JP2019071712A - Motor controller and motor system - Google Patents

Abstract

To provide a motor controller and a motor system that improve reliability of motor control.SOLUTION: A motor controller comprises: a rotary body; a sensor part which detects a rotational angle of the rotary body; a rotational angle detection device 1 which has a first signal generation part converting information associated with the rotational angle detected by the sensor part into a first signal and outputting it, and a second signal generation part converting information associated with the rotational angle detected by the sensor part into a second signal and outputting it; and a signal comparison part 52 which compares the first signal output from the first signal generation part with the second signal output from the second signal generation part.SELECTED DRAWING: Figure 14

Description

  The present invention relates to a motor control device and a motor system.

  As a motor for driving an automobile such as an electric power steering apparatus, a rotation angle detection device is used which detects a relative angle or an absolute angle of a rotation angle detection target. For example, in Patent Document 1, a rotating body in which magnetic poles aligned at equal intervals are provided in a concentric ring shape and a plurality of magnetic tracks having different numbers of magnetic poles are formed, and magnetic fields of these magnetic tracks are detected Describes a rotation detection device comprising a plurality of magnetic sensors.

JP 2008-233069 A

  For example, it is desired to further improve the reliability of motor control of a motor for driving a car.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a motor control device and a motor system in which the reliability of motor control is improved.

  In order to achieve the above object, a motor control device according to one aspect includes a rotating body attached to a motor, a sensor unit that detects a rotation angle of the rotating body, and information on the rotation angle detected by the sensor unit Rotation angle having a first signal generation unit that converts the first signal into a first signal, and a second signal generation unit that converts information on the rotation angle detected by the sensor unit into a second signal and outputs the second signal. And a signal comparison unit that compares the first signal output from the first signal generation unit with the second signal output from the second signal generation unit. According to this, the rotation angle detection device can determine the presence or absence of abnormality in the first signal and the second signal based on the comparison result by the signal comparison unit.

  Preferably, the first signal and the second signal have different signal types. According to this, the presence or absence of abnormality can be determined for the first signal and the second signal which have different signal types.

  As a desirable mode, the first signal is an ABZ signal, the second signal is a serial signal, and a counter which detects a pulse waveform in the ABZ signal to generate a count value of the ABZ signal, further comprising: The signal comparison unit compares the count value with the serial signal. According to this, the presence or absence of abnormality can be determined for the ABZ signal and the serial signal.

  As a desirable aspect, the rotation angle detection device further includes a first output port that outputs the first signal, and a second output port that outputs the second signal. According to this, the rotation angle detection device can output the first signal and the second signal indicating the same rotation angle within the same period (for example, simultaneously or substantially simultaneously).

  As a desirable mode, the rotating body has a plurality of magnetic tracks whose magnetic pole pairs consisting of an N pole and an S pole are arranged in a concentric ring at equal intervals and the number of magnetic pole pairs is different from each other; A plurality of magnetic sensors that detect a magnetic field of a magnetic track and output a sin signal and a cos signal, and the rotation angle detection device calculates a phase of the sin signal and the cos signal, and a plurality of phase detection units A phase difference detection unit that calculates the phase difference between the phases, and an angle calculation unit that calculates an absolute angle of the rotating body based on the phase difference, wherein the first signal generation unit The information on the absolute angle calculated by the calculation unit is converted into the first signal and output, and the second signal generation unit outputs the information on the absolute angle calculated by the angle calculation unit to the second signal Conversion and output. According to this, the first signal generator can generate an ABZ signal indicating an absolute angle as the first signal. The second signal generator may generate a serial signal indicating an absolute angle as the second signal. The signal comparison unit can compare the absolute angle indicated by the ABZ signal with the absolute angle indicated by the serial signal.

  As a desirable mode, it further has a control part which controls rotation operation of the above-mentioned motor based on a comparison result by the above-mentioned signal comparison part. According to this, the motor control device can determine the presence or absence of abnormality in the first signal and the second signal based on the comparison result by the signal comparison unit. Then, when an abnormality is detected in the first signal or the second signal, the motor control device can stop the motor, for example.

  As a desirable mode, when it is judged by the comparison result that the rotation angle indicated by the first signal matches the rotation angle indicated by the second signal, the control unit controls the motor in the first mode. When it is determined that the rotation angle indicated by the first signal and the rotation angle indicated by the second signal do not match, according to the comparison result. The motor is controlled in a second different mode. According to this, it is possible to further improve the reliability of motor control.

  A motor system according to one aspect includes a motor and a motor control device that controls the motor, and the motor control device includes a rotating body attached to the motor and a sensor unit that detects a rotation angle of the rotating body. A first signal generation unit that converts information on the rotation angle detected by the sensor unit into a first signal and outputs the first signal, and converts information on the rotation angle detected by the sensor unit into a second signal Of the first signal output from the first signal generator and the second signal output from the second signal generator. And a signal comparison unit. According to this, the motor system can determine the presence or absence of abnormality in the first signal and the second signal based on the comparison result by the signal comparison unit. Then, when it is determined that the first signal or the second signal is abnormal, the motor system can stop the motor, for example.

  According to the present invention, it is possible to provide a motor control device and a motor system in which the reliability of motor control is improved.

FIG. 1 is a diagram illustrating an example of a rotation angle detection device according to a first embodiment. FIG. 2 is a view showing an example of a rotating body of the rotation angle detecting device according to the first embodiment. FIG. 3 is a view showing an example of each magnetic track of the rotating body shown in FIG. FIG. 4 is a view showing another example of each magnetic track of the rotating body shown in FIG. FIG. 5 is a view showing an arrangement example of the magnetic sensor module of the rotation angle detection device according to the first embodiment. 6 is a cross-sectional view taken along the line IV-IV shown in FIG. 5 of the rotation angle detection device according to the first embodiment. FIG. 7 is a view showing an example of each magnetic sensor of the rotation angle detection device according to the first embodiment. FIG. 8 is a diagram showing an example of each waveform of the rotation angle detection device according to the first embodiment. FIG. 9 is a diagram showing an example of each waveform of the rotation angle detection device according to the first embodiment. FIG. 10 is a table showing an example of the serial signal and the ABZ signal. FIG. 11 is a table showing an example of the serial signal and the ABZ signal. FIG. 12 is a diagram illustrating an example of a transmission mode of serial signals. FIG. 13 is a flowchart illustrating an example of a method of detecting an absolute angle by the rotation angle detection device according to the first embodiment. FIG. 14 is a diagram illustrating an example of the motor system according to the first embodiment. FIG. 15 is a flowchart illustrating an example of a motor control method by the motor system according to the first embodiment. FIG. 16 is a diagram illustrating an example of a motor system according to the second embodiment. FIG. 17 is a diagram illustrating an example of a motor system according to the third embodiment.

