JP2607047B2 - Rotation angle detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation angle detection device provided with a single rotation detection resolver and a multipolar resolver.

[0002]

2. Description of the Related Art Conventionally, one direct drive motor
A rotation angle detection device that incorporates a rotation detection resolver and a multipolar resolver and detects the rotation angle of the output shaft of a motor with high resolution based on output data of two resolvers is used. The rotor of the one-rotation detection resolver is formed of a disk that is eccentrically supported by a shaft, and the amount of eccentricity is set to, for example, approximately 0.6 mm. An exciting salient pole is provided at a position facing the outer peripheral surface of the eccentric rotor. The rotor of the multipolar resolver is formed in a gear shape having, for example, 132 salient poles. Exciting salient poles are similarly provided at positions facing the outer peripheral surface of the multipolar rotor.

When the eccentric rotor is rotated in a state where the reference signal is input to the coil on the stator side of the one-rotation detection resolver, the rotation angle of the eccentric rotor from the coil, that is, the gap between the exciting salient pole and the eccentric rotor causes the rotation. Position is determined 3
A sine wave having one cycle of 60 ° is output. This sine wave is converted by a resolver-to-digital converter into linear output data as shown in FIG. Also, when the multi-pole rotor is rotated in a state where the reference signal is input to the coil on the stator side of the multi-pole resolver, the rotation angle of the multi-pole rotor, that is, each pole of the multi-pole rotor and the exciting salient pole are output from the coil. The rotation angle per pole whose position is determined by the positional relationship of
A sine wave having a period is output. The sine wave is converted into a plurality of linear output data corresponding to each pole as shown in FIG. 9 by a resolver-digital converter.
Note that each of the plural (132) straight lines is called a pole.

In this rotation angle detection device, correction data ΔAma and ΔBma for each output data Ama and Bma of a one-rotation detection resolver and a multipolar resolver are set in advance. Then, when the motor is used, the control computer informs the control computer of the position immediately before the start of the motor (hereinafter referred to as the initial position and represented by θK)
, The output data Ama and Bma of the one-rotation detection resolver and the multi-polar resolver are taken in. Note that this initial position θ
The output data Ama and Bma of the one-rotation detection resolver and the multipolar resolver at K are called initial position data, respectively.
Represented by K and BK.

The correction data ΔAma for the initial position data AK of the one-rotation detection resolver (this is referred to as ΔAma for convenience)
K). The initial position data AK is corrected by the correction data ΔAK. From the corrected initial position data (AK + ΔAK), the poles of the multipolar resolver for the initial position data AK (in this case, the poles at the initial position θK, The initial pole TBK is calculated. Absolute data Bak is calculated from the initial pole TBK and the initial position data BK of the multipolar resolver. Subsequently, the correction data ΔBma for the initial position data BK
(This is represented by ΔBK for convenience) is read. Then, the correction data ΔBK and the absolute data Bak
Is added, the rotational position data corresponding to the position immediately before the start of the motor, that is, the initial position θK (this is referred to as initial rotational position data to distinguish it from the others) is calculated.

When the output data Bma (t) of the first multipolar resolver is fetched after a predetermined time t has elapsed,
The output data Bma (t) is compared with the initial position data BK. Based on this comparison, the output data Bma at that time is
Identify the pole TBK (t) of the multipolar resolver for (t),
The absolute data Bak (t) is obtained from the newly specified pole TBK (t) and the output data Bma (t) at that time. Subsequently, the correction data ΔBma for the output data Bma (t) at that time is read. Then, by adding the correction data ΔBma and the absolute data Bak (t), the rotational position data after a lapse of a predetermined time t from the initial position θK of the motor is calculated.

Thereafter, every time a predetermined time elapses, the output data Bma of the multi-pole resolver is fetched, and the above-described calculation is performed to obtain the rotation angle θ of the motor, that is, the rotation position data. I have.

[0008]

When a radial external force acts on the rotating shaft of the motor during use, the center of the eccentric rotor is displaced from the center of the stator. Further, since the eccentric amount of the eccentric rotor is formed to be approximately 0.6 mm, the amount of change in the gap between the eccentric rotor and the exciting salient pole per one pole of the 132-pole multipole resolver is approximately 7 μm. If the external force becomes excessively large, the center of the eccentric rotor and the center of the stator may be shifted by more than 7 μm. As a result, the relationship of the gap between the eccentric rotor and the exciting salient pole with respect to the rotation angle of the eccentric rotor of the one-rotation detection resolver changes.
The relationship between the rotation angle of the eccentric rotor and the output data of the one-rotation detection resolver changes. On the other hand, in a multipolar resolver, even if the multipolar rotor is displaced from the stator, the relationship between the rotation angle of the multipolar rotor and the output data basically hardly changes. Accordingly, the relationship between the output data of the one-rotation detection resolver and the output data of the multipolar resolver with respect to the rotation position of the output shaft is shifted.

That is, as shown in FIG. 9, if the initial position data AK corresponding to the rotation angle θK is output from the one-rotation detection resolver in a state where no external force is applied to the output shaft of the motor, the initial position data AK From this, the initial pole TBK of the multipole resolver is specified. Then, rotation initial position data corresponding to the rotation angle θK is calculated from the initial pole TBK and the initial position data BK of the multipolar resolver.

However, when an external force is applied to the output shaft and the eccentric rotor is displaced from the stator, for example, as shown by a two-dot chain line in FIG. Output data AL corresponding to angle θL
Is output. As a result, the initial pole TBL of the multipolar resolver is specified by the output data AL. Further, the rotation angle θL is calculated from the initial pole TBL and the initial position data BK of the multipolar resolver. Therefore, a rotation angle θL different from the actual rotation angle θK is calculated as the initial position, and the rotation angles θ sequentially detected are all shifted values.

[0011] A similar problem is also caused by a change in environmental temperature. The present invention has been made to solve the above problems, and an object of the present invention is to suppress a rotation angle detection error generated as a result of applying an excessively large external force in a radial direction of an output shaft provided with a rotor. It is an object of the present invention to provide a rotation angle detecting device which can be used.

[0012]

In order to solve the above-mentioned problems, the invention according to claim 1 is a one-rotation detection resolver and a one-rotation detection resolver.
A rotation detection resolver, one or a plurality of first multipole resolvers having different numbers of poles from each other, a second multipole resolver having a larger number of poles than the first resolver, and an initial obtained from the one rotation detection resolver. First initial pole determining means for determining an initial pole of the first multipolar resolver with respect to the position data; and an initial position of the first multipolar resolver from the initial pole and initial position data obtained from the first multipolar resolver. First absolute data calculating means for obtaining absolute data obtained by converting data into absolute data, second initial pole determining means for determining an initial pole of a second multi-pole resolver for the absolute data, and the initial pole and a second multi pole. The absolute position data obtained by converting the initial position data into absolute data is obtained from the initial position data obtained from the pole resolver. A second absolute data calculating means for outputting as a data, and a multipole measurement obtained from a comparison result between the multipole measurement data of the second multipole resolver obtained sequentially and the multipole measurement data obtained before that. Pole assigning means for assigning the poles of the second multi-polar resolver to data, third absolute data calculating means for obtaining absolute data that has been converted from the assigned poles and the multi-pole measurement data, and outputting the data as rotational position data; Consists of

