JP2012005327A - Resolver - Google Patents

Abstract

【Task】
To provide a resolver capable of reducing costs.
[Solution]
A resolver 1 that includes a rotor 2 and a stator 10 that includes a magnetic pole portion, and is arranged at a predetermined position in a resolver 1 in which the shape of the rotor 2 is determined so that the gap permeance of the magnetic pole portion changes in a sine wave shape as the rotor 2 rotates 1 magnetic pole part 11 and the 2nd magnetic pole part 12 arrange | positioned with respect to this 1st magnetic pole part 11 in the position corresponding to the phase change of 90 degree | times in the period change of gap permeance, and a phase change of 180 degree | times similarly It is comprised by the 3rd magnetic pole part 13 arrange | positioned in the position corresponding to. The exciting coil 20 for exciting the magnetic pole part is wound around the first magnetic pole part and the third magnetic pole part in the same direction with the same number of turns, and the second magnetic pole part has the exciting coil 20 of the first magnetic pole part. It is wound in the same number of turns in the opposite direction to the winding. The output coil 30 is wound around the first magnetic pole part, the second magnetic pole part, and the third magnetic pole part with the same number of turns in the same direction.

[Selection] Figure 1

Description

  The present invention relates to a resolver used for detecting a rotational position of a rotating shaft of a motor.

  As a conventional resolver, 4 × k magnetic pole portions (where k is an integer equal to or greater than 1) are provided in an angular range of 360 ° / n (n is an integer equal to or greater than 2) in mechanical angle (360 ° in electrical angle). Each magnetic pole part has an exciting winding (excitation coil) for exciting a plurality of magnetic pole parts alternately in different polarities, and every other magnetic pole part has a winding direction alternately. A plurality of detection winding portions formed by winding the winding conductors so as to be different from each other are alternately connected to the first detection winding portion configured in series and the remaining magnetic pole portions. Winding (winding) a second detection winding formed by connecting a plurality of detection winding sections formed by winding a winding conductor so that the winding directions are different from each other in series An nX reluctance resolver is disclosed (see, for example, Patent Document 1).

  Patent Document 2 describes a configuration similar to that described above using four magnetic poles as a conventional resolver (angle detector) (see, for example, FIG. 3 of Patent Document 2).

Japanese Patent Laid-Open No. 2002-168652 JP-A-8-178611

  In Patent Document 1 and Patent Document 2, the output from the detection winding (output coil) of one magnetic pole is an amplitude-modulated carrier wave (excitation voltage excited in the excitation coil), but the amplitude is zero. Never become. That is, the output V from the output coil is represented by the following equation.

V = (K + a · sinθ) · sinωt
θ is an electrical angle converted rotor angle (θ = n × mechanical angle), ω is an excitation frequency, t is time, K is a transformation ratio indicating the median value of the amplitude of the carrier wave, and a is the rotation of the rotor. V is the amount of change from K.

Here, every other output coil that is 180 degrees out of phase in electrical angle is connected in reverse, and the amplitude offset: K is set to zero. That is, if each magnetic pole part (phase is shifted by 90 degrees in electrical angle) is numbered in order and m = 1, 2, 3... And the output at the magnetic pole part m is expressed as V _Cm , VC ₁ And _VC3 are
V _C1 = (K + a · cosθ) · sinωt
V _C3 = (K + a · cos (θ + π)) · (−sinωt) = − (K−a · cosθ) · sinωt
It is expressed.

  Here, since the output coil wound around the magnetic pole part m = 3 is reversely wound with the output coil of the magnetic pole part m = 1, two output coils wound around the magnetic pole part m = 1 and m = 3 are provided. The output V1 from both ends of the two detection windings when connected in series can be a signal in which K is canceled as follows and the envelope of the output V1 changes with sin θ.

V1 = V _C1 + V _C3 = 2a · sinθ · sinωt
In order to obtain an angle signal, an output whose amplitude changes with cos θ is further required. An output coil wound around (m = 2, 4) is required. That is, as above,
V _C2 = (K + a · cos (θ + π / 2)) · sinωt = (K−a · sinθ) · sinωt
V _C4 = (K + a · cos (θ + 3 · π / 2)) · (−sinωt) = − (K + a · sinθ) · sinωt
V2 = V _C2 + V _C4 = −2a · cos θ · sin ωt
Is obtained. Accordingly, sin θ and cos θ are obtained, θ can be calculated, and the rotor rotation angle (mechanical angle) can be obtained.