  Hereinafter, modes for carrying out the invention (hereinafter referred to as embodiments) will be described in detail with reference to the drawings. Note that the present invention is not limited by the following embodiments. Further, constituent elements in the following embodiments include those which can be easily conceived by those skilled in the art, those substantially the same, and so-called equivalent ranges. Furthermore, the components disclosed in the following embodiments can be combined as appropriate.

(Embodiment 1)
FIG. 1 is a diagram illustrating an example of a rotation angle detection device according to a first embodiment. As shown in FIG. 1, the rotation angle detection device 1 according to the first embodiment includes a rotating body 100 having a first magnetic track 2A and a second magnetic track 2B, a magnetic sensor module 200, and a storage unit 10. . The magnetic sensor module 200 includes a first magnetic sensor 3A, a second magnetic sensor 3B, a first phase detector 5A, a second phase detector 5B, a phase difference detector 6, an angle calculator 7, and a signal. The generation unit 8 includes a first output port P1, a second output port P2, and a third output port P3. Further, the signal generation unit 8 includes a first signal generation unit 8A and a second signal generation unit 8B.

  In the present embodiment, the magnetic sensor module 200 is integrated into, for example, one IC chip. As a result, the number of parts constituting the rotation angle detection device 1 can be reduced, the positional accuracy between the first magnetic sensor 3A and the second magnetic sensor 3B can be improved, and the manufacturing cost and the assembly cost can be reduced. A small and inexpensive rotation angle detection device 1 can be realized. The magnetic sensor module 200 may include, for example, the storage unit 10. Thereby, further miniaturization and cost reduction of the rotation angle detection device 1 can be realized.

  FIG. 2 is a view showing an example of a rotating body of the rotation angle detecting device according to the first embodiment. FIG. 3 is a view showing an example of each magnetic track of the rotating body shown in FIG. FIG. 4 is a view showing another example of each magnetic track of the rotating body shown in FIG. FIG. 5 is a view showing an arrangement example of the magnetic sensor module of the rotation angle detection device according to the first embodiment. 6 is a cross-sectional view taken along the line IV-IV shown in FIG. 5 of the rotation angle detection device according to the first embodiment. FIG. 7 is a view showing an example of each magnetic sensor of the rotation angle detection device according to the first embodiment.

  As shown in FIG. 2 or FIG. 3, in the rotor 100 of the first embodiment, the first magnetic track 2A in which magnetic pole pairs 2A1 consisting of N and S poles are equally spaced and the magnetic pole pairs 2B1 are equally spaced The second magnetic tracks 2B and the second magnetic tracks 2B are arranged in a radial direction in a concentric ring shape with the rotation axis X of the rotating body 100 as an axis. The first magnetic track 2A and the second magnetic track 2B of the first embodiment are obtained, for example, by alternately magnetizing one end face in the axial direction of the rotating body 100 to the N pole and the S pole at equal intervals in the circumferential direction. Be Specifically, in the first magnetic track 2A and the second magnetic track 2B, for example, magnetic poles different in the circumferential direction are alternately arranged such that the portion shaded in the figure is the N pole and the portion without the mesh is the S pole. It is distributed at equal intervals. In the example shown in FIG. 3, the first magnetic track 2A has 12 pairs of magnetic pole pairs 2A1. The second magnetic track 2B also has eight pairs of magnetic pole pairs 2B1.

  In the present embodiment, the relationship between the number of magnetic pole pairs 2A1 of the first magnetic track 2A and the number of magnetic pole pairs 2B1 of the second magnetic track 2B is not limited to the example shown in FIG. As shown in FIG. 4, the first magnetic track 2A may have 32 pole pairs 2A1. Also, the second magnetic track 2B may have 31 pairs of magnetic pole pairs 2B1. That is, when the number of magnetic pole pairs 2A1 of the first magnetic track 2A is P (P is a natural number), the number of magnetic pole pairs 2B1 of the second magnetic track 2B may be P-1. Although not shown, when the number of magnetic pole pairs 2A1 of the first magnetic track 2A is P, the number of magnetic pole pairs 2B1 of the second magnetic track 2B may be P + 1. When the number of pole pairs 2A1 of the first magnetic track 2A is P and the number of pole pairs 2B1 of the second magnetic track 2B is P-1 (or P + 1), the number of A points in the rotor 100 is one. Become.

  The rotating bodies 100 and 100A can be made of, for example, a neodymium magnet, a ferrite magnet, a samarium cobalt magnet or the like according to the required magnetic flux density.

  In the present embodiment, the first magnetic track 2A and the second magnetic track 2B have an axial type configuration in which one end face in the axial direction of the rotating body 100 is magnetized. With such a configuration, the rotation angle detection device 1 can be thinned in the axial direction, and the hollow hole can be enlarged. Thereby, for example, it becomes easy to apply to the bearing of inner ring rotation type or outer ring rotation type, or to the structure which wires the cable of an apparatus to a hollow hole. The degree of freedom in the design of the device to which the rotation angle detection device 1 is applied can be increased.

  As shown in FIGS. 5 and 6, the magnetic sensor module 200 according to the first embodiment is provided so as to face the rotating body 100 provided with the first magnetic track 2A and the second magnetic track 2B in the axial direction via a gap. It is done. More specifically, the first magnetic sensor 3A of the magnetic sensor module 200 faces the first magnetic track 2A, and detects the magnetic field of the first magnetic track 2A. The second magnetic sensor 3B of the magnetic sensor module 200 faces the second magnetic track 2B and detects the magnetic field of the second magnetic track 2B. The magnetic sensor module 200 is provided at a fixed portion that does not rotate in synchronization with the rotating body 100.

  As shown in FIG. 7, the first magnetic sensor 3A includes two magnetic sensor elements 3A1 and 3A2. The magnetic sensor elements 3A1 and 3A2 are spaced apart in the alignment direction of the magnetic pole pairs 2A1 such that the pitch of one magnetic pole pair 2A1 of the first magnetic track 2A is one period and the phase difference is 90 ° in electrical angle. ing. The second magnetic sensor 3B also includes two magnetic sensor elements 3B1 and 3B2. The magnetic sensor elements 3B1 and 3B2 are spaced apart in the alignment direction of the magnetic pole pairs 2B1 such that the pitch of one magnetic pole pair 2B1 of the second magnetic track 2B is one period and the phase difference is 90 ° in electrical angle. ing.

  As the magnetic sensor elements 3A1 and 3A2 and the magnetic sensor elements 3B1 and 3B2, for example, magnetic sensor elements such as a Hall element or a magnetoresistive effect (MR (Magneto Resistance effect)) sensor can be used.

