WO2021186820A1 - State detection device and motor unit - Google Patents

Abstract

A state detection device according to one aspect of the present invention comprises: at least three detection units that have a first magnetic sensor facing a permanent magnet in an axial direction of a rotor of a motor and a second magnetic sensor facing a stator of the motor in the axial direction, and are provided in the rotation direction of the rotor; a calculation unit that calculates, for each detection unit, a rotor magnetic flux component and a stator magnetic flux component, on the basis of a first detection signal indicating a magnetic flux detection result obtained by the first magnetic sensor and a second detection signal indicating a magnetic flux detection result obtained by the second magnetic sensor; and an estimation unit that estimates, as the state quantities of the motor, a rotation position of the rotor, a coil current flowing through a coil, and a torque of the motor, on the basis of the rotor magnetic flux component and the stator magnetic flux component obtained from the calculation unit. In each of the detection units, the first magnetic sensor and the second magnetic sensor are arranged in a radial direction of the rotor.

Description

State detector and motor unit

The present invention relates to a state detection device and a motor unit.

A general motor unit includes a motor, a position detection device that detects the rotation position of the motor, and a control device that controls the motor based on the detection result of the rotation position obtained from the position detection device. The following Patent Document 1 includes a sensor magnet, which is a disk-shaped magnet attached to the rotating shaft of a motor, and a magnetic sensor provided at a position facing the sensor magnet in the axial direction of the rotating shaft. The position detection device of the above is disclosed.

To control the motor, not only the information on the rotation position but also the information on the coil current flowing through the coil of the motor and the information on the torque of the motor are required. Therefore, the control device has a function of detecting the coil current by a current sensor such as a shunt resistor and a function of estimating the torque based on the detection value of the coil current and the voltage command value (see Patent Documents 2 to 4). ).

Japanese Unexamined Patent Publication No. 2016-133376 Japanese Unexamined Patent Publication No. 2015-12770 Japanese Unexamined Patent Publication No. 2009-33876 Japanese Patent No. 6135713

In recent years, there has been a demand for the development of an all-in-one type compact sensor having a function of detecting all the state quantities (rotational position, coil current and torque) of the motor, which is information necessary for motor control. However, as described in Patent Documents 2 to 4, a current sensor built in the control device is required for torque estimation, and as described in Patent Document 1, the detection of the rotation position. In some cases, a dedicated sensor magnet is required, which leads to an increase in the size of the sensor.

Therefore, in order to obtain an all-in-one type compact sensor as a sensor independent of the control device, it is possible to detect the coil current and estimate the torque without a current sensor, and to detect the rotation position without a dedicated sensor magnet. Technology is needed.

In view of the above circumstances, one object of the present invention is to provide a state detection device that can be used as an all-in-one type small sensor independent of the control device, and a motor unit including the state detection device.

One aspect of the state detection device of the present invention is a state detection device that detects the state amount of a motor including a stator having a coil and a rotor having a permanent magnet. The state detection device of this embodiment has a first magnetic sensor facing the permanent magnet in the axial direction of the rotor and a second magnetic sensor facing the stator in the axial direction of the rotor. At least three detection units provided along the rotation direction, a first detection signal indicating a magnetic flux detection result obtained from the first magnetic sensor, and a second detection signal indicating a magnetic flux detection result obtained from the second magnetic sensor. Based on the above, a calculation unit that calculates the rotor magnetic flux component and the stator magnetic flux component for each detection unit, and the rotor magnetic flux component and the stator magnetic flux component obtained from the calculation unit, the rotor. A rotation position of the above, a coil current flowing through the coil, and an estimation unit that estimates the torque of the motor as the state quantity. In each of the detection units, the first magnetic sensor and the second magnetic sensor are arranged along the radial direction of the rotor.

One aspect of the motor unit of the present invention is a motor including a stator having a coil and a rotor having a permanent magnet, a state detection device of the above aspect for detecting the state amount of the motor, and the state detection. A control device for controlling the motor based on the detection result of the state quantity obtained from the device is provided.

According to the above aspect of the present invention, it is possible to provide a state detection device that can be used as an all-in-one type small sensor independent of the control device, and a motor unit including the state detection device.

FIG. 1 is a block diagram showing a configuration of a motor unit according to the present embodiment. FIG. 2 is a diagram showing the arrangement of the first magnetic sensor and the second magnetic sensor with respect to the motor in the present embodiment. FIG. 3 is a diagram showing the positional relationship between the first magnetic sensor and the second magnetic sensor in the present embodiment. FIG. 4 is a diagram showing a detailed configuration of a calculation unit included in the state detection device according to the present embodiment. FIG. 5 is a diagram showing a modified example of the calculation unit included in the state detection device according to the present embodiment.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a block diagram showing the configuration of the motor unit 1 of the present embodiment. As shown in FIG. 1, the motor unit 1 of the present embodiment includes a motor 10, a state detection device 20, and a control device 30. The motor unit 1 is used as a device that generates a rotational force in various fields such as automobiles, robots, home appliances, industrial equipment, and medical equipment.

As shown in FIG. 2, the motor 10 in this embodiment is, for example, an inner rotor type three-phase brushless DC motor. The motor 10 includes a rotor (rotor) 100 and a stator (stator) 200. Although not shown, the motor 10 also includes a motor housing that houses the rotor 100 and the stator 200, and bearing parts such as ball bearings. The figure on the left side of FIG. 2 is a view of the motor 10 viewed from one end side of the central axis CA of the rotor 100. The figure on the right side of FIG. 2 is a view of the cross section of the motor 10 along the IV-IV line as viewed from the direction of the arrow in the drawing.

The rotor 100 is a rotating body that is rotatably supported by bearing parts around the central axis CA inside the motor housing. In the present embodiment, the direction parallel to the central axis CA of the rotor 100 is defined as the axial direction, and the direction orthogonal to the central axis CA is defined as the radial direction. Further, in the radial direction, the direction away from the central axis CA is defined as the radial outer side, and the direction closer to the central axis CA is defined as the radial inner side. The rotor 100 includes a rotor core 110, a rotor shaft 120, and 10 rotor magnets 130.

The rotor core 110 is an annular iron core component having a predetermined axial length. The rotor core 110 is formed by laminating a plurality of thin electromagnetic steel sheets having the same shape in the axial direction. The rotor shaft 120 is a columnar shaft component having an axial length longer than that of the rotor core 110. The rotor shaft 120 is coaxially joined to the rotor core 110 in a state of axially penetrating the inside of the rotor core 110 in the radial direction. The central axis of the rotor core 110 and the rotor shaft 120 is the central axis CA of the rotor 100. Among the components of the rotor 100, the rotor shaft 120 is rotatably supported by the bearing component about the central axis CA.

