as the stator winding.

When the rotor having the short-circuit conductor is arranged in the rotating magnetic field of the stator, a short-circuit induced current flows through the rotor. Rotational force (torque) is generated by the interaction of both the rotating magnetic field and the short-circuit induced current, and the rotor rotates. Such induction motors are widely used in home appliances and industrial machines from the viewpoints of simplicity and economy.

[0004]

By the way, in the above induction motor, conventionally, the main body (short-circuit conductor) of the rotor is manufactured mainly by casting a conductor by aluminum die casting. However, according to this, since it is difficult to insulate the rotor core from the aluminum conductor, a transverse current (current flowing in the circumferential direction of the rotor core) that does not contribute to torque flows in the rotor core, which causes an increase in loss and increases the efficiency of the motor. There was a drawback that it lowered.

Further, since it is difficult to use copper having high electric conductivity as the conductor, since aluminum conductor is used, electric loading and magnetic loading are small, resulting in torque shortage and low efficiency. there were.

The present invention has been made to solve the above problems, and an object thereof is to adopt a winding method using a winding as a rotor conductor to eliminate a traverse current and reduce loss. It is an object of the present invention to provide an induction motor with improved efficiency and, as a result, a wider range of use as a 6-pole motor.

[0007]

In order to achieve the above object, the present invention is a 6-pole induction motor in which a rotor is arranged inside a stator that generates a rotating magnetic field. The first to the third winding group consisting of the above windings are used, and the windings of the first to the third winding group are respectively wound, and an induced short-circuit current is generated in the windings by the rotating magnetic field. It is characterized by making it flow.

In the present invention, the rotor has a size of 2 × 3 × n.
Grooves (n; a positive integer of 2 or more) in the axial direction of the rotating shaft,
In addition, it is preferable that the windings are formed at equal intervals in the circumferential direction, and n windings of the first to third winding groups are overlapped with each other by n pitches through these grooves. According to this, a groove having an integral multiple of 6 is formed in the rotor, and the winding as the short-circuit conductor of the rotor can be appropriately provided.

Further, 2 × (3 × n + 1) (n: a positive integer of 2 or more) grooves are formed in the rotor in the axial direction of the rotating shaft and at equal intervals in the circumferential direction. The windings of the first and second winding groups are respectively n pitches through the grooves.
The first winding group and the second winding group are set to 1 by applying n windings of the third winding group at an n + 1 pitch.
By forming a slot (vacant groove) and forming the third winding group between the first and second winding groups by providing a vacant groove in the center of the third winding group. Also, it is possible to appropriately apply the winding as the short-circuit conductor of the rotor.

In the present invention, the main winding and the auxiliary winding are wound around the stator by concentrated winding or distributed winding,
A capacitor induction motor can be obtained. in this case,
In particular, it is preferable that 12 grooves are formed on the inner peripheral side of the stator, and the main winding and the auxiliary winding are concentratedly wound through these grooves. As a result, a highly efficient capacitor induction motor using a novel rotor can be realized, and the range of use of the capacitor induction motor can be expanded.

On the other hand, a three-phase AC induction motor can be obtained by winding the three-phase windings on the stator by concentrated winding or distributed winding. In this case, it is particularly preferable that 18 grooves are formed on the inner peripheral side of the stator and the three-phase winding is concentratedly wound through these grooves. As a result, a highly efficient three-phase AC induction motor using a novel rotor can be realized, and the range of use of the three-phase AC induction motor can be expanded.

All the windings applied to the rotor are preferably short-circuited windings. Further, aluminum, aluminum alloy, copper or copper alloy is used for all the windings applied to the rotor, and any one of pressure welding, welding, soldering or crimping with crimp terminals is used as a connection method of the windings. Adopt it.

As a result, it is possible to use a copper-based material as the winding of the short-circuiting conductor of the rotor, that is, it is possible to achieve high torque and high efficiency, and the connection of the short-circuiting winding is existing. It can be realized with technology.

It is preferable to electrically insulate between the windings provided through the grooves of the rotor. Similarly, electrical insulation may be provided between the rotor core of the rotor and the winding.
The groove of the rotor may be an open hole or a closed groove.

As a result, when an induced short-circuit current flows through the winding, the induced short-circuit current does not flow through the rotor core of the rotor, that is, the transverse current is extremely small, loss is small, and high efficiency can be achieved. .