  The first magnetic sensor 3A outputs a first sin signal sin θ1 which is a sine wave signal according to the phase in the magnetic pole pair 2A1 and a first cos signal cos θ1 which is a cosine wave signal according to the phase in the magnetic pole pair 2A1. Further, the second magnetic sensor 3B outputs a second sin signal sin θ2 which is a sine wave signal according to the phase in the magnetic pole pair 2B1 and a second cos signal cosθ2 which is a cosine wave signal according to the phase in the magnetic pole pair 2B1. Do.

  As shown in FIG. 1, the first sin signal sin θ1 and the first cos signal cos θ1 output from the first magnetic sensor 3A are input to the first phase detection unit 5A. The second sin signal sin θ2 and the second cos signal cos θ2 output from the second magnetic sensor 3B are input to the second phase detection unit 5B.

  FIG. 8 is a diagram showing an example of waveforms of each part of the rotation angle detection device according to the first embodiment, and an example of an ABZ signal and a serial signal generated based on the waveforms of each part. FIG. 8A shows the magnetic pole pattern of the first magnetic track 2A. FIG. 8B shows an example of the magnetic pole pattern of the second magnetic track 2B. (C) of FIG. 8 shows a waveform of the first sin signal sin θ1 input from the magnetic sensor element 3A1 to the first phase detection unit 5A. (D) of FIG. 8 shows a waveform of the first cos signal cos θ1 input from the magnetic sensor element 3A2 to the first phase detection unit 5A. (E) of FIG. 8 shows a waveform of the second sin signal sin θ2 input from the magnetic sensor element 3B1 to the second phase detection unit 5B. (F) of FIG. 8 shows the waveform of the second cos signal cos θ2 input from the magnetic sensor element 3B2 to the second phase detection unit 5B. (G) of FIG. 8 shows the waveform of the detected phase signal output from the first phase detection unit 5A. FIG. 8H shows the waveform of the detection phase signal output from the second phase detection unit 5B. (I) of FIG. 8 shows the waveform of the phase difference signal output from the phase difference detection unit 6.

  (J) of FIG. 8 shows a pulse waveform of an A-phase (θ1) signal obtained by binarizing the first sin signal sin θ1 with H (positive) or L (negative). (K) of FIG. 8 shows a pulse waveform of a B-phase (θ1) signal obtained by binarizing the first cos signal cos θ1 with H (positive) or L (negative). (L) of FIG. 8 shows a pulse waveform of the Z-phase (θ1) signal. The Z-phase (θ1) signal becomes H (positive) when the phase difference indicated by the phase difference signal becomes zero, and becomes L (negative) when the B-phase (θ1) signal falls.

  (M) of FIG. 8 shows a serial signal SA corresponding to the A-phase (θ1) signal, the B-phase (θ1) signal, and the Z-phase (θ1) signal. The serial signal SA has 12 patterns corresponding to the combinations of H and L of the A-phase (θ1) signal, B-phase (θ1) signal and Z-phase (θ1) signal, and the phase difference indicated by the phase difference signal. Serial signals SA0 to SA11. The A-phase (θ1) signal, the B-phase (θ1) signal, and the Z-phase (θ1) signal are generated by the first signal generator 8A. The serial signals SA0 to SA11 are generated by the second signal generator 8B. The serial signals SA0 to SA11 are each composed of 4-bit serial data.

  FIG. 9 is a diagram showing an example of each waveform of the rotation angle detection device according to the first embodiment. (A) to (j) of FIG. 9 show the same waveforms as (a) to (j) of FIG. (J) of FIG. 9 shows a pulse waveform of an A-phase (θ2) signal obtained by binarizing the first sin signal sinθ2 with H (positive) or L (negative). (K) of FIG. 9 shows a pulse waveform of a B-phase (θ2) signal obtained by binarizing the first cos signal cos θ2 with H (positive) or L (negative). (L) of FIG. 9 shows a pulse waveform of the Z-phase (θ2) signal. The Z-phase (θ2) signal becomes H (positive) when the phase difference indicated by the phase difference signal becomes zero, and becomes L (negative) when the B-phase (θ2) signal falls.

  (M) of FIG. 9 shows a serial signal SB corresponding to the A-phase (θ2) signal, the B-phase (θ2) signal, and the Z-phase (θ2) signal. There are eight serial signals SB corresponding to combinations of H and L of A-phase (θ2) signal, B-phase (θ2) signal and Z-phase (θ2) signal, and the magnitude of the phase difference indicated by the phase difference signal. Serial signals SB0 to SB7. The A-phase (θ2) signal, the B-phase (θ2) signal, and the Z-phase (θ2) signal are generated by the first signal generator 8A. The serial signals SB0 to SB7 are generated by the second signal generator 8B. The serial signals SB0 to SB7 are each formed by 4-bit serial data.

  In the example shown in FIGS. 8 and 9, two pole pairs 2B1 of the second magnetic track 2B correspond to a section from point a to point b consisting of three pole pairs 2A1 of the first magnetic track 2A. That is, at points a and b, the phase of the detection signal of the first magnetic sensor 3A matches the phase of the detection signal of the second magnetic sensor 3B. In this case, it is possible to detect an absolute angle at an arbitrary position up to the point b based on the point a. Thus, it is possible to detect an absolute angle between two points at which the phase of the detection signal of the first magnetic sensor 3A and the phase of the detection signal of the second magnetic sensor 3B coincide.

  In the example shown in FIG. 3, the number of pole pairs 2A1 of the first magnetic track 2A is 12, the number of pole pairs 2B1 of the second magnetic track 2B is 8, and the pole phase of the first magnetic track 2A and The magnetic pole phases of the two magnetic tracks 2B coincide with each other. In FIG. 3, the number of A points in the rotating body 100 is four. A pair of A points adjacent in the circumferential direction of the rotating body 100 corresponds to a section from the a point to the b point shown in FIGS. 8 and 9. The magnetic sensor module 200 can detect the absolute angle of the rotating body 100 with the point A at which the phase of the detection signal of the first magnetic sensor 3A and the phase of the detection signal of the second magnetic sensor 3B coincide. . In addition, the magnetic sensor module 200 detects the point A once each time the rotating body 100 rotates by 90 °. The magnetic sensor module 200 can detect the absolute angle of the rotating body 100 even in the range of 90 ° or more by counting the number of detections of the point A.

