JP2023047894A - Resolver stator structure and resolver - Google Patents

Abstract

To provide a resolver stator structure capable of suppressing reduction in the angle detection accuracy of a resolver and a resolver.SOLUTION: The stator structure includes a stator core and a stator winding. The stator core has an annular-shaped body and a plurality of teeth extending inwardly in the radial direction from a peripheral part of the body and arranged at an equal pitch along the circumferential direction. The stator winding is wound around the teeth. The body is provided with a plurality of long through-holes arranged at equal intervals along the circumferential direction and a plurality of arc-shaped gaps along the circumferential direction between the long through-holes and the root of the teeth. A bridging portion is formed between the neighboring arc-shaped gaps.SELECTED DRAWING: Figure 1

Description

The present invention relates to a resolver stator structure and a resolver.

Conventionally, a resolver is known as a sensor for detecting the rotation angle of rotating electric machines such as motors and generators.

Such a resolver includes, for example, a stator core provided with a plurality of teeth extending from the inner peripheral side of an annularly formed main body toward the center, and a rotor disposed inside the stator core. is attached to the shaft of the rotating electric machine. Stator windings are wound around the teeth via insulators, and the stator windings consist of excitation windings supplied with an excitation voltage and output windings that output two-phase signals according to the rotational angle of the rotor. It consists of

When a current flows through the windings of the rotating electrical machine, which is the target of the resolver's rotation angle detection, the leakage magnetic flux from the windings of the rotating electrical machine and the magnetic flux from the permanent magnets of the rotor of the rotating electrical machine will flow into the mounting part of the stator structure of the resolver. Alternatively, a bolt or the like inserted through the mounting portion may act as an antenna, enter the inner region of the stator structure of the resolver, and interlink with the stator windings of the resolver. When the magnetic flux from the rotating electric machine interlinks with the stator winding of the resolver, it may be superimposed as a noise component on the waveform of the signal output from the output winding of the stator winding, and the angle detection accuracy of the resolver may deteriorate.

In order to solve this problem, conventionally, the magnetic flux entering from the outer peripheral side to the inner peripheral side of the stator structure is reduced in variation in the effect on the windings wound around the teeth, and the angle caused by the external magnetic flux is reduced. A resolver stator structure capable of suppressing deterioration in detection accuracy has been proposed (see, for example, Patent Document 1).

JP 2019-126241 A

However, the conventional stator structure is designed to reduce the variation in the influence of the external magnetic flux entering from the outer circumference side to the inner circumference side of the stator core on the stator windings wound around the teeth. Part of the external magnetic flux enters the inner circumference, and at places where the flow of the excitation magnetic flux generated by the stator windings wound around the teeth is disturbed, part of the external magnetic flux that has penetrated inside the stator core is disturbed. Therefore, there is room for improvement in suppressing deterioration in angle detection accuracy of the resolver.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a resolver stator structure and a resolver capable of suppressing deterioration in angle detection accuracy of the resolver.

To solve the above-described problems and achieve the object, a stator structure according to one aspect of the present invention includes a stator core and stator windings. The stator core has an annular main body portion and a plurality of teeth extending radially inward from the peripheral edge of the main body portion and arranged at equal pitches along the circumferential direction. The stator winding is wound around the teeth. The main body includes a plurality of elongated through holes arranged at equal intervals along the circumferential direction, and a region between the elongated through holes and the roots of the teeth along the circumferential direction. and a plurality of arcuate voids. A bridging portion is formed between the adjacent arcuate gaps.

A stator structure according to an aspect of the present invention can suppress deterioration in angle detection accuracy of a resolver.

FIG. 1 is a plan view of a resolver according to one embodiment. FIG. 2 is a partially enlarged view of the stator core. FIG. 3 is a diagram showing an example of the details of the shape of the arcuate gap of the stator core. FIG. 4 is a partially enlarged view showing an example of external magnetic flux flow in a resolver. FIG. 5 is a partially enlarged view showing an example of the flow of exciting magnetic flux in a resolver. FIG. 6 is a plan view of a resolver of a first comparative example (Patent Document 1). FIG. 7 is a partially enlarged view showing an example of external magnetic flux flow in a resolver of a second comparative example obtained by modifying the first comparative example. FIG. 8 is a partially enlarged view showing an example of the flow of excitation magnetic flux in the resolver of the second comparative example.