In the rotor, electromagnetic steel plates are punched by an automatic laminating die and laminated to obtain a rotor core, and a groove is preferably skewed when laminating. As a result, the short-circuit winding as the short-circuit conductor of the rotor is provided in the skewed groove, and the torque can be improved.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described with reference to FIGS.

The induction motor of the present invention is a 6-pole motor,
The rotor has 2 × 3 × n (n; 2
The above positive integer) grooves are formed, and windings of n pitch (closed circuit of short-circuit winding; hereinafter referred to as short-circuit winding) are formed on the 2 × 3 × n grooves, and the n-pitch is formed. The first winding group in which n short-circuited windings are overlapped and the second and third winding groups having the same configuration as the first winding group are sequentially formed, and 3 ×
N windings are applied.

More specifically, as shown in FIGS. 1 and 2, in this embodiment, the rotor 1 includes twelve (n = 2) grooves 1b on the outer peripheral side of the rotor core (rotor core) 1a. Are formed at equal intervals (30 degree intervals) in the axial direction of the rotary shaft 2 and in the circumferential direction, and two short pitch windings 3a of 2 pitches are superposed at intervals of 1 pitch through these 12 grooves 1b. The first winding group 3 is wound to form two first pitch groups 3 and two short pitch windings 4a having two pitches are overlapped with each other at every one pitch to form the second winding group 4. Along with the formation of the second winding group 4, two short-circuit windings 5a of 2 pitches are overlapped with each other at intervals of 1 pitch to form a third winding group 5, and 6 windings are formed. I will give it.

According to the rotor 1, twelve short-circuit conductors formed by the first to third winding groups 3, 4 and 5 are continuous,
Since one pole is formed by the two short-circuited windings, the total number of poles is six.

As shown in FIGS. 3 and 4, on the stator 6 side, 12 grooves are formed on the inner peripheral side, that is, on the inner peripheral side of the yoke portion 6a having a predetermined width. Twelve teeth 6b are formed at intervals of 30 degrees.
Concentrated windings 7a, 7b, 7c, 7d, 7e, 7
f, 8a, 8b, 8c, 8d, 8e, 8f, and windings 7a, 7b and winding 7 provided on the facing teeth 6b.
c, 7d and windings 7e, 7f as the main windings, and the remaining teeth 6b have windings 8a, 8b, windings 8c, 8d and windings 8e, 8f as the auxiliary windings. Become.

In the induction motor having the above structure, since the rotating magnetic field is generated in the stator 6, the main windings 7a, 7b, 7c, 7d, 7e, 7f and the auxiliary winding 8a, as shown in FIG. 8b, 8c, 8d, 8e, 8f are connected, that is, the parallel circuit of the auxiliary windings 8a, 8b, the auxiliary windings 8c, 8d and the auxiliary windings 8e, 8f and the capacitor 9 are connected in series, and A parallel circuit of main windings 7a, 7b, main windings 7c, 7d and main windings 7e, 7f is connected in parallel to the circuit, and an AC power supply 10 is supplied to the parallel circuit. The main winding and the auxiliary winding may be connected by another connection method. As a result, the induction motor becomes a capacitor induction motor.

In this capacitor induction motor, when a rotating magnetic field is generated in the stator 6, an induced short-circuit current flows in the short-circuit windings 3a, 4a, 5a of the rotor 1 due to this rotating magnetic field. There are two short-circuit conductors formed by these short-circuit windings 3a, 4a, and 5a, and the induced short-circuit currents of these two short-circuit conductors flow in opposite directions (that is, different polarities). Therefore, due to the interaction between the rotating magnetic field generated in the stator 6 and the induced short-circuit current, the two short-circuit conductors formed by the short-circuit windings 3a, 4a, 5a exert a rotational force (torque) in the same rotation direction, and the rotor is rotated. 1 rotates.

In the above embodiment, the number of grooves of the rotor 1 is 12
Although the number of grooves is 2, the number of grooves is 2 × 3 × n and the number of windings is n. The same action and effect can be obtained even if 3n windings are formed depending on the wire group, and the concentrated winding is used as the winding of the stator 6, but it may be distributed winding.

By the way, in order to manufacture the rotor 1,
The electromagnetic steel plates (belt-shaped) are punched and laminated by an automatic laminating die, and it is preferable to obtain the rotor core 1a by laminating the grooves 1b so as to skew them. According to this, the short-circuit windings 3a, 4a, 5a are skewed, and the torque of the capacitor induction motor can be increased.