  Further, in the example shown in FIG. 4, the number of pole pairs 2A1 of the first magnetic track 2A is 32 (P = 32), and the number of pole pairs 2B1 of the second magnetic track 2B is 31 (P-1 = 31). At point A, the magnetic pole phase of the first magnetic track 2A and the magnetic pole phase of the second magnetic track 2B coincide with each other. In the example shown in FIG. 4, the magnetic sensor module 200 sets all points A at which the phase of the detection signal of the first magnetic sensor 3A matches the phase of the detection signal of the second magnetic sensor 3B as an origin position. The absolute angle in the circumference can be detected. Further, the magnetic sensor module 200 detects the point A once each time the rotating body 100 rotates 360 degrees. The magnetic sensor module 200 can detect the absolute angle of the rotating body 100 even in the range of 360 ° or more by counting the number of detections of the point A.

  The first phase detection unit 5A (see FIG. 1) outputs the detection phase signal illustrated in (g) of FIG. 8 based on the input signal illustrated in (c) and (d) of FIG. Specifically, the first phase detection unit 5A calculates the phase (θ1 = arctan (sin θ1 / cos θ1)) in the magnetic pole pair 2A1 from the first sin signal sin θ1 and the first cos signal cos θ1. The second phase detection unit 5B (see FIG. 1) outputs the detection phase signal illustrated in (h) of FIG. 8 based on the input signal illustrated in (e) and (f) of FIG. Specifically, the second phase detection unit 5B calculates the phase (θ2 = arctan (sinθ2 / cosθ2)) in the magnetic pole pair 2B1 from the second sin signal sinθ2 and the second cos signal cosθ2.

  The phase difference detection unit 6 (see FIG. 1) outputs the phase difference signal exemplified in (i) of FIG. 8 based on the detection phase signals output from the first phase detection unit 5A and the second phase detection unit 5B. Do.

  The angle calculation unit 7 (see FIG. 1) converts the phase difference obtained by the phase difference detection unit 6 into an absolute angle in accordance with a preset calculation parameter. The calculation parameters used by the angle calculation unit 7 are stored in the storage unit 10 (see FIG. 1).

  As described above, the signal generator 8 (see FIG. 1) includes the first signal generator 8A (see FIG. 1) and the second signal generator 8B (see FIG. 1). The first signal generation unit 8A, as information on the absolute angle calculated by the angle calculation unit 7 (hereinafter also referred to as “absolute angle information”), includes, for example, an A-phase signal and a B-phase signal different in phase by 90 degrees from each other. An ABZ signal composed of a Z-phase signal indicating an origin position is generated. Then, the first signal generator 8A outputs the generated ABZ signal.

  The first signal generator 8A is for driving the motor through the second output port P2 with the ABZ signal including the A phase (θ1) signal, the B phase (θ1) signal and the Z phase (θ1) signal shown in FIG. While outputting to ECU300 (refer to Drawing 14), it outputs also to host control device 500 (refer to Drawing 14) via the 3rd output port P3. In the present embodiment, the ABZ signal is the first signal.

  The second signal generation unit 8B outputs the serial signals SA0 to SA11 shown in (m) of FIG. 8 to the motor drive ECU 300 via the first output port P1. In the present embodiment, the serial signal is the second signal.

  The storage unit 10 (see FIG. 1) includes the number of magnetic pole pairs 2A1 of the first magnetic track 2A, the number of magnetic pole pairs 2B1 of the second magnetic track 2B, and the absolute angle in addition to the calculation parameters used in the angle calculation unit 7. Information necessary for the operation of the rotation angle detection device 1 such as the reference position is stored. As the storage unit 10, for example, a non-volatile memory is exemplified. The calculation parameters stored in the storage unit 10 and the information necessary for the operation of the rotation angle detection device 1 may be, for example, a configuration that can be updated from the upper control device 500 (see FIG. 14) described later. Thereby, the setting according to the use condition of the rotation angle detection apparatus 1 becomes possible.

  FIG. 10 is a table showing an example of the serial signal and the ABZ signal. As shown in FIG. 10, the serial signals SA0 to SA11 are configured by, for example, 4-bit serial data. The serial data in FIG. 10 is incremented at each rise and fall timing of the A phase (θ1) and the B phase (θ1). Serial data is the rotation angle of the rotating body 100 (see FIGS. 3 and 4) after the first magnetic sensor 3A and the second magnetic sensor 3B detect the point A (see FIGS. 3 and 4) as the origin. It corresponds to As shown in FIG. 10, serial data is reset to zero each time the first magnetic sensor 3A and the second magnetic sensor 3B detect the origin. The ABZ signal in FIG. 10 is composed of a combination of H and L levels of A phase (θ1), H and L levels of B phase (θ1), and H and L levels of Z phase (θ1). Ru. The count value (m) is a value obtained by counting the timing at which the levels of H and L of A phase (θ1) or the levels of H and L of B phase (θ1) are switched. The count value (m) is generated by, for example, a counter 51 (see FIG. 14 described later).

  FIG. 11 is a table showing an example of the serial signal and the ABZ signal. As shown in FIG. 11, the serial signals SB0 to SB7 are also configured by, for example, 4-bit serial data. The serial data in FIG. 11 is incremented at each rise and fall timing of the A phase (θ2) and the B phase (θ2). Serial data is the rotation angle of the rotating body 100 (see FIGS. 3 and 4) after the first magnetic sensor 3A and the second magnetic sensor 3B detect the point A (see FIGS. 3 and 4) as the origin. It corresponds to As shown in FIG. 11, the serial data is reset to zero each time the first magnetic sensor 3A and the second magnetic sensor 3B detect the origin. The ABZ signal in FIG. 11 is composed of a combination of H and L levels of A phase (θ2), H and L levels of B phase (θ2), and H and L levels of Z phase (θ2). Ru. The count value (m) is a value obtained by counting the timing at which the levels of H and L of A phase (θ2) or the levels of H and L of B phase (θ2) are switched. The count value (m) is generated by, for example, a counter 51 (see FIG. 14 described later).

  FIG. 12 is a diagram illustrating an example of a transmission mode of serial signals. As shown in FIG. 12, the second signal generator 8B attaches serial signals SC and SD to the serial signals SA and SB and transmits them. The serial signal SC includes information on the status of the rotation angle detection device 1. For example, the serial signal SC includes the count value n (see FIG. 14) of the point A (see FIGS. 3 and 4) which is the origin. In addition, the serial signal SD includes information for bit check.

