KR20200093508A - Permanent Magnet Synchronous Motor - Google Patents

Abstract

The present invention relates to a permanent magnet synchronous motor, and more particularly, to a permanent magnet synchronous motor capable of reducing iron loss, the motor is installed in the housing and the housing, the stator consisting of a winding retainer including a winding ; And an inner rotor core coupled to the rotor shaft passing through the housing, a permanent magnet installed, an outer rotor fixing plate spaced apart from the inner rotor core at a predetermined distance and coupled to the rotor shaft, and the outer rotor. And a rotor composed of an outer rotor core installed to face the permanent magnet at a predetermined distance from the fixed plate.

Description

Permanent Magnet Synchronous Motor

The present invention relates to a permanent magnet synchronous motor, and more particularly, to a permanent magnet synchronous motor capable of reducing iron loss.

HSG (Hybrid Starter Generator) is a device that is mechanically connected to an automobile engine and serves as a starter and a generator at the same time, and is also called an Integrated Starter Generator (ISG).

The HSG enables quick start by turning the crankshaft of the engine when the vehicle starts, charges the discharged battery through the generator mode or regenerative braking while driving, and also assists the engine torque momentarily during acceleration.

Permanent magnet synchronous motors (PMSMs), which are superior to field winding motors or induction machines, are mainly used as HSG motors.

The structure of a general PMSM is largely composed of a rotor and a stator, the rotor is composed of a core using an electric steel plate and a permanent magnet attached or inserted into the core, and the stator is composed of a core and a winding using an electric steel plate.

Unlike non-permanent magnet equipment, iron losses are generated only when it is loaded. PMSM always generates iron losses when rotated regardless of whether or not it is loaded. Since the rotor of the HSG is mechanically connected to the crankshaft and rotates with the crankshaft, the HSG using PMSM is always in a state where iron loss occurs unless the engine is stopped.

The iron loss generated in PMSM is the cause of HSG heat generation and acts as a load on the engine, which degrades the system efficiency of the vehicle.

Accordingly, the present invention is to solve the problems of the prior art as described above, the object of the present invention is to provide a permanent magnet synchronous motor capable of reducing iron loss.

Permanent magnet synchronous motor according to an embodiment of the present invention for achieving the above object is installed in the housing and the housing, the stator consisting of a winding retainer including a winding; And an inner rotor core coupled to the rotor shaft passing through the housing, a permanent magnet installed, an outer rotor fixing plate spaced apart from the inner rotor core at a predetermined distance and coupled to the rotor shaft, and the outer rotor. And a rotor composed of an outer rotor core installed to face the permanent magnet at a predetermined distance from the fixed plate.

It is preferable that the winding retainer includes a plurality of grooves in which the winding is located.

The winding retainer is composed of a cylindrical inner portion and a plurality of extension portions extending vertically from the inner portion, and the windings are positioned between adjacent extension portions.

The winding retainer extends vertically on both sides at the ends of the plurality of extension portions to further include a fixing portion.

The winding retainer is formed of a non-magnetic, non-conductive material, and the inner rotor core is located within the winding retainer.

The housing includes openings formed on opposite sides, the winding retainer is cylindrical, and is installed to be concentric with the opening in the housing adjacent to one of the openings.

The outer rotor fixing plate is disc-shaped, and the outer rotor core is vertically formed along the edge of the outer rotor fixing plate.

The outer rotor core consists of a number of core pieces arranged in a cylindrical shape.

A fixing groove into which the outer rotor core is inserted is formed in the outer rotor fixing plate, and is located in the fixing groove, and includes a spring located outside the outer rotor core.

An outer rotor retainer is provided on the outer rotor fixing plate, and the outer rotor core is provided on the outer rotor retainer.

A fixing groove into which the outer rotor retainer is inserted is formed in the outer rotor fixing plate, and a spring located in the fixing groove and located outside the outer rotor retainer.

Since the permanent magnet synchronous motor according to the present invention is a double rotor type coreless type, it is possible to reduce the iron loss and improve the efficiency.

In addition, since the iron loss generated by the magnetic field due to the magnetic field can be reduced to close to zero, the efficiency can be improved, and since the heat generated by the iron loss is reduced, the burden of the cooling system can be reduced.

