JP2014033543A - Axial type magnetic levitation motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an axial type magnetic levitation motor which can maintain a rotation center axis of a rotor in the axial type magnetic levitation motor in a prescribed position.SOLUTION: The axial type magnetic levitation motor includes: a rotor rotating with a rotation center axis arranged in a Z-axis direction of an orthogonal coordinate system; one side and other side stators arranged separately on one side and the other side of the rotor along a Z-axis; and a control section for supplying control current to the one side stator. A plurality of permanent magnets forming a magnetic pole are arranged in the rotor. The control section supplies the one side and other side stators with control current for controlling rotation torque generated in the rotor and controlling a position of the rotation center axis of the rotor so as to be maintained in a prescribed position.

Description

  The present invention relates to an axial type magnetic levitation motor.

  2. Description of the Related Art A magnetic levitation motor that rotates a rotor in a non-contact state while magnetically levitating along the rotation center axis by the action of magnetism is known. The magnetic levitation motor is used for a high-speed rotation mechanism such as a high-speed spindle for a machine tool because of a structure that does not use a mechanical bearing, and can be further reduced in size, for example, a centrifugal pump for an artificial heart in the medical field, for example. Application to motors is expected.

  As a structure of a magnetic levitation motor, for example, an axial type magnetic levitation motor is known in which a stator winding arranged in a stator is arranged so as to face a permanent magnet provided in a rotor. Furthermore, a centrifugal pump using an axial type magnetic levitation motor in which a centrifugal pump mechanism is assembled to the rotor is also known.

  An example of an axial type magnetic levitation motor and a centrifugal pump using the axial type magnetic levitation motor are disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2010-279230) and Patent Document 2 (Japanese Patent Laid-Open No. 2001-268881). .

JP 2010-279230 A JP 2001-268881 A

  In a centrifugal pump using the axial type magnetic levitation motor and the axial type magnetic levitation motor described in Patent Document 1, the rotation center of the rotor is along the Z axis of an orthogonal coordinate system having an X axis, a Y axis, and a Z axis. When the shaft is placed, the position of the rotation center axis of the rotor on the X axis and the Y axis may deviate from the target position due to the deviation of the rotor center of gravity, external force, or magnetic force fluctuation. Patent Document 1 does not mention at all the presentation of the problem about the position of the rotation center axis of the rotor of the axial type magnetic levitation motor in the X axis and the Y axis deviating from the target position and the solution to this problem, There is no disclosure of suggestions. Further, in the centrifugal pump using the axial type magnetic levitation motor and the axial type magnetic levitation motor described in Patent Document 2, in order to suppress the vibration of the rotation center axis of the rotor that is the rotor, the edge effect of the rotor is used. It is what you use. The method using the edge effect of the rotor is a method of statically supporting in the radial direction, and sufficient control for maintaining the rotation center axis of the rotor at a predetermined position cannot be performed.

  Since the axial type magnetic levitation motor does not have a structure in which the rotor is mechanically supported, as described above, the position of the rotation center axis of the rotor causes the rotation angle of the rotor to change due to the deviation of the rotor center of gravity, external force, or magnetic force fluctuation. There is a risk that the X axis and the Y axis will shift according to the change, and it is necessary to maintain the rotation center axis of the rotor at a predetermined position on the X axis and the Y axis.

  The problem to be solved by the present invention is to provide an axial magnetic levitation motor capable of maintaining the rotation center axis of a rotor at a predetermined position.

  An axial magnetic levitation motor according to a first aspect of the present invention for solving the above problems includes a rotor that rotates about a rotation center axis provided in the Z-axis direction of an orthogonal coordinate system including an X-axis, a Y-axis, and a Z-axis. A one-sided stator that is spaced apart from one side of the rotor along the Z-axis and includes at least one winding composed of a plurality of coils, and the other side of the rotor along the Z-axis And a control unit for supplying control current to the winding of the one-side stator and the winding of the other-side stator. Each of the one side stator and the other side stator further includes a stator core having a plurality of salient poles, and each of the salient poles of each stator core has the coil constituting the winding. Of the rotor A plurality of permanent magnets that form magnetic poles of the rotor are disposed on the surface facing the one-side stator and the surface facing the other-side stator, respectively, and the one-side stator and the other-side stator each include Control the rotational torque generated in the rotor from the control unit to one of the windings, and maintain the position of the coordinates of the rotation center axis of the rotor by the X axis and the Y axis at a predetermined position. The control current to be supplied is supplied.

  An axial magnetic levitation motor according to a second invention for solving the above-mentioned problem is the axial magnetic levitation motor according to the first invention, wherein the control unit controls a rotational torque generated in the rotor. And a rotation center axis position control value for controlling a position of coordinates of the rotor by the X axis and the Y axis, and the calculated rotation torque control value and the rotation center axis position control value. The control current is generated on the basis of the control signal, and the control current is supplied to at least one of the windings of the one-side stator and the other-side stator, respectively.

  An axial type magnetic levitation motor according to a third aspect of the present invention for solving the above-mentioned problems is the axial type magnetic levitation motor according to the second aspect of the present invention, wherein the one-side stator is based on the calculated rotational torque control value. And the number of poles for generating a rotating magnetic field that each of the other side stators has is the same as the number of poles P created by the magnets of the rotor, and the one side stator and the ones on the basis of the calculated rotation center axis position control value The number M of magnetic poles for generating a rotating magnetic field of each of the other side stators has a relationship of M = P ± 2 with respect to the number of poles P created by the magnet of the rotor.

  An axial type magnetic levitation motor according to a fourth aspect of the present invention for solving the above-mentioned problems is the axial type magnetic levitation motor according to the first aspect of the invention, wherein the one-side stator and the other-side stator are each at least a first one. A rotation torque control value for controlling a rotation torque generated in the rotor, and a position of coordinates by the X axis and the Y axis of the rotation center axis of the rotor. A rotation center axis position control value for controlling the rotation torque, and the control unit sends the control current to the first winding of the one-side stator and the other-side stator based on the calculated rotation torque control value, respectively. And supplying the control current to the second windings of the one-side stator and the other-side stator based on the calculated rotation center axis position control value. The number of poles rotating magnetic field and M made by the number of poles of the magnets of the rotor make is P, the relationship of M = P ± 2 is satisfied, characterized in that.

  An axial type magnetic levitation motor according to a fifth aspect of the present invention for solving the above problem is the axial type magnetic levitation motor according to the second aspect of the present invention, wherein the control unit includes an arithmetic processing unit and an output unit, The arithmetic processing unit, based on the measured position of the rotation center axis of the rotor and the measured inclination of the rotor, the coordinate position of the rotation center axis of the rotor by the X axis and the Y axis, and the rotor A rotation center axis position control value and an inclination control value for controlling the inclination of the first side stator and the inclination control value based on the calculated rotation center axis position control value and the inclination control value. The control current is supplied to each of the windings of the other side stator.

  An axial magnetic levitation motor according to a sixth invention for solving the above-mentioned problems is the axial magnetic levitation motor according to the fourth invention, wherein the control unit has an arithmetic processing unit and an output unit. The arithmetic processing unit, based on the measured position of the rotation center axis of the rotor and the measured inclination of the rotor, the coordinate position of the rotation center axis of the rotor by the X axis and the Y axis and the A rotation center axis position control value and an inclination control value for controlling the inclination of the rotor are calculated, and the output unit, based on the calculated rotation center axis position control value and the inclination control value, The control current for controlling the position of the rotation center axis of the rotor and the inclination of the rotor is supplied to the second winding of the other side stator, respectively.

  An axial type magnetic levitation motor according to a seventh aspect of the present invention for solving the above problem is the axial type magnetic levitation motor according to the fifth aspect of the invention or the sixth aspect of the invention. The one side for controlling the position of the rotation center axis of the rotor and the inclination of the rotor based on the measured value of the inclination of the rotor around the axis and the measured value of the position of the rotation center axis in the Y-axis direction The rotation center axis position control value and the tilt control value of the stator and the other side stator are respectively calculated.

  An axial type magnetic levitation motor according to an eighth aspect of the present invention for solving the above problems is the axial type magnetic levitation motor according to the fifth aspect of the invention or the sixth aspect of the invention. The one side for controlling the position of the rotation center axis of the rotor and the inclination of the rotor based on the measured value of the inclination of the rotor around the axis and the measured value of the position of the rotation center axis in the X-axis direction. The rotation center axis position control value and the tilt control value of the stator and the other side stator are respectively calculated.