  FIG. 13 is a flowchart illustrating an example of a method of detecting an absolute angle by the rotation angle detection device according to the first embodiment. In FIG. 13, the rotation angle detection device 1 (see FIG. 1) has respective phases (see FIGS. 8 and 9) of the first sin signal sinθ1 and the first cos signal cosθ1 and respective phases of the second sin signal sinθ2 and the second cos signal cosθ2 (See FIG. 8 and FIG. 9) respectively. (Step ST1). For example, each phase of the first sin signal sin θ1 and the first cos signal cos θ1 is detected by the first phase detection unit 5A (see FIG. 1) of the rotation angle detection device 1. The respective phases of the second sin signal sinθ2 and the second cos signal cosθ2 are detected by the second phase detection unit 5B (see FIG. 1) of the rotation angle detection device 1.

  Next, the rotation angle detection device 1 detects the phase difference between the first sin signal sin θ1 and the second sin signal sin θ2 (step ST2). Further, the rotation angle detection device 1 detects a phase difference between the first cos signal cosθ1 and the second cos signal cosθ2. For example, detection of these phase differences is performed by the phase difference detection unit 6 (see FIG. 1) of the rotation angle detection device 1.

  Next, the rotation angle detection device 1 calculates the absolute angle of the rotating body 100 based on the detected phase difference (step ST3). For example, calculation of the absolute angle is performed by the angle calculation unit 7 (see FIG. 1) of the rotation angle detection device 1 using calculation parameters stored in the storage unit 10 (see FIG. 1) of the rotation angle detection device 1 .

  Next, the rotation angle detection device 1 converts the calculated absolute angle information into an ABZ signal and outputs it. Further, the rotation angle detection device 1 converts the calculated absolute angle information into a serial signal and outputs it (step ST4). For example, the conversion and output of an absolute angle into an ABZ signal is performed by the first signal generator 8A (see FIG. 1) of the rotation angle detection device 1. The conversion and output of the absolute angle into a serial signal is performed by the second signal generator 8B (see FIG. 1) of the rotation angle detector 1.

  FIG. 14 is a diagram illustrating an example of the motor system according to the first embodiment. As shown in FIG. 14, the motor system 101 according to the first embodiment includes a motor M1 and a motor control device 50 that controls the motor M1. Further, the motor control device 50 includes the rotation angle detection device 1 and a motor drive ECU (Electronic Control Unit) 300.

  The motor M1 is a device that directly transmits the rotational force to the drive target, and is, for example, a direct drive (hereinafter, DD) motor. Since the DD motor directly transmits the rotational force to the driven object, the friction loss can be reduced and the rotation efficiency can be improved. The motor M1 rotates the rotation axis X of the rotating body 100.

  The motor drive ECU 300 is a control device that transmits a signal to the motor M1 for control, and is, for example, a DD drive servo amplifier. The motor drive ECU 300 includes a counter 51, a signal comparison unit 52, a control unit (for example, a motor control unit) 53, and a power amplifier 54.

  The device including the counter 51, the signal comparison unit 52, and the motor control unit 53 is a computer, and for example, a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), and an internal storage unit. , An input interface, and an output interface. The CPU, the ROM, the RAM, and the internal storage unit are connected by an internal bus. Programs such as BIOS are stored in the ROM. The internal storage unit is, for example, a hard disk drive (HDD) or a flash memory, and stores an operating system program and an application program. The CPU realizes various functions by executing a program stored in the ROM or the internal storage unit while using the RAM as a work area.

  The counter 51 is connected to the second output port P2 of the rotation angle detection device 1 via a signal line. The ABZ signal output from the second output port P2 is input to the counter 51. The counter 51 detects and counts the Z-phase (θ1) signal (that is, the origin) of the input ABZ signal. Further, for the input ABZ signal, the counter 51 causes the L-to-H rise of the A-phase (θ1) signal, the H-to-L fall of the A-phase (θ1) signal, and the B-phase (θ1) signal. And the falling of the B phase (θ 1) signal from H to L are detected and counted. For example, it is assumed that the count value for the Z-phase (θ1) signal is n. The count value for the A-phase (θ1) signal and the B-phase (θ1) signal is m. The counter 51 resets the count value m to zero each time the origin is detected. Between the time when the counter 51 detects the origin and the next time the origin is detected, the count value m is counted stepwise according to the rotation angle of the rotating body 100 (see FIG. 1). Therefore, the count values m and n include absolute angle information of the rotating body 100. The counter 51 converts the count values m and n into binary signals and outputs the signals to the signal comparison unit 52.

  The signal comparison unit 52 is connected to the first output port P1 of the rotation angle detection device 1 via a signal line. The signal comparison unit 52 receives the serial signal output from the first output port P1. Further, the count values m and n of the ABZ signal from the counter 51 are input to the signal comparison unit 52. The signal comparison unit 52 compares the serial signal SA input in the same period with the count value m, and determines whether the serial signal SA matches the count value m. For example, as shown in FIG. 10, when the 4-bit serial data included in the serial signal SA matches the count value m generated by the counter 51, the signal comparison unit 52 indicates that the serial signals SA and SC indicate It is determined that the absolute angle and the absolute angle indicated by the ABZ signal are the same.

  On the other hand, when the 4-bit serial data included in the serial signal SA does not match the count value m generated by the counter 51, the signal comparison unit 52 indicates the absolute angle indicated by the serial signals SA and SC and the ABZ signal. It is determined that the absolute angles are not the same. The signal comparison unit 52 outputs information Dat including the comparison result to the motor control unit 53.

  The motor control unit 53 is connected to the first output port P1 of the rotation angle detection device 1 via a signal line. The serial signal output from the first output port P1 is input to the motor control unit 53. If the absolute angles indicated by the serial signals SA and SC match the absolute angles indicated by the ABZ signal in the above comparison, the motor control unit 53 controls the motor M1 in the first mode (for example, the normal mode). The power amplifier 54 supplies power to the motor M1 based on the control signal from the motor control unit 53.

  On the other hand, if the absolute angles indicated by the serial signals SA and SC do not match the absolute angles indicated by the ABZ signal in the above comparison, the signal line connecting the rotation angle detection device 1 and the motor drive ECU 300 is disconnected or shorted. And other abnormalities may have occurred. Therefore, the motor control unit 53 controls the motor M1 in the second mode (for example, the limit mode) different from the first mode. In the limit mode, the motor control unit 53 transmits a control signal instructing the power amplifier 54 to stop the supply of power. The power amplifier 54 receives this control signal and stops the supply of power to the motor M1. Thereby, the motor M1 stops its operation.

  Further, the rotation angle detection device 1 can be connected to other control devices by wire or wireless separately from the motor drive ECU. For example, as shown in FIG. 14, the third output port P3 of the rotation angle detection device 1 can be connected to the host control device 500 via a signal line or the like. When the third output port P3 of the rotation angle detection device 1 is connected to the host control device 500 via a signal line or the like, the ABZ signal generated by the rotation angle detection device 1 is output from the third output port P3. It is input to the host controller 500.