A stator structure of a resolver and a resolver according to embodiments will be described below with reference to the drawings. In addition, this invention is not limited by this embodiment. In addition, the dimensional relationship of each element in the drawings, the ratio of each element, and the like may differ from reality. Even between the drawings, there are cases where portions with different dimensional relationships and ratios are included. In principle, the contents described in one embodiment and modification are similarly applied to other embodiments and modifications.

FIG. 1 is a plan view of a resolver 1 according to one embodiment. FIG. 2 is a partially enlarged view of the stator core 3, which is a component of the resolver 1. FIG. 2, the stator windings 5 are shown in cross section. 1 and 2, the resolver 1 has a stator 2 and a rotor 8. As shown in FIG.

(stator structure)
The stator 2 includes a stator core 3, a stator winding 5 wound around teeth 3b of the stator core 3 via an insulator 4, and a terminal block 6 having terminal pins 7 to which terminals of the stator winding 5 are connected. I have.

The stator core 3 is configured by laminating a plurality of flat cores made of electromagnetic steel sheets in the axial direction. The stator core 3 is formed with an annular main body portion 3a and a plurality of (14 in the figure) teeth 3b extending radially inward from the inner peripheral edge of the main body portion 3a. A plurality of elongated through holes 3d having the same shape are formed in the annular main body 3a at regular intervals along the circumferential direction. It is formed on the circumference of a circle whose center coincides with the rotation center 8a of the rotor 8.

The elongated through hole 3d is used as a hole for inserting a bolt for fixing the stator core 3 of the stator 2 to a housing (not shown). A plurality of notches 3c are formed in the outer peripheral edge of the annular body portion 3a. This notch 3c engages with a positioning pin and is used for positioning the stator core 3 when the stator 2 is fixed to the housing.

A stator winding 5 is wound around each tooth 3b of the stator core 3 with an insulator 4 interposed therebetween. The stator winding 5 consists of an excitation winding and an output winding. The output winding outputs a two-phase output signal, and consists of a cos-phase winding and a sine-phase winding. The ends of the end wires 5a of the stator windings 5 are electrically connected by being tied to predetermined terminal pins 7 arranged on a terminal block 6. As shown in FIG. The insulator 4 is formed integrally with the stator core 3 by inserting the stator core 3, and the terminal block 6 is formed integrally with the insulator 4 at the same time as the insulator is molded.

A plurality of arcuate gaps 3f are formed along the circumferential direction between the root side of the teeth 3b and the elongated through holes 3d. A bridging portion 3h consisting of a slight gap is formed between adjacent arcuate gaps 3f.

(Rotor structure)
A rotor 8 that is coupled to the outer peripheral surface of a shaft 10 of a rotating electric machine (for example, a motor) and rotates around a rotation center 8 a includes a rotor core 9 . The rotor 8 is arranged inside the stator core 3 and constitutes an inner rotor type variable resolver.

The rotor core 9 is configured by laminating a plurality of flat cores made of electromagnetic steel sheets, and has a plurality of projections on the outer peripheral surface of the rotor core 9 . The illustrated rotor core 9 forms a shaft angle multiplier of 3X.

(Shape of arc-shaped gap)
FIG. 3 is a diagram showing a detailed example of the shape of the arcuate gap 3f of the stator core 3. As shown in FIG. The arcuate air gap 3f has an arcuate shape along a virtual circle C1 centered at the center 3k of the slot 3j formed between the adjacent teeth 3b of the stator core 3 and having a radius greater than or equal to the midpoint of the width of the teeth 3b. are doing. A virtual line L1 is a line passing through the midpoint of the width of the tooth 3b. Also, the center 3k of the slot 3j is arranged along a virtual circle C2 having the center of the stator core 3 as its center.

Since the arcuate gap 3f is formed between the slot 3j and the elongated through hole 3d, it is set to the extent that the core strength between the through hole 3d and the arcuate gap 3f can be maintained. . Moreover, the radial width of the arcuate gap 3f is not particularly limited as long as the arcuate gap 3f can function as a flux barrier.

The width of the bridge portion 3h formed between the adjacent arc-shaped air gaps 3f is set so as to provide a magnetic resistance that can suppress magnetic flux from entering the inner region of the stator core 3 from the outside.