Further, in the invention according to claim 2, the exciting salient pole of the one-rotation detecting resolver and the exciting salient pole of the first multipolar resolver are provided on the same stator. According to a third aspect of the present invention, the first rotation setting data is generated for each one rotation setting data obtained from the one rotation detection resolver, and the one rotation setting data is obtained from the corresponding first multipolar resolver. One rotation correction data for correcting the multi-pole setting data;
Is generated for each first multi-pole setting data obtained from the multi-polar resolver, and the first multi-pole setting data is converted to the second multi-pole setting data obtained from the corresponding second multi-polar resolver. First multipolar correction data for correcting by
For each second multi-pole setting data obtained from the multi-pole resolver, and for correcting the second multi-pole setting data with respect to the reference data created for each corresponding rotational position. Storage means for storing second multi-polarity correction data; determining the one-rotation correction data corresponding to the initial position data; adding the one-rotation correction data to the initial position data; A first correction initial position data calculating means for obtaining data; a first multipolar correction data corresponding to the absolute data; a first multipolar resolver for adding the first multipolar correction data to the absolute data; A second correction initial position data calculating means for obtaining the correction initial position data of the first and second multi-pole correction data corresponding to the absolute data; Third correction initial position data calculating means for obtaining correction initial position data of the second multipolar resolver by adding the above multipolar correction data, and obtaining second multipolar correction data corresponding to the absolute data, Correction position data calculating means for adding the second multipolar correction data to obtain corrected initial position data of the second multipolar resolver, wherein the first initial pole determining means comprises:
An initial pole of a first multi-pole resolver is determined from the corrected initial position data obtained by the first corrected initial position data calculating means, and the second initial pole determining means is provided by the second corrected initial position data calculating means. Calculates the initial pole of the second multi-pole resolver from the corrected initial position data obtained by the above, and the third corrected initial position data calculating means outputs the calculated corrected initial position data as rotation initial position data, and outputs the corrected position data. The calculating means outputs the calculated corrected position data as rotational position data.

[0014]

Therefore, according to the first aspect of the present invention, the initial multipole resolver corresponding to the initial position has an initial pole whose number of poles is smaller than that of the second multipole resolver. It is specified by the absolute data obtained from the initial pole and initial position data. Then, rotation initial position data is calculated based on the absolute data obtained from the initial pole and the initial position data of the second multipolar resolver. As a result, even if the initial position data of the one-rotation detection resolver has an error with respect to the output data with respect to the actual initial position,
The initial pole of the multipole resolver is accurately determined. Therefore, since the initial pole of the second multipolar resolver is accurately determined, accurate rotation initial position data corresponding to the rotation position is calculated. Further, since the poles of the output data sequentially taken in by the rotation of the resolver are specified by the comparison result with the output data taken in front of the resolver, the poles of the second multipolar resolver for the output data are specified accurately. . As a result, the rotational position data corresponding to each output data is accurately calculated.

According to the second aspect of the present invention, the exciting salient pole of the one-rotation resolver and the exciting salient pole of the first multipolar resolver are provided on the same stator. The rotor of the first multipolar resolver can be located in close proximity. Also, the number of parts is reduced.

According to the third aspect of the present invention, one-rotation correction data corresponding to the first multi-pole setting data of one-rotation setting data, and one-rotation correction data corresponding to the second multi-pole setting data of the first multi-pole setting data Second multipolar correction data corresponding to the first multipolar correction data and the corresponding reference data of the second multipolar setting data is created and stored in advance. The first corresponding to the initial position
The initial pole of the multi-polar resolver is determined from the corrected initial position data obtained by correcting the initial position data of the one-rotation detection resolver with the one-rotation correction data. Next, the initial position data of the first multipolar resolver is made absolute based on the initial pole, and absolute data is calculated. Then, the initial pole of the second multipolar resolver is determined from the corrected initial position data obtained by correcting the absolute data with the first multipolar correction data. Next, the initial position data of the second multi-polar resolver is made absolute based on the initial pole, and absolute data is calculated. Then, the corrected initial position data obtained by correcting the absolute data with the second multipolar correction data is output as the rotation initial position data. As a result, the initial position data of the one-rotation detection resolver is corrected by the one-rotation correction data, so that accurate initial position data with respect to the initial position is calculated. Then, even if the initial position data has an error with respect to the output data corresponding to the initial position, the initial pole of the first multipolar resolver is accurately determined. Therefore, since the initial pole of the second multipolar resolver is accurately determined, accurate rotation initial position data with respect to the initial position is calculated. Further, the data is compared with the multi-pole measurement data sequentially obtained from the second multi-pole resolver, and from the result, the pole of the multi-pole measurement data is specified. And
The multipole measurement data is converted into absolute data based on the poles, and corrected output data obtained by correcting the calculated absolute data with the second multipole correction data is output as rotational position data. As a result, the pole for each multi-pole measurement data is accurately specified, and the corrected output data as accurate rotational position data is obtained by the multi-pole measurement data corrected by the second multi-pole correction data.

[0017]

【Example】

[First Embodiment] A first embodiment of the present invention will now be described with reference to FIGS.

As shown in FIGS. 1 and 2, a stator 3 is provided on a fixed side of a direct drive motor for detecting a rotation angle of an output shaft 1 as a detected shaft. In this stator 3, four exciting salient poles 3A are equiangular (90 °).
Are provided in the radial direction at intervals of. A bobbin 4 is mounted on each exciting salient pole 3A, and a coil 5 is wound around the bobbin 4. Each bobbin 4 is fixed to an annular substrate 6 provided on the stator 3 side, and each coil 5 is led out of the motor 21 via the substrate 6. As shown in FIG. 2, at the position of the output shaft 1 opposite to the exciting salient pole 3A,
A disk-shaped eccentric rotor 7 is provided eccentric to the output shaft 1. The eccentric amount of the axis P of the eccentric rotor 7 with respect to the axis O of the output shaft 1 is formed to be approximately 0.6 mm. In this embodiment, the exciting salient pole 3A, the coil 5
And one revolution detection resolver 8 (hereinafter referred to as 1
(Referred to as a rotary resolver).

A stator 9 is provided below the stator 3 (as shown in FIG. 1). Four exciting salient poles 9A are provided on the stator 9 at positions corresponding to the exciting salient poles 3A. Each excitation salient pole 9A has a bobbin 10
And a coil 11 is wound around the bobbin 10. Each bobbin 10 is fixed to an annular substrate 12 provided on the stator 9 side, and each coil 11 is led out of the motor via the substrate 12. As shown in FIG. 2, a gear-shaped multi-pole rotor 13 in which 18 poles 13A are formed at equal angular (20 °) intervals is provided at a position facing the exciting salient pole 9A of the output shaft 1. ing. In the present embodiment, the exciting salient pole 9A, the coil 11, and the multi-pole rotor 13 constitute an 18-pole resolver 14 as a first multi-pole resolver.

A stator 15 is provided below the stator 9 (as shown in FIG. 1). Four exciting salient poles 15 are provided on the stator 15 at positions corresponding to the exciting salient poles 9A.
A is provided. A bobbin 16 is mounted on each of the exciting salient poles 15A, and a coil 17 is wound around the bobbin 16. Each bobbin 16 is fixed to an annular substrate 18 provided on the stator side, and each coil 11 is
Through the motor. A gear-shaped multi-pole rotor 19 in which 132 poles (not shown) are formed at equal angular intervals ((360/132) °) is provided at a position facing the exciting salient poles 15A of the output shaft 1. . In the present embodiment, a 132-pole resolver 20 as a second resolver is constituted by the exciting salient pole 15A, the coil 17 and the multipole rotor 19.

As shown in FIG. 3, one-turn resolvers 8, 1
The 8-pole resolver 14 and the 132-pole resolver 20 are provided in a direct drive motor 21. The reference oscillator 22 is connected to the input side of each of the coils 5, 11, 17 provided in the excitation salient poles 2A, 9A, 15A of the one-rotation resolver 8, the 18-pole resolver 14 and the 132-pole resolver 20, respectively. A reference signal is output to the coils 5, 11, and 17. The output side of each of the coils 5, 11, and 17 is connected to a resolver-to-digital converter (hereinafter referred to as an RD converter) 24 via a changeover switch 23, and signals output from each of the resolvers 8, 14, and 20 are output. It is to be converted to digital data. The RD converter 24 is connected to the control computer 25.

