JP4397788B2 - Rotation angle detector - Google Patents

Description

  The present invention relates to a rotation angle detection device that detects a rotation angle of a motor or the like.

The rotation angle detector is practically used as a simple and inexpensive structure that can withstand high-temperature environments with respect to optical encoders that have a limited operating temperature environment and a complicated and expensive structure. The rotation angle is detected by utilizing the change in the permeance of the gap between the rotor and the stator.
The principle of these rotation angle detection devices is that the rotor and the stator have salient poles, and depending on the angle of the rotor, the phase of the voltage appearing on the winding wound around the salient poles of the stator or The amplitude changes, and the rotation angle of the rotor can be known by reading the change.

As shown in Patent Document 1 (particularly FIG. 1 and FIG. 3), a conventional rotation angle detection device includes a stator having an exciting coil and a rotor that changes inductance according to the rotation angle. In this rotation angle detection device, each exciting salient pole is provided with a coil, and among the exciting coils L1 to L8, L1 and L3 are connected in series to form a coil pair. Similarly, L2 and L4, L7 and L5, and L8 and L6 form a coil pair. That is, each coil is only wound around a certain salient pole, and only two of the coils are connected in series to form a coil pair (for details, see Patent Document 1). ).
However, in the above configuration, when noise is generated or when the rotor is decentered, each coil is directly affected, so that the detection accuracy of the rotation angle is deteriorated.

Japanese Patent No. 3014955

  In the conventional rotation angle detection device, each coil is directly affected by noise or eccentricity when noise occurs or the rotor is eccentric. Furthermore, since only two coils are connected in series to form a coil pair, the rotation angle detection signal is likely to be affected by noise and eccentricity, resulting in a problem that the detection position accuracy deteriorates.

  An object of the present invention is to solve the above-described problems, and an object of the present invention is to provide a rotation angle detection device that is not easily affected by noise and eccentricity and can perform highly accurate detection. Is to provide.

A rotation angle detecting device according to the present invention includes a plurality of stator salient poles formed at intervals in the circumferential direction and a plurality of excitation salients formed by winding a conductor for each stator salient pole. A stator having coils, and a rotor having a plurality of rotor salient poles facing the stator and spaced apart in the circumferential direction, and the coils of each stator salient pole are at least 3 It is connected to more than five series and groups coil is a plurality formed, when the number of rotor poles is M, the curve representing the distribution of the number of turns of wire in each coil constituting the coils, space It is expressed as the sum or difference of the Nth order sine wave and the space | N ± M | th order (where || is a symbol representing an absolute value) .

According to the rotation angle detection device of the present invention, since the coils are configured by connecting three or more coils in series, the coils cancel each other out voltage changes, and the rotor is eccentric. Sometimes, the voltage change of the coil group can be reduced.
That is, since it becomes difficult to be affected by the eccentricity of the rotor, a highly accurate rotation angle detection device can be obtained.
Moreover, since it becomes difficult to be influenced by external noise such as magnetic flux generated by an electric motor or an inverter on the same principle, a highly accurate rotation angle detection device can be obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding members and parts will be described with the same reference numerals.
Embodiment 1 FIG.
FIG. 1 is a cross-sectional view of a generator having, for example, a claw-shaped field core, to which a rotation angle detection device according to Embodiment 1 of the present invention is attached.
In FIG. 1, the AC generator for a vehicle includes a rotation angle detection device 1 that detects a rotation angle of a generator rotor 3, a shaft 2 on which a rotor 9 of the rotation angle detection device 1 is fixed at one end, A generator rotor 3 fixed to the shaft 2 and a generator stator 4 fixed to a rotating machine case 17 so as to surround the generator rotor 3 are provided.

FIG. 2 is a structural diagram of the rotation angle detection device 1 shown in FIG. Here, an example of the rotation angle detection device 1 having a stator salient pole number of 6 and an axial multiplication angle of 4 is shown.
In FIG. 2, the rotation angle detection device 1 includes a stator 6 having a stator salient pole 5 disposed inwardly in a circumferential direction, and a rotor having a rotor salient pole 8 facing the stator salient pole 5. 9. The stator salient pole 5 of the stator 6 is provided with a coil 7 around which a conducting wire is wound.
The rotation angle detection device 1 also detects an excitation power source 10 that applies an excitation voltage to the coil 7, a first voltage detection unit 11 that detects a voltage of a coil group (described later), and a voltage of the coil group. And a second voltage detector 12.

In addition, since the rotation angle detector 1 has a shaft angle multiplier of 4, the rotor 9 has four rotor salient poles 8 formed thereon. The stator 6 has a stator salient pole 5. Here, six stator salient poles 5 are arranged in the circumferential direction. In addition, each of the stator salient poles 5 is provided with six coils 7, and since there are six stator salient poles 5, a total of 36 coils 7 are formed.
Here, the number of the stator salient pole 5 is expressed as the stator salient poles 5a, 5b,. Similarly, the number of the rotor salient pole 8 is represented as the rotor salient poles 8a, 8b,.
Further, the n-th coil 7 from the outside of the m-th stator salient pole 5 to the inner diameter side is represented as a coil 7 (m, n).