  Thus, when the movement of the electrical angle with respect to the mechanical angle is 1 (1X), at least four magnetic poles, excitation coils, and output coils are required as described above. In the case of n times (nX), 4n magnetic poles, excitation coils, and output coils are required.

  An object of this invention is to provide the resolver which can reduce cost.

  A first problem-solving means that solves the above-described problem includes a rotor that rotates about a rotation axis, and a stator that is disposed around the rotor and has a plurality of magnetic pole portions, and the magnetic pole portion includes the magnetic pole portion. In a resolver in which an excitation coil and an output coil for exciting a part are wound, and the shape of the rotor is determined such that the gap permeance of the magnetic pole part periodically changes in a sine wave shape as the rotor rotates. The first magnetic pole portion arranged at a predetermined position, and a second magnetic pole portion arranged at a position corresponding to a phase change of 90 degrees in the period change of the gap permeance with respect to the first magnetic pole portion. A magnetic pole part, and a third magnetic pole part disposed at a position corresponding to a phase change of 180 degrees in a period change of the gap permeance with respect to the first magnetic pole part, The magnetic coil is wound around the first magnetic pole part and the third magnetic pole part in the same direction, and the second magnetic pole part is wound around the excitation coil of the first magnetic pole part. The output coil is wound around the first magnetic pole part, the second magnetic pole part and the third magnetic pole part in the same direction.

  The second problem-solving means for solving the above-described problem is that the exciting coil is wound around the first magnetic pole part, the second magnetic pole part, and the third magnetic pole part with the same number of turns or substantially the same number of turns. The output coil is wound around the first magnetic pole part, the second magnetic pole part, and the third magnetic pole part with the same or substantially the same number of turns.

  A third problem-solving means for solving the above-mentioned problem is that an output coil wound around the first magnetic pole part and an output coil wound around the second magnetic pole part are connected in series, and the series The configuration is such that signals at both ends of the output coil wound around the connected first magnetic pole part and the output coil wound around the second magnetic pole part are detected.

  According to a fourth means for solving the above problem, an output coil wound around the second magnetic pole part and an output coil wound around the third magnetic pole part are connected in series, and the series The configuration is such that signals at both ends of the output coil wound around the connected second magnetic pole part and the output coil wound around the third magnetic pole part are detected.

  A fifth problem-solving means for solving the above-described problem is that an exciting coil wound around the first magnetic pole part, an exciting coil wound around the second magnetic pole part, and a winding wound around the third magnetic pole part. The exciting coil to be operated is connected in series.

  A sixth problem-solving means for solving the above-described problem includes a rotor that rotates about a rotation axis, and a stator that is disposed around the rotor and has a plurality of magnetic pole portions, and the magnetic pole portion includes the magnetic pole portion. In a resolver in which an excitation coil and an output coil for exciting a portion are wound, and the shape of the rotor is determined so that the gap permeance of the magnetic pole portion periodically changes in a sine wave shape as the rotor rotates. The magnetic pole part is at least a first magnetic pole part arranged at a predetermined position, and a second magnetic pole part arranged at a position corresponding to a phase change of 90 degrees in the period change of the gap permeance with respect to the first magnetic pole part. And a third magnetic pole portion disposed at a position corresponding to a phase change of 180 degrees in the period change of the gap permeance with respect to the first magnetic pole portion, The excitation coil is wound around the first magnetic pole part, the second magnetic pole part, and the third magnetic pole part in the same direction, and the output coil includes the first magnetic pole part and the third magnetic pole part. It is wound around the magnetic pole part with the same number of turns, and the second magnetic pole part is wound in the opposite direction to the winding of the exciting coil of the first magnetic pole part.