The rotor magnet 130 is a plate-shaped permanent magnet having substantially the same axial length as the rotor core 110. The rotor magnet 130 has an arcuate cross section when viewed from the axial direction. On the outer peripheral surface of the rotor core 110, ten grooves (magnet slots) that are recessed inward in the radial direction and extend in the axial direction are provided at intervals of 36 ° along the rotation direction of the rotor 100. By inserting one rotor magnet 130 into one magnet slot, a total of ten rotor magnets 130 are arranged at intervals of 36 ° along the rotation direction on the outer peripheral surface of the rotor core 110. In this embodiment, the case where the rotor 100 has 10 rotor magnets 130 is illustrated, but the number of rotor magnets 130 is not limited to 10. The number of rotor magnets 130 is appropriately determined according to the performance required for the motor 10. Further, in the present embodiment, the case where the motor 10 has an IPM type (embedded magnet type) rotor 100 is illustrated, but the motor 10 may have an SPM type (surface magnet type) rotor.

The stator 200 is fixed inside the motor housing while surrounding the outer peripheral surface of the rotor 100, and generates an electromagnetic force for rotating the rotor 100. The stator 200 has a stator core 210 and a coil 220. Although not shown, the stator 200 has an insulator for electrically insulating the stator core 210 and the coil 220.

The stator core 210 is an iron core component having a yoke 211 and 12 teeth 212. The yoke 211 is an annular portion having substantially the same axial length as the rotor core 110. The central axis of the yoke 211 coincides with the central axis CA of the rotor 100. The tooth 212 is a portion that protrudes inward in the radial direction from the inner peripheral surface of the yoke 211. On the inner peripheral surface of the yoke 211, twelve teeth 212 are provided at intervals of 30 ° along the rotation direction. That is, the stator 200 in the present embodiment has 12 slots provided at intervals of 30 ° along the rotation direction. An arcuate tip surface is provided on the inner tip of each tooth 212 in the radial direction when viewed from the axial direction. The tip surface of each tooth 212 faces each rotor magnet 130 in the radial direction. The above-mentioned stator core 210 is formed by laminating a plurality of thin electromagnetic steel sheets having the same shape in the axial direction.

The coil 220 is a coil to which a three-phase drive current is supplied from the control device 30. The coil 220 includes a U-phase coil 221, a V-phase coil 222, and a W-phase coil 223. The U-phase coil 221 is a coil to which the U-phase drive current Iu is supplied from the control device 30. The V-phase coil 222 is a coil to which the V-phase drive current Iv is supplied from the control device 30. The W-phase coil 223 is a coil to which the W-phase drive current Iw is supplied from the control device 30. In the following, when it is not necessary to distinguish between the U-phase drive current Iu, the V-phase drive current Iv, and the W-phase drive current Iw, these currents are collectively referred to as coil currents I.

The U-phase coil 221 is wound around four teeth 212 separated by 90 ° in the rotation direction by a distributed winding method among the twelve teeth 212. Of the 12 teeth 212, the V-phase coil 222 is wound by a distributed winding method on four teeth 212 adjacent to the wound teeth 212 on which the U-phase coil 221 is wound and separated by 90 ° in the rotation direction. .. Of the 12 teeth 212, the W-phase coil 223 is wound around the four teeth 212 on which the V-phase coil 222 is wound and separated by 90 ° in the rotation direction by a distributed winding method. ..

As shown in FIG. 1, the state detection device 20 detects the state amount of the motor 10 and outputs a signal indicating the detection result of the state amount to the control device 30. The state quantity of the motor 10 includes the rotation position of the motor 10, that is, the rotation angle θ _{R of the} rotor 100, the coil currents I (Iu, Iv and Iw) flowing through the coil 220, and the torque T of the motor 10. That is, the state detection device 20 detects the rotation angle θ _R , the coil currents I (Iu, Iv and Iw), and the torque T as the state quantities of the motor 10, and controls a signal indicating the detection results of those state quantities. Output to device 30.

The state detection device 20 includes a U-phase detection unit 21u, a V-phase detection unit 21v, a W-phase detection unit 21w, a calculation unit 22, and a state estimation unit 23. In the following, when it is not necessary to distinguish between the U-phase detection unit 21u, the V-phase detection unit 21v, and the W-phase detection unit 21w, these three components are collectively referred to as the detection unit 21. That is, the state detection device 20 in the present embodiment includes at least three detection units 21.

The U-phase detection unit 21u has a U-phase first magnetic sensor HAu and a U-phase second magnetic sensor HBu. The V-phase detection unit 21v includes a V-phase first magnetic sensor HAv and a V-phase second magnetic sensor HBv. The W-phase detection unit 21w has a W-phase first magnetic sensor HAw and a W-phase second magnetic sensor HBw. In the following, when it is not necessary to distinguish between the U-phase first magnetic sensor HAu, the V-phase first magnetic sensor HAv, and the W-phase first magnetic sensor HAw, these three magnetic sensors are collectively referred to as the first magnetic sensor HA. do. Similarly, when it is not necessary to distinguish between the U-phase second magnetic sensor HBu, the V-phase second magnetic sensor HBv, and the W-phase second magnetic sensor HBw, these three magnetic sensors are collectively referred to as the second magnetic sensor HB. do. That is, in the present embodiment, each of the three detection units 21 has a first magnetic sensor HA and a second magnetic sensor HB, respectively. Twice

As shown in the figure on the right side of FIG. 2, the state detection device 20 includes a disk-shaped circuit board 24. The circuit board 24 has a shaft insertion hole 24a which is a hole penetrating in the plate thickness direction. The circuit board 24 is fixed in the motor housing in a state where the thickness direction of the circuit board 24 coincides with the axial direction of the rotor 100 and the rotor shaft 120 is inserted into the shaft insertion hole 24a. The three detection units 21 are provided on the plate surface 24b of the circuit board 24 facing the motor 10 side. That is, the first magnetic sensor HA and the second magnetic sensor HB of each of the three detection units 21 are mounted on the plate surface 24b of the circuit board 24. The circuit board 24 may be a circuit board that the rotor shaft 120 does not penetrate. In this case, it is not necessary to provide the shaft insertion hole 24a in the circuit board 24.