Among these coils 7, for example, coils 7 (a, 1), 7 (b, 1), 7 (c, 1), 7 (d, 1), 7 (e, 1) and 7 (f, 1) Each of the conductors is wound around each stator salient pole 5 to form a coil 7, and each coil 7 is connected in series to constitute a coil group 13.
Here, the n-th coil group 13 from the outer side of a certain stator salient pole 5 to the inner diameter side is represented as 13 (n).
The detailed configuration of the coil group 13 (1) is shown in FIGS.

Similarly, the other coils 7 are connected in series to constitute a total of six coil groups 13.
That is, the coils 7 (a, 2), 7 (b, 2), 7 (c, 2), 7 (d, 2), 7 (e, 2) and 7 (f, 2) are connected in series. The coil group 13 (2) is composed of coils 7 (a, 3), 7 (b, 3), 7 (c, 3), 7 (d, 3), 7 (e, 3) and 7 (f, 3) is connected in series to constitute the coil group 13 (3).
Also, the coils 7 (a, 4), 7 (b, 4), 7 (c, 4), 7 (d, 4), 7 (e, 4) and 7 (f, 4) are connected in series. The coil group 13 (4) is configured, and the coils 7 (a, 5), 7 (b, 5), 7 (c, 5), 7 (d, 5), 7 (e, 5) and 7 (f, 5) are connected in series to form a coil group 13 (5), and coils 7 (a, 6), 7 (b, 6), 7 (c, 6), 7 (d, 6), 7 (e , 6) and 7 (f, 6) are connected in series to constitute the coil group 13 (6).

FIG. 5 is a circuit diagram showing the connection of the coil group 13 of the rotation angle detection device 1 shown in FIG.
In FIG. 5, the coil group 13 (1) and the coil group 13 (2), the coil group 13 (3) and the coil group 13 (4), and the coil group 13 (5) and the coil group 13 (6) are connected in series. The two coil groups 13 connected in series are connected in parallel and connected to the excitation power source 10 respectively.
The first voltage detector 11 is connected between the coil group 13 (1) and the coil group 13 (2) and between the coil group 13 (3) and the coil group 13 (4). The second voltage detector 12 is connected between the coil group 13 (4) and the coil group 13 (5) and the coil group 13 (6).

Note that the connecting wire that electrically connects the coils 7 may be configured to cross the core back portion of the stator 6.
In FIG. 4, when the coil group 13 is configured, the six coils 7 are connected in series. However, it is not always necessary to connect all the salient-pole coils 7 in series. 6 even if there are four such as coils 7 (a, 1), 7 (c, 1), 7 (d, 1), and 7 (f, 1) as shown in FIG. Good.

  An example of the number of turns of the conducting wire of each coil 7 is shown in FIG. For example, FIG. 7 shows that the number of turns (= −33) of the salient poles 5b of the coil group 13 (1) is the number of turns of the coils 7 (b, 1). When the winding number is negative, it indicates that the winding direction is the reverse direction.

Hereinafter, an operation of the rotation angle detection device 1 having the above-described configuration will be described.
For example, when an AC voltage of about 10 kHz is applied to the circuit by the excitation power supply 10, an AC current flows through each coil 7.
When a current flows through the coil 7, a magnetic flux is generated in the gap portion. Since the rotor 9 has salient poles, the magnetic flux changes depending on the rotational position, and the inductances of the coil 7 and the coil group 13 change. At this time, since the voltage of the voltage detector changes depending on the rotation angle of the rotor 9, the rotation angle can be detected.

FIG. 8 shows waveforms of output voltages detected by the first voltage detection unit 11 and the second voltage detection unit 12. The horizontal axis represents the rotation angle of the rotor 9, and the vertical axis represents the voltage value. In this figure, a negative voltage indicates that the phase is reversed.
FIG. 8 shows that the voltage changes in a sine wave shape according to the rotation angle. Since the two-phase output voltage waveforms are out of phase, the rotation angle can be detected.
Furthermore, when the rotation angle changes by 90 °, the waveform of the output voltage changes by one period, so that it can be confirmed that the device operates as the rotation angle detection device 1 with the shaft angle multiplier of 4.

According to the rotation angle detection device 1 according to the first embodiment of the present invention, the coil group 13 is configured by connecting three or more coils 7 in series, so noise and eccentricity of the rotor 9 occur. Even in this case, the plurality of coils 7 constituting the coil group 13 can cancel the influence of noise and eccentricity of the rotor 9.
Therefore, when the output voltage is detected by the voltage detection unit, it is difficult to be affected by noise and the eccentricity of the rotor 9, and the rotation angle can be detected with high accuracy.