The groove 1b of the rotor 1 is preferably an open hole as shown in FIG. 1 in view of the ease of manufacturing the rotor 1, but it may be a closed hole. It is preferable that the inside of the groove 1b be insulated. That is, the rotor core 1a and the short-circuit windings 3a, 4a, 5a are electrically insulated from each other so that the rotor core 1a and the short-circuit windings 3a, 4a, 5a are provided.
It is electrically insulated from a, the traverse current becomes as small as possible, the loss does not increase, and the efficiency of the motor can be improved.

In order to suppress the transverse current and loss by insulating the wires of the short-circuit winding 3a and the wires of the short-circuit winding 4a and the short-circuit winding 5a provided in each groove 1b, enamel is applied to these windings. It is preferable to use a winding wire having an insulating film applied thereto.

Short-circuit windings 3a, 4a, 5a of the rotor 1
As the short-circuit conductor, aluminum, aluminum alloy, copper, copper alloy, or the like may be used, and the connection method may be pressure welding, welding, soldering, or crimping with a crimp terminal.

As a result, particularly when a copper-based material is used for the short-circuit windings 3, 4a and 5a, higher torque and higher efficiency can be expected as compared with the aluminum-based material. Also, short-circuited winding 3
An existing technique can be used as the connection method of a, 4a, and 5a.

Here, the short-circuit windings 3a, 4a of the rotor 1,
5a will be supplementarily described. Since the winding forms a short circuit, the ampere-turn TA generated by the induced voltage is constant if the space factor or the usage amount is the same. To explain the reason, the voltage induced in the short-circuited winding is expressed by the following formulas 1 and 2.

[0031]

[Equation 1]

[0032]

[Equation 2]

N is the number of groove conductors, and the rotor groove conductor cross-sectional area is a value obtained by multiplying the square of the conductor diameter d by the number N of conductors (constant).
Where φ is the main magnetic flux (constant), R is the winding resistance,
X is the reluctance of the winding.

When the number of groove conductors is one (N = N1 =
1), the ampere-turn TA1 can be represented by i1 · N1, and when the number of groove conductors is plural (N = N2), the ampere-turn T
A2 can be represented by i2 · N2. Ampere turns TA1 and T
When compared with A2, the following formula 3 is obtained, that is, TA2 /
TA1 = 1.

[0035]

[Equation 3]

In the above formula 3, when the number of groove conductors is one, the diameter of the winding wire to be applied to the groove is increased, and the winding amount to be applied when the number of groove conductors to be used is plural. By setting the same as the used amount, the ampere-turn AT becomes the same when the number of groove conductors is set to one and the number of groove conductors is set to one.

Therefore, if the rotor groove conductor cross-sectional areas, that is, the space factors, are made equal, the motor performance is the same regardless of whether there is one winding or a plurality of windings. It can be said that the torque characteristic of the induction motor by the rotor 1 according to the invention is equivalent to that of the die cast rotor.

5 to 7 are schematic configuration diagrams of the induction motor according to the second embodiment. According to this, the rotor is 2 × (3n +) on the outer peripheral side of the rotor core (rotor core).
1) (n; positive integer of 2 or more) grooves are formed,
Forming a first winding group in which n pitch windings (closed circuit of short-circuit winding; hereinafter referred to as short-circuit winding) are overlapped and wound in × (3n + 1) grooves, and the first winding is formed. A second winding group having the same configuration as the wire group is formed by placing 1 slot (vacant groove) with the first winding group, and n short-circuit windings of n + 1 pitch are overlapped and an empty groove is formed in the center thereof. Forming a third short circuit winding adjacent to the first and second short circuit windings, and
N windings are applied.

More specifically, as shown in FIG.
The rotor 20 of the induction motor according to the second embodiment has 14 (n = 2) grooves on the outer peripheral side of the rotor core (rotor core) in the same manner as the rotor 1 of the first embodiment. The first winding group 21 and the two short-circuit windings 21a, which are formed at equal intervals (360/14 degrees) in the axial direction and in the circumferential direction, and which include two short-circuit windings 21a, are formed through these 14 grooves. The second winding group 22 composed of the short-circuited windings 22a is formed by arranging one slot (vacant groove) from the first winding group 21 and the third winding-group 23 composed of two short-circuited windings 23a. Are adjacent to the first and second winding groups 21 and 22.