As shown in the figure on the right side of FIG. 2, in each of the three detection units 21, the first magnetic sensor HA faces the rotor magnet 130 in the axial direction, and the second magnetic sensor HB faces the stator 200 in the axial direction. opposite. In the present embodiment, the first magnetic sensor HA and the second magnetic sensor HB are chip-type Hall sensors. Generally, a chip-type Hall sensor has a marked flat surface as a detection surface. The chip-type Hall sensor outputs an analog voltage signal proportional to the magnetic flux density of the magnetic flux interlinking with the detection surface. The first magnetic sensor HA is mounted on the plate surface 24b of the circuit board 24 with its detection surface facing the rotor magnet 130 in the axial direction. Further, the second magnetic sensor HB is mounted on the plate surface 24b of the circuit board 24 with its detection surface facing the stator 200 in the axial direction.

Note that FIG. 2 illustrates a case where all the detection surfaces of the first magnetic sensor HA face the rotor magnet 130 and all the detection surfaces of the second magnetic sensor HB face the stator 200. However, since FIG. 2 is only a schematic diagram, the actual chip sizes of the first magnetic sensor HA and the second magnetic sensor HB may differ from the sizes shown in FIG. In that case, at least a part of the detection surface of the first magnetic sensor HA may face the rotor magnet 130 in the axial direction. Further, at least a part of the detection surface of the second magnetic sensor HB may face the stator 200 in the axial direction.

As shown in the figure on the left side of FIG. 2, in the present embodiment, the three detection units 21 are provided at intervals of 60 ° along the rotation direction of the rotor 100 when viewed from the axial direction. That is, the three first magnetic sensors HA are provided at intervals of 60 ° along the rotation direction of the rotor 100 when viewed from the axial direction. Further, the three second magnetic sensors HB are provided at intervals of 60 ° along the rotation direction of the rotor 100 when viewed from the axial direction. The three detection units 21 may be provided at intervals of 120 ° along the rotation direction of the rotor 100.

As shown in the figure on the left side of FIG. 2, in each of the three detection units 21, the first magnetic sensor HA and the second magnetic sensor HB are arranged along the radial direction of the rotor 100 when viewed from the axial direction. For example, as shown in FIG. 3, when one detection unit 21 is viewed from the axial direction, a straight line passing through the center P2 of the second magnetic sensor HB and the center axis CA of the rotor 100 is defined as the reference line L. The center P1 of the first magnetic sensor HA is located within a range extending ± 2 mm with respect to the reference line L in the direction orthogonal to the reference line L. As described above, in each of the three detection units 21, both the center P1 of the first magnetic sensor HA and the center P2 of the second magnetic sensor HB do not necessarily have to be located on the same straight line extending in the radial direction. That is, in the present embodiment, "the first magnetic sensor HA and the second magnetic sensor HB are arranged along the radial direction of the rotor 100" means that the first magnetic sensor HA and the second magnetic sensor HB are relative to each other. Includes the meaning of allowing misalignment.

As shown in FIG. 1, the U-phase first magnetic sensor HAu of the U-phase detection unit 21u transmits an analog voltage signal proportional to the magnetic flux density of the magnetic flux interlinking with the detection surface, and U-phase showing the magnetic flux detection result. It is output to the calculation unit 22 as the first detection signal _VHAu. The U-phase second magnetic sensor HBu of the U-phase detection unit 21u uses an analog voltage signal proportional to the magnetic flux density of the magnetic flux interlinking with the detection surface as a U-phase second detection signal V _{HBu indicating the magnetic flux detection result.} Output to the calculation unit 22.

The V-phase first magnetic sensor HAv of the V-phase detection unit 21v uses an analog voltage signal proportional to the magnetic flux density of the magnetic flux interlinking with the detection surface as a V-phase first detection signal V _{HAv indicating the magnetic flux detection result.} Output to the calculation unit 22. The V-phase second magnetic sensor HBv of the V-phase detection unit 21v uses an analog voltage signal proportional to the magnetic flux density of the magnetic flux interlinking with the detection surface as a V-phase second detection signal V _{HBv indicating the magnetic flux detection result.} Output to the calculation unit 22.

The W-phase first magnetic sensor HAw of the W-phase detection unit 21w uses an analog voltage signal proportional to the magnetic flux density of the magnetic flux interlinking with the detection surface as a W-phase first detection signal V _{HAw indicating the magnetic flux detection result.} Output to the calculation unit 22. The W-phase second magnetic sensor HBw of the W-phase detection unit 21w uses an analog voltage signal proportional to the magnetic flux density of the magnetic flux interlinking with the detection surface as a W-phase second detection signal V _{HBw indicating the magnetic flux detection result.} Output to the calculation unit 22.

The U-phase first detection signal V _HAu , the V-phase first detection signal V _HAv, and the W-phase first detection signal V _HAw have a phase difference of 120 ° in electrical angle from each other. Similarly, the U-phase second detection signal V _HBu , the V-phase second detection signal V _HBv, and the W-phase second detection signal V _HBw have a phase difference of 120 ° in electrical angle from each other. In the following, when it is not necessary to distinguish between the U-phase first detection signal V _HAu , the V-phase first detection signal V _HAv, and the W-phase first detection signal V _HAw , these three detection signals are referred to as the first detection signal. Collectively referred to as V _HA. Similarly, when it is not necessary to distinguish between the U-phase second detection signal V _HBu , the V-phase second detection signal V _HBv, and the W-phase second detection signal V _HBw , these three detection signals are referred to as the second detection signal. Collectively referred to as V _HB.

In the present embodiment, since the three first magnetic sensors HA are provided at intervals of 60 ° along the rotation direction of the rotor 100, the three first detection signals _{VHA having a phase difference of 120 ° in electrical angle from each other are generated.} In order to obtain the signal, a signal obtained by inverting the positive and negative values of the analog voltage signal output from the V-phase first magnetic sensor _HAv is used as the V-phase first detection signal V HAv. Similarly, since the three second magnetic sensors HBs are also provided at intervals of 60 ° along the rotation direction of the rotor 100, in order to obtain _{three second detection signals VHBs having a phase difference of 120 ° in electrical angles from each other.} In addition, a signal obtained by inverting the positive and negative values of the analog voltage signal output from the V-phase second magnetic sensor _HBv is used as the V-phase second detection signal V HBv. When the three first magnetic sensors HA are provided at intervals of 120 ° along the rotation direction of the rotor 100, the analog voltage signal output from the V-phase first magnetic sensor HAv is used as the V-phase first detection signal. It may be used directly as _{V HAv.} Similarly, when the three second magnetic sensors HB are provided at 120 ° intervals along the rotation direction of the rotor 100, the analog voltage signal output from the V-phase second magnetic sensor HBv is detected in the V-phase second detection. It may be used directly as the signal V _HBv.