Heretofore, in the case where the number of coil groups 13 is six, an example in which two coil groups 13 connected in series and three connected in parallel has been shown, but the present invention is not limited to this configuration.
FIG. 9 is a configuration diagram of the rotation angle detection device 1 according to the first embodiment of the present invention when the number of coil groups 13 is eight.
FIG. 10 is a circuit diagram showing the connection of the coil group 13 of the rotation angle detection device 1 shown in FIG.
9 and 10, eight coil groups 13 (1) to 13 (8) are configured, and the coil group 13 (1) and the coil group 13 (2), and the coil group 13 (3) and the coil group 13 are configured. (4) and coil group 13 (5) and coil group 13 (6), coil group 13 (7) and coil group 13 (8) connected in series, four in parallel, 10 is connected.
The first voltage detector 11 is connected between the coil group 13 (1) and the coil group 13 (2) and between the coil group 13 (3) and the coil group 13 (4). The second voltage detector 12 is connected between the coil group 13 (6) and the coil group 13 (7) and the coil group 13 (8).
Here, a voltage is applied by the excitation power supply 10 and the voltage is detected at two locations of the first voltage detection unit 11 and the second voltage detection unit 12 to detect the rotation angle of the rotor 9.

An example of the number of turns of the conductive wire of each coil 7 is shown in FIG. For example, in FIG. 11, the number of turns (= −33) of the salient pole 5 b of the coil group 13 (1) indicates the number of turns of the coil 7 (b, 1). When the winding number is negative, it indicates that the winding direction is the reverse direction.
Even when configured in this manner, it can be confirmed that the device operates as the rotation angle detection device 1 in the same manner as when the number of the coil groups 13 is six.

Embodiment 2. FIG.
FIG. 12 is a structural diagram of the rotation angle detection device 1 according to Embodiment 2 of the present invention. Here, an example of the rotation angle detection device 1 having 10 stator salient poles and a shaft angle multiplier of 4 is shown.
In FIG. 12, the rotor 9 takes a reference line passing through the center of the rotation axis of the rotor 9, and the angle representing the position of the outer periphery of the rotor 9 from the reference line is θ, the gap at the position of the angle θ. The length is a shape represented by the following formula (3).
1 / {A + Bcos (Mθ)} (3)
(However, A and B are positive constants, and A> B and M are shaft double angles of the rotation angle detector)

Here, the number of turns of each coil 7 will be considered for the purpose of further improving the accuracy of the rotation angle detection device 1.
Therefore, in the magnetic flux generated in the air gap, a specific spatial order (the spatial order is an order in which the spatial primary has a mechanical angle of 360 ° as one cycle, and the spatial nth order has a mechanical angle of 360 ° as an n cycle. If the coil 7 is configured to pick up the component (b), it will be less susceptible to noise and eccentricity, and it will be possible to detect the rotational position with higher accuracy.

When the spatial order of the magnetomotive force generated in the gap portion by the current flowing in each coil 7 is N and the number of the rotor salient poles 8 is M, the magnetic flux density generated in the gap portion is the space | N ± M | However, a component of || is generated.
Therefore, the distribution of the number of turns of the coil 7 provided on each salient pole of the stator 6 may be picked up in the space | N + M | and space | N−M | On the other hand, it is necessary to include a spatial Nth order component which is the spatial order of the magnetomotive force.

Therefore, it can be understood that the distribution of the number of turns of the coils 7 constituting each coil group 13 may be expressed as the sum or difference of the space N-th order sine wave and the space | N + M |
In addition, it may be expressed as the sum or difference of the space Nth-order sine wave and the space | N−M | Alternatively, it may be expressed as the sum or difference of a spatial Nth-order sine wave and a space | N + M |

  From the above consideration, when the number of salient poles of the rotor 9 is M and the number of salient poles of the stator 6 is Ns, the winding of the conductor of the j-th coil 7 from the outside of the i-th stator salient pole 5 is performed. If the number is Nij, Nij can be determined as in the following equation (4).

ここで、Ｎは上記起磁力の空間次数である。

Here, N is the spatial order of the magnetomotive force.

In FIG. 12, as a specific example, a case where the number of salient poles Ns of the stator 6 is 10 and the number of salient poles of the rotor 9 is 4 is shown. The stator 6 has ten salient poles, and a coil 7 is formed by winding a conductive wire around each salient pole.
Coils 7 (a, 1), 7 (b, 1), 7 (c, 1), 7 (d, 1), 7 (e, 1), 7 (f, 1), 7 (g, 1), 7 (h, 1), 7 (i, 1) and 7 (j, 1) are connected in series to constitute the coil group 13 (1). Further, as shown in FIG. 5, six coil groups 13 are connected to constitute a circuit. The rotor 9 has four salient poles.

FIG. 13 shows an example in which the number of turns of each coil 7 is determined based on the equation (4). However, Nf = 5, N1 = 20, N2 = 0, and the numbers after the decimal point are rounded off.
For αij, α1j = 0, α2j = 180 °, α3j = 90 °, α4j = 270 °, α5j = 180 °, α6j = 0 °, and βij was arbitrary.
In FIG. 13, when the number of turns is negative, it indicates that the winding direction is the reverse direction. For example, in FIG. 13, the number of turns (= 11) of the salient poles 5b of the coil group 13 (1) indicates the number of turns of the coils 7 (b, 1).

The waveform of the output voltage at this time is shown in FIG. The horizontal axis represents the rotation angle, and the vertical axis represents the output voltage waveform. Since the output voltage waveform becomes one cycle at a rotation angle of 90 °, it can be confirmed that the device operates as the rotation angle detection device 1 with a shaft angle multiplier of 4.
Further, even when the coil group 13 shown in FIG.