The first winding group 21 has two 2-pitch short-circuit windings 21a which are stacked one by one, and the second winding group 22 has two 2-pitch short-circuit windings 22a. The third winding group 23 is formed by stacking two pitched short-circuit windings 23a at a pitch, and forming an empty groove in the center of the third winding group 23. It becomes. That is,
In this rotor 20, six short-circuit conductors are continuous with a groove, and there are two sets of the six short-circuit conductors.
Similar to the embodiment, the total number of poles is six.

As shown in FIGS. 6 and 7, the stator 24 of the induction motor according to the second embodiment has 18 grooves, that is, a predetermined width inside the yoke portion 24a on the outer peripheral side. 18 teeth 24b are formed at intervals of 20 degrees,
Concentrated windings 25a, 25b, 25 around these teeth 24b
c, 25d, 25e, 25f, 26a, 26b, 26
c, 26d, 26e, 26f, 27a, 27b, 27
c, 27d, 27e, 27f.

Regarding the above 18 windings 25a to 27f, the windings 25a, 25 provided on the teeth 24b facing each other are provided.
b, windings 25c and 25d and windings 25e and 25f, three pairs are U-phase windings, and windings 26a and 26b, winding 26c,
26d and the windings 26e and 26f are made into V-phase windings, and the windings 27a and 27b, windings 27c and 27d and windings 27e and 27f are made into W-phase windings.

In the induction motor having the above structure, in order to generate a rotating magnetic field in the stator 24, for example, 18 windings 25a to 27f are Y-connected as shown in FIG. 7, and three windings are connected to the Y-connection. Supply phase AC power.

In this case, for the U phase, the winding 25a,
25b and windings 25c and 25d and windings 25e and 25f are connected in parallel, and for the V phase, windings 26a and 26b and windings 26c and 26d and windings 26e and 26f are connected in parallel, and W Regarding phases, windings 27a and 27b, windings 27c and 27d, and windings 27e and 27f are connected in parallel. The windings of the stator 24 may be connected by another connection method.

As a result, the induction motor becomes a 3-phase 6-pole induction motor. In this 3-phase 6-pole induction motor, when a rotating magnetic field is generated in the stator 24, an induced short-circuit current flows in the short-circuit windings 21a, 22a, 23a of the rotor 20 (that is, different poles) due to the rotating magnetic field. .

The short-circuit windings 21a, 22a and 23a are two short-circuit conductors, respectively. Since these short-circuit conductors operate in the same manner as in the first embodiment, the rotating magnetic field of the stator 24 and the induced short-circuit current are generated. Short circuit winding 2 due to interaction
Rotational forces (torques) in the same rotation direction act on the two short-circuit conductors 1a, 22a, and 23a, and the rotor 10 rotates.

In the second embodiment, the rotor 20
Although the number of grooves of 14 is set to 14, the number of grooves of 2 × (3n + 1) is formed. For example, two winding groups with n windings at n pitch and one winding with n windings at n + 1 pitch are formed. Even if the winding group is provided, the same action and effect can be obtained. Further, although the concentrated winding is used as the winding of the stator 24, it may be distributed winding.

The rotor 20 and the stator 24 are manufactured in the same manner as in the first embodiment. For example, the groove (open hole or closed hole) of the rotor 20 is skewed.
The inside of the groove (open hole or closed hole) is electrically insulated. In addition, the short-circuit windings 21a, 22 of the rotor 20
The materials a and 23a are made of the same material and connection method as those described in the first embodiment, and are insulated.

Therefore, by adopting the winding method using the copper wire or the aluminum wire as the short-circuit conductor of the rotor 20, the transverse current is extremely small and the loss is small as in the first embodiment. , The motor efficiency is improved.
As a combination of the rotors 1 and 20 and the stators 6 and 24, a 6-pole induction motor can be realized even in cases other than those described above.

[0050]

As described above, according to the present invention,
First to third short-circuit conductors of the rotor inside the stator
Of the first to third winding groups, and the induced short-circuit current is caused to flow through the windings by the rotating magnetic field of the stator. Therefore, as compared with the short-circuit conductor formed by aluminum die casting, the transverse current in the rotor is extremely small, the loss is small, the efficiency is improved, and the useful range is expected to be expanded as a 6-pole motor.

[Brief description of drawings]

FIG. 1 is a schematic plan view showing a rotor of an induction motor according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram for explaining the rotor of FIG.

FIG. 3 is a schematic plan view for explaining a stator of the induction motor according to the first embodiment.