_{The calculation unit 22 is based on the first detection signal V HA} indicating the magnetic flux detection result obtained from the first magnetic sensor HA _{and the second detection signal V HB} indicating the magnetic flux detection result obtained from the second magnetic sensor HB. The magnetic flux component φm (rotor magnetic flux component) of the rotor 100 and the magnetic flux component φs (fixor magnetic flux component) of the stator 200 are calculated for each detection unit 21. Hereinafter, the calculation principle of the magnetic flux components φm and φs based on the first detection signal V _HA and the second detection signal V _{HB will be described.}

The first detection signal V _HA can be expressed by the following equation (1) as a function of the electric angle θ. Further, the second detection signal V _HB can be expressed by the following equation (2) as a function of the electric angle θ. In the formulas (1) and (2), "φm (θ)" is the magnetic flux component of the rotor 100, and "φs (θ, I)" is the magnetic flux component of the stator 200. “X”, “y”, “j”, and “k” are coefficients that depend on the structure of the motor 10 and the arrangement of the first magnetic sensor HA and the second magnetic sensor HB. Hereinafter, the magnetic flux component of the rotor 100 is referred to as a rotor magnetic flux component, and the magnetic flux component of the stator 200 is referred to as a stator magnetic flux component.

As shown in the formulas (1) and (2), the first detection signal V _HA and the second detection signal V _HB have a rotor magnetic flux component φm (θ) and a stator magnetic flux component φs (θ, I) as magnetic flux components. And include. The rotor magnetic flux component φm (θ) is represented by a periodic function of the electric angle θ. Since the number of pole pairs of the motor 10 in this embodiment is "5", the rotor magnetic flux component φm (θ) is included _{in the first detection signal V HA} and the second detection signal V _{HB obtained during one rotation of the rotor 100.} A periodic wave for 5 cycles is included. In other words, the rotor magnetic flux component φm (θ) is _{a periodic wave having a mechanical angle (rotation angle θ R} ) of 72 ° as one cycle. The periodic wave means a wave having periodicity represented by a periodic function of the electric angle θ.

The stator magnetic flux component φs (θ, I) is represented by a function of the electric angle θ and the coil current I. The stator magnetic flux component φs (θ, I) is a leakage flux (disturbance magnetic flux) generated by the current flowing through the coil 220 of the motor 10. For example, the stator magnetic flux component φs (θ, I) included in the U-phase first detection signal V _HAu and the U-phase second detection signal V _HBu is a function of the U-phase drive current Iu. The stator magnetic flux component φs (θ, I) included in the V-phase first detection signal V _HAv and the V-phase second detection signal V _{HBv is a function of the V-phase drive current Iv.} The stator magnetic flux component φs (θ, I) included in the W-phase first detection signal V _HAw and the W-phase second detection signal V _{HBw is a function of the W-phase drive current Iw.}

The U-phase drive current Iu is a current flowing between the U-phase coil 221 and the V-phase coil 222. The V-phase drive current Iv is a current flowing between the V-phase coil 222 and the W-phase coil 223. The W-phase drive current Iw is a current flowing between the W-phase coil 223 and the U-phase coil 221.

“X” is a coefficient representing the amplitude value of the rotor magnetic flux component φm (θ) included in the first detection signal V _HA , for example, a coefficient corresponding to the distance between the first magnetic sensor HA and the rotor magnet 130. be. “J” is a coefficient representing the amplitude value of the stator magnetic flux component φs (θ, I) included in the first detection signal V _HA , and is, for example, a coefficient corresponding to the distance between the first magnetic sensor HA and the starter 200. Is.

“Y” is a coefficient representing the amplitude value of the rotor magnetic flux component φm (θ) included in the second detection signal V _HB , and is, for example, a coefficient corresponding to the distance between the second magnetic sensor HB and the rotor magnet 130. be. “K” is a coefficient representing the amplitude value of the stator magnetic flux component φs (θ, I) included in the second detection signal V _HB , and is, for example, a coefficient corresponding to the distance between the second magnetic sensor HB and the starter 200. Is.

When the positional relationship between the first magnetic sensor HA and the second magnetic sensor HB satisfies the following two conditions, the inventor of the present application uses equations (1) and (2) to obtain a rotor magnetic flux component φm (θ). And the stator magnetic flux component φs (θ, I) were found to be able to be calculated.
(Condition 1) In each of the three detection units 21, the first magnetic sensor HA faces the rotor magnet 130 in the axial direction, and the second magnetic sensor HB faces the stator 200 in the axial direction.
(Condition 2) In each of the three detection units 21, the first magnetic sensor HA and the second magnetic sensor HB are arranged along the radial direction of the rotor 100.

Specifically, as shown in the following equation (3), first, _{by multiplying the first detection signal V HA} by the first constant C, the calculation result shown on the right side of the equation (3) can be obtained. The first constant C is a value obtained by dividing the coefficient k by the coefficient j. Then, as shown in the following equation (4), _{when the second detection signal V HB} is subtracted from the calculation result obtained by multiplying _{the first detection signal V HA} by the first constant C, the stator magnetic flux component φs (θ). , I) are canceled and only the rotor magnetic flux component φm (θ) remains.

Further, as shown in the following equation (5), first, _{by multiplying the first detection signal VHA} by the third constant D, the calculation result shown on the right side of the equation (5) can be obtained. The third constant D is a value obtained by dividing the coefficient y by the coefficient x. Then, as shown in the following equation (6), when the calculation result obtained by multiplying _{the first detection signal V HA by the third constant D is subtracted from the second detection signal V HB} , the rotor magnetic flux component φm (θ). ) Is canceled, and only the stator magnetic flux component φs (θ, I) remains.

As described above, if the first constant C (= k / j) is obtained in advance by experiment or simulation, the second detection is obtained from the calculation result obtained by multiplying _{the first detection signal VHA by the first constant C.} The rotor magnetic flux component φm can be calculated by subtracting the signal V _HB. Similarly, if the third constant D (= y / x) is obtained in advance by an experiment or simulation, the _{calculation result obtained by multiplying the first detection signal V HA} by the third constant D can be obtained as the second detection signal V. _The stator magnetic flux component φs can be calculated by subtracting from HB. The above is the calculation principle of the rotor magnetic flux component φm and the stator magnetic flux component φs based on the first detection signal V _HA and the second detection signal V _HB.