  The host control device 500 can monitor the detection state of the absolute angle by the rotation angle detection device 1 and the rotation state of the motor M1 based on the input ABZ signal. Further, the host control device 500 can transmit a control signal to the rotation angle detection device 1 or the motor M1 based on the input ABZ signal. As described above, the rotation angle detection device 1 can be connected not only to the motor drive ECU 300 but also to the host control device 500. Thereby, the number of attached rotation angle detection devices 1 can be reduced compared to the case where a dedicated rotation angle detection device for connection to the host control device 500 is attached to the motor M1.

  FIG. 15 is a flowchart illustrating an example of a motor control method by the motor system according to the first embodiment. In FIG. 15, the motor drive ECU 300 (see FIG. 14) receives the ABZ signal (step ST11), and generates count values m and n (see FIG. 14) (step ST12). Further, the motor drive ECU 300 receives the serial signal in parallel with the reception of the ABZ signal and the generation of the count values m and n (step ST13). The reception of the ABZ signal and the generation of the count values m and n are performed by the counter 51 (see FIG. 14). The signal comparison unit 52 (see FIG. 14) performs reception of the serial signal.

  The motor drive ECU 300 compares the ABZ signal with the serial signal (step ST14). For example, the motor drive ECU 300 compares the count value m of the ABZ signal shown in FIG. 10 with the serial data of the serial signal SA. The signal comparison unit 52 performs the comparison and the output of the information including the comparison result. If the count value m of the ABZ signal matches the serial signal SA (step ST15; Yes), the motor driving ECU 300 controls the motor M1 in the normal mode (step ST16). On the other hand, when the count value m of the ABZ signal and the serial signal SA do not match (step ST15; No), the motor driving ECU 300 controls the motor M1 in the limit mode (step ST17). The motor control unit 53 (see FIG. 14) performs control of the motor M1 in the normal mode or the limit mode via the power amplifier 54 (see FIG. 14).

  As described above, the motor system 101 according to the first embodiment includes the motor M1 and the motor control device 50 that controls the motor 1. The motor control device 50 includes a rotation angle detection device 1 that detects a rotation angle of the motor M1, and a motor drive ECU 300. The rotation angle detection device 1 includes a rotating body 100, a first magnetic sensor 3A and a second magnetic sensor 3B for detecting a rotation angle of the rotating body 100, and a rotation detected by the first magnetic sensor 3A and the second magnetic sensor 3B. The first signal generator 8A converts information on the angle into an ABZ signal and outputs the information, and converts information on the rotation angle detected by the first magnetic sensor 3A and the second magnetic sensor 3B to a serial signal and outputs the second signal And a signal generation unit 8B. The motor drive ECU 300 includes a signal comparison unit 52 that compares the ABZ signal output from the first signal generation unit 8A with the serial signal output from the second signal generation unit 8B.

  According to this, the motor system 101 can determine the presence or absence of abnormality in the ABZ signal which is the first signal and the serial signal which is the second signal based on the comparison result by the signal comparison unit 52. Thereby, the reliability of motor control can be improved. For example, based on the comparison result described above, the motor system 101 outputs a second output port P2 that outputs an ABZ signal, a signal line connected to the second output port P2, a first output port P1 that outputs a serial signal, and It can be determined whether there is a failure or abnormality in the signal line or the like connected to the output port P1. As a failure or abnormality, a power fault, a ground fault, a disconnection, etc. are exemplified.

  The motor system 101 also includes a motor control unit 53 that controls the rotational operation of the motor M1 based on the comparison result by the signal comparison unit 52. When the signal comparison unit 52 determines that the absolute angle indicated by the ABZ signal matches the absolute angle indicated by the serial signal, the motor control unit 53 controls the motor M1 in the normal mode. If the signal comparison unit 52 determines that the absolute angle indicated by the ABZ signal does not match the absolute angle indicated by the serial signal, the motor control unit 53 controls the motor M1 in the limit mode. As a result, when it is determined that there is an abnormality in the ABZ signal or the serial signal, the motor system 101 can stop the motor M1, so that the reliability of motor control can be further improved.

  In addition, the rotation angle detection device 1 includes a first output port P1 that outputs an ABZ signal, and a second output port P2 that outputs a serial signal. Thus, the rotation angle detection device 1 can output the ABZ signal and the serial signal in synchronization. Synchronously outputting means outputting an ABZ signal indicating the same rotation angle and a serial signal within the same period.

(Modification)
In the first embodiment, it has been described that the motor control unit 53 stops the operation of the motor M <b> 1 when the limit mode is set. However, the limit mode is not limited to this. For example, in the signal comparison unit 52, when the count value m of the ABZ signal and the serial signal SA are not synchronized and there is an input of the count value m, the signal comparison unit 52 does not receive the input of the serial signal SA. It may be determined that an abnormality such as disconnection has occurred in the signal line for transmitting the serial signal SA. In this case, the signal comparison unit 52 outputs the count values m and n of the ABZ signal to the motor control unit 53 instead of the serial signal. When count values m and n of the ABZ signal are input to the motor control unit 53, the motor control unit 53 starts motor control based on the count values m and n of the ABZ signal as the limitation mode. According to this, even if the signal output of the serial signal is stopped due to a short circuit, a ground fault, or the like, the motor control unit 53 can acquire absolute angle information from the ABZ signal, and control of the motor M1 It can be done continuously.

  In the first embodiment, the rotation angle detection device 1 outputs the first output port P1 that outputs the count signal to the signal comparison unit 52 and the second output port P2 that outputs the ABZ signal to the signal comparison unit. It explained that it had. However, the rotation angle detection device 1 may include a plurality of first output ports P1 and may include a plurality of second output ports P2. For example, the signal comparison unit 52 transmits a plurality of serial signals having the same absolute angle information via a plurality of first output ports P1 and a plurality of signal lines respectively connected to the plurality of first output ports P1. You may enter each in. In addition, a plurality of ABZ signals having the same absolute angle information are transmitted to the counter 51 via the plurality of second output ports P2 and the plurality of signal lines respectively connected to the plurality of second output ports P2. You may enter it. In this case, the counter 51 generates count values m and n for each of the plurality of ABZ signals and outputs the count values m and n to the signal comparison unit 52. The input path of the serial signal or count value m, n to the signal comparison unit 52 is three or more.