The control computer 25 includes a central processing unit (CPU, the same) 26, a temporary storage memory (RAM, the same) 2
7 and a writable read-only memory (PROM) 28 as a storage means. RPOM2
8 includes a rotational position calculation program and resolvers 8, 1;
Correction data ΔAma, ΔBma, and ΔCma for 4 and 20 are set in advance. Specifically, the RD converter 24
The correction data ΔAma (hereinafter referred to as one-rotation correction data) for each output data Ama from the one-rotation resolver 8 output via the PROM 28 is stored in the PROM 28. Also, RD
18 pole resolver 14 output via converter 24
The correction data ΔBma (hereinafter referred to as 18 pole correction data) for each output data Bma from the PROM 28 is stored in the PROM 28. Further, correction data ΔCma for each output data Cma from the 132-pole resolver 20 output via the RD converter 24 (hereinafter referred to as 132-pole correction data)
Are stored in the PROM 28.

When the CPU 26 fetches the initial position data AK, BK, CK from each of the resolvers 8, 14, 20 by the rotational position calculation program, the CPU 26 first reads the correction data ΔAma for the initial position data AK and reads the initial position data AK Is corrected to calculate the corrected initial position data AKS. Next, the CPU 26 calculates the initial pole TBK of the 18-pole resolver 14 from the corrected initial position data AKS and the initial position data BK.
Ask for. Then, the initial pole TBK and the initial position data B
Absolute data BaK is calculated from K. Next, C
The PU 26 reads the correction data ΔBma for the absolute data BaK, and performs correction with the correction data ΔBma to calculate the correction initial position data BKS. And CP
U26 obtains the initial pole TCK of the 132 pole resolver 20 from the corrected initial position data BKS and the initial position data CK.
Next, the CPU 26 determines the initial pole TCK and the initial position data C
Absolute data CaK is calculated from K. And
Correction data ΔC for this absolute data CaK
ma is read out, the absolute data CaK is corrected with the correction data ΔCma, the corrected initial position data CKS is calculated, and the corrected initial position data CKS is output as the rotation initial position data.

Further, the CPU 26 compares the output data Cma (t) sequentially captured with the output data CK previously captured, and compares the output data Cma (t) with the pole TCK where the output data Cma (t) exists.
(T) is specified. Then, absolute data CaK (t) is obtained from the pole TCK (t) and the output data Cma (t), corrected by the corresponding correction data ΔCma to calculate corrected position data CKS (t), and output as rotation position data. It is supposed to.

The RAM 27 temporarily stores each data calculated by the CPU 26. Next, the PR
A correction data creation device for creating the correction data ΔAma, ΔBma, ΔCma for each of the resolvers 8, 14, 20 stored in the OM 28 will be described.

As shown in FIG. 4, the correction data ΔAma, Δ
Direct drive motor 2 in which Bma and ΔCma are created
The output shaft 1 has a measuring motor 31 and a reference encoder 3
2 are coaxially connected and the reference encoder 32 is connected to a control computer 33. The reference encoder 32 outputs output data corresponding to the rotation angle of the motor 21 to the control computer 33. A reference oscillator 34 is connected to each of the resolvers 8, 14, and 20, and each of the resolvers 8, 14, and 20 is connected to a resolver-to-digital converter (hereinafter referred to as an RD converter) 36 via a changeover switch 35, and an RD converter. Reference numeral 36 is connected to the control computer 33. Then, when the measurement signal is output from the reference transmitter 34, output data Ama, Bma, Cma corresponding to the rotation angle are output from the resolvers 8, 14, 20 via the RD converter 36 to the control computer 33. It has become. The measuring motor 31 is controlled by a control computer 33.

The control computer 33 has a CPU 37 and the same PRO as those used for the control computer 25.
M28 and RAM38. PROM2
8 has a built-in correction data creation program. C
The PU 37 uses the correction data creation program to execute each of the resolvers 8, 14, and
The output data EA, EB, and EC of the reference encoder 32 corresponding to the output data Ama, Bma, and Cma from the processor 20 are taken in, and correction data ΔAma, ΔBma, and ΔCma for each of the output data Ama, Bma, and Cma are calculated. I have.
The CPU 37 controls the rotation of the measuring motor 31 and switches the changeover switch 35. PROM2
Reference numeral 8 stores the calculated correction data ΔAma, ΔBma, and ΔCma.

From the one-rotation resolver 8 to the RD converter 36
As shown in FIG. 5, the output data Ama output through the maximum data value R with a rotation angle of 360 ° as one cycle
(In the present embodiment, it is 2 ¹² , R = 4096) and is roughly displayed as a linear graph. Also, 18 pole resolver 1
The output data Bma output from No. 4 via the RD converter 36 is schematically displayed as a graph composed of a plurality of straight lines of the maximum data value R (2 ¹² = 4096) with one cycle of (360/18) °. The output data Cma output from the 132-pole resolver 20 via the RD converter 36
Is roughly displayed as a graph composed of a plurality of straight lines of the maximum data value R (2 ¹² = 4096) with one cycle of (360/132) °.

Next, a method of creating correction data by the above-described correction data creating apparatus will be described. As the creation of the correction data, first, the CPU 37 executes a reference data creation process. First, the reference data creation processing is performed by the changeover switch 3
5 is switched to a one-turn resolver 8 and its output data Ama
Enters the standby state for taking in
1 to rotate the motor 21 from an initial position, which is its initial rotational position. The CPU 37 turns RD
The output data Ama from the converter 36 is equal to the set number r (= 2
² = 4) Every time it changes, the output data Ama [i] value as one rotation setting data 0, r, 2r,..., (X−2) r, (x−1) r, where x = 2 ¹⁰ = 1024, which is the number of data per rotation. The output data EA [i] as reference data from the reference encoder 32 corresponding to
i ≦ x−1∴0 ≦ i ≦ 1023; i is an integer) EA

[0], EA [1], ..., EA [x-2], EA
[X-1] is obtained. Then, the value of the output data EA [i] of the reference encoder 32 with respect to the output data Ama [i] at that time, that is, (0, EA)

[0]), (r, EA [1]),... (I · r, EA [i]),... ((X−2) r, EA [X-2]), ((x-1) r, EA [(x-1)]) are stored in the RAM 38. Here, x (= 2 ¹⁰ = 10
24) is a value obtained by dividing the maximum data value R (= 2 ¹² = 4096) by the set number r (= 2 ² = 4).
This is the number of data that the CPU 37 takes in from the one-rotation resolver 8 while rotating by 0 °.

Next, the CPU 37 sets the changeover switch 35 to 1
It switches to the 8-pole resolver 14 and enters a standby state for taking in the output data Bma, while driving the measuring motor 31 to rotate the motor 21 from the initial position. CPU
Reference numeral 37 denotes the output data Bma [as the first multi-pole setting data from the 18-pole resolver 14 each time the output data Bma from the RD converter 36 changes by a set number s (= 2 ⁵ = 32) with rotation. v] Value (0, s, 2s, ..., (m-1) s) ₁ , (0, s, 2s, ..., (m-1) s) ₂ , ... .. (0, s, 2s,..., (M-1) s) ₁₈ where m = 2 ⁷ = 128, which is the number of data per pole. The output data EB [v] (where 0 ≦ v ≦
y-1∴0 ≦ v ≦ 2303; v is an integer; y = m × 18 = 2304) EB

[0], EB [1], ..., EB [y-2], EB
[Y-1] is obtained. Then, the value of the output data EB [v] of the reference encoder 32 with respect to the output data Bma [v] at that time, that is, (0, EB

[0]), (s, EB [1]), ... ((m-1) s, EB [m-1]), (0, EB [m]), (s, EB (M + 1)),... ((M-2) s, EB [y-2]) ((m-1) s, EB [y-1]) are stored in the RAM 38. Here, m (= 2 ⁷ = 12)
8) sets the maximum data value R (= 2 ¹² = 4096) to the set number s
(= 2 ⁵ = 32), and the value of the motor 21 is (3
60/18) °, the CPU 37
Is the number of data taken from the 18-pole resolver 14. Therefore, when the 18-pole resolver 14 rotates 360 °, the total number of data becomes y (= m × 18 = 2304).