Based on the above calculation principle, the calculation unit 22 in the present embodiment _{subtracts the second detection signal V HB from the calculation result obtained by multiplying the first detection signal V HA} by the first constant C to obtain the rotor magnetic flux. Calculate the component φm. _{Further, the calculation unit 22 subtracts the calculation result obtained by multiplying the first detection signal V HA} by the third constant D from the second detection signal V _HB based on the above calculation principle, so that the stator magnetic flux component φs Is calculated. Specifically, as shown in FIG. 1, the calculation unit 22 includes a U-phase magnetic flux calculation unit 22u, a V-phase magnetic flux calculation unit 22v, and a W-phase magnetic flux calculation unit 22w. The calculation unit 22 is provided on the circuit board 24.

As shown in FIGS. 1 and 4, the U-phase magnetic flux calculation unit 22u has a U-phase first detection signal V _HAu obtained from the U-phase first magnetic sensor HAu and a U obtained from the U-phase second magnetic sensor HBu. The second phase detection signal V _HBu is input. As shown in FIG. 4, the U-phase magnetic flux calculation unit 22u has a first multiplier 22ua, a first subtractor 22ub, a second multiplier 22uc, and a second subtractor 22ud.

First multiplier 22ua the voltage V _C having an analog voltage value corresponding to the first constant C is multiplied by the U-phase first detection signal V _Hau, and outputs a signal indicating the calculation result to the first subtracter 22ub .. First subtractor 22ub calculates the rotor flux components φm of the U-phase by a signal input from the first multiplier 22ua subtracts the U-phase second detection signal V _HBU, periodic wave signal indicating the calculation result The U-phase rotor magnetic flux signal φmu is output to the state estimation unit 23.

Second multiplier 22uc the voltage V _D having an analog voltage value corresponding to the third constant D by multiplying the U-phase first detection signal V _Hau, and outputs a signal indicating the calculation result to the second subtracter 22ud .. The second subtractor 22ud calculates the U-phase stator magnetic flux component φs by subtracting the signal input from the second multiplier 22uc from the U-phase second detection signal _{VHBu, and the U-phase stator showing the calculation result.} The magnetic flux signal φsu is output to the state estimation unit 23.

As shown in FIGS. 1 and 4, the V-phase magnetic flux calculation unit 22v includes a V-phase first detection signal V _HAv obtained from the V-phase first magnetic sensor HAv and a V obtained from the V-phase second magnetic sensor HBv. The second phase detection signal V _HBv is input. As shown in FIG. 4, the V-phase magnetic flux calculation unit 22v includes a first multiplier 22va, a first subtractor 22vb, a second multiplier 22vc, and a second subtractor 22vd.

First multiplier 22va the voltage V _C having an analog voltage value corresponding to the first constant C multiplies the V-phase first detection signal V _HAV, and outputs a signal indicating the calculation result to the first subtracter 22vb .. The first subtractor 22vb calculates the rotor magnetic flux component φm of the V phase by subtracting the _{V-phase second detection signal V HBv} from the signal input from the first multiplier 22va, and a periodic wave signal showing the calculation result. The V-phase rotor magnetic flux signal φmv is output to the state estimation unit 23.

_{The second multiplier 22vc multiplies the voltage V D} having an analog voltage value corresponding to the third constant D by the V-phase first detection signal V _HAv , and outputs a signal indicating the calculation result to the second subtractor 22vd. .. The second subtractor 22vd calculates the V-phase stator magnetic flux component φs by subtracting the signal input from the second multiplier 22vc from the V-phase second detection signal V _{HBv, and the V-phase stator showing the calculation result.} The magnetic flux signal φsv is output to the state estimation unit 23.

As shown in FIGS. 1 and 4, the W-phase magnetic flux calculation unit 22w has a W-phase first detection signal V _HAw obtained from the W-phase first magnetic sensor HAw and a W obtained from the W-phase second magnetic sensor HBw. The second phase detection signal V _HBw is input. As shown in FIG. 4, the W-phase magnetic flux calculation unit 22w includes a first multiplier 22wa, a first subtractor 22wb, a second multiplier 22wc, and a second subtractor 22wd.

First multiplier 22wa the voltage V _C having an analog voltage value corresponding to the first constant C is multiplied by W phase first detection signal V _HAW, and outputs a signal indicating the calculation result to the first subtracter 22wb .. The first subtractor 22wb calculates the W-phase rotor magnetic flux component φm by subtracting the _{W-phase second detection signal V HBw} from the signal input from the first multiplier 22wa, and a periodic wave signal indicating the calculation result. The W-phase rotor magnetic flux signal φmw is output to the state estimation unit 23.

The second multiplier 22wc multiplies the W-phase first detection signal _{VHAw by the voltage V D} having an analog voltage value corresponding to the third constant D, and outputs a signal indicating the calculation result to the second subtractor 22wd. .. The second subtractor 22wd calculates the W-phase stator magnetic flux component φs by subtracting the signal input from the second multiplier 22wc from the W-phase second detection signal V _{HBw, and the W-phase stator showing the calculation result.} The magnetic flux signal φsw is output to the state estimation unit 23.

In the following, when it is not necessary to distinguish between the U-phase rotor magnetic flux signal φmu, the V-phase rotor magnetic flux signal φmv, and the W-phase rotor magnetic flux signal φmw, these signals are collectively referred to as the rotor magnetic flux signal φm. Further, when it is not necessary to distinguish between the U-phase stator magnetic flux signal φsu, the V-phase stator magnetic flux signal φsv, and the W-phase stator magnetic flux signal φsw, these signals are collectively referred to as the stator magnetic flux signal φs.

The first multipliers 22ua, 22va and 22wa and the second multipliers 22uc, 22vc and 22wc may be the above-mentioned analog multipliers or digital multipliers.
Similarly, the first subtractors 22ub, 22vb and 22wb and the second subtractors 22ud, 22vd and 22wd may be analog subtractors as described above or digital subtractors. When using a digital multiplier and a digital subtractor, if an A / D converter that converts _{three first detection signals V HA} and three second detection signals V _{HB into digital signals is provided.} good. When using a digital multiplier, the digital signals corresponding to the first constant C and the third constant D may be input to the digital multiplier.