  According to the present invention, the rotation center axis of the rotor of the axial type magnetic levitation motor can be maintained at a predetermined position.

It is explanatory drawing explaining the structure of an axial type magnetic levitation motor. 4 is an explanatory diagram for explaining magnetic poles created by a permanent magnet 32 provided on a rotor 30. FIG. It is AA sectional drawing of FIG. It is explanatory drawing which shows the relationship of the magnetic pole which the magnetic pole of a rotor and the 2nd coil | winding of one side stator produce. It is explanatory drawing explaining control of the rotational force centering on a Y-axis. It is explanatory drawing which shows the specific structure which implement | achieves the inclination control of a rotor with an axial type magnetic levitation motor. It is explanatory drawing which shows the relationship between the pole number of a rotor, and the pole number which a stator winding | coil makes. It is a connection diagram which shows the connection state of the coil for producing | generating a 2 pole magnetic pole with 6 salient poles. It is explanatory drawing explaining the magnetic pole generated by the connection of FIG. It is a connection diagram which shows the connection state of the coil for producing | generating a 4 pole magnetic pole by 6 salient poles. It is explanatory drawing explaining the magnetic pole generated by the connection of FIG. It is explanatory drawing which shows the specific structure which implement | achieves radial direction control with an axial type magnetic levitation motor. It is explanatory drawing which shows the number of poles of a rotor, the number of poles which a stator coil | winding makes, and the direction of magnetic force. It is explanatory drawing which shows the principle of the inclination control of a rotor with an axial type magnetic levitation motor. It is explanatory drawing which shows the principle of the radial direction control of a rotor with an axial type magnetic levitation motor. It is a control block diagram for axial direction position and rotation speed control of a rotor. It is a control block diagram for inclination and radial position control.

  In this specification, the rotation center axis is a straight line that becomes the center of the rotation motion, and the rotation center axis of the rotor is the center line that becomes the center of the rotation motion of the rotor, and the rotor rotates around this center line. Do exercise.

1. A mechanical configuration of the axial type magnetic levitation motor 100 will be described below with reference to the drawings. FIG. 1 is an explanatory view illustrating the configuration of an axial magnetic levitation motor 100 according to an embodiment of the present invention. The axial type magnetic levitation motor 100 has a rotation center axis of the rotor 30 arranged along the Z axis of an orthogonal coordinate system including the X axis, the Y axis, and the Z axis, and is arranged on one side along the Z axis. The stator 10 and the other stator 20 disposed on the other side along the Z-axis are provided, and the rotor 30 is disposed between the one-side stator 10 and the other-side stator 20 in the Z-axis direction. Has been.

  In this embodiment, the housing that covers the external appearance of the axial type magnetic levitation motor 100 is removed so that the inside structure can be seen. The one-side stator 10 and the other-side stator 20 are mechanically fixed to the housing (not shown), but the rotor 30 is not mechanically supported. The rotor 30 is moved in the Z-axis direction by magnetic force. It is controlled to be maintained at a predetermined position. Further, the inclination of the rotor 30 and the position of the rotation center axis on the X axis and the Y axis are controlled by a method described later so as to be maintained at a predetermined position.

  Although the axial type magnetic levitation motor 100 shown in FIG. 1 is assumed to be used for a centrifugal pump used in an artificial heart, the use of the axial type magnetic levitation motor 100 is not limited to this, and various pumps can be used. Of course, it can be used as a drive motor, and of course, it can be used as a drive motor for devices other than pumps. For example, as an application other than the pump, the axial type magnetic levitation motor 100 according to the present invention can be used for a mechanism that rotates at high speed, and the mechanical bearing is not used by applying the present invention to a high-speed rotation motor. There is a big effect.

  As described above, by not using a bearing mechanism that mechanically supports the rotor 30 so as to be rotatable, when used in the above-described artificial heart pump, the volume of the entire pump can be reduced as compared with other systems. There is. Also, mechanical bearings cause various problems when used for a long period of time, such as lubrication problems and frictional heat problems. The problems caused by these mechanical bearings are not limited to mechanical problems, but may include health problems such as the risk of blood coagulation. Since the rotor 30 can be stably supported by the magnetic force by the control method described below, in this embodiment, various problems caused by the above-described mechanical bearing can be solved.

  In addition, there are various problems related to mechanical bearings in an apparatus that rotates at high speed. Since the rotor 30 shown in the present embodiment is not mechanically supported but supported by a magnetic force, there is a great effect of suppressing the occurrence of various problems related to the mechanical bearing. For this reason, the axial type magnetic levitation motor 100 shown in FIG. 1 has a great effect when used in a mechanism that rotates at high speed. The motor of the present embodiment can greatly suppress the amount of heat that should be generated if the rotor 30 is rotating at high speed if it is a mechanical bearing. Further, since the rotor 30 floats in the air, the permanent magnet described below provided on the surface of the rotor 30 is more easily cooled by the air around the rotor.

1.1 About the structure of the one-side stator 10 or the other-side stator 20 The one-side stator 10 located in the positive direction on the Z-axis and the other-side stator 20 located in the negative direction on the Z-axis shown in FIG. However, the mechanical structures are substantially the same. The one-side stator 10 and the other-side stator 20 have stator cores 15 and 25 for forming magnetic paths, respectively. The stator core 15 or the stator core 25 is provided with, for example, six salient poles described below. A first coil 112 and a second coil 122 are wound around the six salient poles provided on the stator core 15. In addition, since it will become complicated if a code | symbol is attached | subjected to all the coils of illustration wound by the 6 salient poles, the code | symbol of 112 or 122 is attached as a representative. The six first coils 112 wound around the protrusions of the stator core 15 constitute the first winding 11, and the first winding 11 generates a rotating magnetic field and rotates the rotor 30 including the permanent magnet 32. It acts to generate. Further, the first winding 11 is used for control for maintaining the position of the rotor 30 at a predetermined position on the Z-axis.

  In addition, six second coils 122 are provided flat on the protrusions of the stator core 15 to form the second winding 12, and the second winding 12 performs control to suppress the inclination of the rotor 30. At the same time, it is used to perform control to maintain the positions of the rotation center axis of the rotor 30 on the X axis and the Y axis at predetermined positions.

  Similarly, a first coil 221 and a second coil 222 are wound around six salient poles provided on the stator core 25. The six first coils 221 constitute a first winding 21, and the first winding 21 is used to generate a rotating magnetic field and generate a rotating torque in the rotor 30 including the permanent magnet 33, and On the Z axis, it is used for control to maintain the position of the rotor 30 at a predetermined position.

1.2 Structure of Rotor 30 The rotor 30 has two rotor yokes facing each other with a magnetic gap, and permanent magnets 32 are respectively provided on the surfaces of the rotor yoke facing the one side stator 10 and the other side stator 20. A plurality of 33 are arranged. The permanent magnet 32 and the permanent magnet 33 form a rotor magnetic pole together with each rotor yoke made of a magnetic material, and generate rotational torque based on the rotating magnetic field created by the first winding 11 and the first winding 21 described above. When the rotor is an impeller of a centrifugal pump, a plurality of impellers 31 are provided in the gap between the rotor yokes, and the impeller 31 operates as a centrifugal pump by covering the outer periphery with a pump case. In FIG. 1, the pump case is not shown in order to explain the structure of the rotor 30. The pump case houses the rotor 30 and has the same shape as the pump casing described in Japanese Patent Application Laid-Open No. 2010-279230, for example, with reference numeral 51.

2. In order to perform the control described above for the configuration of the control unit 70, a control current is supplied from the control unit 70 to the first winding 11, the second winding 12, the first winding 21, and the second winding 22. The control unit 70 measures the state of the controlled object, the calculation processing unit 50 that calculates the control value based on the measurement result of the measurement unit 40, and the first winding 11 and the first winding based on the calculation result of the calculation processing unit 50. And an output unit 60 for supplying control current to the two windings 12, the first winding 21, and the second winding 22, respectively.

  The measuring unit 40 is a rotation angle sensor of the rotor magnetic pole for measuring the position of the magnetic pole created by the permanent magnet 32 and the permanent magnet 33 of the rotating rotor 30, and the rotation of the rotor 30 for measuring the rotation speed of the rotor 30. A speed sensor, a rotor position sensor that measures the position and inclination of the rotor 30 on the Z axis, and a rotation center axis position sensor that measures where the rotation center axis of the rotor 30 is located in the XY coordinate system are provided. Yes.