(External magnetic flux flow, excitation magnetic flux flow)
FIG. 4 is a partial enlarged view showing an example of the flow of the external magnetic flux in the resolver 1 of the embodiment, and is a diagram obtained by magnetic field analysis of the state in which the leakage magnetic flux from the rotating electric machine flows into the resolver 1 by computer simulation. A curve shown in the stator core 3 represents the external magnetic flux. FIG. 5 is a partial enlarged view showing an example of the flow of the excitation magnetic flux in the resolver 1. A computer simulation shows the flow of the excitation magnetic flux generated when a predetermined voltage is applied to the excitation winding of the stator winding 5. FIG. 10 is a magnetic field analyzed diagram; The characteristics of the flow of the external magnetic flux and the flow of the excitation magnetic flux will be described later in comparison with a comparative example.

(Comparative example)
FIG. 6 is a plan view of a resolver 3' of a first comparative example (Patent Document 1). In FIG. 6, the stator structure 1' has an annular body portion 11' and a plurality of teeth 12' extending in the radial direction of the body portion 11' and arranged along the circumferential direction of the body portion 11'. It has a stator core 10'. The main body portion 11' is formed in an arc shape along the circumferential direction of the main body portion 11'. A plurality of holes 14' are arranged along the circumferential direction of the main body 11' between the plurality of teeth 12' and the plurality of elongated holes 13'. At least one of the holes 14' is arranged between the beam 15' provided between the adjacent long holes 13' and the tooth 12' adjacent to the beam 15'. ' are arranged at equal angular intervals along the circumferential direction of the body portion 11'.

In FIG. 6, reference numeral 2' denotes a rotor, reference numeral 2a' denotes a convex portion, reference numeral 20' denotes an insulator, reference numeral 30' denotes a winding, reference numeral 31' denotes a coil, reference numeral 40' denotes a terminal block portion, reference numeral 41' denotes a terminal, Reference numeral 41a' denotes a binding portion, reference numeral 42' denotes a guide portion, reference numeral 43' denotes an insertion hole, reference numeral 50' denotes a lead wire holding portion, reference numeral 51' denotes an insertion portion, and reference numeral 101' denotes an output shaft.

As a result, variations in the influence of leakage magnetic flux entering from the entire outer peripheral side of the teeth 12 ′ arranged along the entire inner periphery on the coils 31 ′ wound around the teeth 12 ′ are reduced.

FIG. 7 is a partially enlarged view showing an example of the flow of external magnetic flux in a resolver 1″ of a second comparative example that is a modification of the first comparative example. is a diagram obtained by magnetic field analysis by computer simulation. FIG. 8 is a partially enlarged view showing an example of the flow of the excitation magnetic flux in the resolver 1″ of the second comparative example. It is the figure which magnetic field analysis of the state where magnetic flux flows was carried out by the computer simulation. Since no notch is provided in the first comparative example of FIG. 6, a notch 3c″ is provided in the second comparative example for easy comparison with the embodiment. The antenna into which the magnetic flux enters is not limited to the notch, and the external magnetic flux enters even if there is no notch.

(Restriction of magnetic flux entering from the outer circumference of the stator structure to the inner circumference of the stator core)
In the outer peripheral region of the stator core 3 ″ of the resolver 1 ″ in the second comparative example of FIG. 7, elongated through holes 3 d ″ of the same shape are arranged at regular intervals along the circumferential direction. A notch 3c'' is arranged between the teeth 3b''. Circular through-holes 3g'' having the same shape are arranged at regular intervals along the circumferential direction in the outer region of the base of the teeth 3b''. Both the elongated through hole 3d'' and the circular through hole 3g'' act as a flux barrier.

As shown in FIG. 7, an external magnetic flux entering from the outside (rotating electric machine) using the corner of the notch 3c″ formed on the outer peripheral edge of the stator core 3″ of the resolver 1″ as an antenna is directed to the adjacent elongated hole. Part of the external magnetic flux that has entered the inner peripheral region of the stator core 3 ″ from between the through holes 3 d ″ passes between the circular through holes 3 g ″ and interlinks with the stator winding 5 ″ to return. do.

When part of the external magnetic flux entering the inner peripheral region of the stator core 3 ″ interlinks with the stator winding 5 ″, it is superimposed as a noise component on the waveform of the signal output from the output winding of the stator winding 5 ″, This is a factor in lowering the angle detection accuracy of the resolver 1″.