  As described above, when there are three or more input paths of serial signals or count values m and n, the signal comparison unit 52 determines whether the absolute angle indicated by the serial signal matches the absolute angle indicated by the count values m and n. It may be decided by majority decision whether it is not. For example, when the serial signal whose absolute angle matches or the count value m, n exceeds half of the whole, the signal comparison unit 52 determines that the absolute angle indicated by the serial signal matches the absolute angle indicated by the count value m, n. to decide. On the other hand, when the serial signal whose absolute angle matches or the count values m and n are less than half of the whole, the signal comparison unit 52 does not match the absolute angle indicated by the serial signal and the absolute angle indicated by the count values m and n. I will judge. According to this, even when one input path among the three or more input paths is disconnected, the signal comparison unit 52 can continuously make the above determination.

  In the first embodiment, the first signal generation unit 8A is configured to generate the second ABZ signal including the A-phase (θ1) signal, the B-phase (θ1) signal, and the Z-phase (θ1) signal shown in FIG. It has been described that each output to the outside through the output port P2 and the third output port P3. However, in the present embodiment, the first signal generation unit 8A does not configure the ABZ signal by the A-phase (θ1) signal, the B-phase (θ1) signal, and the Z-phase (θ1) signal shown in FIG. It may be configured by the A-phase (θ2) signal, the B-phase (θ2) signal, and the Z-phase (θ2) signal shown in FIG. Then, the first signal generation unit 8A generates an ABZ signal (θ2) including the A-phase (θ2) signal, the B-phase (θ2) signal, and the Z-phase (θ2) signal as the second output port P2 and the third output. It may be output to the outside through the port P3.

  In that case, the signal comparison unit 52 compares the serial signal SB input in the same period with the count value m of the ABZ signal (θ2) to obtain the absolute angle indicated by the serial signals SB and SC, and the count value m. It is determined whether the absolute angle indicated by n, n matches. For example, when the 4-bit serial data (see FIG. 11) included in the serial signal SB matches the count value m of the ABZ signal (θ2), the signal comparison unit 52 determines the absolute angle indicated by the serial signals SB and SC. And the absolute angle indicated by the ABZ signal is the same.

Second Embodiment
FIG. 16 is a diagram illustrating an example of a motor system according to the second embodiment. As shown in FIG. 16, a motor system 101A according to the second embodiment includes a motor M1 and a motor control device 50A. Further, motor control device 50A includes rotation angle detection device 1 and ECU 400 for system control. The system control ECU 400 further includes a counter 51, a signal comparison unit 52, a system control unit 55, and a motor drive ECU 300A. The motor drive ECU 300A includes a motor control unit 53 and a power amplifier 54.

  The device including the counter 51, the signal comparison unit 52, and the system control unit 55 is a computer, and includes, for example, a CPU, a ROM, a RAM, an internal storage unit, an input interface, and an output interface. The CPU, the ROM, the RAM, and the internal storage unit are connected by an internal bus. Programs such as BIOS are stored in the ROM. The motor control unit 53 may be included in the same computer as the system control unit 55, or may be included in a computer other than the system control unit 55.

  The system control ECU 400 has a function of driving the motor M1. Further, the system control ECU 400 executes steps ST11 to ST17 of the flowchart shown in FIG. For example, the system control ECU 400 receives the ABZ signal (step ST11), and outputs count values m and n (see FIG. 14) (step ST12). Further, the system control ECU 400 receives the serial signal in parallel with the reception and counting of the ABZ signal (step ST13). The counter 51 performs reception of the ABZ signal and generation of the count values m and n. The signal comparison unit 52 performs reception of the serial signal.

  Next, the system control ECU 400 compares the ABZ signal with the serial signal (step ST14). For example, the system control ECU 400 compares the count value m of the ABZ signal shown in FIG. 10 with the serial data of the serial signal SA. The signal comparison unit 52 performs the comparison and the output of the information Dat including the comparison result. If the absolute angle indicated by the ABZ signal matches the absolute angle indicated by the serial signal (step ST15; Yes), the system control ECU 400 controls the motor M1 in the normal mode (step ST16). On the other hand, when the absolute angle indicated by the ABZ signal does not match the absolute angle indicated by the serial signal (step ST15; No), the system control ECU 400 controls the motor M1 in the limit mode (step ST17). The control in the normal mode or the limit mode of the motor M1 is performed by the motor control unit 53 via the power amplifier 54 under the control of the system control unit 55.

  Similar to the motor system 101 according to the first embodiment, the motor system 101A according to the second embodiment can improve the reliability of motor control. Also in the motor system 101A according to the second embodiment, the modification described in the first embodiment is applicable.

(Embodiment 3)
FIG. 17 is a diagram illustrating an example of a motor system according to the third embodiment. As shown in FIG. 17, a motor system 101B according to the third embodiment includes a motor (hereinafter, referred to as a first motor) M1, a second motor M2, and a motor control device 50B. Further, the motor control device 50B includes a first rotation angle detection device 1A that detects the rotation angle of the first motor M1, a second rotation angle detection device 1B that detects the rotation angle of the second motor M2, and a system control ECU 400A. And.

  The first motor M1 and the second motor M2 have the same configuration as the motor M1, and are, for example, DD motors. Further, the first rotation angle detection device 1A and the second rotation angle detection device 1B have the same configuration as the rotation angle detection device 1 shown in FIG. The first rotation angle detection device 1A outputs an output port P1A that outputs a serial signal to the system control ECU 400A, an output port P2A that outputs an ABZ signal to the system control ECU 400A, and an output that outputs an ABZ signal to the host control device 500. And a port P3A. The second rotation angle detection device 1B outputs an output port P1B that outputs a serial signal to the system control ECU 400A, an output port P2B that outputs an ABZ signal to the system control ECU 400A, and an output that outputs an ABZ signal to the host control device 500. And a port P3B.

  The system control ECU 400A includes a first counter 51A, a first signal comparison unit 52A, a motor drive ECU (hereinafter, referred to as a first motor drive ECU) 300A, a second counter 51B, and a second signal comparison unit 52B. , The second motor drive ECU 300B, and the system control unit 55. The second motor drive ECU 300B has the same configuration as the first motor drive ECU 300A.

  The apparatus including the first counter 51A, the second counter 51B, the first signal comparison unit 52A, the second signal comparison unit 52B, and the system control unit 55 is a computer as in the second embodiment. The motor control unit 53 of the first motor drive ECU 300A and the motor control unit 53 of the second motor drive ECU 300B may be included in the same computer as the system control unit 55 or separately from the system control unit 55. May be included in the computer.

  The system control ECU 400A has a function of driving the first motor M1 and the second motor M2. Further, the system control ECU 400A executes steps ST11 to ST17 of the flowchart shown in FIG. 15 for each of the first motor M1 and the second motor M2.