According to the rotation angle detection device 1 according to the second embodiment of the present invention, since the coil 7 picks up a specific spatial order component in the magnetic flux generated in the air gap, noise and the rotor 9 Even when the eccentricity occurs, the plurality of coils 7 constituting the coil group 13 can cancel the influence of noise and the eccentricity of the rotor 9. A highly accurate rotation angle detection device 1 can be obtained.
Note that the distribution of the number of turns of the conducting wire of the coil 7 constituting each coil group 13 does not need to be strictly a sine wave, and the same effect can be obtained when it is expressed by a function close thereto.

  Further, when the origin of the rotation axis of the rotor 9 is the origin and the angle representing the position of the outer periphery of the rotor 9 is θ, the gap length at the angle θ is expressed by the equation (3). Therefore, the permeance change of the air gap becomes a sine wave, and the rotation angle detection device 1 with high accuracy can be obtained.

  Note that the winding number distribution does not have to be strictly a function expressed by the equation (4), and the same effect can be obtained when expressed by a function close to that. In addition, if the expression (4) is strictly followed, the number of turns may be a decimal number, but the same effect can be obtained when an integer obtained by rounding off the decimal point or rounding off the decimal point is used.

Here, a method for determining αij and βij and a method for connecting the coil 7 will be described.
When the coil group 13 is composed of six pieces as shown in FIG. 5, the coil group 13 (1) and the coil group 13 (2) are 180 ° out of phase with each other in order to operate as the rotation angle detection device 1. Thus, the coil group 13 (3) and the coil group 13 (4) are 180 degrees out of phase with each other, and the coil group 13 (5) and the coil group 13 (6) are 180 degrees out of phase with each other. It is necessary to set the number of turns of the conductor. That is, the phases of the two coil groups 13 connected in series are shifted by 180 °. Furthermore, the coil groups 13 connected in parallel need to be 90 ° out of phase with each other.

Therefore, in the configuration of FIG. 4, for example, in the coil group 13 (1), α11 and β11 are arbitrary constants,
α11 = α12 = α13 =... = α1Ns
β11 = β12 = β13 =... = β1Ns
In the coil group 13 (2),
α21 = α22 = α23 =... = α2Ns = α11 + π
β21 = β22 = β23 =... = β2Ns = β11 + π
In the coil group 13 (3),
α31 = α32 = α33 =... = α3Ns = α11 + π / 2
β31 = β32 = β33 = ... = β3Ns = β11 + π / 2
In the coil group 13 (4), α41 = α42 = α43 =... = Α4Ns = α11 + 3π / 2
β41 = β42 = β43 =... = β4Ns = β11 + 3π / 2
In the coil group 13 (5), α51 = α52 = α53 =... = Α5Ns = α11 + π
β51 = β52 = β53 = ... = β5Ns = β11 + π
In the coil group 13 (6), α61 = α62 = α63 =... = Α6Ns = α11
β61 = β62 = β63 =... = β6Ns = β11
And it is sufficient.
However, for example, α11 + π / 2 is equivalent to α11 + π / 2 + 2mπ (m is an arbitrary integer), and thus does not necessarily follow the above formula.

The coil group 13 is connected by, for example, connecting the coil group 13 (1) and the coil group 13 (2) in series, and connecting the coil group 13 (3) and the coil group 13 (4) in series. The coil group 13 (5) and the coil group 13 (6) are connected in series.
Further, the other end of the coil group 13 (1), the other end of the coil group 13 (3), and the other end of the coil group 13 (5) are all connected to serve as a first excitation input end.
Further, the other end of the coil group 13 (2), the other end of the coil group 13 (4), and the other end of the coil group 13 (6) are all connected to serve as a second excitation input end.
The connection point between the coil group 13 (1) and the coil group 13 (2) is a first output terminal, and the connection point between the coil group 13 (3) and the coil group 13 (4) is a second output terminal. And the connection point between the coil group 13 (5) and the coil group 13 (6) is the third output terminal, the voltage difference between the first output terminal and the second output terminal is the first output signal, The voltage difference between the output terminal and the third output terminal may be used as the second output signal.

In the case of the eight coil groups 13 in FIG. 7, the coil group 13 (3) and the coil group 13 are arranged so that the coil group 13 (1) and the coil group 13 (3) are 180 ° out of phase with each other. The coil group 13 (7) and the coil group 13 (8) so that the phase of the coil group 13 (5) and the coil group 13 (6) are 180 degrees out of phase with each other (4). ) Is set so that the number of turns of the conducting wire is 180 ° out of phase with each other. That is, the phases of the two coil groups 13 connected in series are shifted by 180 °.
In addition, the coil group 13 connected in parallel has a phase difference of 180 ° between the coil groups 13 (1) and 13 (2) and the coil groups 13 (3) and 13 (4), and the coil groups 13 (5) and 13 (13). (6) and the coil groups 13 (7) and 13 (8) are 180 degrees out of phase with each other, and the coil groups 13 (1) and 13 (2) and the coil groups 13 (5) and 13 (6) Need to be 90 ° out of phase with each other.