In order to transmit the three rotor magnetic flux signals φm and the three stator magnetic flux signals φs according to the rotation angle θ _{R of the rotor 100 to the state estimation unit 23 with the minimum delay time, the calculation unit 22 is hardened as described above.} It is preferably configured by wear (particularly analog circuits). However, if necessary, the function of the calculation unit 22 may be realized by software. That is, a processor such as an MCU (Microcontroller Unit) may be provided on the circuit board 24, and the processor may execute a program based on the above calculation principle to realize the function of the calculation unit 22.

As shown in FIG. 1, the state estimation unit 23 is based on three rotor magnetic flux signals φm (φmu, φmv and φmw) and three stator magnetic flux signals φs (φsu, φsv and φsw) input from the calculation unit 22. Then, the rotation angle θ _R of the rotor 100, the coil currents I (Iu, Iv and Iw), and the torque T are estimated as the state quantities of the motor 10, and the estimated results are used in the control device 30 as the state quantity detection results. Output. The state estimation unit 23 is a processor such as an MCU provided on the circuit board 24. The state estimation unit 23 is a component corresponding to the estimation unit of the present invention. The state estimation unit 23 includes an angle estimation unit 23a, a current estimation unit 23b, and a torque estimation unit 23c.

Three rotor magnetic flux signals φm (φmu, φmv and φmw) obtained from the calculation unit 22 are input to the angle estimation unit 23a. The angle estimation unit 23a estimates (calculates) _{the rotation angle θ R} of the rotor 100 based on the three rotor magnetic flux signals φm (φmu, φmv and φmw), and controls the estimation result as the detection result of the _{rotation angle θ R.} Output to device 30. The angle estimation unit 23 is a component corresponding to the position estimation unit of the present invention. Location estimation algorithm for estimating the rotation angle theta _R of the rotor 100, for example, can be used a position estimation algorithm disclosed in WO 2016/104378. Therefore, the description of the position estimation algorithm is omitted in the present specification.

The algorithm used for estimating the rotation angle θ _R is not limited to the position estimation algorithm disclosed in International Publication No. 2016/10374. If a position estimation algorithm constructed on the premise that it is capable of acquiring three cycles wavy flux detection signal having a predetermined phase difference, may use other algorithms for estimating the rotation angle theta _R.

Three stator magnetic flux signals φs (φsu, φsv and φsw) obtained from the calculation unit 22 are input to the current estimation unit 23b. The current estimation unit 23b determines the coil currents I (Iu, Iv and Iw) based on the three stator magnetic flux signals φs (φsu, φsv and φsw) and the self-inductance and mutual inductance of the motor 10 predetermined as constants. Is estimated, and the estimation result is output to the control device 30 as the detection result of the coil current I.

Specifically, the current estimation unit 23b calculates the U-phase drive current Iu, the V-phase drive current Iv, and the W-phase drive current Iw as the coil current I based on the following equation (7). In the equation (7), "Lu" is the self-inductance of the U-phase coil 221. “Lv” is the self-inductance of the V-phase coil 222. “Lw” is the self-inductance of the W-phase coil 223. “Muv” is the mutual inductance between the U-phase coil 221 and the V-phase coil 222. “Muw” is the mutual inductance between the U-phase coil 221 and the W-phase coil 223.
“Mvu” is the mutual inductance between the V-phase coil 222 and the U-phase coil 221. “Mvw” is the mutual inductance between the V-phase coil 222 and the W-phase coil 223. “Mu” is the mutual inductance between the W-phase coil 223 and the U-phase coil 221. “Mwv” is the mutual inductance between the W-phase coil 223 and the V-phase coil 222.

The torque estimation unit 23c contains the three rotor magnetic flux signals φm (φmu, φmv and φmw) obtained from the calculation unit 22 and the estimation results of the coil currents I (Iu, Iv and Iw) obtained from the current estimation unit 23b. Entered. The torque estimation unit 23c includes three rotor magnetic flux signals φm (φmu, φmv and φmw), an estimation result of the coil current I (Iu, Iv and Iw), and a polar logarithm Np of the rotor magnet 130 predetermined as a constant. The torque T is estimated based on the above, and the estimation result is output to the control device 30 as the detection result of the torque T.

Specifically, the torque estimation unit 23c calculates the torque T based on the following equation (8). Since the motor 10 in this embodiment has 10 rotor magnets 130, the pole logarithm Np is "5".

_{The control device 30 uses the motor 10 based on the detection results of the state quantities (rotation angle θ R} , U-phase drive current Iu, V-phase drive current Iv, W-phase drive current Iw, and torque T) obtained from the state detection device 20. To control. The control device 30 may be provided inside the motor housing of the motor 10, or may be mounted on the outside of the motor housing. The control device 30 rotates the rotor 100 by vector-controlling the U-phase drive current Iu, the V-phase drive current Iv, and the W-phase drive current Iw supplied to the motor 10 based on the detection result of the state quantity. Since vector control is generally known as a control method for the motor 10 which is a three-phase brushless DC motor, detailed description of vector control is omitted in the present specification.

As described above, the state detection device 20 in the present embodiment includes a first magnetic sensor HA facing the rotor magnet 130 in the axial direction of the rotor 100 and a second magnetic sensor HB facing the stator 200 in the axial direction. However, it has at least three detection units 21 provided along the rotation direction of the rotor 100. In each of the detection units 21, the first magnetic sensor HA and the second magnetic sensor HB are arranged along the radial direction of the rotor 100. Further, the state detection device 20 has a rotor magnetic flux component φm and a stator magnetic flux based on _{the first detection signal V HA} obtained from the first magnetic sensor HA and _{the second detection signal V HB} obtained from the second magnetic sensor HB. It has a calculation unit 22 that calculates the component φs for each detection unit 21. _{Further, the state detection device 20 includes a rotation angle θ R} of the rotor 100, coil currents I (Iu, Iv and Iw), and a motor 10 based on the rotor magnetic flux component φm and the stator magnetic flux component φs obtained from the calculation unit 22. A state estimation unit 23 that estimates the torque T of the above as a state quantity is provided.
According to the state detection device 20 configured as described above, it is possible to detect the coil current I and estimate the torque T without a current sensor such as a shunt resistor, and the rotation angle θ _{R without a dedicated sensor magnet.} Can be detected. Therefore, according to the present embodiment, it is possible to provide a state detection device 20 that can be used as an all-in-one type small sensor independent of the control device 30.