Next, the CPU 37 sets the changeover switch 35 to 1
It switches to the 32-pole resolver 20, enters a standby state for capturing the output data Cma, drives the measuring motor 31, and rotates the motor 21 from the initial position. The CPU 37 outputs the output data Cma from the RD converter 36 with the rotation.
Every time the set number t (= 2 ⁷ = 128) changes, that is, 1
Output data Cma [p] as the second multi-pole setting data from the 32-pole resolver 20 (0, t, 2t, ..., (n-1) t) ₁ , (0, t, 2t, ..., ( n−1) t) ₂ , (0, t, 2t,..., (n−1) t) ₁₃₂ where n = 2 ⁵ = 32 and 1 The number of data per pole. Is output data EC [p] as reference data from the reference encoder 32 corresponding to the following equation (where 0 ≦ p ≦
z-1∴0 ≦ p ≦ 4223; p is an integer; z = n × 132 = 4224) EC

[0], EC [1], ..., EC [z-2], EC
[Z-1] is obtained. Then, the value of the output data EC [p] of the reference encoder 32 with respect to the output data Cma [p] at that time, that is, (0, EC

[0]), (s, EC [1]), ... ((n-1) s, EC [n-1]), (0, EC [n]), (s, EC (n + 1)),... ((N-2) s, EC [z-2]) ((n-1) s, EC [z-1]) are stored in the RAM 38. Here, n (= 2^Five= 32)
Is the maximum data value R (= 2 ¹²= 4096) to the set number t (=
2⁷= 128), and the value of the motor 21 is (36)
0/132) °, that is, every pole
Is the number of data taken in from the 132 pole resolver 20.
Therefore, when the 132 pole resolver 20 rotates 360 °,
The total number of data becomes z (= n × 132 = 4224).
You.

Next, the CPU 37 executes a correction data calculation process. The correction data calculation processing is performed by measuring each output data Ama [i], Bma of each of the resolvers 8, 14, and 20.
Reference encoder 32 for each value of [v] and Cma [p]
Output data EA [i], EB [v], EC [p]
, The correction data ΔAma [i], ΔBma [v], ΔCma [p] for the output data Ama [i], Bma [v], Cma [p] of each resolver 8, 14, 20 are calculated. create.

First, the CPU 37 calculates | EA [i] −EB [j] | (0 ≦ j ≦ y−1∴0 ≦ j ≦ 2303; j is an integer) for the output data EA [i] of the reference encoder 32. ) Is minimized, and the output data EB [j] corresponding to the number i of the output data EA [i] is obtained.
Is determined. Then, the i-th one-rotation correction data ΔAma [i] of the one-rotation resolver 8 is calculated by the following equation, and P
It is stored in the ROM 28.

ΔAma [i] = j · s−i · r × 18 = 32j−4i × 18 where j · s is the output data Bma of the 18-pole resolver 14.
This is a value obtained by converting [j] into an absolute value. I · r represents output data Ama [i] of the one-rotation resolver 8, and i · r
r × 18 is a value obtained by converting the output data Ama [i] into the output data Ama of the 18-pole resolver 14. Therefore, s
Is 32 and r is 4, ΔAma = 32j−4 · i × 18
Becomes

Similarly, the CPU 37 controls the reference encoder 32
EB [v] −EC [w] | (0 ≦ w ≦ z−1∴0 ≦ w ≦ 4223; w is an integer) with respect to the output data EB [v]. [W] is obtained, and the number w of the output data EC [w] corresponding to the number of the output data EB [v] is obtained. Then, the v-th 18-pole correction data ΔB as the first multi-pole correction data of the 18-pole resolver 14
ma [v] is calculated by the following equation and stored in the PROM 28.

ΔBma [v] = w · t−v · s · (132/18) where w · t is the output data Z of the 132 pole resolver 20
This is the absolute value of ma [p]. Also, vs
Represents output data Bma [v] of the 18-pole resolver 14,
vs. (132/18) is the output data Bma [v]
Is converted to output data Cma of the 132-pole resolver 20.

Next, the CPU 37 operates the reference encoder 32 corresponding to each output data Cma [p] of the 132-pole resolver 20.
Output data EC [p] to its output data Cma [p]
Is obtained by the following equation.

Ig [p] = EC [p] · z · t / Emax (where Emax is the maximum data value of the reference encoder 32) Here, the right side of the above equation is the output data EC [p] of the reference encoder 32. This is a value converted into output data Cma of the 132-pole resolver 20.

Next, the CPU 37 calculates 132-pole correction data ΔCma [p] as second multi-pole correction data from each output data Cma and the corresponding reference data Ig [p] according to the following formula, and stores it in the PROM 28. Remember.

ΔCma [p] = Ig [p] -pt Here, the second term pt on the right side of the above equation is the output data Cma
[P] is an absolute value.

As described above, one rotation correction data ΔAma [i], 1 rotation correction data ΔAma [i] for each output data Ama [i] of one rotation resolver 8
1 for each output data Bma [v] of the 8-pole resolver 14
8-pole correction data ΔBma [v] and 132-pole resolver 20
The 132 pole correction data ΔCma [p] for each of the output data Cma [p] is generated. Each correction data ΔAma
[I], ΔBma [v], ΔCma [p] are stored in the PROM 28. Each correction data ΔAma [i], ΔBma
The PROM 28 in which [v] and ΔCma [p] are stored is built in the control computer 25 of the rotation angle detecting device.

Next, a rotation angle for measuring the rotation angle of the output shaft 1 of the direct drive motor 21 in which the correction data ΔAma [i], ΔBma [v], and ΔCma [p] of each of the resolvers 8, 14, 20 has been created. A method of detecting the rotation angle by the detection device will be described.

The control computer 25 of the rotation angle detecting device stores the correction data ΔA of each of the resolvers 8, 14, and 20.
P in which ma [i], ΔBma [v], ΔCma [p] are stored
ROM 28 is incorporated.

First, at the position immediately before the start of the motor 21, that is, at the initial position, the CPU 26 performs a first corrected initial position data calculating process as first corrected initial position data calculating means. In the first correction initial position data calculation process, first,
Output data (hereinafter referred to as initial position data) AK corresponding to the initial position θK of the one-rotation resolver 8 and an 18-pole resolver 1
The output data (hereinafter referred to as initial position data) BK corresponding to the initial position of No. 4 and the output data (hereinafter referred to as initial position data) CK corresponding to the initial position of the 132-pole resolver 20 are taken in.

Then, the CPU 26 divides the acquired initial position data AK of the one-rotation resolver 8 by the set number r, and rounds up or down the decimal point to obtain a value rounded down. The correction output data ΔAma [i] corresponding to the obtained value is read. That is, ΔAma [i] = ΔAma [[AK / r + 0.5]] where [] is a Gaussian symbol, and the above equation is a value obtained by dividing the initial position data AK by the set number r (= 2 ² ). Means the value rounded off. That is, ΔAma [[AK / r +
0.5]] means one-turn correction data ΔAma corresponding to output data Ama closest to initial position data AK. Then, this correction data ΔAma [[ΔAma _k / r + 0.
5]], the corrected initial position data AKS of the single-rotation resolver 8
Is calculated by the following equation.

AKS = AK × 18 + ΔAma [[AK / r + 0.5]] Next, the CPU 26 performs a first initial pole finding process as first initial pole finding means of the 18-pole resolver 14. In the first initial pole indexing process, first, the corrected initial position data AKS of the one-rotation resolver 8 is divided by m · s (= R) which is the maximum data value of the RD converter 24, and its quotient A
KS (H) and AKS (L) are found. This quotient AKS
The value obtained by adding 1 to (H) becomes the temporary initial pole TBK of the 18-pole resolver determined from the corrected initial position data AKS.

AKS / (ms) = AKS (H)... AKS (L) Next, the CPU 26 sets the initial position data BK and the remaining AKS
(L) is calculated, and a value B obtained by dividing the difference by the data value m · s is calculated by the following equation.

B = (BK-AKS (L)) / (ms) This value B is the ratio of the difference between the initial position data BK and the remainder AKA (L) to the number of data per pole of the 18-pole resolver 14. Represents With the value of this value B, the corrected initial position data A
Temporary initial pole TBK of 18 pole resolver 14 determined by KS
(= AKS (H) +1) is corrected to the true initial pole which actually outputs the initial position data BK. That is, 18
True initial pole TBK of pole resolver 14 (= RM / (ms)
+1). RM is determined as follows.