  Here, the rotation angle sensor for measuring the magnetic pole position created by the permanent magnet 32 or the permanent magnet 33 of the rotor 30 may output a signal representing the rotation angle for each fine rotation angle corresponding to the accuracy required for the control. However, the magnetic pole position of the rotor 30 may be measured at a rough angle, and an interpolation operation may be performed based on the rotational speed of the rotor 30 or acceleration / deceleration of the rotational speed to measure a fine angle representing the magnetic pole position of the rotor 30. Further, the rotation angle and the rotation angle may be estimated from the counter electromotive force generated in the stator coil without depending on the sensor.

  Further, the rotational speed sensor of the rotor may be a sensor that obtains the rotational speed by arithmetic processing using a sensor output representing the magnetic pole of the rotor 30. Since the sensor that measures the magnetic pole position of the rotor 30 outputs a measurement value based on the rotation of the rotor 30, the rotation speed is obtained by, for example, counting pulses that are measurement values output by the rotation angle sensor within a certain time. May be. Alternatively, the time required for the rotor 30 to rotate at a predetermined rotation angle may be measured, and the rotation speed may be calculated from the measured value.

  The arithmetic processing unit 50 calculates the current value to be supplied so that the measurement value of the control target related to the rotor 30 obtained based on the measurement result of the measurement unit 40 becomes the control target value. The output unit 60 supplies a control current based on the calculated current value. The specific calculation processing contents of the calculation processing unit 50 will be described later.

3. FIG. 2 is an explanatory diagram for explaining the magnetic poles produced by the permanent magnets 32 provided on the rotor 30. FIG. 2 shows a state of magnetic poles formed by a permanent magnet 32 provided on one side yoke of the impeller 31 of the rotor 30. 3 is a cross-sectional view taken along the line AA in FIG. Note that the other yoke of the impeller 31 has the same structure and shape, and the same magnetic pole is produced. The magnetic poles made on the one-side yoke will be described on behalf of the magnetic poles made on the rotor 30 by permanent magnets. Since the magnetic pole of the one side yoke and the magnetic pole of the other side yoke are technically the same, the description of the magnetic pole made of the other side yoke of the impeller 31 is omitted.

  2 and 3, the one-side yoke 312 is made of, for example, magnetic soft iron, which is a magnetic material, and a hole 314 is formed at the center. This hole is used as an inlet for a fluid such as blood flowing into the centrifugal pump, and operates even if it does not function as a motor. In this embodiment, four permanent magnets 32a, 32b, 32c, and 32d are fixed to the surface of the one side yoke 312 that faces the stator core 15 of the one side yoke 312. These permanent magnets 32 are made of neodymium or a ferrite material. The neodymium material has a larger residual magnetic flux density and holding force than the ferrite material, and can generate a large force. The material of the permanent magnet 32 is not limited to the above, and any material may be used.

  By using four permanent magnets 32a, 32b, 32c, and 32d, it is possible to generate four magnetic poles in this embodiment. Even a magnetic pole other than the four poles described below can be achieved by changing the number of magnetic poles. In addition, when the size of the surface which fixes a magnetic pole is the same, the size of the permanent magnet which comprises one pole becomes small as the number of magnetic poles increases.

  In FIG. 2, the permanent magnets 32a, 32b, 32c, and 32d that create the four-pole magnetic poles are arranged without gaps, but the present invention is not limited to this, and gaps may be provided between the permanent magnets constituting the magnetic poles.

  FIG. 2 shows the state of the magnetic poles on the side of the stator core 15 of the permanent magnet 32 of the rotor 30. The permanent magnet 32a and the permanent magnet 32c constituting the permanent magnet 32 have the S pole on the stator core 15 side and the back surface thereof. The side of the side yoke 312 is the N pole. On the other hand, in the permanent magnet 32b and the permanent magnet 32d, the surface on the stator iron core 15 side is the N pole, and the surface on the one side yoke 312 side that is the back surface is the S pole. In this specification, the magnetic poles of the permanent magnets provided on the rotor 30 are indicated by the magnetic poles of the permanent magnet surface on the stator core side.

4). FIG. 4 and FIG. 5 are explanatory diagrams for explaining the concept of control for controlling the inclination of the rotor 30 generated around the Y axis to a target value. The inclination of the rotor 30 has an inclination component centered on the Y axis and an inclination component centered on the X axis. First, for easy understanding, control of the inclination component centered on the Y axis will be described. . It is possible to control the tilt component with the X axis as the center with the same concept, and by combining both the tilt control with the Y axis as the center and the tilt control with the X axis as the center, all the tilts of the rotor 30 can be controlled. Corresponding control becomes possible. Further, the control with respect to the inclination of the rotor 30 can be performed by any one of the control using the second winding 12 of the one-side stator 10 and the control using the second winding 22 of the other-side stator 20. It is also possible to use both.

  The control by the second winding 12 of the one-side stator 10 and the control by the second winding 22 of the other-side stator 20 are technically the same, and in order to avoid complicated explanation, Control by the winding 12 will be described. That is, the inclination control of the rotor 30 will be described in relation to the magnetic pole created by the permanent magnet 32 on one side of the rotor 30 and the magnetic pole created by the second winding 12 of the one-side stator. The same applies to the tilt control based on the magnetic pole created by the permanent magnet 33 and the magnetic pole created by the second winding 22 of the other stator.

  The rotor 30 rotates with a predetermined phase relationship based on the rotating magnetic field generated by the first winding 11 of the one-side stator 10. In this embodiment, since the inclination of the rotor 30 is controlled by the control current supplied to the second winding 12, the polarity of the magnetic pole of the rotor 30 and the polarity of the magnetic pole formed by the second winding 12 of the one-side stator 10 at a certain moment. FIG. 4 shows the relationship. FIG. 4 shows a case where the permanent magnet 32 provided on the rotor 30 has four magnetic poles and the second winding 12 has two magnetic poles. As will be described below, a relationship of M = P ± 2 is established, where P is the number of magnetic poles of the rotor 30 and M is the number of magnetic poles formed by the second winding 12. In this embodiment, the number of magnetic poles produced by the first winding 11 is the same as the number of magnetic poles produced by the permanent magnet 32 of the rotor 30.

  By making the number of magnetic poles produced by the first winding 11 the same as the number of magnetic poles produced by the permanent magnet 32 of the rotor 30, a large torque can be generated. The number of magnetic poles created by the permanent magnet 32 is preferably the same, but this is not necessarily limited to this. The number of magnetic poles created by the first winding 11 and the number of magnetic poles created by the permanent magnet 32 of the rotor 30 are made different. May be. The same applies to the other stator 20.

  In FIG. 4, the second winding 12 and the permanent magnet 32 are actually arranged so as to face each other in the Z-axis direction, but the state of the magnetic pole created by the one-side permanent magnet of the rotor 30 is schematically illustrated on the inner side. And the state of the magnetic pole which the 2nd coil | winding 12 produces on the outer periphery is described. FIG. 5 is an explanatory diagram for explaining the relationship between the arrangement state of the magnetic poles shown in FIG. 4 in the Z-axis direction and the rotational force about the Y-axis generated by the magnetic poles, and one side arranged on the Z-axis. The relationship between the magnetic pole created by the permanent magnet 32 and the magnetic pole created by the second winding 12 is shown.

  On the right side of FIG. 4 and FIG. 5 (the positive side of the X axis), the magnetic pole created by the permanent magnet 32d and the magnetic pole created by the second winding 12 are each N poles. On the right side, a repulsive force 41 is generated. On the other hand, a suction force 42 is generated in the left direction (the negative side of the X axis). Since the second winding 12 is mechanically fixed as described above, a clockwise rotational force about the Y axis is generated in the rotor 30 by the magnetic pole created by the second winding 12. Since the magnitude of this rotational force is determined based on the control current supplied from the control unit 70 to the second winding 12, the value of the rotational force is controlled by appropriately controlling the value of the control current supplied to the second winding 12. The size can be controlled. When the control current value supplied to the second winding 12 is a negative value, that is, by shifting the phase by π, it is possible to generate a magnetic pole having a polarity opposite to that shown in FIG. The rotational force can be generated.

  In this embodiment, for example, by shifting the phase of the current supplied to the second winding 12 and the permanent magnet 32 of the rotor 30 by π / 2, a rotational force about the X axis can be generated. In this way, by controlling the magnitude and phase of the rotating magnetic field created by the second winding 12 with respect to the magnetic pole created by the permanent magnet 32, the rotor 30 is centered on the X axis and the Y axis shown in FIGS. It is possible to freely generate a rotational force that combines the acting rotational forces. The inclination of the rotor 30 with respect to the X axis and the Y axis is measured by a sensor, and based on the calculation, the rotational force for returning the inclination of the rotor 30 to the target state is calculated based on the deviation of the measured value from the inclination target value. By supplying the control current to the second winding 12, it is possible to perform control to maintain the inclination of the rotor 30 at the control target value.