Therefore, in the configuration of FIG.
In the coil group 13 (1), α11 and β11 are arbitrary constants,
α11 = α12 = α13 =... = α1Ns
β11 = β12 = β13 =... = β1Ns
In the coil group 13 (2),
α21 = α22 = α23 =... = α2Ns = α11 + π
β21 = β22 = β23 =... = β2Ns = β11 + π
In the coil group 13 (3),
α31 = α32 = α33 =... = α3Ns = α11 + π
β31 = β32 = β33 = ... = β3Ns = β11 + π
In the coil group 13 (4),
α41 = α42 = α43 = ... = α4Ns = α11
β41 = β42 = β43 = ... = β4Ns = β11
In the coil group 13 (5),
α51 = α52 = α53 =... = α5Ns = α11 + π / 2
β51 = β52 = β53 = ... = β5Ns = β11 + π / 2
In the coil group 13 (6),
α61 = α62 = α63 =... = α6Ns = α11 + 3π / 2
β61 = β62 = β63 = ... = β6Ns = β11 + 3π / 2
In the coil group 13 (7),
α71 = α72 = α73 =... = α7Ns = α11 + 3π / 2
β71 = β72 = β73 =... = β7Ns = β11 + 3π / 2
In the coil group 13 (8),
α81 = α82 = α83 =... = α8Ns = α11 + π / 2
β81 = β82 = β83 =... = β8Ns = β11 + π / 2
And it is sufficient.
However, for example, α11 + π / 2 is equivalent to α11 + π / 2 + 2mπ (m is an arbitrary integer), and thus does not necessarily follow the above formula.

In addition, about the method of the connection of the coil group 13, the coil group 13 (1) and the coil group 13 (2) are connected in series, the coil group 13 (3) and the coil group 13 (4) are connected in series, The coil group 13 (5) and the coil group 13 (6) are connected in series, and the coil group 13 (7) and the coil group 13 (8) are connected in series.
In addition, the other end of the coil group 13 (1), the other end of the coil group 13 (3), the other end of the coil group 13 (5), and the other end of the coil group 13 (7) are all connected. Is the first excitation input end.
Further, the other end of the coil group 13 (2), the other end of the coil group 13 (4), the other end of the coil group 13 (6), and the other end of the coil group 13 (8) are all connected. Is the second excitation input end.
The connection point between the coil group 13 (1) and the coil group 13 (2) is a first output terminal, and the connection point between the coil group 13 (3) and the coil group 13 (4) is a second output terminal. The connection point between the coil group 13 (5) and the coil group 13 (6) is the third output terminal, and the connection point between the coil group 13 (7) and the coil group 13 (8) is the fourth output terminal. The voltage difference between the first output terminal and the second output terminal may be the first output signal, and the voltage difference between the third output terminal and the fourth output terminal may be the second output signal.

Embodiment 3 FIG.
FIG. 15 is a structural diagram of the rotation angle detection device 1 according to Embodiment 3 of the present invention. Here, an example of the rotation angle detection device 1 in which the number of stator salient poles is 10, the shaft double angle is 2, and the number of coil groups 13 is 6 is shown.
In FIG. 15, connection portions of the coils 7 forming the coil group 13 are omitted. Ten stator salient poles 5 are arranged on the stator 6, and a conductive wire is wound around each stator salient pole 5 to form a coil 7. Each coil 7 forms a coil group 13, and the coil group 13 is connected as shown in FIG.
Although FIG. 15 shows a configuration in which six coils 7 are arranged in the radial direction, a configuration in which the coils 7 are wound in an overlapping manner may be used. On the other hand, since the rotor 9 has a shaft angle multiplier of 2, the rotor 9 has a structure having two salient poles.

  The number of turns of the coil 7 was set according to the following equation (5) where N = 5, M = 2, Ns = 10, and N2 = 0 in equation (4).

  FIG. 16 shows an output voltage waveform (envelope only) with respect to the rotation angle of the rotor 9. A waveform of one cycle is drawn at a mechanical angle of 180 °, and it can be confirmed that the device operates as the rotation angle detection device 1 with a shaft angle multiplier of 2.

  According to the rotation angle detection device 1 according to Embodiment 3 of the present invention, since the coil 7 picks up a specific spatial order component in the magnetic flux generated in the air gap, noise and the rotor 9 Even when the eccentricity occurs, the plurality of coils 7 constituting the coil group 13 can cancel the influence of noise and the eccentricity of the rotor 9. There exists an effect that the highly accurate rotation angle detection apparatus 1 can be obtained.

Embodiment 4 FIG.
FIG. 17 is a structural diagram of a rotation angle detection device 1 according to Embodiment 4 of the present invention. Here, an example of the rotation angle detection device 1 having 10 stator salient poles, 3 shaft angle multipliers, and 6 coil groups 13 is shown.
In FIG. 17, connection portions of the coils 7 forming the coil group 13 are omitted. Ten stator salient poles 5 are arranged on the stator 6, and a conductive wire is wound to form a coil 7. Each coil 7 forms a coil group 13, and the coil group 13 is connected as shown in FIG.
17 shows a configuration in which six coils 7 are arranged in the radial direction, a configuration in which the coils 7 are wound in an overlapping manner may be used. On the other hand, since the rotor 9 has a shaft angle multiplier of 3, the rotor 9 has a structure having three salient poles.