When -3 / 8≤B≤3 / 8, RM = A
KS (H) × (ms) (In this case, the initial pole is TBK = AKS (H) +1) When 5/8 ≦ B <1, RM = (AKS (H) −
1) × (ms) (In this case, the initial pole is TBK = AKS (H)) When −1 <B ≦ −5 / 8, RM = (AKS (H) +1)
× (m · s) (at this time, the initial pole is TBK = AKS (H) +2) Here, when −3 / 8 ≦ B ≦ 3/8, the pole TBK that outputs the initial position data Bk (ie, The initial pole of the 18-pole resolver 14) is the corrected initial position data AKS of the one-turn resolver 8.
The temporary initial pole TBK (= AKS (H) +1)
And the initial pole TBK is AKS (H) +
It becomes 1. If 5/8 ≦ B <1, the pole TBK that outputs the initial position data Bk is the pole (AKS
(H)), and the initial pole TBK is AKS (H)
Becomes If −1 <B ≦ −5 / 8, the pole TBK that outputs the initial position data BK is the pole (AKS
(H) +2), and the initial pole TBK is AKS
(H) +2.

Here, the initial position data Bk and the remainder AKS
It is assumed that the difference from (L) is at most smaller than R / 2. If the difference is greater than R / 2, if the difference between the initial position data Bk and the remainder AKS (L) is assumed, there will be two or more combinations in the positional relationship between the two, and the pole is specified. Because they can no longer do it. That is, the value of B is in the range of -1 <B <1, and -1 /
In the range of 2 <B <1/2, it can be seen that the pole TBK from which the initial position data BK was output and the temporary pole corresponding to the remainder AKS are the same pole. In the range of -1 <B <-1/2,
It can be seen that the pole TBK that has output the initial position data BK is the pole after the pole corresponding to the remainder AKS. Conversely, 1/2 <
In the range of B <1, the pole T that outputs the initial position data BK
It can be seen that BK is the pole before the pole corresponding to AKS.

Therefore, in the present embodiment, the range of the value B is set to the above three ranges, ie, -3 / 8≤B≤3 / 8, 5 / 8≤B
<1 and −1 <B ≦ −5 / 8, −5/8 <B <−3
Excluding the range of / 8 and 3/8 <B <5/8,
This is to prevent the detection error of the initial position data AK and BK from erroneously determining the relationship between the pole where the initial position data BK exists and the pole obtained from the corrected initial position data AKS. That is, when the value B in this range is obtained, the CPU 26 determines that the data is abnormal, does not determine the initial pole TBK, and outputs the next output data Ama, Bma obtained by the rotation of the motor 21 to the initial position. As data AK and BK, an initial pole TBK is determined.

Next, the CPU 26 executes a first absolute data calculation process as a first absolute data calculation means. In the first absolute data calculation process, the absolute data BaK of the 18 pole resolver 14 is calculated from the value RM calculated in the first initial pole indexing process and the initial position data BK of the 18 pole resolver 14 by the following equation.

BaK = RM + BK Next, the CPU 26 executes a second correction initial position data calculation process as a second correction initial position data calculation means. In the second correction initial position data calculation processing, the correction initial position data BKS of the 18-pole resolver 14 is calculated by the following equation.

BKS = BaK × 132/18 + ΔBma [[B
aK / s + 0.5]] That is, the calculated absolute data BaK is divided by the set number s, and the fractional part thereof is rounded off to obtain a truncated value. 18 pole correction data ΔBma corresponding to the obtained value
Absolute data BaK at 132 pole resolver 20
The corrected initial position data BKS is calculated by correcting the value converted to the output data Cma.

Next, the CPU 26 executes a second initial pole finding process as second initial pole finding means. The second initial pole indexing process is based on the calculated 18 pole resolver 1
4 is divided by n · t (= R), which is the maximum number of data of the RD converter 24, and the quotient BKS is obtained.
(H) and the remainder BKS (L) are obtained. This quotient BKS (H)
Is the temporary initial pole T of the 132-pole resolver 20.
CK.

BKS / (nt) = BKS (H)... BKS (L) Next, the CPU 26 sets the initial position data CK and the remainder BKS.
(L) is calculated, and a value C obtained by dividing the difference by the data value n · t is calculated by the following equation.

C = (CK−BKS (L)) / (nt) This value C is the ratio of the difference between the initial position data CK and the remainder BKS (L) to the number of data per pole of the 132 pole resolver 20. Represents With this value C, the corrected initial position data BKS
Tentative initial pole TCK of 132 pole resolver 20 determined in
(= BKSH + 1) is corrected to the true initial pole which actually outputs the initial position data CK. That is, the initial pole TCK of the 132 pole resolver 20 (= RN / (nt) +1) as follows.
To identify. RN is determined as follows.

When -3 / 8≤C≤3 / 8, RN = B
KS (H) × (n · t) (In this case, the initial pole is TCK = BKS (H) +1) When 5/8 ≦ C <1, RN = (BKS (H) −
1) × (n · t) (at this time, the initial pole is TCK = BKSH) When −1 <C ≦ −5 / 8, RN = (BKS (H) +1)
× (n · t) (at this time, the initial pole is TCK = BKS (H) +2) Here, when −3 / 8 ≦ C ≦ 3/8, the pole TCK that outputs the initial position data CK (ie, 132 pole resolver 20
Is the same pole as the temporary initial pole (BKSH + 1) determined by the corrected initial position data BKS.
The initial pole TCK becomes BKSH + 1. In the case of 5/8 ≦ C <1, the pole TCK that has output the initial position data CKa is the pole (BKSH) before the provisional initial pole TBK, and the initial pole TCK is BKSH. When -1 <C≤-5 / 8, the pole TCK that outputs the initial position data CK is the pole (BKSH + 2) after the tentative initial pole TBK, and the initial pole TCK is BKSH + 2. Become.

Here, the initial position data Ck and the remainder BKS
It is assumed that the difference from (L) is at most smaller than R / 2. If the difference is greater than R / 2, two or more combinations occur in the positional relationship assumed from the difference between the initial position data Ck and the remainder BKS (L). Because they can no longer do it. That is, the value of C is in the range of -1 <C <1, and -1 /
In the range of 2 <C <1/2, it can be seen that the pole TCK from which the initial position data CK was output and the temporary pole corresponding to the remainder BKS are the same pole. In the range of -1 <C <-1/2,
It can be seen that the pole TCK that output the initial position data CK is the pole after the pole corresponding to the remainder BKS. Conversely, 1/2 <
In the range of C <1, the pole T that outputs the initial position data CK
It can be seen that CK is the pole before the pole corresponding to BKS.

Therefore, in the present embodiment, the range of the value C is set to the above three ranges, ie, -3 / 8≤C≤3 / 8, 5 / 8≤C
<1 and −1 <C ≦ −5 / 8, −5/8 <C <−3
Excluding the range of / 8 and 3/8 <C <5/8,
Due to the detection error of the initial position data AK, BK, CK, the pole where the initial position data CK exists and the corrected initial position data B
This is to prevent the relationship with the pole determined by the KS from being erroneously determined. That is, when the value C in this range is obtained, the CPU 26 determines that the data is abnormal and sets the initial pole TCK
, And the output data Ama, Bma, Cma obtained next by the rotation of the motor 21 are initialized to the initial position data AK.
, BK, and CK to determine the initial pole TCK.

Next, the CPU 26 executes a second absolute data calculation process as a second absolute data calculation means. The second absolute data calculation process includes the value RN calculated in the second initial pole determination process and the initial position data CK of the 132 pole resolver 20.
Data from the 132-pole resolver 20 to CaK
Is calculated by the following equation.

CaK = RN + CK Next, the CPU 26 executes third correction initial position data calculation processing as third correction initial position data calculation means. In the third correction initial position data calculation processing, the correction initial position data CKS of the 132 pole resolver 20 is calculated by the following equation.