  4 and 5, only one side of the permanent magnet 32 and the permanent magnet 33 disposed on the one-side stator 10, the other-side stator 20, and the rotor 30 has been described. Similarly, the magnet 33 can generate a rotational force about the X axis and the Y axis. Since both the inclination correction force controlled by the one-side stator 10 and the inclination correction force controlled by the other-side stator 20 act on the rotor 30, various combinations of the control by the one-side stator 10 and the control by the other-side stator 20 are various. By selecting, various control methods are possible. A control method suitable for the state can be selected, and a control method suitable for the application can be selected.

  As a control method for maintaining the tilt of the rotor 30 at the target value, the tilt control of the rotor 30 may be performed by generating the same rotational force between the one-side stator 10 and the other-side stator 20. Further, for example, the tilt control about the Y axis is performed by the one side stator 10, and the tilt control about the X axis is performed by the other side stator 20, and the tilt control and the Y axis are centered on the X axis. It is also possible to control by dividing into tilt control centering on. In addition to tilt control, in order to improve control reliability, the control device is diagnosed, and if there is a risk of malfunction, the control of the malfunctioning person is stopped and only those who are operating correctly Thus, the tilt control of the rotor 30 can be performed.

  FIG. 6 is an explanatory diagram showing a specific structure when the principle of tilt control described in FIG. 4 and FIG. 5 is realized by the axial type magnetic levitation motor 100. In addition, illustration of the permanent magnet 33 provided in the other side stator 20 and the other side yoke of the rotor 30 is omitted. The rotor 30 has an impeller 31, and the impeller 31 is provided with one side yoke 312 and another side yoke 313 made of a magnetic material for forming a magnetic circuit. The one-side yoke 312 is provided with four permanent magnets 32 on the surface facing the one-side stator 10, and the four poles are formed by the permanent magnets 32. On the other hand, the one-side stator 10 has a stator core 15 having six salient poles, and a first winding 11 and a second winding 12 are formed by coils wound around each salient pole. The first winding 11 generates the same four-pole rotating magnetic field as the rotor 30, and generates a rotating torque with respect to the permanent magnet 32 of the rotor 30.

  On the other hand, the second winding 12 generates a magnetic field of P ± 2 with respect to the number P of magnetic poles provided in the rotor 30. In this embodiment, the stator magnetic pole 13 formed on the rotor 30 side of the stator iron core 15 by the second winding 12 is two poles. As described with reference to FIGS. 4 and 5, the stator magnetic pole 13 and the permanent magnet 32 A repulsive force 41 and an attractive force 42 are generated between the magnetic poles. The repulsive force 41 and the suction force 42 generate a rotational force 43 around the Y axis. By controlling the current value supplied to the second winding 12 and the phase with respect to the magnetic pole position of the rotor, the magnitude of the rotational force 43 and the direction of the rotational force can be freely controlled. It is possible to perform control to maintain the inclination of the rotor 30 at the target value by measuring with a sensor, calculating a control current for controlling the inclination of the rotor 30 to the target value, and supplying it to the second winding 12. It becomes.

  FIG. 7 is an explanatory diagram showing a state where M = P ± 2 is satisfied, where P is the number of poles of the permanent magnet of the rotor 30 and M is the number of poles formed by the stator winding. The relationship between the magnetic poles formed by the second winding 12 of the one-side stator 10 and the permanent magnet 32 is as follows: the second winding 22 of the other-side stator 20 and the permanent magnet provided on the opposing surface of the other-side stator 20 of the rotor 30. FIG. 7 shows only the magnetic pole relationship between the second winding 12 and the permanent magnet 32 as a representative.

  As in FIG. 4, the second winding 12 and the permanent magnet 32 are opposed to each other in the direction along the Z axis, but are magnetically formed by the permanent magnet 32 provided on the rotor 30 on the inner side. A magnetic pole formed by the second winding 12 is shown on the outer peripheral side. FIG. 7A shows a state in which the magnetic pole created by the permanent magnet 32 on the rotor 30 side is 2 poles and the magnetic pole created by the second winding 12 is 4 poles. 7B shows a state in which the magnetic pole created by the permanent magnet 32 on the rotor 30 side is 4 poles and the magnetic pole created by the second winding 12 is 6 poles, and FIG. 7C shows a magnetic pole created by the permanent magnet 32 on the rotor 30 side. FIG. 7 (D) shows that the permanent magnet 32 on the rotor 30 side has 4 poles and the second winding 12 has 2 poles. 7E shows a state in which the magnetic poles produced by the permanent magnets 32 on the rotor 30 side are 6 poles and the magnetic poles produced by the second winding 12 are 4 poles. FIG. A state in which the magnetic poles to be produced are 8 poles and the magnetic poles produced by the second winding 12 is 6 poles is shown.

  The embodiment described above with reference to FIGS. 1 to 6 corresponds to the state of FIG. 7D, and the magnetic poles produced by the permanent magnet of the rotor 30 are four poles, the second winding 12 or the second winding 22. There are two magnetic poles. The number of magnetic poles created by the first winding 11 and the first winding 21 is the same as the number of magnetic poles of the rotor 30 and is four poles.

  7A to 7C show the state of M = P + 2, and FIGS. 7D to 7F show the state of M = P-2. 7A to 7F all generate a repulsive force on the right side of the figure and a suction force on the left side of the figure. Therefore, as described above with reference to FIGS. 4 and 5, it is possible to control the inclination of the rotor 30 by controlling the current value and phase supplied to the second winding 12. Even when the number of poles other than those shown in FIGS. 7A to 7F is combined, when the number of magnetic poles of the rotor 30 is P and the number of magnetic poles generated by the second winding 12 is M, M = If the relationship of P ± 2 is satisfied, it is possible to perform control to correct the inclination of the rotor 30 and maintain the inclination of the rotor 30 at the target value as described above.

FIG. 8 and FIG. 9 show a method for generating a two-pole or four-pole rotating magnetic field by a coil wound around a 5.6 salient pole. When the winding 12 is wound, or when the first winding 21 or the second winding 22 is wound around the six salient poles formed on the stator core 25 to form a two-pole rotating magnetic pole, It is explanatory drawing which shows the state of the magnetic pole at that time. FIG. 8 shows the coil connection state, and FIG. 9 shows the magnetic pole state. In FIG. 8, the arrows indicate the winding directions of the coils wound around the salient poles formed on the stator iron core 15 or the stator iron core 25, respectively. Further, it is assumed that the coils C1 to C6 are sequentially arranged clockwise with respect to the salient poles of the stator iron core 15 or the stator iron core 25.

  In the U phase, a coil C1 and a coil C4 wound in the opposite direction to the coil C1 are connected in series. Similarly, in the V phase, a coil C2 and a coil C5 wound in the opposite direction to the coil C2 are connected in series. In the W phase, a coil C3 and a coil C6 wound in the opposite direction to the coil C3 are connected in series. When the coils are wound around the respective salient poles in this way, a rotating magnetic field having magnetic poles P1 and P2 can be generated as shown in FIG. In this example, the magnetic pole P1 is an N pole and the magnetic pole P2 is an S pole. The magnetic pole P1 and the magnetic pole P2 represent the magnetic poles of a rotating magnetic field that rotates at a rotational speed based on the frequency of the alternating current flowing through the U phase, V phase, and W phase in FIG. 8, and FIG. The state at a certain moment is shown as a still image.

  10 and 11 show that the first winding 11, the second winding 12, the first winding 21, or the second winding 22 is wound around six salient poles formed on the stator core 15 and the stator core 25. FIG. 10 is an explanatory diagram showing a coil connection state and a generated magnetic pole when four magnetic poles are generated, FIG. 10 shows a coil connection state, and FIG. 11 shows a generated magnetic pole state.