  The number of turns of the coil 7 was set according to the following equation (6) where N = 5, M = 3, Ns = 10, and N2 = 0 in equation (4).

  FIG. 18 shows an output voltage waveform (envelope only) with respect to the rotation angle of the rotor 9. A waveform of one cycle is drawn at a mechanical angle of 120 °, and it can be confirmed that the device operates as the rotation angle detection device 1 with a shaft angle multiplier of 3.

  According to the rotation angle detection device 1 according to Embodiment 4 of the present invention, since the coil 7 picks up a specific spatial order component in the magnetic flux generated in the air gap, noise and the rotor 9 Even when the eccentricity occurs, the plurality of coils 7 constituting the coil group 13 can cancel the influence of noise and the eccentricity of the rotor 9. There exists an effect that the highly accurate rotation angle detection apparatus 1 can be obtained.

Embodiment 5 FIG.
FIG. 19 is a structural diagram of the rotation angle detection device 1 according to the fifth embodiment of the present invention. Here, an example of the rotation angle detection device 1 having 10 stator salient poles, 8 shaft angle multipliers, and 6 coil groups 13 is shown.
In FIG. 19, connection portions of the coils 7 forming the coil group 13 are omitted. Ten stator salient poles 5 are arranged on the stator 6, and a conductive wire is wound to form a coil 7. Each coil 7 forms a coil group 13, and the coil group 13 is connected as shown in FIG.
Further, although FIG. 19 shows a configuration in which six coils 7 are arranged in the radial direction, a configuration in which the coils 7 are wound in an overlapping manner may be used. On the other hand, since the rotor 9 has an axial multiplication angle of 8, the rotor 9 has a structure having eight salient poles.

  The number of turns of the coil 7 was set according to the following equation (7) where N = 5, M = 8, Ns = 10, and N2 = 0 in equation (4).

  FIG. 20 shows a waveform of the output voltage (only the envelope) with respect to the rotation angle of the rotor 9. A waveform of one cycle is drawn at a mechanical angle of 45 °, and it can be confirmed that the device operates as the rotation angle detection device 1 with a shaft angle multiplier of 8.

  According to the rotation angle detection device 1 according to the fifth embodiment of the present invention, since the coil 7 picks up a specific spatial order component in the magnetic flux generated in the air gap, noise and the rotor 9 Even when the eccentricity occurs, the plurality of coils 7 constituting the coil group 13 can cancel the influence of noise and the eccentricity of the rotor 9. There exists an effect that the highly accurate rotation angle detection apparatus 1 can be obtained.

Embodiment 6 FIG.
FIG. 21 is a circuit diagram showing another connection example of the coil group 13 according to Embodiment 6 of the present invention.
In FIG. 21, the coil group 13 (1), the coil group 13 (2), and the coil group 13 (3) are shifted from each other by 120 °, and the coil group 13 (4), the coil group 13 (5), and The coil group 13 (6) is connected in series with the number of turns of the conducting wire set so that the phases thereof are shifted from each other by 120 °.
Further, the coil groups 13 (1), 13 (2), 13 (3) and the coil groups 13 (4), 13 (5), 13 (6) connected in series with each other are 180 degrees out of phase with each other. Are connected in parallel, and each is connected to the excitation power source 10.
The first voltage detector 11 is connected between the coil group 13 (1) and the coil group 13 (2), and between the coil group 13 (4) and the coil group 13 (5). The second voltage detector 12 is connected between the coil group 13 (3) and the coil group 13 (5) and the coil group 13 (6).

So far, the configuration has been described in which two coil groups 13 composed of a plurality of coils 7 are connected in series, and two further connected circuits in series are connected in parallel. However, the circuit configuration of the present invention is not limited thereto.
FIG. 21 shows an example in which three coil groups 13 are connected in series, and two three coil groups 13 connected in series are connected in parallel.
Even in such a configuration, the rotation angle can be detected by the voltage waveforms of the first voltage detection unit 11 and the second voltage detection unit 12.

The phase relationship of the coil 7 to be connected is not limited to the above, but may be connected as follows.
For example, in FIG. 21, the coil group 13 (1) and the coil group 13 (2) are 90 ° out of phase with each other, and the coil group 13 (2) and the coil group 13 (3) are 135 with each other. The number of turns of the conducting wire is set so that the phase is shifted, and they are connected in series.
In addition, the coil group 13 (4) and the coil group 13 (5) are 90 ° out of phase with each other, and the coil group 13 (5) and the coil group 13 (6) are 135 ° out of phase with each other. Thus, the number of turns of the conducting wire is set and connected in series.
The coil groups 13 (1), 13 (2), 13 (3) and the coil groups 13 (4), 13 (5), 13 (6) are connected in parallel so that they are 180 ° out of phase with each other. It is.