CKS = CaK + ΔCma [[CaK / t + 0.5]] That is, the calculated absolute data CaK is divided by the set number t, and the value obtained by rounding off the decimal point and rounding down is obtained. 132 pole correction data ΔC corresponding to the obtained value
The absolute data Cak is corrected by ma and corrected initial position data CKS is calculated.

Then, the CPU 26 outputs the calculated corrected initial position data CKS as rotation initial position data at the initial position θK. Next, the CPU 26 fetches the initial position data AK, BK and CK, and every time a predetermined time t elapses after the fetching of the initial position data AK, BK and CK, the pole allocation processing as the pole allocation means and the third absolute data calculation means The absolute data calculation processing and the correction position data processing as correction position data calculation means are repeatedly executed. This time t is set to a value such that the maximum rotation speed of the motor 21 does not jump over the rotation angle of the 132 pole resolver 20 with respect to one pole.

In the pole assignment processing, first, it is determined whether or not the following inequality holds for output data Cma (t) of the 132 pole resolver 20 obtained after time t. | CK−Cma (t) | ≧ R / 2 | CK−Cma (t) | represents the absolute value of (CK−Cma (t)). The above inequality is used to determine whether the pole TCK (t) where the output data Cma (t) of the 132 pole resolver 20 exists is the same as the initial pole TCK where the initial position data CK exists, or has shifted to the next pole. Things. That is, by comparing the difference between the initial position data CK and the output data Cma (t) with half the number R of data per pole of the 132-pole resolver 20, the data CK and the output data Cma (t) have the same pole. , Or data obtained from adjacent poles.

If the inequality expression does not hold, that is, if the pole where the output data Cma (t) of the 132-pole resolver is the same as the initial pole TCK, the CPU 26 performs a third absolute data calculation process. The third absolute data calculation process is performed on the 13th data corresponding to the output data Cma (t).
Absolute data CaK (t), which is absolute data in the bipolar resolver 20, is calculated by the following equation.

CaK (t) = RN + Cma (t) where RN = (TCK-1) .times. (Nt) Then, the CPU 26 calculates the corrected output data CKS (t) as a corrected position data calculation process by the following equation. Calculate and output as rotational position data.

CKS (t) = CaK (t) + ΔCma [[CaK
(T) /t+0.5]] On the other hand, if the inequality expression holds, that is, 132
When the pole having the output data of the pole resolver moves to the pole next to the initial pole TCK, the following calculation is performed as pole assignment processing.

RN = RN ± (nt) This equation indicates that the pole in which the output data Cma (t) of the 132 pole resolver has moved to the pole next to the initial pole TCK.
Then, the CPU 26 calculates the absolute data CaK (t) by the following equation as a third absolute data calculation process.

CaK (t) = RN + Cma (t) where RN = RN ± (nt) = (Tc _k− 1) × (n
T) ± (nt) The CPU 26 calculates the corrected position data CKS (t) by the following equation as a corrected position data calculation process, and outputs it as rotational position data.

CKS (t) = CaK (t) + ΔCma [[CaK
(T) /t+0.5]] Thereafter, every time the time t elapses, the CPU 26
The output data Cma (2t) and Cma (3
t),. Then, each output data Cma (2
t), Cma (3t),... are sequentially compared with previously obtained output data Cma (t), Cma (2t),..., and based on the comparison result, poles TCK (t), TCK (2t),. Judge the change. From the comparison result, a new corresponding pole is specified, and this pole and the output data Cma (2t), Cma (3t),
.. Are used to calculate the absolute data CaK. further,
This absolute data CaK is converted to 132 pole correction data Δ
Cma to calculate the corrected position data CKS (t),
It is output as rotation position data at that rotation position.

As described above, the direct drive motor 2
Reference numeral 1 denotes output data Ama [i], Bma of each of the resolvers 8, 14, and 20 in the correction data creating device before use.
[V], correction data ΔAma [i] for Cma [p],
ΔBma [v] and ΔCma [p] are created. The created correction data ΔAma [i], ΔBma [v], ΔCma [p]
Is stored in the PROM 28 in the CPU 37. The PROM 28 storing the correction data ΔAma [i], ΔBma [v], ΔCma [p] is built in the control computer 25 of the rotation angle detecting device.

As shown in FIG. 5, when no external force is applied to the output shaft 1 of the motor 21, the CPU 26 determines that the output shaft 1 of the motor 21 is at the initial position θK and the initial position of the one-turn resolver 8. Import data AK. CPU2
6 uses this initial position data AK as one rotation correction data ΔAma
(= ΔAK = ΔAma [AK / r + 0.5]
The correction initial position data AKS is calculated. Then, based on the corrected initial position data AKS, the initial pole TBK (= RM / (ms)) of the 18-pole resolver 14 corresponding to the initial position θK.
+1).

Next, the CPU 26 determines the specified initial pole T
Absolute data BaK is calculated from BK and the initial position data BK of the 18-pole resolver 14, and corrected using the corresponding 18-pole correction data ΔBma to calculate corrected initial position data BKS. Then, based on the corrected initial position data BKS, the initial pole TCK (= RN / (nt) +1) of the 132 pole resolver 20 corresponding to the initial position θK is specified. Here, the initial pole TCK of the 132 pole resolver 20 calculated from the initial position data AK is represented by TCK [K]. Next, CPU
26 is the initial pole TCK [K of the identified 132 pole resolver 20;
], And the absolute data CaK is calculated from the initial position data CK, and corrected using the corresponding 132 pole correction data ΔCma to calculate corrected initial position data CKS. And
The corrected initial position data CKS is output as rotation initial position data corresponding to the initial position θK.

On the other hand, when an external force in the radial direction is applied to the output shaft 1 of the motor 21 at the initial position, the center of the eccentric rotor 7 of the one-rotation resolver 8 shifts with respect to the center of each exciting salient pole 9. In this state, the rotation angle θ-the output data Ama changes with respect to the characteristics at the time of creating the correction data.
As shown by a two-dot chain line, the output data A originally corresponding to the rotation angle θW as the initial position data at the initial position θK.
W is captured. 13 corresponding to the output data AW
The pole of the two-pole resolver 20 is TCK [W].

In this state, without using the 18-pole resolver 14,
132 from the initial position data AK of the single-rotation resolver 8
When calculating the initial pole TCK of the pole resolver 20, first,
The initial position data AW is corrected by the one-rotation correction data ΔAma to calculate corrected initial position data BKS. And
From the corrected initial position data BKS, the 132 pole resolver 20
Are identified. In this case, since the number of poles of the 132 pole resolver 20 is large, even if the corrected initial position data BKS slightly deviates from the corrected initial position data calculated from the initial position data AK, the pole T with respect to the actual initial position θK is obtained.
The pole TCK [w] deviated from CK [K] is specified. Then
Rotation initial position data for the initial position is calculated from the pole TCK [w] and the initial position data CK. As a result, the rotation initial position data for the rotation angle θW is output even though the actual initial position is the rotation angle θK.

In the above case, as in this embodiment, 1
When using the 8-pole resolver 14, the initial position data AK
From the corrected initial position data AKS, the initial pole TBK of the 18-pole resolver 14 is specified from the corrected initial position data AKS. In this case, since the number of poles of the 18-pole resolver 14 is small, the output data A obtained as the initial position data is used.
Even if the corrected initial position data AKS obtained from W is slightly deviated from the corrected initial position data calculated from the initial position data AK, the pole TBK [K] with respect to the actual initial position θK is specified. Next, the corrected initial position data BKS of the 18-pole resolver 14 is calculated from the pole TBK [K] and the initial position data BK of the 18-pole resolver 14. The initial pole TCK of the 132 pole resolver 20 is specified from the corrected initial position data BKS. Therefore, the initial pole T of the 132 pole resolver 20
The pole TBK of the 18-pole resolver 14 whose CK is accurately specified with respect to the initial position, and the output data AK of the one-rotation resolver 8
Since it is specified based on the initial position data BK of the 18-pole resolver 14 which is less affected by the eccentricity of the output shaft 1, the pole TCK with respect to the actual initial position θK is specified with high accuracy. Then, the specified pole TCK and the output shaft 1
Since the rotation initial position data is obtained from the initial position data CK of the 132 pole resolver 20 which is hardly affected by the eccentricity, the angle detection with high accuracy is performed.