  In FIG. 10, the arrows indicate the winding direction of the coils wound around the salient poles of the stator iron core 15 and the stator iron core 25, and the coils C1 to C6 are sequentially arranged clockwise with respect to the salient poles. To do. In this case, the coils C1 to C6 are all in the same winding direction with respect to the salient poles. In the U phase, the coil C1 and the coil C4 are connected in series, in the V phase, the coil C2 and the coil C5 are connected in series, and in the W phase, the coil C3 and the coil C3 are connected in series. By connecting in this way, a rotating magnetic field is generated in which the magnetic pole P1 is an N pole, the magnetic pole P2 is an S pole, the magnetic pole P3 is an N pole, and the magnetic pole P4 is an S pole as shown in FIG. FIG. 11 shows a certain moment of the rotating magnetic pole, and the rotation speed of these magnetic poles is based on the frequency of the alternating current flowing through the U phase, V phase, and W phase shown in FIG.

6. Position control on the X-axis or Y-axis of the rotation center axis of the rotor 30 6.1 Generation of magnetic force in the X-axis direction of the rotor 30 Next, the number of poles of the permanent magnet of the rotor 30 is set to P, one side When the number of magnetic poles formed by the second winding 12 of the stator 10 or the second winding 22 of the other side stator 20 is M, X generated by the magnetic pole arrangement when the relationship of M = P ± 2 is satisfied. The magnetic force on the −Y axis will be described. First, in order to simplify the description, the magnetic force on the X axis will be described. FIG. 12 is an explanatory diagram showing the principle that a magnetic force in the X-axis direction is generated in the rotor 30 of the axial type magnetic levitation motor 100. As in FIG. 6, illustration of the permanent magnets 33 provided on the other side stator 20 and the other side yoke of the rotor 30 is omitted. Further, the structure of the rotor 30 and the one side stator 10 is the same as the structure described in FIG.

  As in FIG. 6, in this embodiment, the magnetic pole 13 generated by the second winding 12 of the one-side stator 10 has two poles, and the rotor 30 has four magnetic poles. Since a repulsive force 41 and an attractive force 42 are generated between the stator magnetic pole 13 and the magnetic pole of the permanent magnet 32 of the rotor 30, a rotational force 43 is generated in the clockwise direction around the Y axis. In FIG. 12, the N pole 32 of the magnetic field formed by the permanent magnet in the left half of the rotor 30 (X-axis negative direction) and the S pole of the stator magnetic pole 13 generate an attractive force 44, and the right half of the rotor 30 (X The repulsive force 45 is generated by the N pole 32 of the magnetic field produced by the permanent magnet in the positive axis direction and the N pole of the stator magnetic pole 13. The force component in the X-axis direction appears by the suction force 44 and the repulsive force 45. As a result, if the relationship of M = P ± 2 is established between the number P of the magnetic poles of the rotor 30 and the number M of the rotating magnetic fields generated by the stator winding, the attractive force 44 is applied in the positive direction of the X axis. The inventor found that the magnetic force 46 is generated based on the repulsive force 45.

  In order to perform stable rotation, the rotor 30 desirably rotates with the rotation center axis of the rotor 30 positioned on the center axis 500 determined based on the one-side stator 10 and the other-side stator 20. However, since there is no mechanical support mechanism, the rotation center axis that is the center axis of the rotor 30 may be displaced in the radial direction of the rotor 30, that is, the X axis direction or the Y axis direction while the rotor 30 is rotating. In the present embodiment, the radial direction for returning the rotation center axis of the rotor 30 to the position of the center axis 500 by measuring the difference between the rotation axis of the rotor 30 and the position of the center axis 500 in the X axis and Y axis directions with a sensor. Control of generating magnetic force, for example, magnetic force 46, is possible.

  That is, when controlling the magnitude of the rotational force 43 and the direction of the rotational force by controlling the current value of the control current supplied from the output unit 60 of the control unit 70 to the second winding 12 and the phase with respect to the magnetic pole position of the rotor. Similarly, the magnitude of the magnetic force 46 and the direction of the magnetic force 46 can be controlled. For example, when the rotation center axis of the rotor 30 is displaced in the positive direction of the X axis, it is necessary to generate a magnetic force 46 that acts on the rotor 30 in the negative direction of the X axis. The current value supplied to the wire 12 is set to a negative value, that is, the phase of the current value supplied to the second winding 12 is shifted by π, and the counterclockwise rotational force 43 is generated, in the negative direction of the X axis. The magnetic force 46 may be generated.

  Further, for example, when it is necessary to generate a magnetic force 46 that acts on the rotor 30 in the positive direction of the Y axis in order to correct the deviation of the rotation center axis of the rotor 30, the X axis of FIG. If the control current supplied to the second winding 12 generating the magnetic force 46 in the positive direction is supplied to the second winding 12 with a control current further shifted by π / 2 with respect to the magnetic pole of the rotor 30. good. Thus, by changing the phase of the control current to the second winding 12 with respect to the magnetic pole of the rotor 30 and the magnitude of the control current, the direction of the magnetic force 46 acting on the rotor 30 in the XY coordinate system Its size can be controlled.

  The example in which the number of magnetic poles P of the rotor 30 is 4 and the number of magnetic poles M of the rotating magnetic field generated by the second winding 12 is 2 has been described with reference to FIG. However, the above description is not limited to the relationship of the magnetic poles in FIG. As in FIG. 7, FIG. 13 shows the state of the magnetic poles when the number of poles of the permanent magnet of the rotor 30 is P and the number of poles M formed by the stator winding satisfies the relationship of M = P ± 2 and the generated magnetism. It is explanatory drawing which shows direction of force. As in FIG. 7, only the relationship between the magnetic poles of the second winding 12 and the permanent magnet 32 is shown in FIG.

  FIG. 13 shows the X-axis direction force generated when the number of poles of the permanent magnet of the rotor 30 is P and the number of poles formed by the stator winding is M, indicating a state where M = P ± 2. It is explanatory drawing. Since the magnetic poles created by the permanent magnet 32 on the rotor 30 side in FIGS. 13A to 13F and the magnetic poles created by the second winding 12 are the same as the magnetic poles shown in FIGS. The description is omitted. The embodiment described with reference to FIG. 12 corresponds to the state of FIG. The relationship between the number of magnetic poles P of the rotor 30 shown in FIGS. 13A to 13C and the number of magnetic poles M of the rotating magnetic field generated by the second winding 12 is a relationship of M = P + 2. At this time, a magnetic force is generated in the negative direction of the X axis. On the other hand, the relationship between the number of magnetic poles P of the rotor 30 and the number of magnetic poles M of the rotating magnetic field generated by the second winding 12 shown in FIGS. 13D to 13F is a relationship of M = P−2. At this time, a magnetic force is generated in the positive direction of the X axis as described with reference to FIG.

6.2 Control of Inclination of Rotor 30 and Control of Rotation Center Axis Position of Rotor 30 In FIGS. 6 and 12, the rotational force generated in the one-side stator 10 and the rotor 30 is shown for the sake of simplicity of explanation. 43 and the magnetic force 46 have been described. Since the other-side stator 20 having the same structure is disposed so as to face the one-side stator 10 in the Z-axis direction as described with reference to FIG. The control of the rotor 30 by these two stators will be described. In this embodiment, the rotational force for controlling the inclination of the rotor 30 and the magnetic force for correcting the deviation of the rotation center axis of the rotor 30 are generated. As an example, the case where the number of poles of the permanent magnet of the rotor 30 is 4 and the number of poles of the magnetic field created by the stator winding is 2 will be described so that the number of poles M created by the line satisfies the relationship of M = P ± 2. .

  14A and 14B show the case where the tilt around the Y axis of the rotor 30 and the position of the rotation center axis in the X axis direction are controlled by the one side stator 10 and the other side stator 20. It is explanatory drawing which shows a control principle. Here, it is assumed that the current value supplied to the second winding 12 of the one-side stator 10 and the second winding 22 of the other-side stator 20 is the same, and the rotational force 43 and the rotation generated by the two stators. The magnitudes of the force 48, the magnetic force 46, and the magnetic force 47 are the same. The one side stator 10 and the other side stator 20 are the same (the winding method and direction are the same and the top and bottom are turned over), and the second winding of the one side stator 10 is the same. 12 and the second winding 22 of the other side stator 20, when the same current is supplied in the same direction, magnetic poles are generated as indicated by 13 and 23 in FIG.