Embodiment 7 FIG.
FIG. 22 is a structural diagram of the rotation angle detection device 1 according to the seventh embodiment of the present invention. Here, an example of the rotation angle detection device 1 having 12 stator salient poles and a shaft angle multiplier of 5 is shown.
FIG. 23 is a structural diagram of the rotation angle detection device 1 according to the seventh embodiment of the present invention. Here, an example of the rotation angle detection device 1 having 12 stator salient poles and a shaft multiple angle of 7 is shown.
22 and 23, the number of stator salient poles 5 is 12, and the shaft angle multiplier is 5 and 7, respectively.
Even when configured in this manner, it can be confirmed that the device operates as the rotation angle detection device 1 in the same manner as described in the above embodiments.
In this case, it is particularly useful for detecting the rotation angles of the 10-pole motor and the 14-pole motor, respectively.

Embodiment 8 FIG.
The rotation angle detection device 1 as described above is cheaper and more environmentally resistant than an optical encoder. Therefore, if it is used as a rotation angle sensor such as a motor or a generator, it is cheaper and environmentally resistant. An excellent system can be constructed.
For example, it is conceivable to incorporate the rotation angle detection device 1 of the present invention in a vehicle belt drive type MG (Motor And Generator).
In the belt-driven MG system, the generator (which also operates as a motor) is disposed in the engine room, so the temperature becomes high and the optical encoder is not suitable. Moreover, it becomes expensive as a system. Therefore, if the rotation angle detection device 1 of the present invention composed of an iron core and a winding is used, it is possible to construct an inexpensive system with excellent environmental resistance.

  FIG. 1 shows a view in which a rotation angle detector 1 of the present invention is incorporated in a generator having a claw-shaped field core. Since this configuration is shown in Embodiment Mode 1, description thereof is omitted.

FIG. 24 is an explanatory diagram showing the magnetomotive force of the field winding when the rotation angle detection device 1 according to the eighth embodiment of the present invention is applied to a generator having a claw-shaped field iron core.
In FIG. 24, the generator having the claw-shaped field iron core generates a magnetomotive force 15 on the shaft 2 by the field current 14 flowing in the circumferential direction of the shaft 2, and the rotation angle detection device 1 is fixed by the magnetomotive force 15. A zero-order magnetomotive force is generated in the gap between the child salient pole 5 and the rotor salient pole 8.
Therefore, a magnetic flux 16 having the same spatial order as the shaft angle multiplier is generated in the air gap, and in the conventional technique, the output winding picks up this component, leading to an increase in detection position error.
However, as shown in the second embodiment of the present invention, in the present invention, since the winding is configured so as to pick up only a specific order component, an increase in detection position error can be prevented.

FIG. 25 shows a comparison between the conventional example and the present invention regarding the influence of the zero-order magnetomotive force of the electric motor on the output voltage. Although the waveform is disturbed in the conventional example, a sinusoidal envelope is drawn in the present invention. This indicates that the present invention is less affected by the magnetomotive force 15 of the field winding of the electric motor than the conventional example, and operates as a highly accurate rotation angle detection device 1.
FIG. 26 shows a detected position error when the rotor 9 is eccentric. From FIG. 26, it can be seen that the present invention has a smaller detection position error than the conventional example, and operates as a highly accurate rotation angle detection device 1.

According to the rotation angle detection device 1 according to the eighth embodiment of the present invention, the coil 7 picks up a specific spatial order component in the magnetic flux 16 generated in the air gap. It is difficult to be influenced by the magnetomotive force of the winding, and an increase in detection position error can be prevented, so that a highly accurate rotation angle detection device 1 can be obtained.
Even when the eccentricity of the rotor 9 occurs, the plurality of coils 7 constituting the coil group 13 can cancel the influence of noise and the eccentricity of the rotor 9.

  Here, the generator, which is a rotating electrical machine having a claw-shaped field core, has been described. However, in general motors and generators, which are other rotating electrical machines, a zero-order magnetomotive force may be generated. By using the rotation angle detection device 1 of the present invention, an increase in detection position error can be prevented.