As described above, in the resolver 1″ of the second comparative example shown in FIG. 7, it is difficult to prevent the external magnetic flux entering from the outer peripheral region of the stator core 3″ from entering the inner peripheral region of the stator core 3″.

On the other hand, in the embodiment of FIG. 4, in the outer peripheral region of the stator core 3 of the resolver 1, elongated through holes 3d of the same shape are arranged at regular intervals along the circumferential direction. A notch 3c is arranged between the through holes 3d. In addition, a plurality of arcuate gaps 3f are formed at equal intervals along the circumferential direction in the region between the root side of the tooth 3b and the elongated through hole 3d. Both the elongated through hole 3d and the arcuate gap 3f act as a flux barrier. A slight gap is provided between the adjacent arc-shaped spaces 3f to form a bridging portion 3h.

In FIG. 4, the corner of the notch 3c formed on the outer peripheral edge of the stator core 3 of the resolver 1 is used as an antenna, and the external magnetic flux entering from the outside (rotating electric machine) is blocked by the stator core 3 by the arc-shaped air gap 3f acting as a flux barrier. is suppressed from entering the inner peripheral region and returns. In addition, a bridging portion 3h is formed between the adjacent arc-shaped air gaps 3f, but the width of the bridging portion 3h is a slight gap, so the external magnetic flux entering from the outer peripheral side of the stator core 3 is Entry into the inner peripheral region of the stator core 3 from the portion 3h is suppressed. In other words, due to the slight gap, the magnetic resistance of the bridge portion 3h is high, and the magnetic resistance of the magnetic path length through which the external magnetic flux returns is high, and the external magnetic flux cannot pass through the bridge portion 3h.

As a result, the external magnetic flux entering from the outer peripheral side of the stator core 3 is suppressed from entering the inner peripheral region of the stator core 3 and is suppressed from interlinking with the stator winding 5. Since noise components are not superimposed on the waveform of the signal output from the windings, there is no possibility that the angle detection accuracy of the resolver 1 is lowered.

(Regarding suppression of disturbance of the path of the excitation magnetic flux generated by the excitation winding)
In the outer peripheral region of the stator core 3 ″ of the resolver 1 ″ in the second comparative example of FIG. Notches 3c″ are arranged between the through holes 3d″ of the teeth 3b″. Circular through holes 3g″ of the same shape are arranged at equal intervals along the circumferential direction in the outer region of the base of the teeth 3b″. Both the elongated through hole 3d'' and the circular through hole 3g'' act as a flux barrier.

When a predetermined excitation voltage is applied to the excitation windings of the stator windings 5'' wound around the teeth 3b'', excitation magnetic flux is generated and magnetic poles are formed at both ends of the excitation windings (stator windings 5''). The excitation magnetic flux flows through the teeth 3b'', exits from one end of the excitation winding (stator winding 5''), and exits from the excitation winding (stator winding 5'') wound on the adjacent tooth 3b''. 5″). The other end of the excitation winding (stator winding 5″) flows into the excitation winding (stator winding 5″) wound on the adjacent tooth 3b″. The excitation magnetic flux coming out of the other end of the flows in.

A plurality of circular through holes 3g'' are formed in a region between the root side of the teeth 3b'' and the elongated through holes 3d'' and close to the inner peripheral side of the stator core 3''. are formed at regular intervals along the This region acts as a core-back portion that forms a main magnetic path for the excitation magnetic flux generated in the excitation winding. The flow of the exciting magnetic flux is hindered from flowing into the other tooth 3b'', and the flow of the exciting magnetic flux swells outward and becomes a factor of great disturbance. It does not flow and is greatly disturbed and bulges outward. When the excitation magnetic flux is greatly disturbed, the external magnetic flux entering the stator core 3″ from the outside is likely to be superimposed on the excitation magnetic flux, and as a result of the excitation magnetic flux being varied, the angular accuracy of the resolver 1″ may decrease.

In contrast, in the embodiment of FIG. 5, a plurality of arc-shaped spaces 3f are formed at equal intervals along the circumferential direction in the region between the root side of the teeth 3b and the elongated through-holes 3d. It is A bridging portion 3h having a slight gap is formed between adjacent arc-shaped spaces 3f. A region between the root side of the tooth 3b and the elongated through hole 3d serves as a core-back portion forming a main magnetic path of the excitation magnetic flux generated in the excitation winding.