A permanent magnet having four poles is provided on the surface 32 facing the one side stator 10 of the rotor 30 and the surface 33 facing the other side stator 20. In the embodiment shown in FIG. 14, the permanent magnets are arranged so as to have the same magnetic pole arrangement on both side surfaces of the rotor. As shown in FIGS. 14A and 14B, the arrangement of the rotor magnets is the same magnetic pole arrangement on both sides of the surface 32 and the surface 33, that is, the magnetic pole of which the other side 33 of the N pole of the surface 32 is the N pole. The arrangement state will be described below, but is not limited thereto. As described with reference to FIGS. 12 and 4 to 6, the rotation generated to correct the inclination by controlling the phase of the current supplied to the second winding 12 and the stator magnetic pole 13 in relation to the magnetic pole of the rotor. Since the direction of the force and the direction of the magnetic force 46 generated to correct the position of the rotation center axis of the rotor 30 can be freely controlled on the XY coordinates, the permanent direction facing the one-side stator 10 of the rotor 30 is permanent. The magnetic pole arrangement of the magnet 32 and the magnetic pole arrangement of the permanent magnet 33 facing the other side stator 20 may be shifted. For example, the permanent magnet 33 corresponding to the north pole of the permanent magnet 32 may be shifted by 90 degrees so as to be the south pole. In the following description, for ease of understanding,
It is assumed that the permanent magnets 32 and the permanent magnets 33 arranged on both side surfaces of the rotor 30 are the same arrangement and the magnetic pole arrangement is the same.

  FIG. 14A shows a case where a control current in the same direction is supplied to the second winding 12 of the one-side stator 10 and the second winding 22 of the other-side stator 20, respectively, and rotation about the Y axis is performed. It is a figure which shows the relationship between the rotational force and magnetic force at the time of making it generate | occur | produce the force 43 and the rotational force 48. FIG. The rotating magnetic field generated by the second winding 12 of the one-side stator 10 and the second winding 22 of the other-side stator 20 is always in phase with the rotor 30. As described with reference to FIGS. 6 and 12, the rotational force 43 in the clockwise direction around the Y axis is generated by the magnetic field 13 generated by the one-side stator 10 and the magnetic field generated by the permanent magnet 32 of the rotor 30. At the same time, a magnetic force 46 is generated in the positive direction of the X axis.

  A control current having the same magnitude and the same phase as that of the one-side stator 10 is also supplied to the other-side stator 20. Due to the magnetic field 23 generated by the other side stator 20 and the magnetic field generated by the permanent magnet 33 of the rotor 30, a clockwise rotational force 48 is generated around the Y axis, and at the same time, a magnetic force 47 is generated in the negative direction of the X axis. At this time, the rotational forces 43 and 48 on both sides of the rotor 30 are generated in the same clockwise direction, so that they are strengthened to each other, and the magnetic force 46 and the magnetic force 47 are generated in opposite directions, so that they cancel each other.

  Therefore, when control currents in the same direction are supplied to the one-side stator 10 and the other-side stator 20, only the rotational forces 43 and 48 can be generated in the rotor 30. With this force, the rotor 30 can be tilted clockwise around the Y axis. When the deviation of the rotation center axis of the rotor 30 is small and only the inclination is corrected, the control current in the same direction is supplied to the second winding 12 and the second winding 22 in this way so that only the rotational force is supplied. Can be controlled to control only the inclination. Further, by changing the phase of the rotating magnetic field created by the second winding 12 and the second winding 22 with respect to the rotor, the rotational force 43 and the rotational force 48 are similarly canceled while canceling out the magnetic force 46 and the magnetic force 47. It is possible to rotate the rotation axis in an arbitrary direction on the XY coordinates. For example, when the phase difference between the rotating magnetic field and the rotor is π, the rotating force 43 and the rotating force 48 are generated around the X axis. In addition, the direction of the magnetic force 46 and the magnetic force 47 is reversed by reversing the direction of the control current supplied to the second winding 12 and the second winding 22 in the negative direction in the state shown in FIG. The rotational direction of the rotational force 43 and the rotational force 48 can be changed from the clockwise direction to the counterclockwise direction.

  FIG. 14B shows a case where a positive current is supplied to the second winding 12 of the one-side stator 10 and a negative current is supplied to the second winding 22 of the other-side stator 20. FIG. 6 is a diagram showing the relationship between the rotational force generated in the rotor 30 and the magnetic force. As described above, a clockwise rotational force 43 around the Y axis is generated by the magnetic field 13 generated by the second winding 12 of the one-side stator 10 and the magnetic field generated by the permanent magnet 32 of the rotor 30, and at the same time X A magnetic force 46 is generated in the positive direction of the shaft.

  The other side stator 20 is supplied with a control current in the negative direction. The magnetic field 23 generated by the second winding 22 of the other side stator 20 and the magnetic field generated by the permanent magnet 33 of the rotor 30 generate a counterclockwise rotational force 48 around the Y axis, and simultaneously in the positive direction of the X axis. A magnetic force 47 is generated. At this time, the rotational force 43 and the rotational force 48 generated on both side surfaces of the rotor 30 are generated in opposite directions and cancel each other, and the magnetic forces 46 and 47 are generated in the same direction and strengthen each other.

  Therefore, by reversing the direction of the control current supplied to the second winding 12 of the one-side stator 10 and the control current supplied to the second winding 22 of the other-side stator 20, the rotor 30 Only the magnetic forces 46 and 47 can be generated. When the rotation center axis of the rotor 30 is deviated in the negative direction of the X axis from the center axis shown in FIG. 12 and there is no deviation of the inclination around the Y axis, the rotation force 43 and the rotation force 48 cancel each other. The magnetic force 46 and the magnetic force 47 for moving only the rotation center axis of the rotor 30 in the positive direction of the X axis are generated, and only the position control of the rotation center axis of the rotor 30 that is radial control is performed. Is possible. FIG. 14B shows a case where a control current in the positive direction is supplied to the second winding 12 of the one-side stator 10 and a control current in the negative direction is supplied to the second winding 22 of the other-side stator 20. . In this state, when control currents in opposite directions are applied to the second winding 12 and the second winding 22, respectively, the rotational force 43 and the rotational force 48 are maintained in a mutually cancelled state (the rotational force 43 and the rotational force). The direction of the magnetic force 46 and the magnetic force 47 can be changed to the opposite direction.

  In this way, in the configuration of FIG. 14B, by changing the direction of the control current supplied to the second winding 12 and the second winding 22, the rotational force 43 and the rotational force 48 cancel each other, The magnetic force 46 and the magnetic force 47 can be added, and the position of the rotation center axis of the rotor 30 can be moved on the X axis without changing the inclination of the rotor 30. Further, the phase of the rotating magnetic field generated by the second winding 12 and the second winding 22 with respect to the magnetic poles of the rotor 30 is maintained while maintaining the current direction of the control current supplied to the second winding 12 and the second winding 22. By changing, the position of the rotation center axis of the rotor 30 can be moved on the XY coordinates without changing the inclination of the rotor 30. In this way, it is possible to control to maintain the position of the rotation center axis of the rotor 30 at a predetermined position on the XY coordinates.

Further, by shifting the arrangement of the permanent magnets 32 and 33 on both sides of the rotor described above in the rotational direction, for example, the permanent magnet 33 on the other side corresponding to the N pole of the permanent magnet 32 on the one side becomes the S pole. Thus, when the magnetic poles of the permanent magnet 32 and the permanent magnet 33 are arranged 90 degrees apart from each other in the rotational direction, the direction of the rotational force generated on the upper and lower surfaces of the rotor 30 shown in FIGS. Even if the direction of the magnetic force is reversed and the control current in the same direction, that is, the same direction, is supplied to the one side stator 10 and the other side stator 20, the effect described in FIG. 14B can be obtained. On the other hand, in this case, if currents in opposite directions are supplied to the one side stator 10 and the other side stator 20, the effect described with reference to FIG.
As described above, the direction of the control current supplied to the second winding 12 of the one-side stator 10 and the second winding 22 of the other-side stator 20, the second winding 12 with respect to the magnetic poles of the rotor 30, By adjusting the phase difference of the rotating magnetic field generated by the second winding 22 with respect to the rotor, both rotational force and magnetic force are generated, or only one of them is generated, and the direction of these forces is expressed in the XY coordinates. It is possible to control freely above. The magnitude of the force can be controlled by changing the magnitude of the control current supplied to the second winding 12 and the second winding 22.

7. Calculation processing of control unit 70 7.1 Position of rotor 30 in Z-axis direction and rotation speed control of rotor 30 Next, control for maintaining the position of rotor 30 in the Z-axis direction at a predetermined position, and rotor The control of the rotation speed of 30 will be described. As described above, the first winding 11 of the one-side stator 10 and the first winding 21 of the other-side stator 20 generate a rotating magnetic field and apply a rotational force (torque) to the rotor 30 including the permanent magnet 32. ) And is used for control to maintain the rotor 30 in a predetermined position on the Z axis.