  A seventh problem solving means for solving the above problem is that the exciting coil is wound around the first magnetic pole part, the second magnetic pole part and the third magnetic pole part with the same number of turns or substantially the same number of turns. The output coil is wound around the first magnetic pole part, the second magnetic pole part, and the third magnetic pole part with the same or substantially the same number of turns.

  According to the first to third, sixth, and seventh problem solving means, it is possible to reduce the necessary minimum number from four to three in at least one of the conventional magnetic pole portion, exciting coil, and output coil. Further, when the mechanical angle is 360 ° / n, that is, n times (axial multiplication angle nX), the number is reduced to 3n in at least one of the magnetic pole part, the excitation coil, and the output coil, which required 4n. be able to. Since at least one of the exciting coil and the output coil is not required to be wound, the tact time for winding the coil can be shortened.

  According to the fourth and fifth problem solving means, since a desired signal can be directly detected, a resolver capable of further reducing the cost can be obtained.

It is explanatory drawing which looked at the resolver in embodiment of this invention from the front. It is explanatory drawing explaining winding of an exciting coil and an output coil. It is an example of the waveform which generate | occur | produces in an output coil. It is explanatory drawing which looked at the resolver in another embodiment from the front.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows the overall configuration of a resolver 1 according to an embodiment of the present invention. The resolver 1 in this embodiment is a case of 1X (n = 1) in an nX variable reluctance resolver (VR type resolver) (mechanical angle = electrical angle).

  A rotor 2 made of a magnetic material, which will be described later, rotates in the center of the resolver 1 shown in FIG. 1, and a stator 10 made of the same magnetic material is disposed around the rotor 2. The stator 10 is provided with three magnetic pole portions (a first magnetic pole portion 11, a second magnetic pole portion 12, and a third magnetic pole portion 13) that protrude toward the rotation center of the rotor 2 described later. The opposing surface of the magnetic pole portion on the rotor 2 side is formed to be an arc centered on the rotation center of the rotor 2.

  Although details will be described later, each magnetic pole portion includes an exciting coil 20 (first exciting coil 21, second exciting coil 22, third exciting coil 23) and output coil 30 (first output coil 31, second exciting coil). The output coil 32 and the third output coil 33) are wound. At this time, the exciting coil 20 and the output coil 30 are wound around each magnetic pole portion via, for example, an insulator bobbin.

  The outer dimensions of the rotor 2 are designed so that the change in the circumferential direction of the gap permeance changes in a sine wave shape at each magnetic pole portion as the rotor 2 rotates. In the present embodiment, since it is 1 ×, the change of the gap permeance with respect to the circumferential position changes in one cycle for one rotation of the rotor 2 at the mechanical angle.

  The three magnetic pole portions (the first magnetic pole portion 11, the second magnetic pole portion 12, and the third magnetic pole portion 13) are provided at positions shifted from each other by 90 degrees in electrical angle in the circumferential direction. Specifically, as shown in FIG. 1, the first magnetic pole part 11 is located at the electrical angle of 0 degree, the second magnetic pole part 12 is located at the 90 degree position, and the third magnetic pole part 13 is located at the 180 degree position. Be placed. In other words, the three magnetic pole portions are arranged every 90 degrees from the 0 degree position in the periodic change phase 0 to 180 degrees of the gap permeance generated with the rotation of the rotor 2. Three magnetic pole portions are arranged in such a phase relationship, and the first magnetic pole portion 11 and the third magnetic pole portion 13 are arranged adjacent to the second magnetic pole portion 12.

  The exciting coil 20 is wound around each magnetic pole part with the same number of turns (may be substantially the same number of turns). The first exciting coil 21, the second exciting coil 22, and the third exciting coil 23 shown in FIG. 1 are wound around the first magnetic pole part 11, the second magnetic pole part 12, and the third magnetic pole part 13, respectively. It is the exciting coil 20 to be performed.

  The winding direction and connection of the first exciting coil 21, the second exciting coil 22, and the third exciting coil 23 in the present embodiment, and the first output coil 31, the second output coil 32, and the third The winding direction and connection of the output coil 33 are shown in FIG.

  As shown in FIG. 2, the first exciting coil 21, the second exciting coil 22, and the third exciting coil 23 are connected in series.