On the other hand, according to the present invention, as the rotational speed of the motor increases, the air gap increases and the electromotive force decreases, so that the effect of increasing the speed of the motor without using weak field control in the constant output driving section has a structure. have.

1 is a cross-sectional view of a permanent magnet synchronous motor according to an embodiment of the present invention.
Figure 2 is a plan view of the synchronous motor in the stopped state of the permanent magnet synchronous motor according to an embodiment of the present invention.
3 is a cross-sectional plan view of a synchronous motor in the case of an operating state of a permanent magnet synchronous motor according to an embodiment of the present invention.
4 is a cross-sectional view of a stator of a permanent magnet synchronous motor according to an embodiment of the present invention.
5 is a detailed combined plan view of a winding retainer and a winding of a stator of a permanent magnet synchronous motor according to an embodiment of the present invention.
Figure 6 is a cross-sectional view of the coupling of the rotor of the permanent magnet synchronous motor according to an embodiment of the present invention.
7 is a flowchart illustrating a process of manufacturing a permanent magnet synchronous motor according to an embodiment of the present invention.

Advantages and features of the present invention, and methods for achieving them will be clarified with reference to embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only the embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention pertains. It is provided to fully inform the holder of the scope of the invention, and the invention is only defined by the scope of the claims. Throughout the specification, the same reference numerals refer to the same components.

In describing embodiments of the present invention, when it is determined that a detailed description of known functions or configurations may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. In addition, terms to be described later are terms defined in consideration of functions in an embodiment of the present invention, which may vary according to a user's or operator's intention or practice. Therefore, the definition should be made based on the contents throughout this specification.

Hereinafter, a permanent magnet synchronous motor according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a combined cross-sectional view of a permanent magnet synchronous motor according to an embodiment of the present invention, Figure 2 is a plan view of the synchronous motor in the stopped state of a permanent magnet synchronous motor according to an embodiment of the present invention, Figure 3 is a present invention In the case of the operating state of the permanent magnet synchronous motor according to an embodiment of the present invention, a sectional view of the synchronous motor.

Meanwhile, FIG. 4 is a cross-sectional view of a stator of a permanent magnet synchronous motor according to an embodiment of the present invention, and FIG. 5 is a detailed plan view of a winding retainer and a winding of a stator of a permanent magnet synchronous motor according to an embodiment of the present invention, FIG. 6 is a combined cross-sectional view of the rotor of the permanent magnet synchronous motor according to an embodiment of the present invention.

1 to 6, the permanent magnet synchronous motor 100 according to an embodiment of the present invention is composed of a stator 200 and a rotor 300 coupled to the stator 200, and alternating current to the stator 200 When a rotating magnetic field is formed by applying, the rotor 300 rotates accordingly. At this time, the permanent magnet synchronous motor 100 may be used for a hybrid starter generator (HSG).

The stator 200 may be composed of a housing 210, a winding retainer 230 and a winding 250.

The housing 210 forms the outer shape of the permanent magnet synchronous motor 100, may be a box shape having an inner space 211, and the opposite sides of the housing 210 may be coupled by the rotor 300. The openings 212 and 213 are provided. At this time, the outer shape of the housing 210 may be variously formed, such as cylindrical, polygonal columnar.

The winding retainer 230 may be a cylindrical shape installed inside the housing 210 adjacent to one of the two openings 212 and 213 formed in the housing 210. At this time, the center of the winding retainer 230 is preferably installed to be concentric with the center of the opening (212, 213).

On the other hand, the winding 250 is located in the winding retainer 230, it is preferable that a space in which the winding 250 is installed in the winding retainer 230 so that the winding 250 can be stably fixed is preferably provided. .

Accordingly, a plurality of grooves are formed in the winding retainer 230, and the winding 250 is positioned in the plurality of grooves formed in the winding retainer 230.

For example, the winding retainer 230 may be formed of a cylindrical inner portion 231 and a plurality of extending portions 233 extending vertically from the inner portion 231. At this time, the extension portion 233 is preferably formed as a whole along the length of the inner portion 231, the winding 250 is positioned between the neighboring extension (233).

In addition, in order to prevent separation of the winding 250, the winding retainer 230 may further include a fixing part 235 extending vertically to both sides at the ends of the plurality of extension parts 233.

As described above, since the winding retainer 230 has a structure without a stator core, it is possible to perform winding work on the winding retainer 230.