FIG. 4 is a schematic circuit diagram for explaining a connection of windings formed on the stator shown in FIG.

FIG. 5 is a schematic diagram for explaining a configuration of a rotor of an induction motor according to a second embodiment of the present invention.

FIG. 6 is a schematic plan view for explaining a stator of an induction motor according to a second embodiment of the present invention.

7 is a schematic circuit diagram for explaining the connection of windings applied to the stator shown in FIG.

[Explanation of reference numerals] 1,20 rotor 1a rotor core (rotor core) 1b groove 2 rotary shafts 3a, 4a, 5a short-circuit winding (conductor of rotor 1; winding of closed circuit) 3,21 first winding Wire group 4,22 Second winding group 5,23 Third winding group 6,24 Stator 6b, 24b Teeth 7a-7f, 8a-8f Stator side winding 21a-23a Short-circuit winding (rotation) Conductor of child; winding of closed circuit) 25a to 25f, 26a to 26f, 27a to 27f Winding on the stator side

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H02K 3/51 H02K 3/51 Z 17/08 17/08 A G 17/12 17/12 A F term ( reference) 5H013 DD03 FF03 LL00 MM00 NN01 NN05 NN06 PP01 PP03 5H603 AA04 BB06 BB07 BB08 BB12 CA01 CA02 CB02 CB03 CB05 CB12 CB23 CB26 CC04 CC05 CC11 CC17 CD05 CD21 CE13 CE14 CE16 EE01 EE04 5H604 BB01 BB09 BB14 CC01 CC02 CC05 CC14 CC15 CC16 PB02 PB03 QB03

Claims (13)

[Claims] 1. A six-pole induction motor in which a rotor is arranged inside a stator that generates a rotating magnetic field, wherein a conductor of the rotor includes first to third winding groups each including a plurality of windings. The induction motor is characterized in that the windings of the first to third winding groups are overlapped with each other, and an induced short-circuit current flows through the windings by the rotating magnetic field. 2. The rotor is formed with 2 × 3 × n (n; a positive integer of 2 or more) grooves in the axial direction of the rotating shaft and at equal intervals in the circumferential direction. The induction motor according to claim 1, wherein n windings of each of the first to third winding groups are overlapped with each other through a groove at an n pitch. 3. The rotor is formed with 2 × (3 × n + 1) (n; a positive integer of 2 or more) grooves in the axial direction of the rotating shaft and at equal intervals in the circumferential direction. , N windings of the first and second winding groups are respectively provided through the grooves at an n pitch, and n + windings of the third winding group are provided.
N pitches are formed at one pitch, the first winding group and the second winding group are formed with one slot (vacant groove) formed, and the third winding group is formed into the first and second winding groups. 2. An empty groove is formed between groups in the center of the third winding group.
Induction motor described in. 4. The induction motor according to claim 1, wherein the stator is provided with a main winding and an auxiliary winding by concentrated winding or distributed winding to form a capacitor induction motor. 5. The capacitor induction motor according to claim 4, wherein 12 grooves are formed on the inner peripheral side of the stator, and the main winding and the auxiliary winding are concentratedly wound through these grooves to form a capacitor induction motor. Induction motor. 6. The induction motor according to claim 1, wherein the stator is provided with a three-phase winding by concentrated winding or distributed winding to form a three-phase AC induction motor. 7. The three-phase AC induction motor according to claim 6, wherein eighteen grooves are formed on the inner peripheral side of the stator, and three-phase windings are concentratedly wound through these grooves to form a three-phase AC induction motor. Induction motor. 8. The induction motor according to claim 1, wherein all the windings applied to the rotor are short-circuited windings. 9. All of the windings applied to the rotor are made of aluminum, aluminum alloy, copper or copper alloy, and the windings are connected by pressure welding, welding, soldering or crimping with crimp terminals. The induction motor according to any one of claims 1 to 8, wherein the induction motor is adopted. 10. The electrical insulation is provided between the windings provided through the grooves of the rotor.
Induction motor according to paragraph. 11. The induction motor according to claim 2, wherein electrical insulation is provided between the rotor core of the rotor and the winding. 12. The induction motor according to claim 2, wherein each groove of the rotor is an open hole or a closed groove. 13. The rotor according to claim 2, wherein the rotor is obtained by punching electromagnetic steel sheets with an automatic laminating die and laminating the rotor steel sheets to obtain a rotor core, and skewing grooves when laminating the rotor core. Induction motor.