It is sectional drawing of the generator which has the field iron core of a nail | claw shape to which the rotation angle detection apparatus which concerns on Embodiment 1 of this invention is attached. FIG. 2 is a structural diagram of the rotation angle detection device shown in FIG. 1. Here, an example of a rotation angle detection device having six stator salient poles, four shaft angle multipliers, and six coil groups is shown. It is explanatory drawing which extracts the coil which comprises the coil group of the rotation angle detection apparatus shown in FIG. 2, and abbreviate | omitted other coils. It is explanatory drawing which extracts and shows only the coil group shown in FIG. It is a circuit diagram which shows the connection of the coil group of the rotation angle detection apparatus shown in FIG. FIG. 2 is an explanatory diagram showing that a coil group is configured by connecting four coils in series in the rotation angle detection device shown in FIG. 1. FIG. 3 is a relationship diagram illustrating a relationship between a coil of the rotation angle detection device illustrated in FIG. 2 and the number of turns of a conducting wire. It is explanatory drawing which shows the measurement result of the rotation angle detection apparatus which concerns on Embodiment 1 of this invention. It is a block diagram in case the number of coil groups is eight of the rotation angle detection apparatus which concerns on Embodiment 1 of this invention. It is a circuit diagram which shows the connection of the coil group of the rotation angle detection apparatus shown in FIG. FIG. 10 is a relationship diagram illustrating a relationship between a coil and the number of turns of a conducting wire of the rotation angle detection device illustrated in FIG. 9. It is a block diagram of the rotation angle detection apparatus which concerns on Embodiment 2 of this invention. Here, an example of a rotation angle detection device having 10 stator salient poles and a shaft angle multiplier of 4 is shown. FIG. 13 is a relationship diagram illustrating a relationship between the coil illustrated in FIG. 12 and the number of turns of a conductive wire. It is explanatory drawing which shows the measurement result of the rotation angle detection apparatus which concerns on Embodiment 2 of this invention. It is a block diagram of the rotation angle detection apparatus which concerns on Embodiment 3 of this invention. Here, an example of a rotation angle detection device having 10 stator salient poles, 2 shaft angle multipliers, and 6 coil groups is shown. It is explanatory drawing which shows the measurement result of the rotation angle detection apparatus which concerns on Embodiment 3 of this invention. It is a block diagram of the rotation angle detection apparatus which concerns on Embodiment 4 of this invention. Here, an example of a rotation angle detection device having 10 stator salient poles, 3 shaft angle multipliers, and 6 coil groups is shown. It is explanatory drawing which shows the measurement result of the rotation angle detection apparatus which concerns on Embodiment 4 of this invention. It is a structural diagram of the rotation angle detection device according to Embodiment 5 of the present invention. Here, an example of a rotation angle detection device having 10 stator salient poles, 8 shaft angle multipliers, and 6 coil groups is shown. It is explanatory drawing which shows the measurement result of the rotation angle detection apparatus which concerns on Embodiment 2 of this invention. It is a circuit diagram which shows the other example of a connection of the coil group which concerns on Embodiment 6 of this invention. It is a block diagram of the rotation angle detection apparatus which concerns on Embodiment 7 of this invention. Here, an example of a rotation angle detecting device having 12 stator salient poles and a shaft multiple angle of 5 is shown. It is a block diagram of the rotation angle detection apparatus which concerns on Embodiment 7 of this invention. Here, an example of a rotation angle detecting device having 12 stator salient poles and a shaft multiple angle of 7 is shown. It is explanatory drawing which shows the magnetomotive force of a field winding at the time of applying the rotation angle detection apparatus which concerns on Embodiment 8 of this invention to the generator which has a nail | claw-shaped field iron core. It is explanatory drawing which shows the influence which a magnetomotive force exerts on an output voltage at the time of applying the rotation angle detection apparatus which concerns on Embodiment 8 of this invention to the generator which has a nail | claw-shaped field iron core compared with a prior art example. is there. Compared with the conventional example, the influence of the eccentricity of the rotor 9 on the error of the detection position when the rotation angle detection device according to the eighth embodiment of the present invention is applied to a generator having a claw-shaped field core. It is explanatory drawing shown.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Rotation angle detection apparatus, 2 axis | shafts, 5 stator salient poles, 6 stators, 7 coils, 8 rotor salient poles, 9 rotors, 13 coil groups.

Claims (7)

A stator having a plurality of stator salient poles formed at intervals in the circumferential direction and a plurality of exciting coils formed by winding a conductor for each stator salient pole;
A rotor having a plurality of rotor salient poles formed opposite to the stator and spaced in the circumferential direction;
At least three or more coils of each of the stator salient poles are connected in series to form a plurality of coil groups ,
When the number of the rotor salient poles is M, a curve representing the distribution of the number of turns of the conductive wire of each of the coils constituting the coil group is expressed as a space N-order sine wave and a space | N ± M | However, || is expressed as the sum or difference of the sine wave of ||   The rotation angle detecting device according to claim 1, wherein the coil group is formed by connecting the coils of all the adjacent stator salient poles.   The rotation angle detection device according to claim 1, wherein the coil group is formed by continuously winding a single conducting wire. When the number of the rotor salient poles is M and the number of the stator salient poles is Ns, when the coil at the outermost periphery of one stator salient pole is used as a reference, the reference coil extends in the circumferential direction. The coil wound around the j th stator salient pole, and the number of turns Nij of the i th coil conducting wire on the inner diameter side is expressed by the following equation (1)

Rotation angle detecting device according to claim 1 to any one of claims 3, wherein in represented it. The coil groups are connected in series with a phase difference of 180 ° between the coil groups, and are connected in parallel with a phase difference of 90 ° between the coil groups. Item 5. The rotation angle detection device according to any one of items 4 to 6. A straight line passing through one vertex of the rotor salient pole and the center of the rotation axis of the rotor is a reference line, the reference line, and the vertex of the stator salient pole closest to the reference line and the rotation axis When the angle on the apex side of the rotor salient pole is an angle θ, the gap length L between the apex of the stator salient pole and the rotor at the angle θ Is the following equation (2)
L = 1 / {A + Bcos (Mθ)} (2)
(Here, A and B are positive constants, and A> B and M are shaft angle multipliers of the rotation angle detector).
Rotation angle detecting device according to claim 1 to any one of claims 5, wherein in represented it. The said rotation angle detection apparatus of any one of Claim 1 to 6 with which the said rotor is attached to the edge part of the axis | shaft of a rotary electric machine.

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