The winding retainer 230 is provided to be fixed so that the winding 250 does not move by the magnetic force generated in the winding 250, and is fixed in the housing 210 so as to support the weight of the winding 250.

The winding retainer 230 is formed of a non-magnetic, non-conductive material so as not to affect magnetic flux flow, and may be formed of, for example, engineering plastic.

Therefore, the iron loss of the permanent magnet synchronous motor is mainly generated in the stator core, and the stator according to the present invention does not contain a magnetic material, so that the iron loss can be greatly reduced.

The rotor 300 includes a rotor shaft 310, an inner rotor core 320, a permanent magnet 330, an outer rotor fixing plate 340, a rotor rotor core 350 and a spring 360 And, the outer rotor retainer 370, the first and second bearings (380, 390) may be further included.

The rotor shaft 310 is provided to penetrate the stator 200, and at this time, it is provided to pass through the openings 212 and 213 of the housing 210 of the rotor 300.

The inner rotor core 320 is provided in the stator 200 in a form surrounding the rotor shaft 310, and the permanent magnet 330 is installed on the inner rotor core 320. At this time, the inner rotor core 320 is located in the winding retainer 230.

The permanent magnet 330 is preferably formed at a predetermined interval along the circumference of the inner rotor core 320.

The outer rotor fixing plate 340 is a disk shape coupled to the rotor shaft 310, and the outer rotor core 350 is provided at the edge of the outer rotor fixing plate 340.

At this time, the outer rotor core 350 is formed vertically along the edge of the outer rotor fixing plate 340, and is positioned to face the outside of the winding 250 of the stator 200.

The outer rotor core 350 shields the magnetic flux generated by the magnet and the winding from going outside, thereby preventing leakage of the magnetic flux and making a stable magnetic circuit.

At this time, the outer rotor core 350 may be formed in one cylindrical shape, but as in this embodiment, the outer rotor core 350 is adjacent to each other along the edge of the outer rotor fixing plate 340 It may be provided by a plurality of core pieces 351 forming a cylindrical shape.

That is, the outer rotor core 350 may be formed of a plurality of core pieces 351 arranged in a cylindrical shape.

3, when the outer rotor core 350 is composed of a plurality of divided core pieces 351, as the rotor 300 rotates, the plurality of core pieces 351 are subjected to centrifugal force. By tilting outward, the air gap α between the outer rotor core 350 and the winding 250 of the stator 200 increases, and the amount of magnetic flux interlinked to the winding 250 by increasing the air gap α. Over electromotive force decreases.

Table 1 below shows the electromotive force according to the increase in the air gap.

Void (α) Increment (mm) Electromotive force (V) 0 16.77 One 15.78 2 15.05 3 14.48 4 14.01 5 13.62

As can be seen from Table 1, as the air gap α between the outer rotor core 350 and the winding 250 of the stator 200 increases, the electromotive force decreases, so that the air gap α increases by 5 mm. In this case, the electromotive force is reduced by 18.78%. Therefore, as the rotational speed of the rotor 300 increases, the air gap between the outer rotor core 350 and the winding 250 of the stator 200 increases and the electromotive force decreases. , Without using the weak field control in the constant output operation section, it is possible to increase the speed of the rotor 300. Here, since the rotation speed of the rotor 300 means the rotation speed of the motor, the constant output operation It is possible to increase the speed of the motor without using the weak field control in the section.

* On the other hand, the outer rotor fixing plate 340 is formed with a fixing groove (not shown) for fixing the outer rotor core 350, the outer rotor core 350 may be inserted into the fixing groove and fixed. have.

At this time, the outer rotor core 350 may be provided directly on the outer rotor fixing plate 340, but the outer rotor retainer 370 is provided on the outer rotor fixing plate 340 as in the embodiment of the present invention. The outer rotor retainer 370 may have a structure in which the outer rotor fixing plate 340 is provided.

Meanwhile, the spring 360 is provided outside the outer rotor core 350 on the outer rotor fixing plate 340.

At this time, when a fixing groove is formed in the outer rotor fixing plate 340 as in the present embodiment, it is preferable that the spring is also inserted into the fixing groove together with the outer rotor core 350.

The spring 360 is configured to return the outer rotor core 350 inclined by centrifugal force to its original state, and may be, for example, a ring spring or a leaf spring.