When a predetermined excitation voltage is applied to the excitation windings of the stator windings 5 wound around the teeth 3b, excitation magnetic flux is generated and magnetic poles are formed at both ends of the excitation windings (stator windings 5). The excitation magnetic flux flows through the teeth 3b acting as the iron core of the coil, exits from one end of the excitation windings (stator windings 5), and exits from the excitation windings (stator windings 5) wound around the adjacent teeth 3b. It flows into one end of the winding 5). Further, the excitation magnetic flux emitted from the other end of the excitation winding (stator winding 5) wound around the adjacent teeth 3b flows into the other end of the excitation winding (stator winding 5).

The main part of the excitation magnetic flux flowing through the core back portion flows along the inner peripheral side of the stator core 3, but part of the excitation magnetic flux flows in a semicircular shape connecting the pitches of the teeth 3b. Therefore, in order not to disturb the flow of the excitation magnetic flux, the arc-shaped air gap 3f is formed in a shape along the excitation magnetic flux flowing in a semicircular shape. Since the path of the exciting magnetic flux is not blocked by the arc-shaped air gap 3f acting as a flux barrier, the exciting magnetic flux is not greatly disturbed. That is, the excitation magnetic flux flows along the arcuate air gap 3f in a neat semicircular shape, without being disturbed and bulging outward. As a result, external magnetic flux entering the stator core 3 from the outside is not superimposed on the exciting magnetic flux.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention.

As described above, the stator structure according to the embodiment has an annular main body portion and a plurality of teeth extending radially inward from the peripheral edge of the main body portion and arranged at equal pitches along the circumferential direction. A stator core and stator windings wound around teeth are provided. A plurality of arcuate gaps are formed along the circumferential direction in a region between the roots of the grooves, and bridging portions are formed between the adjacent arcuate gaps. As a result, deterioration in angle detection accuracy of the resolver can be suppressed.

Also, the arcuate gap is formed along a circle whose center is the center of the slot formed between the adjacent teeth and whose radius is a distance from this center equal to or greater than the midpoint of the width of the tooth. This makes it possible to further stabilize the flow of the excitation magnetic flux.

In addition, the bridging portion is arranged radially outside the teeth. As a result, the excitation magnetic flux is not hindered by the bridge portion.

Also, the stator winding is composed of an excitation winding and an output winding for two-phase output. Thereby, angle detection can be performed as a resolver.

It also comprises the stator structure described above and a rotor arranged inside the stator structure. Thereby, a resolver that detects an angle can be configured.

Moreover, the present invention is not limited by the above embodiments. The present invention also includes those configured by appropriately combining the respective constituent elements described above. Further effects and modifications can be easily derived by those skilled in the art. Therefore, broader aspects of the present invention are not limited to the above-described embodiments, and various modifications are possible.

Reference Signs List 1 resolver, 2 stator, 3 stator core, 3a main body, 3b tooth, 3c notch, 3d through hole, 3f gap, 3h bridging portion, 3j slot, 3k center, 4 insulator, 5 stator winding, 5a end wire, 6 terminal base, 7 terminal pin, 8 rotor, 8a center of rotation, 9 rotor core, 10 shaft

Claims (5)

a stator core having an annular main body portion, and a plurality of teeth extending radially inward from a peripheral edge of the main body portion and arranged at equal pitches along the circumferential direction;
and a stator winding wound around the teeth,
The main body includes a plurality of elongated through holes arranged at equal intervals along the circumferential direction, and a region between the elongated through holes and the roots of the teeth along the circumferential direction. having a plurality of arc-shaped voids,
A bridging portion is formed between the adjacent arcuate gaps,
Resolver stator structure. The arc-shaped gap is formed along a circle centered at the center of the slot formed between the adjacent teeth and having a radius equal to or greater than the midpoint of the width of the teeth from the center.
The stator structure of the resolver according to claim 1. The bridging portion is arranged radially outward of the teeth,
The resolver stator structure according to claim 1 or 2. The stator winding is composed of an excitation winding and an output winding that performs two-phase output,
A resolver stator structure according to any one of claims 1 to 3. a stator structure according to any one of claims 1 to 4;
a rotor positioned inside the stator structure;
resolver.

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