The control current of the three-phase AC is calculated by calculating the control amount as a two-phase DC current I _d , I _q consisting of a q-axis (torque) component current I _q and a d-axis (field) component current I _d. The control amount thus obtained can be converted into a three-phase alternating current by a two-phase three-phase conversion unit 109 described later, and a three-phase control current value can be obtained.

  The control for maintaining the rotor 30 at a predetermined position on the Z-axis increases or decreases the magnetic flux density between the magnetic field generated by the first winding 11 disposed opposite to the Z-axis and the permanent magnet 32 provided on the rotor 30. By adjusting the attractive force, the magnetic force density between the permanent magnet 33 provided on the rotor 30 and the magnetic field generated by the first winding 21 disposed opposite to the Z-axis is increased or decreased. This is done by adjusting. The magnetic field that increases or decreases the attractive force with respect to the permanent magnet 32 or the permanent magnet 33 can be controlled by the d-axis (field) component of the control current supplied to the first winding 11 or the first winding 21.

On the other hand, the control of the rotational speed of the rotor 30 is based on the difference from the target rotational speed, and the magnetic field generated by the first winding 11 and the first winding 21 and the rotation generated by the permanent magnet 32 and the permanent magnet 33 provided on the rotor 30. This is done by controlling the magnitude of the torque. The magnitude of the rotational torque can be controlled by the current I _q of the q-axis (torque) component of the control current supplied to the first winding 11 and the first winding 21.

The control of the attraction force in the Z-axis direction for maintaining the rotor 30 at a predetermined position on the Z-axis and the rotational torque for maintaining the rotational speed of the rotor 30 at the target speed are based on the theory of vector control. The command value of the current is calculated, and based on the calculated d-axis (field) component and q-axis (torque) component values, the command current value of the three-phase alternating current is obtained, A control current to be supplied to one winding 21 is created. The attraction force F and the rotational torque (rotational force) T in the Z-axis direction are expressed by the following equations using the current I _q of the d-axis (field) component and the current I _q of the q-axis (torque) component. Can be calculated.

ここで、ｋ_Ｆとｋ_Ｔは比例定数である。数式（数１）を用いることにより、ロータ３０のＺ軸方向の位置制御のためのＺ軸方向の増減分吸引力を発生する制御電流Ｉ_ｄを演算することができる。さらにロータ３０の回転速度の制御に必要な回転トルクを発生するための制御電流Ｉ_ｑを演算により決定することができる。決定した電流値Ｉ_ｄおよびＩ_ｑを後述する二相三相変換部１０９で座標変換することにより、三相交流電流値に変換し、変換された三相交流電流値に基づいて、出力部６０により三相交流電流を発生して、第１巻線１１を構成するコイルへ交流電流値Ｉ_Ｕ、Ｉ_Ｖ、Ｉ_Ｗに基づく制御電流を供給する。

Here, _{k F} and _{k T} is a proportionality constant. By using the equation (Equation 1), it is possible to calculate the control current I _d for generating the increment or decrement the suction force of the Z-axis direction for the position control of the Z-axis direction of the rotor 30. Furthermore, the control current _Iq for generating the rotational torque necessary for controlling the rotational speed of the rotor 30 can be determined by calculation. The determined current values I _d and I _q are converted into coordinates by a two-phase / three-phase conversion unit 109 to be described later, thereby converting to a three-phase AC current value. Based on the converted three-phase AC current value, the output unit 60 To generate a three-phase alternating current, and supply a control current based on the alternating current values I _U , I _V , and I _W to the coils constituting the first winding 11.

  FIG. 15 is a control block diagram for controlling the position of the rotor 30 in the Z-axis direction and further controlling the rotational speed of the rotor 30. The control unit of the rotor 30 includes a measurement unit 40, a calculation processing unit 50 that performs calculation at high speed, and an output unit 60 that generates a control current based on the calculation result.

  For the control of the position of the rotor 30 in the Z-axis direction and the rotational speed control of the rotor 30, displacement sensors 101, 102, 103 such as three eddy current displacement sensors, one side stator 10, and the other side stator 30 are used. , A rotation angle sensor 104 such as a Hall IC, an A / D converter that converts the output of each displacement sensor into a digital value, and a calculation unit that calculates the rotation angle and speed are used. The position of the rotor 30 in the Z-axis direction is measured by the three displacement sensors 101, 102, and 103, and converted into digital values by the A / D converter. The rotational speed of the rotor 30 is measured by a sensor 104 using a Hall IC or the like. The rotational speed of the rotor 30 measured by the sensor 104 is used for controlling the rotational speed of the rotor 30 described later.

  The arithmetic processing unit 50 performs arithmetic operations described below. In this specification, not only algebraic calculation but also a calculation including a method of retrieving a result calculated in advance or preset based on input data and obtaining the result is defined. The A / D converter described in the measurement unit 40 may perform the A / D conversion function built in the microprocessor at an appropriate timing in the arithmetic processing. The measurement unit 40, the arithmetic processing unit 50, and the output unit 50 may be realized using a computer system such as a one-chip microcomputer or a DSP. In this embodiment, each functional block constituting these is realized by the one-chip microcomputer and the processing program.

The arithmetic processing unit 50 takes in the measured values Z1, Z2, and Z3 in the Z-axis direction measured by the sensors 101 to 103 converted into digital values, calculates the average value of the measured values Z1, Z2, and Z3, The position Z of the rotor 30 in the Z-axis direction is calculated. A deviation from the target position of the rotor 30 in the Z-axis direction is calculated, and a necessary suction force F in the Z-axis direction is calculated by the PID control unit 105 based on the deviation. From the calculated Z-axis direction attractive force F, the current value _Id is calculated by the calculation unit 106 using (Equation 1).

Three-phase alternating current I _U by converting the current value I _q calculated by the calculation described below with the calculated current value I _d by the arithmetic unit 106 in a two-phase three-phase conversion unit _109, I _V, obtaining the I _W . The three-phase AC currents based on these three-phase AC current values I _U , I _V , and I _W are generated by the D / A converters 201 to 203 included in the output unit 60, and the first stator 10 of the one-side stator 10 is passed through a linear amplifier or the like. Supply to winding 11.

Next, calculation related to control of the rotational torque of the rotor 30 will be described. By detecting the permanent magnets 32 and 33 of the rotor 30 using the sensor 104 made of a Hall IC, the rotation angle indicating the magnetic pole position of the rotor and the rotation speed of the rotor 30 are measured. Then, the output signal of the sensor 104 is taken into the arithmetic processing unit 50 via the rotation speed calculation unit. Similar to the calculation of the Z-axis direction suction force F described above, the difference between the rotational speed value of the target value set in advance and the measured rotational speed value for feedback control in the PID control unit 107 of the arithmetic processing unit 50 is calculated. Then, the rotational force T necessary to reach the target rotational speed value is calculated. Then, the current value I _q is calculated from the rotational force T in the calculation unit 108 using (Equation 1).

Current values minus I _d and I _q described later are converted into three-phase alternating current values I _U , I _V , and I _W by the coordinate conversion unit 110. Then, the D / A converter of the output unit 60 converts the calculated digital signals of the three-phase alternating current values I _U , I _V , and I _W into analog signals, and passes through the linear amplifier and the like on the other side stator 20. One winding 21 is supplied.

  The first winding 11 and the first winding 21 control the position of the rotor 30 on the Z axis. In this case, the direction in which the force acting on the rotor 30 acts is opposite between the first winding 11 and the first winding 21. For this reason, it is necessary to reverse the control amounts. That is, when the rotor 30 is moved in the direction of the one-side stator 10, the suction force between the first winding 11 and the rotor 30 is increased, and the suction force between the first winding 21 and the rotor 30 is increased. It must be reduced. Therefore, the two-phase three-phase conversion is performed by setting the three-phase alternating current value supplied to the first winding 21 as minus Id representing the force in the reverse direction of the calculated value Id for the first winding 11 calculated by the calculation unit 106. To the unit 110. Based on the three-phase AC current value converted by the two-phase / three-phase converter 109, a three-phase AC current is generated by the output unit 60, and a control current is supplied to the coil constituting the first winding 11 of the one-side stator 10. As a linear amplifier. Further, based on the three-phase AC current value converted by the two-phase / three-phase converter 110, a three-phase AC current is generated by the output unit 60, and the coil constituting the first winding 21 of the other side stator 20 is generated. A control current is supplied through a linear amplifier or the like. By doing so, based on the control of the position of the rotor 30 on the Z axis and the control of the rotational torque acting on the rotor 30 by the rotating magnetic field generated based on the first winding 11 and the first winding 21. The rotational speed of the rotor 30 can be controlled.