Further, in the present embodiment, the calculation unit 22 calculates the rotor magnetic flux component φm by subtracting _{the second detection signal V HB} from the calculation result obtained by multiplying _{the first detection signal V HA by the first constant C.} do.
Thereby, the rotor magnetic flux component φm can be calculated easily and accurately by the combination of the multiplier and the subtractor. As described in the above embodiment, the multiplier and the subtractor can be realized by inexpensive hardware such as an analog circuit or a digital circuit.

Further, in the present embodiment, the calculation unit 22 calculates the stator magnetic flux component φs by subtracting the _{calculation result obtained by multiplying the first detection signal V HA} by the third constant D from the second detection signal V _HB. do.
Thereby, the stator magnetic flux component φs can be calculated easily and accurately by the combination of the multiplier and the subtractor. Similar to the above, the multiplier and the subtractor can be realized by inexpensive hardware such as an analog circuit or a digital circuit.

Further, in the present embodiment, the state estimation unit 23 includes an angle estimation unit 23a, a current estimation unit 23b, and a torque estimation unit 23c. Angle estimator 23a estimates the rotation angle theta _R based on three rotor flux component φm obtained from the calculation unit 22. The current estimation unit 23b estimates the coil current I based on the three stator magnetic flux signals φs obtained from the calculation unit 22 and the self-inductance and mutual inductance of the motor 10 predetermined as constants. The torque estimation unit 23c estimates the torque T based on the three rotor magnetic flux signals φm obtained from the calculation unit 22, the estimation result of the coil current I, and the polar logarithm Np of the rotor magnet 130 predetermined as a constant. do.
_{Thereby, the rotation angle θ R} , the coil current I, and the torque T, which are the state quantities of the motor 10, can be easily and accurately estimated.

[Modification example]
The present invention is not limited to the above-described embodiment, and the configurations described in the present specification can be appropriately combined within a range that does not contradict each other.
For example, instead of the calculation unit 22 described in the above embodiment, the calculation unit 25 in the modified example shown in FIG. 5 may be provided in the state detection device 20. The calculation unit 25 in the modified example calculates the rotor magnetic flux component φm by subtracting _{the first detection signal V HA} from the calculation result obtained by multiplying _{the second detection signal V HB by the second constant E.} Further, the calculation unit 25 calculates the stator magnetic flux component φs by subtracting the _{calculation result obtained by multiplying the second detection signal V HB} by the fourth constant F from the first detection signal V _HA.

As shown in the following equation (9), first, _{by multiplying the second detection signal V HB} by the second constant E, the calculation result shown on the right side of the equation (9) can be obtained. The second constant E is a value obtained by dividing the coefficient j by the coefficient k. Then, as shown in the following equation (10), _{when the first detection signal V HA} is subtracted from the calculation result obtained by multiplying _{the second detection signal V HB} by the second constant E, the stator magnetic flux component φs (θ). , I) are canceled and only the rotor magnetic flux component φm (θ) remains.

Further, as shown in the following equation (11), first, _{by multiplying the second detection signal V HB} by the fourth constant F, the calculation result shown on the right side of the equation (11) can be obtained. The fourth constant F is a value obtained by dividing the coefficient x by the coefficient y. Then, as shown in the following equation (12), when the calculation result obtained by multiplying _{the second detection signal V HB by the fourth constant F is subtracted from the first detection signal V HA} , the rotor magnetic flux component φm (θ). ) Is canceled, and only the stator magnetic flux component φs (θ, I) remains.

As described above, if the second constant E (= j / k) is obtained in advance by experiment or simulation, the first detection is performed from the calculation result obtained by multiplying _{the second detection signal V HB by the second constant E.} The rotor magnetic flux component φm can be calculated by subtracting the signal V _HA. Similarly, if the fourth constant F (= x / y) is obtained in advance by an experiment or simulation, the _{calculation result obtained by multiplying the second detection signal V HB} by the fourth constant F can be obtained as the first detection signal V. _The stator magnetic flux component φs can be calculated by subtracting from HA. As shown in FIG. 5, the calculation unit 25 in the modified example includes a U-phase magnetic flux calculation unit 25u, a V-phase magnetic flux calculation unit 25v, and a W-phase magnetic flux calculation unit 25w.

_{The U-phase first detection signal V HAu} obtained from the U-phase first magnetic sensor _{HAu and the U-phase second detection signal V HBu} obtained from the U-phase second magnetic sensor HBu are input to the U-phase magnetic flux calculation unit 25u. Will be done. The U-phase magnetic flux calculation unit 25u has a first multiplier 25ua, a first subtractor 25ub, a second multiplier 25uc, and a second subtractor 25ud.

First multiplier 25ua the voltage V _E having an analog voltage value corresponding to the second constant E by multiplying the U-phase second detection signal V _HBU, and outputs a signal indicating the calculation result to the first subtracter 25ub .. First subtractor 25ub calculates the rotor flux components φm of the U-phase by a signal input from the first multiplier 25ua subtracts the U-phase first detection signal V _Hau, periodic wave signal indicating the calculation result The U-phase rotor magnetic flux signal φmu is output to the state estimation unit 23.

Second multiplier 25uc the voltage V _F having an analog voltage value corresponding to the fourth constant F multiplies the U-phase second detection signal V _HBU, and outputs a signal indicating the calculation result to the second subtracter 25ud .. The second subtractor 25ud calculates the U-phase stator magnetic flux component φs by subtracting the signal input from the second multiplier 25uc from the U-phase first detection signal _{VHAu, and the U-phase stator showing the calculation result.} The magnetic flux signal φsu is output to the state estimation unit 23.

_{The V-phase first detection signal V HAv} obtained from the V-phase first magnetic sensor HAv and the V-phase second detection signal V HBv obtained from the V-phase second magnetic sensor HBv are input to the _{V-phase magnetic flux calculation unit 25v.} Will be done. The V-phase magnetic flux calculation unit 25v includes a first multiplier 25va, a first subtractor 25vb, a second multiplier 25vc, and a second subtractor 25vd.

First multiplier 25va the voltage V _E having an analog voltage value corresponding to the second constant E multiplies the V-phase second detection signal V _HBV, and outputs a signal indicating the calculation result to the first subtracter 25vb .. First subtractor 25vb calculates the rotor flux components φm of the V-phase by subtracting the V-phase first detection signal V _HAV from a signal input from the first multiplier 25VA, periodic wave signal indicating the calculation result The V-phase rotor magnetic flux signal φmv is output to the state estimation unit 23.