  For example, the first counter 51A receives the ABZ signal output from the output port P2A (step ST11), and generates count values m and n (step ST12). The first signal comparison unit 52A receives the serial signal output from the output port P1A in parallel with the reception of the ABZ signal output from the output port P2A and the generation of the count values m and n (step ST13). . The first signal comparison unit 52A compares the ABZ signal output from the output port P1A with the serial signal output from the output port P1A (step ST14), and outputs information DatA including the comparison result. For example, the system control ECU 400A compares the count value m of the ABZ signal shown in FIG. 10 with the serial data of the serial signal SA, and outputs information DatA including the comparison result. If the absolute angle indicated by the ABZ signal matches the absolute angle indicated by the serial signal (step ST15; Yes), the system control unit 55 controls the first motor M1 in the normal mode via the first motor drive ECU 300A. To do (step ST16). On the other hand, when the absolute angle indicated by the ABZ signal does not match the absolute angle indicated by the serial signal (step ST15; No), the system control unit 55 restricts the first motor M1 via the first motor drive ECU 300A. The mode is controlled (step ST17).

  Similarly, the second counter 51B receives the ABZ signal output from the output port P2B (step ST11), and generates count values m and n (step ST12). In addition, the second signal comparison unit 52B receives the serial signal output from the output port P1B in parallel with the reception of the ABZ signal output from the output port P2B and the generation of the count values m and n (step ST13). . The second signal comparison unit 52B compares the ABZ signal output from the output port P1B with the serial signal output from the output port P1B (step ST14), and outputs information DatB including the comparison result. For example, the system control ECU 400B compares the count value m of the ABZ signal with the serial data of the serial signal SA, and outputs information DatB including the comparison result. If the absolute angle indicated by the ABZ signal matches the absolute angle indicated by the serial signal (step ST15; Yes), the system control unit 55 controls the second motor M2 in the normal mode via the second motor drive ECU 300B. To do (step ST16). On the other hand, when the absolute angle indicated by the ABZ signal does not match the absolute angle indicated by the serial signal (step ST15; No), the system control unit 55 restricts the second motor M2 via the second motor drive ECU 300B. The mode is controlled (step ST17).

  Similar to the motor system 101 according to the first embodiment and the motor system 101A according to the second embodiment, the motor system 101B according to the third embodiment can improve the reliability of motor control. Further, in the motor system 101B according to the third embodiment, for example, when the first signal comparison unit 52A determines that there is an abnormality in the ABZ signal or the serial signal, the system control unit 55 determines not only the first motor drive ECU 300A. Control in the limit mode can also be instructed to the second motor drive ECU 300B. Thereby, the reliability of motor control can be further improved. Also in the motor system 101B according to the third embodiment, the modification described in the first embodiment is applicable.

  The motor control device and motor system of the present embodiment may be changed as appropriate. For example, the first signal and the second signal may each be the same type of signal. The first and second signals may both be ABZ signals. Also, both the first signal and the second signal may be serial signals. Even with such a configuration, the signal comparison unit compares the first signal and the second signal to confirm the likelihood of the first signal and the second signal, thus improving the reliability of motor control. It can be done.

1 rotation angle detection device 1A first rotation angle detection device 1B second rotation angle detection device 2 magnetic track 2A first magnetic track 2A1 magnetic pole pair 2B second magnetic track 2B1 magnetic pole pair 3A first magnetic sensor 3B second magnetic sensor 5A 1 phase detection unit 5B second phase detection unit 6 phase difference detection unit 7 angle calculation unit 8 signal generation unit 8A first signal generation unit 8B second signal generation unit 10 storage units 50, 50A, 50B motor control device 51 counter 51A 1 counter 51B second counter 52 signal comparison unit 52A first signal comparison unit 52B second signal comparison unit 53 motor control unit 54 power amplifier 55 system control unit 100, 100A rotating body 101, 101A, 101B motor system 200 magnetic sensor module 300 Motor drive ECU
300A 1st motor drive ECU
300B Second motor drive ECU
400, 400A System control ECU
500 Host Controller M1 Motor (1st motor)
M2 second motor

Claims (8)

A rotating body attached to the motor,
A sensor unit that detects a rotation angle of the rotating body;
A first signal generation unit configured to convert information on the rotation angle detected by the sensor unit into a first signal and output the first signal;
A rotation angle detection device having a second signal generation unit configured to convert information on the rotation angle detected by the sensor unit into a second signal and output the second signal;
A signal comparison unit that compares the first signal output from the first signal generation unit with the second signal output from the second signal generation unit.   The motor control device according to claim 1, wherein the first signal and the second signal have different signal types. The first signal is an ABZ signal,
The second signal is a serial signal,
A counter that detects a pulse waveform in the ABZ signal and generates a count value of the ABZ signal;
The motor control device according to claim 1, wherein the signal comparison unit compares the count value with the serial signal. The rotation angle detection device
A first output port for outputting the first signal;
The motor control device according to any one of claims 1 to 3, further comprising: a second output port that outputs the second signal. The rotating body has a plurality of magnetic tracks in which magnetic pole pairs consisting of an N pole and an S pole are arranged concentrically at regular intervals in a ring shape and the number of magnetic pole pairs is different from each other.
The sensor comprises a plurality of magnetic sensors that sense the magnetic field of one of the magnetic tracks and output sin and cos signals.
The rotation angle detection device
A phase detection unit that calculates the phases of the sin signal and the cos signal;
A phase difference detection unit that calculates a phase difference between a plurality of the phases;
An angle calculating unit that calculates an absolute angle of the rotating body based on the phase difference;
The first signal generator converts the information on the absolute angle calculated by the angle calculator into the first signal and outputs the first signal.
The motor control device according to any one of claims 1 to 4, wherein the second signal generation unit converts information on the absolute angle calculated by the angle calculation unit into the second signal and outputs the second signal.   The motor control device according to any one of claims 1 to 5, further comprising: a control unit configured to control a rotational operation of the motor based on a comparison result by the signal comparison unit. When it is determined by the comparison result that the rotation angle indicated by the first signal and the rotation angle indicated by the second signal match, the control unit controls the motor in a first mode,
When it is determined by the comparison result that the rotation angle indicated by the first signal and the rotation angle indicated by the second signal do not match, the control unit is in a second mode different from the first mode. The motor control device according to claim 6, which controls the motor. Motor,
A motor control device for controlling the motor;
The motor control device
A rotating body attached to the motor;
A sensor unit that detects a rotation angle of the rotating body;
A first signal generation unit configured to convert information on the rotation angle detected by the sensor unit into a first signal and output the first signal;
A rotation angle detection device having a second signal generation unit configured to convert information on the rotation angle detected by the sensor unit into a second signal and output the second signal;
A motor system comprising: a signal comparison unit that compares the first signal output from the first signal generation unit with the second signal output from the second signal generation unit.

Images