  Here, the second exciting coil 22 is wound in a direction opposite to the winding direction of the first exciting coil 21 and the third exciting coil 23. This is because the magnetic direction of the second magnetic pole portion 12 is changed with respect to the magnetic directions of the first magnetic pole portion 11 and the third magnetic pole portion 13 adjacent to the second magnetic pole portion 12.

  The output coil 30 is wound in the same direction in the same number of turns (may be substantially the same number of turns) in each magnetic pole part. The first output coil 31, the second output coil 32, and the third output coil 33 shown in FIG. 1 are wound around the first magnetic pole part 11, the second magnetic pole part 12, and the third magnetic pole part 13, respectively. Output coil 30.

  Note that the number of turns of the exciting coil 20 and the number of turns of the output coil 30 may be the same or different.

  As shown in FIG. 2, in this embodiment, the first output coil 31 and the second output coil 32 are connected in series, and the second output coil 32 and the third output coil 33 are also connected in series. It is connected to the.

  Here, the output voltages generated at both ends of the first output coil 31, the second output coil 32, and the third output coil 33 change the amplitude of the excitation frequency into a sine wave shape due to the gap permeance change of the rotor 2. However, since the magnetic resistance does not become zero, the signal is offset in an alternating manner. FIG. 3 shows an example of the waveform of the output voltage generated at both ends of each output coil (the first output coil 31, the second output coil 32, and the third output coil 33).

  Next, calculation of the rotation angle of the rotor 2 will be described below.

The excitation voltage _VIN that excites the excitation coil is expressed by the following equation (1). Here, E is a voltage amplitude value of the excitation voltage.

A voltage V _C1 generated in the first output coil 31 by the excitation voltage _VIN is expressed by the following equation (2). Where θ is an electrical angle converted rotor rotation angle (θ = n × mechanical angle), ω is an excitation frequency, t is time, K is a transformation ratio indicating a median value of amplitude of a carrier wave, and a is This is the amount of change of V from K as the rotor rotates.

The voltage V _C2 generated in the second output coil 32 is expressed by the following equation 3 because the second exciting coil 22 is reversely wound.

The voltage V _C3 generated in the third output coil 33 is expressed by the following equation (4).

It becomes.

Here, as shown in FIG. 2, the voltage at both ends when the first output coil 31 and the second output coil 32 are connected in series is output as V _OUT1 . That is, V _OUT1 is the sum of Expression 2 and Expression 3, and is expressed by Expression 5 below.

Similarly, the voltage at both ends when the second output coil 32 and the third output coil 33 are connected in series is output as _VOUT2 . That is, V _OUT2 is the sum of Equation 3 and Equation 4, and is represented by Equation 6 below.

V _OUT1 and V _OUT2 are the same as the output signals of the conventional resolver except that the phase is shifted by π / 4, and the rotation angle (mechanical angle) of the rotor 2 can be calculated. That is, since (θ + π / 4) is obtained from the output signals of V _OUT1 and V _OUT2 in the same manner as in the prior art, θ can be obtained by subtracting (π / 4) from the obtained (θ + π / 4). It becomes possible. From another viewpoint, since π / 4 is always added to θ, the coordinate origin may be set at a position (−π / 4).

  By configuring as in the present embodiment, it is possible to output signals for calculating the rotation angle of the rotor 2 as in the prior art, and from the required minimum number of the conventional magnetic pole portion, excitation coil, and output coil from four. It can be reduced to 3. In other words, in this embodiment, it is possible to eliminate the magnetic pole portion, the excitation coil, and the output coil corresponding to the electrical angle of 270 °.

  The present invention is not limited to the above-described embodiment, and various modifications are possible. Examples of such modifications (different embodiments) will be described below.

  (1) In the above-described embodiment, the case of 1X that generates an electrical angle that is 1 times the mechanical angle is used, but the case of nX that generates an electrical angle that is n times (electrical angle = n × mechanical angle) is also the same. An angle obtained by dividing the mechanical angle of 360 degrees into n is regarded as an electrical angle of 360 degrees, and three magnetic pole portions may be formed at positions of 0 degrees, 90 degrees, and 180 degrees in electrical angle.