Second multiplier 25vc the voltage V _F having an analog voltage value corresponding to the fourth constant F multiplies the V-phase second detection signal V _HBV, and outputs a signal indicating the calculation result to the second subtracter 25vd .. The second subtractor 25vd calculates the V-phase stator magnetic flux component φs by subtracting the signal input from the second multiplier 25vc from the V-phase first detection signal _{VHAv, and the V-phase stator showing the calculation result.} The magnetic flux signal φsv is output to the state estimation unit 23.

_{The W-phase first detection signal V HAw} obtained from the W-phase first magnetic sensor _{HAw and the W-phase second detection signal V HBw} obtained from the W-phase second magnetic sensor HBw are input to the W-phase magnetic flux calculation unit 25w. Will be done. The W-phase magnetic flux calculation unit 25w includes a first multiplier 25wa, a first subtractor 25wb, a second multiplier 25wc, and a second subtractor 25wd.

First multiplier 25wa the voltage V _E having an analog voltage value corresponding to the second constant E by multiplying the W-phase second detection signal V _HBW, and outputs a signal indicating the calculation result to the first subtracter 25wb .. First subtractor 25wb calculates the rotor flux components φm of the W phase by subtracting the W-phase first detection signal V _HAW from a signal input from the first multiplier 25Wa, periodic wave signal indicating the calculation result The W-phase rotor magnetic flux signal φmw is output to the state estimation unit 23.

Second multiplier 25wc the voltage V _F having an analog voltage value corresponding to the fourth constant F multiplies the W-phase second detection signal V _HBW, and outputs a signal indicating the calculation result to the second subtracter 25wd .. The second subtractor 25wd calculates the W-phase stator magnetic flux component φs by subtracting the signal input from the second multiplier 25wc from the W-phase first detection signal _{VHAw, and the W-phase stator showing the calculation result.} The magnetic flux signal φsw is output to the state estimation unit 23.

Also in the modified state detection device 20 including the calculation unit 25 as described above, the first detection signal V _{HA obtained from the first magnetic sensor HA and the second detection signal V HB} obtained from the second magnetic sensor HB The rotor magnetic flux component φm and the stator magnetic flux component φs can be calculated based on the above.

1 ... motor unit, 10 ... motor, 20 ... state detection device, 21 ... detection unit, 21u ... U phase detection unit, 21v ... V phase detection unit, 21w ... W phase detection unit, 22, 25 ... calculation unit, 22u, 25u ... U-phase magnetic flux calculation unit, 22v, 25v ... V-phase magnetic flux calculation unit, 22w, 25w ... W-phase magnetic flux calculation unit, 22ua, 22va, 22wa, 25ua, 25va, 25wa ... First multiplier, 22ub, 22vb, 22wb , 25ub, 25vb, 25wb ... 1st subtractor, 22uc, 22vc, 22wc, 25uc, 25vc, 25wc ... 2nd multiplier, 22ud, 22vd, 22wd, 25ud, 25vd, 25wd ... 2nd subtractor, 23 ... State estimation Unit (estimation unit), 23a ... angle estimation unit (position estimation unit), 23b ... current estimation unit, 23c ... magnetic flux estimation unit, 24 ... circuit board, 24a ... shaft insertion hole, 24b ... circuit board plate surface, 30 ... Control device, 100 ... rotor (rotor), 110 ... rotor core, 120 ... rotor shaft, 130 ... rotor magnet (permanent magnet), 200 ... stator (fixer), 210 ... stator core, 211 ... yoke, 212 ... teeth, 220 ... Coil, 221 ... U-phase coil, 222 ... V-phase coil, 223 ... W-phase coil, 220 ... Coil, HA ... 1st magnetic sensor, HAu ... U-phase 1st magnetic sensor, HAv ... V-phase 1st magnetic sensor, HAw ... W phase 1st magnetic sensor, HB ... 2nd magnetic sensor, HBu ... U phase 2nd magnetic sensor, HBv ... V phase 2nd magnetic sensor, HBw ... W phase 2nd magnetic sensor

Claims (7)

1. A state detection device for detecting the state quantity of a motor including a stator having a coil and a rotor having a permanent magnet.
   It has a first magnetic sensor facing the permanent magnet in the axial direction of the rotor and a second magnetic sensor facing the stator in the axial direction, and is provided at least along the rotation direction of the rotor. Three detectors and
   The rotor magnetic flux component and the stator magnetic flux component are based on the first detection signal indicating the magnetic flux detection result obtained from the first magnetic sensor and the second detection signal indicating the magnetic flux detection result obtained from the second magnetic sensor. With a calculation unit that calculates for each detection unit,
   Estimating the rotation position of the rotor, the coil current flowing through the coil, and the torque of the motor as the state quantities based on the rotor magnetic flux component and the stator magnetic flux component obtained from the calculation unit. Department and
   With
   In each of the detection units, the first magnetic sensor and the second magnetic sensor are arranged along the radial direction of the rotor.
   State detector.
2. The calculation unit calculates the rotor magnetic flux component by subtracting the second detection signal from the calculation result obtained by multiplying the first detection signal by the first constant.
   The state detection device according to claim 1.
3. The calculation unit calculates the rotor magnetic flux component by subtracting the first detection signal from the calculation result obtained by multiplying the second detection signal by the second constant.
   The state detection device according to claim 1.
4. The calculation unit calculates the stator magnetic flux component by subtracting the calculation result obtained by multiplying the first detection signal by the third constant from the second detection signal.
   The state detection device according to any one of claims 1 to 3.
5. The calculation unit calculates the stator magnetic flux component by subtracting the calculation result obtained by multiplying the second detection signal by the fourth constant from the first detection signal.
   The state detection device according to any one of claims 1 to 3.
6. The estimation unit
   A position estimation unit that estimates the rotation position based on the rotor magnetic flux component obtained from the calculation unit, and a position estimation unit.
   A current estimation unit that estimates the coil current based on the stator magnetic flux component obtained from the calculation unit and the self-inductance and mutual inductance of the motor that are predetermined as constants.
   The torque is estimated based on the rotor magnetic flux component obtained from the calculation unit, the estimation result of the coil current obtained from the current estimation unit, and the number of pole pairs of the permanent magnet predetermined as a constant. Torque estimation unit and
   Have,
   The state detection device according to any one of claims 1 to 5.
7. A motor including a stator with a coil and a rotor with a permanent magnet,
   The state detection device according to any one of claims 1 to 6, which detects the state amount of the motor.
   A control device that controls the motor based on the detection result of the state quantity obtained from the state detection device, and
   Motor unit with.

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