Also, the CPU 26 takes one again each time the time t, 2t,...
The output data Cma (t), Cma (2) of the 32-pole resolver 20
t),. Then, the successive output data CK, C
output data Cma (t), Cma
(2t),... Correspond to the poles TCK (t), TCK (2t),
Judge the change of ... and specify a new pole. And
From the newly specified poles TCK (t), TCK (2t),... And the output data Cma (t), Cma (2t),. CKS
(2t),... Are calculated and output as rotational position data. That is, since the change of the pole TCK is determined by comparing the output data Cma of the 132 pole resolver 20 with high accuracy, the pole TCK corresponding to the output data Cma is specified with high accuracy. Then, the specified pole TCK and the output data Cma
Since the rotational position data is calculated from, the angle detection with high accuracy is performed.

As described above, according to the rotation angle detecting device of this embodiment, the output shaft 1 of the motor 21 receives an external force in the radial direction, and the center of the eccentric rotor 7 of the one-rotation resolver 8 is located at the center of the stator 2. As a result, even if the output data AW that is shifted from the output data AK corresponding to the initial position θK is output, the initial pole TBK of the 18-pole resolver 14 for the output data AK can be specified accurately. Then, the absolute data BaK is calculated from the initial pole TBK and the initial position data BK of the 18-pole resolver 14, the initial pole TCK of the 132-pole resolver 20 is specified, the absolute data CaK of the initial position data CK is calculated, and the initial rotation is calculated. Position data can be determined.

Further, the change of poles is obtained from a comparison result between the output data Cma (t), Cma (2t),... Of the 132-pole resolver 20 which is sequentially taken in and the output data CK, Cma (t),. Is determined from the newly specified poles and the output data Cma (t), ΔCma (2t),...
t), CKS (3t),... are calculated. Therefore, accurate rotational position data for the rotational position θ can be sequentially obtained. (Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS. It should be noted that the rotation angle detecting device of the present embodiment is different only in the one-rotation resolver and the 18-pole resolver, and the other parts are the same.

As shown in FIGS. 6 to 8, the stator 40 has four exciting salient poles 41 provided on the same inner peripheral surface at equal angular (90 °) intervals in the radial direction. The upper half (in FIG. 6) of each exciting salient pole 41 in the direction of the output shaft 1 has an output shaft 1
A sub-excitation salient pole 42 projecting to the side is formed. A bobbin 43 is mounted on each of the exciting salient poles 41, and a coil 44 is wound around the bobbin 43. Each bobbin 43 is fixed to an annular substrate 45 arranged on the stator 40 side, and each coil 44 is led out of the motor 21 via the substrate 45.

On the same inner peripheral surface of the stator 40 as the exciting salient poles 41, four exciting salient poles 46 are provided radially between the exciting salient poles 41, respectively. A sub-excitation salient pole 47 projecting toward the output shaft 1 is formed in a lower half (in FIG. 6) of each of the excitation salient poles 46 in the direction of the output shaft 1. A bobbin 48 is mounted on each of the exciting salient poles 46, and a coil 49 is wound around the bobbin 48. Each bobbin 48 is fixed to the board 45, and each coil 49 is led out of the motor 21 via the board 45.

That is, as shown in FIG. 8, the exciting salient poles 41 and 46 are alternately arranged with respect to the stator 40, and the auxiliary exciting salient poles 42 and 47 are alternately shifted in the axial direction of the stator 40. It is located in the position.

As shown in FIG. 7, a disc-shaped eccentric rotor 50 is provided at a position of the output shaft 1 opposite to the auxiliary excitation salient pole 42 eccentrically with respect to the output shaft 1. The amount of eccentricity of the axis P of the eccentric rotor 50 with respect to the axis O of the output shaft 1 is formed to be approximately 0.6 mm. The output shaft 1 has 18 poles 51A at positions facing the sub-excitation salient poles 47.
Is provided. In the present embodiment, a one-turn resolver 52 is configured by the exciting salient pole 41, the coil 44, and the eccentric rotor 50, and the exciting salient pole 4
An 18-pole resolver 53 as a first multi-pole resolver is constituted by the 6, the coil 49 and the multi-pole rotor 51.

The rotation angle detecting device according to the present embodiment has the same operation as the first embodiment. Further, according to the rotation angle detecting device of the present embodiment, the exciting salient pole 41 of the one-turn resolver 52 and the exciting salient pole 46 of the 18-pole resolver 53 are provided on the same stator 40. The eccentric rotor 50 is opposed to a sub-excitation salient pole 42 provided on the excitation salient pole 41 to form a one-turn resolver 52, and the multipole rotor 51 is a sub-excitation salient pole provided on the excitation salient pole 46. The 18-pole resolver 53 is configured with the 47s opposed to each other. As a result, the rotor 50 of the one-rotation resolver 52 and the rotor 51 of the 18-pole resolver 53 can be arranged close to each other, and
The length of the 2- and 18-pole resolver 53 in the direction of the output shaft 1 can be reduced to reduce the size.

Further, since the stator 40 is shared by the one-rotation resolver 52 and the 18-pole resolver 53 and the number of parts is reduced, the cost of parts and the cost of assembly can be reduced. still,
The present invention is not limited to the above embodiments, and may be configured as follows, for example, without departing from the spirit of the invention.

(1) In the above embodiment, the single-rotation resolver 8, the 18-pole resolver 14, and the 132-pole resolver 20 are provided as the resolvers constituting the rotation angle detecting device.
The number of poles of the 8-pole resolver 14 and the 132-pole resolver 20 may be appropriately changed.

(2) In the above embodiment, three resolvers including the one-rotation resolver 8 are used. However, the number of multipolar resolvers may be three or more, and four or more resolvers may be used. .

(3) In the above embodiment, the corrected initial position data CKS of the 132-pole resolver 20 was calculated by the following equation. CKS = CaK + ΔCma [[CaK / t + 0.5]] This may be calculated by the following equation.

CKS = CaK + {(t−CKS (L)) / t}
× ΔCma [CKS (H)] + (CKS (L) / t) × ΔCma
[CKS (H) +1] Here, it is assumed that CaK / t = CKS (H) (quotient)... CKS (L) (remainder). That is, in the above equation, after dividing the absolute data CaK by t, the correction data ΔCma [p] corresponding to the value p obtained by rounding off the absolute data CaK is converted to the absolute data CaK.
Added. Therefore, a correction error has occurred by adding the correction data ΔCma [p]. This is taken as the correction data ΔCma [p] and the integer value CKS on both sides of CaK / t.
The correction data ΔCma [p] of the value p corresponding to (H) and (CKS (H) +1) is averaged by CKS (L), and the correction data {(t−CKS (L)) / t} × ΔCma [CKS
(H)] + (CKS (L) / t) × ΔCma [CKS (H) +
By using [1], errors due to correction can be reduced.

(4) In the above embodiment, the following ranges were used for the correction of the initial pole of the 18-pole resolver 14 and the correction of the initial pole of the 132-pole resolver. -3 / 8≤B (C) ≤3 / 8 5 / 8≤B (C) <1-1 <B (C) ≤-5 / 8 This is because there is a detection error in the initial position data AK, BK, CK. In order to prevent a specific error of the pole near B (C) =-1/2 or 1/2 in the case of
It is not necessary to use 3/8, 3/8 or -5/8, 5/8, for example, instead of -3/8, 3/8, -7/16,
Using 7/16, instead of -5/8, 5/8, -9/1
6, 9/16 may be used.