  That is, in the case of nX, if i = 1, 2 ·· n, z = 1, 2, 3 and the magnetic pole portion is arranged at an angular position of (z / 4) (360 · i / n) in mechanical angle. Good. As can be seen from this, in the resolver according to the present invention in the case of nX, the total number of necessary magnetic pole portions is 3 × n.

  In order to describe this modification, for example, the configuration of the resolver 1 when the electrical angle is twice (n = 2) with respect to the mechanical angle is shown in FIG. 4 (the rotor is not shown). In this case, the total number of magnetic pole portions is 3 × 2 = 6, and the arrangement is 0 degrees, 45 degrees, 90 degrees, 180 degrees, 225 degrees, and 270 degrees in mechanical angles, and the magnetic pole sections 111 to 116 in FIG. Corresponding to Note that the exciting coils 121 to 126 and the output coils 131 to 136 in FIG. 4 are wound around the magnetic pole portions 111 to 116, respectively. Here, the winding directions of the exciting coils 121 to 126 are as follows. First, the winding direction of the exciting coil 121 and the exciting coil 123 is the same direction, and the winding direction of the exciting coil 122 is opposite to the winding direction of the exciting coil 121 and the exciting coil 123. Similarly, the winding direction of the excitation coil 124 and the excitation coil 126 is the same direction, and the winding direction of the excitation coil 125 is opposite to the winding direction of the excitation coil 124 and the excitation coil 126.

  In the present modification, the number of magnetic pole portions, excitation coils, and output coils that are required for 4n can be reduced to 3n. Therefore, cost can be reduced. Further, since the winding of the excitation coil and the output coil is not required, the tact time for coil winding can be shortened.

(2) In the above embodiment, the voltage values at both ends of the two output coils connected in series are detected in the detection of V _OUT1 and V _OUT2 , but the present invention is not limited to this. After detection, the detected values may be subjected to arithmetic processing such as addition. In this case, the output coils may not be connected in series.

  (3) Although the first excitation coil 21, the second excitation coil 22, and the third excitation coil 23 are connected in series in the above embodiment, the present invention is not limited to this. For example, in the case where the first exciting coil 21, the second exciting coil 22, and the third exciting coil 23 are configured not to be connected in series, and an exciting voltage can be applied to each, as in the present embodiment. Similar to the excitation voltages generated in the first excitation coil 21, the second excitation coil 22, and the third excitation coil 23 when connected in series, the first excitation coil 21, the second excitation coil 22, the second excitation coil 22, and the like. The excitation voltage may be generated in the three excitation coils 23.

  (4) In the above-described embodiment, the magnetic pole portion at the 270 degree position, the exciting coil, and the output coil at the electrical angle of 360 degrees are not included. However, any of the electrical angles of 0 degree, 90 degrees, 180 degrees, and 270 degree positions is used. Of course, it is possible to employ a configuration without such a single magnetic pole part, excitation coil, and output coil.

  (5) In the above embodiment, the stator 10 has a configuration in which the magnetic pole portion at a specific position (electrical angle 270 °) is not formed. However, the present invention is not limited to this. In this case, the magnetic pole portion at the position of 270 degrees is formed, but either or both of the exciting coil 20 and the output coil 30 may not be wound around the magnetic pole portion. Such a configuration eliminates the need for an excitation coil or output coil at an electrical angle of 270 degrees while using a conventional stator, thereby reducing costs. Further, since the winding of the excitation coil and the output coil is not required, the tact time for coil winding can be shortened.

  (6) In the above embodiment, the first output coil 31, the second output coil 32, and the third output coil 33 are wound in the same direction, and the first excitation coil 21 and the third excitation coil 23 are wound. The rotation direction is the same, the winding direction of the second excitation coil 22 is opposite to the winding direction of the first excitation coil 21 and the third excitation coil 23, and the output direction at the second magnetic pole portion is It is changing. However, the present invention is not limited to this, and in order to obtain the same result as in the above embodiment, the first exciting coil 21, the second exciting coil 22, and the third exciting coil 23 are wound in the same direction, The first output coil 31 and the third output coil 33 are wound in the same winding direction, and the second output coil 32 is wound with respect to the winding direction of the first output coil 31 and the third output coil 33. The direction may be reversed.