That is, the spring 360 is compressed as the outer rotor core 350 is inclined by the centrifugal force, and then expands by the restoring force when the centrifugal force is reduced or does not occur, and the outer rotor core 350 is returned to its original state. Return to

On the other hand, when the outer rotor fixing plate 340 is provided on the outer rotor retainer 370 as in this embodiment, the spring located outside the outer rotor retainer 370 and the outer rotor retainer 370 ( 360) is located in the fixing groove.

The first and second bearings 380 and 390 are positioned between the rotor shaft 310 and the housing 210, and may be provided in a fixed shape on the rotor shaft 310.

As described above, the rotor according to the present invention is a structure capable of constructing a stable magnetic circuit with only the rotor without a stator core, and since the outer rotor and the inner rotor rotate at the same speed, changes in the magnetic field by the magnet in the outer and inner cores Since it does not occur, iron loss generated in the core can be removed.

Hereinafter, a process of manufacturing a permanent magnet synchronous motor according to an embodiment of the present invention will be briefly described.

7 is a flowchart illustrating a process of manufacturing a permanent magnet synchronous motor according to an embodiment of the present invention.

The permanent magnet synchronous motor according to an embodiment of the present invention can be manufactured by manufacturing a rotor assembly and a stator assembly, respectively, and then combining the rotor assembly with a stator assembly.

Referring to FIG. 7, the rotor assembly is manufactured by inserting a permanent magnet by manufacturing an inner rotor core (S710), connecting the inner rotor core and the rotor shaft (S720), and fixing the outer rotor core and outer rotor plate It can be manufactured by manufacturing and fixing to the rotor shaft (S730), and attaching bearings to both ends of the rotor shaft (S740).

On the other hand, the stator assembly may be manufactured through a process of manufacturing a winding retainer (S750), winding the retainer (S760), manufacturing the housing (S770), and fixing the winding retainer to the housing (S780). .

By combining the rotor assembly and the stator assembly thus manufactured (S790), the permanent magnet synchronous motor of the present invention can be manufactured.

On the other hand, although the permanent magnet synchronous motor according to the present invention has been described in accordance with an embodiment, the scope of the present invention is not limited to a specific embodiment, and is within a range obvious to those skilled in the art in connection with the present invention. It can be implemented by changing, altering, and changing branches.

Therefore, the embodiments and the accompanying drawings described in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments and the accompanying drawings. . The scope of protection of the present invention should be interpreted by the claims, and all technical spirits within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

100: permanent magnet synchronous motor 200: stator
210: housing 230: winding retainer
250: winding 300: rotor
310: rotor shaft 320: inner rotor core
330: permanent magnet 340: outer rotor fixing plate
350: outer rotor core 360: spring
370: outer rotor retainer 380, 390: bearing

Claims (7)

A stator installed in the housing and the housing, and composed of a winding retainer including a winding; And
A rotor composed of an inner rotor core having a permanent magnet installed therein and an outer rotor core connected to be rotated simultaneously with the rotor shaft outside the stator while being coupled to a rotor shaft passing through the housing inside the stator; Permanent magnet synchronous motor included. The method according to claim 1,
The rotor, the permanent magnet synchronous motor, characterized in that it includes a connecting portion that is connected to each other so that the rotor shaft and the outer rotor core rotate at the same time. The method according to claim 2,
The connecting portion is spaced apart from the inner rotor core at a predetermined distance, coupled to the rotor shaft, and a permanent magnet synchronous motor, characterized in that the outer rotor fixing plate integrally coupled to the outer rotor core. The method according to claim 3,
The outer rotor fixing plate is a disk shape, the outer rotor core is a permanent magnet synchronous motor, characterized in that formed vertically along the edge of the outer rotor fixing plate. The method according to claim 3,
A fixing groove into which the outer rotor core is inserted is formed in the outer rotor fixing plate,
Permanent magnet synchronous motor, characterized in that it comprises a spring located in the fixed groove, located on the outside of the outer rotor core. The method according to claim 3,
An outer rotor retainer is provided on the outer rotor fixing plate,
Permanent magnet synchronous motor, characterized in that the outer rotor core is provided on the outer rotor retainer. The method according to claim 1,
The outer rotor core is composed of a plurality of core pieces arranged in a cylindrical shape, the permanent magnet synchronous motor, characterized in that positioned to face the permanent magnet at a predetermined distance.

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