(5) In the above embodiment, the correction data ΔAma [i] and ΔBma of the resolvers 8, 14, and 20 are previously determined.
[V] and ΔCma [p] are created, and each resolver 8, 14,
The corrected initial position data AKS, BKS, and CKS were calculated by adding the initial position data AK, BK, and CK to the respective 20 initial position data. This is converted to correction data ΔAma [i], ΔBma [v], ΔCma
The initial position data AK is used as the absolute data AKS without performing the correction by [p], and the absolute data BaK
May be used as the corrected initial position data BKS, and the absolute data CaK may be used as the corrected initial position data CKS.

(6) In the above embodiment, each resolver 8,
Although the embodiment has been described in the case where the motors 14 and 20 are provided in the direct drive motor 21, the embodiment may be implemented in a case where the rotation angle of the shaft to be detected is detected by being externally attached to the shaft to be detected.

[0094]

As described above in detail, according to the first aspect of the present invention, the detection error of the rotation angle generated as a result of applying an excessive external force in the radial direction of the output shaft provided with the rotor is suppressed. be able to.

According to the second aspect of the present invention, in addition to the above-described effects, the size of the single-rotation resolver and the multipolar resolver can be reduced as a whole. Also, parts costs and assembly costs can be reduced.

According to the third aspect of the present invention, in addition to the operation of the first aspect, since the initial position data of each resolver is corrected by the preset correction data, the accuracy is improved. Angle can be detected at a high level.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a resolver part of a rotation angle detecting device as a first embodiment which embodies the present embodiment.

FIG. 2 is a plan view in which a part showing a resolver portion is sectioned;

FIG. 3 is a block diagram illustrating a rotation angle detection device.

FIG. 4 is a block diagram illustrating a correction data creation device.

FIG. 5 is a graph showing RD conversion output data of each resolver.

FIG. 6 is a longitudinal sectional view showing a resolver part of the rotation angle detecting device of the second embodiment.

FIG. 7 is a plan view in which a part showing a resolver part is sectioned;

FIG. 8 is a perspective view showing stators of a one-rotation resolver and an eighteen-pole resolver.

FIG. 9 is a graph showing RD conversion output data of each resolver of a conventional example.

[Explanation of symbols]

8: one-rotation resolver, 14: 18-pole resolver as first multi-pole resolver, 20: 132-pole resolver as second multi-pole resolver, 26: first correction initial position data calculation means, first initial A pole determining unit, a first absolute data calculating unit, a second corrected initial position data calculating unit, a second initial pole determining unit, a second absolute data calculating unit, a third corrected initial position data calculating unit,
CPU as pole assignment means, third absolute data calculation means and correction position data calculation means, PROM as storage means, 41 excitation salient pole, 42 auxiliary excitation salient pole, 46 excitation salient pole, 47 ... Sub-excitation salient poles, 50 eccentric rotors as rotors, 51 multi-pole rotors as rotors, 52 single-rotation resolvers, 53 18-pole resolvers as first multi-polar resolvers, Ama [i] one rotation setting Output data as data, Bma [v]... Output data as first multipolar setting data, Cma [p]... Output data as second multipolar setting data, AK, BK, CK. BaK, CaK: Absolute data, TB
K, TCK: initial pole, EA [i], EB [v], EC
[P] ... output data as reference data, js, v
s: Absolute first multi-pole setting data, w
• t, pt: Absolute second multi-pole setting data, Ig [p]: Reference data, AKS, BKS, CKS ...
Correction initial position data, ΔAma [i]: one rotation correction data, ΔBma [v]: 18 as first multipolar correction data
Polar correction data, ΔCmap]... 132 pole correction data as second multipolar correction data, θK... Initial position, Cma (t)
... output data, TCK (t) ... pole, CaK (t) ... absolute data, CKS (t) ... correction position data.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location H02K 24/00 H02K 24/00

Claims (3)

(57) [Claims] A single-rotation detecting resolver; one or a plurality of first multi-polar resolvers having a different number of poles; and a first multi-polar resolver having a larger number of poles than the first resolver. A first multipole resolver (20), and a first initial pole index for determining an initial pole (TBK) of the first multipole resolver (14) with respect to initial position data (AK) obtained from the one-rotation detection resolver (8). Means (26)
An absolute value obtained by converting the initial position data (BK) of the first multipolar resolver (14) from the initial pole (TBK) and the initial position data (BK) obtained from the first multipolar resolver (14). First absolute data calculating means (26) for obtaining data (BaK); and second initial pole determining means (2) for determining an initial pole (TCK) of a second multipolar resolver (20) for the absolute data (BaK). 26) and absolute data (CaK) obtained by converting the initial position data (CK) into absolute data from the initial pole (TCK) and the initial position data (CK) obtained from the second multipole resolver (20). Second absolute data calculating means (26) for outputting as initial position data, and multipolar measurement data of a second multipolar resolver (20) sequentially obtained From the comparison result between Cma (t)) and the multipolar measurement data (CK) obtained before, the obtained multipole measurement data (Cma (t)) is added to the pole of the second multipole resolver (20). (T
CK (t)), the pole assignment means (26), the assigned pole (TCK (t)) and the multipole measurement data (C
and a third absolute data calculating means (26) for obtaining absolute data (CaK (t)) which has been converted into absolute data from ma (t) and outputting the obtained data as rotational position data. 2. The rotation angle detecting device according to claim 1, wherein the excitation salient pole (41) of the one-rotation detection resolver (52) is connected to the first rotation detection resolver (52).
The rotation angle detecting device, wherein the exciting salient pole (46) of the multipolar resolver (14) is provided on the same stator (40). 3. The rotation angle detecting device according to claim 1, wherein each rotation setting data (Ama [i]) obtained from said one rotation detection resolver is created. One rotation setting data (Ama [i]) is converted to first multipolar setting data (Bma) obtained from the corresponding first multipolar resolver (14).
[V]) one-rotation correction data (Δ
Ama [i]) and each first multipole setting data (Bma [j]) obtained from the first multipole resolver (14), and the first
For correcting the second multipolar setting data (Cma [p]) obtained from the corresponding second multipolar resolver (20). The pole correction data (ΔBma [v]) and each second multipole setting data (Cma [p]) obtained from the second multipole resolver (20) are created, and the second
The second multipolar correction data (ΔCma [p]) for correcting the multipolar setting data (Cma [p]) with respect to the reference data (Ig [p]) created for each corresponding rotational position )
And the one-rotation correction data (ΔAma [i]) corresponding to the initial position data (AK) is obtained, and the one-rotation correction data (ΔAma [i) is stored in the initial position data (AK). ]) To obtain the corrected initial position data (AKS) of the one-rotation detection resolver (8), and the first multiplicity corresponding to the absolute data (BaK). Polar correction data (ΔBma [v]) is obtained, and the absolute data (BaK) is added to the first multipolar correction data (ΔBma [v]).
[V]), a second corrected initial position data calculating means (26) for obtaining corrected initial position data (BKS) of the first multipolar resolver (14), and a second corrected initial position data (CaK) corresponding to the absolute data (CaK). 2 multipolar correction data (ΔCma [p]), and the absolute data (CaK) is added to the second multipolar correction data (ΔCma [p]).
[P]) and third corrected initial position data calculating means (26) for obtaining corrected initial position data (CKS) of the second multipolar resolver (20), and absolute data (CaK (t)). The corresponding second multipolar correction data (ΔCma [p]) is obtained, and the absolute value of the second multipolar correction data (ΔCma [p]) is added to the absolute data (CaK (t)). Resolver (2
0) correction position data calculation means (26) for obtaining the correction position data (CKS (t)), wherein the first initial pole indexing means (26) is provided with the first correction initial position data calculation means (26). 26) derives an initial pole (TBK) of the first multi-pole resolver (14) from the corrected initial position data (AKS) obtained by the second initial pole determining means (26). The initial pole (TCK) of the second multi-pole resolver (20) is calculated from the corrected initial position data (BKS) obtained by the position data calculating means (26), and the third corrected initial position data calculating means (26) A rotation angle detection device that outputs the calculated corrected initial position data (CKS) as rotation initial position data, and the corrected position data calculation means (26) outputs the calculated corrected position data (CKS (t)) as rotation position data. .