In addition, it is also possible to deform | transform combining the modification of (1)-(6) mentioned above.

DESCRIPTION OF SYMBOLS 1 Resolver 2 Rotor 10 Stator 11 1st magnetic pole part 12 2nd magnetic pole part 13 3rd magnetic pole part 20 Excitation coil 21 1st excitation coil 22 2nd excitation coil 23 3rd excitation coil 30 Output coil 31 1st 1 output coil 32 2nd output coil 33 3rd output coil

Claims (7)

A rotor that rotates about a rotation axis; and a stator that is disposed around the rotor and has a plurality of magnetic pole portions. An excitation coil that excites the magnetic pole portion and an output coil are wound around the magnetic pole portion. In the resolver in which the shape of the rotor is determined so that the gap permeance of the magnetic pole portion periodically changes in a sine wave shape with the rotation of the rotor,
The plurality of magnetic pole portions are arranged at least at positions corresponding to a first magnetic pole portion arranged at a predetermined position and a phase change of 90 degrees in a period change of the gap permeance with respect to the first magnetic pole portion. A second magnetic pole part, and a third magnetic pole part arranged at a position corresponding to a phase change of 180 degrees in a period change of the gap permeance with respect to the first magnetic pole part,
The exciting coil is wound around the first magnetic pole part and the third magnetic pole part in the same direction, and the second magnetic pole part is wound around the exciting coil of the first magnetic pole part. On the other hand, it is wound in the opposite direction
The output coil is a resolver wound around the first magnetic pole part, the second magnetic pole part, and the third magnetic pole part in the same direction. The exciting coil is wound around the first magnetic pole part, the second magnetic pole part and the third magnetic pole part with the same number of turns or substantially the same number of turns.
2. The resolver according to claim 1, wherein the output coil is wound around the first magnetic pole part, the second magnetic pole part, and the third magnetic pole part with the same or substantially the same number of turns.   The output coil wound around the first magnetic pole part and the output coil wound around the second magnetic pole part are connected in series and wound around the first magnetic pole part connected in series. The resolver according to claim 1, wherein the resolver is configured to detect signals at both ends of the output coil and the output coil wound around the second magnetic pole portion.   The output coil wound around the second magnetic pole part and the output coil wound around the third magnetic pole part are connected in series and wound around the second magnetic pole part connected in series. The resolver according to claim 3, wherein the resolver is configured to detect signals at both ends of the output coil and the output coil wound around the third magnetic pole portion.   An excitation coil wound around the first magnetic pole part, an excitation coil wound around the second magnetic pole part, and an excitation coil wound around the third magnetic pole part are connected in series. Item 5. A resolver according to any one of Items 1 to 4. A rotor that rotates about a rotation axis; and a stator that is disposed around the rotor and has a plurality of magnetic pole portions. An excitation coil that excites the magnetic pole portion and an output coil are wound around the magnetic pole portion. In the resolver in which the shape of the rotor is determined so that the gap permeance of the magnetic pole portion periodically changes in a sine wave shape with the rotation of the rotor,
The plurality of magnetic pole portions are arranged at least at positions corresponding to a first magnetic pole portion arranged at a predetermined position and a phase change of 90 degrees in a period change of the gap permeance with respect to the first magnetic pole portion. A second magnetic pole part, and a third magnetic pole part arranged at a position corresponding to a phase change of 180 degrees in a period change of the gap permeance with respect to the first magnetic pole part,
The exciting coil is wound around the first magnetic pole part, the second magnetic pole part and the third magnetic pole part in the same direction,
The output coil is wound around the first magnetic pole part and the third magnetic pole part with the same number of turns, and the second magnetic pole part is wound around the exciting coil of the first magnetic pole part. A resolver wound in the opposite direction. The exciting coil is wound around the first magnetic pole part, the second magnetic pole part and the third magnetic pole part with the same number of turns or substantially the same number of turns.
The resolver according to claim 6, wherein the output coil is wound around the first magnetic pole part, the second magnetic pole part, and the third magnetic pole part with the same or substantially the same number of turns.

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