  In the calculation block diagram shown in FIG. 15, a three-phase AC control current is supplied to the first winding 11 of the one-side stator 10 and the first winding 21 of the other-side stator 20 in order to rotate the rotor. doing. Although a rotating magnetic field can be generated efficiently by using a three-phase alternating current, it is not necessarily limited to a three-phase alternating current to generate a rotating magnetic field. As will be described later, the number of poles of the rotating magnetic field to be generated is determined by the relationship with the number of magnetic poles of the rotor. For example, a rotating magnetic field for rotating the rotor can be generated with a two-phase alternating current, or a rotating magnetic field can be generated using a six-phase alternating current. Accordingly, when a three-phase alternating current is used as the control current supplied to the first winding 11 and the first winding 21, a rotating magnetic field can be generated efficiently. However, the number of poles of the generated rotating magnetic field and the first Depending on the number of coils constituting the winding 11 and the first winding 21, it is also possible to supply alternating current of other phases as a control current.

7.2 Rotor Inclination Control and Position of Rotation Center Axis of Rotor 30 on XY Coordinate As described above, the inclination control of rotor 30 and the control of the radial position are performed by the second side stator 10. This is done by adjusting the direction of the control current supplied to the winding 12 and the second winding 22 of the other side stator 20, the phase of the rotating magnetic field, and the peak value. The rotational force t and the radial magnetic force f that control the tilt generated by the one-side stator 10 and the other-side stator 20 are the current supplied to the second winding 12 of the one-side stator 10 I. _Assuming that the _top is I and the current supplied to the second winding 22 of the other side stator 20 is I _bottom , it is expressed by the following equation (Equation 2).

ここで、ｋ_Ｒとｋ_Ｔは比例定数である。数式（数２）を用いることにより、ロータの傾き制御および径方向位置制御に必要な径方向磁気力すなわちＸあるいはＹ座標方向の成分を有する磁気力、およびＸ軸あるいはＹ軸を中心とする回転成分を有する回転力に従ってＩ_topおよびＩ_bottomを演算により決定する。決定した電流値Ｉ_topおよびＩ_bottomを座標変換することにより、例えば三相交流へと変換しコイルへ交流の電流値Ｉ_Ｕ、Ｉ_Ｖ、Ｉ_Ｗを算出し、これに基づく交流電流を第２巻線１２と２２に供給することにより磁界を発生させる。

Here, _{k R} and _{k T} is a proportionality constant. By using the mathematical formula (Equation 2), radial magnetic force necessary for rotor tilt control and radial position control, that is, magnetic force having a component in the X or Y coordinate direction, and rotation around the X or Y axis. I _top and I _bottom are determined by calculation according to the rotational force having components. By converting the coordinates of the determined current values I _top and I _bottom , for example, the current values I _U , I _V , and I _W are calculated by converting the current values I _top and I _bottom into a three-phase alternating current. A magnetic field is generated by supplying the windings 12 and 22.

  FIG. 16 is a control block diagram for controlling the inclination and radial position of the rotor 30. 16 includes a control block diagram for performing the tilt around the X axis and the Y-axis direction position control, and the one including the calculator 209 in FIG. 16 includes the tilt around the Y axis and the X axis. It is a control block diagram for performing axial position control. The control unit of the rotor 30 is the same as that described in the Z-axis direction position and rotation speed control of the rotor with reference to FIG. 15. From the measurement unit 40, the calculation processing unit 50 that performs high-speed calculation, and the output unit 60, Composed.

  The configuration of the measurement unit 40 is the same as that described with reference to FIG. Displacement sensors 204 and 205 arranged on the X-axis and Y-axis, respectively, and the respective A / D converters are used.

The arithmetic processing unit 50 calculates the current values I _top and I _bottom using the PID control units 207, 208, 305, and 306 that calculate the required radial magnetic force f and the tilt restoring rotational force t and (Equation 2). Arithmetic units 209 and 307, and arithmetic units 300 and 308 that convert the current values I _top and I _bottom into three-phase alternating currents I _U , I _V , and I _W by converting the coordinates.

The output unit 60 includes D / A converters 301 to 303 and 309 to 311 that convert the calculated digital signals of the three-phase alternating currents I _U , I _V , and I _W into analog signals, and a one-side statuser. It comprises a linear amplifier for supplying current to the 10 second windings 12 and the second winding 22 of the other side stator 20.

Next, the Y-axis direction position and tilt rotation control of the rotor 30 shown in FIG. 16 will be specifically described. The inclination θ _x around the X axis of the rotor 30 is detected by the displacement sensors 101, 102, and 103. The detected analog signal is converted into a digital signal through an A / D converter, and values Z1, Z2, and Z3 in the Z-axis direction are output. From these values, the inclination θ _x around the X-axis is calculated by θ _x. Calculated by the unit 206.

Then, by the feedback control in the PID control unit 207 of the arithmetic processing unit 50, the difference between the inclination θ _x around the X axis of the preset target value and the calculated inclination θ _x is calculated and becomes the target value θ _x . The rotational force _tθx required for this is calculated.

Further, the position Y of the rotor 30 in the Y-axis direction is measured using the displacement sensor 205 disposed on the Y-axis on the outer periphery of the rotor 30. Then, the position Y is taken into the arithmetic processing unit 50 via the A / D converter. The difference between the preset target value Y and the measured Y is calculated by feedback control in the PID control unit 208 of the arithmetic processing unit 50, and the radial magnetic force f _y required to become the target value Y is obtained. Calculated.

The inclination θ _y around the Y axis of the rotor 30 is detected by the displacement sensors 101, 102, and 103. The detected analog signal is converted into a digital signal through an A / D converter, and values Z1, Z2, and Z3 in the Z-axis direction are output. From these values, the inclination θ _y around the Y-axis is calculated by θ _y. Calculated by the unit 304.

Then, by the feedback control in the PID control unit 305 of the arithmetic processing unit 50, the difference between the inclination θ _y around the X axis of the preset target value and the calculated inclination θ _y is calculated and becomes the target value θ _y . Therefore, the rotational force _tθy necessary for this is calculated.

Further, the position X in the X-axis direction of the rotor 30 is measured using the displacement sensor 204 disposed on the X-axis on the outer periphery of the rotor 30. Then, the position X is taken into the arithmetic processing unit 50 via the A / D converter. By the feedback control in the PID controller 306 of the arithmetic processing unit 50, it calculates the difference between the X that has been determined X of preset target value, the magnetic force f _x in the radial direction needed to become X target value Calculated.

Then, the computing unit 209 calculates current values I _{top θX} and I _{bottom θX} from the rotational force t _θx and the radial magnetic force f _y using ( _Equation 2). Next, the computing unit 307 calculates current values I _topθY and I _bottomθY from the rotational force t _θy and the radial magnetic force f _x using ( _Equation 2). Next, the arithmetic units 300 and 308 obtain current values I _top and I _bottom to be passed through the one-side stator 10 and the other-side stator 20, respectively, and three-phase AC currents I _U , I _V , I _W are obtained by coordinate conversion. The D / A converters 301 to 303 and 309 to 311 of the output unit 60 convert the calculated digital signals of the three-phase alternating currents I _U , I _V , and I _W into analog signals, and Current is supplied to the second winding 12 of the stator 10 and the second winding 22 of the other side stator 20 through a linear amplifier.

  As described above, the rotation of the rotor 30 in the X and Y axis directions and the tilt rotation control around the X axis and the Y axis are performed.

8). Regarding Other Embodiments In the above-described embodiments, the one-side stator 10 or the other-side stator 20 includes the first winding 11 and the second winding 12 or the first winding 21 and the second winding 22, and the stator A magnetic field in which the magnetic fields generated by the first winding 11 and the second winding 12 are added appears on the iron core 15 and acts on the permanent magnet of the rotor 30. On the other hand, the magnetic fields generated by the first winding 21 and the second winding 22 are added by the stator core 25 and act on the permanent magnet of the rotor 30 as the added magnetic field. Functions of the first winding 11 and the second winding 12 instead of the first winding 11 and the second winding 12 or the first winding 21 and the second winding 22 of the one-side stator 10 or the other-side stator 20. In order to provide the functions of the first winding 21 and the second winding 22, at least one winding can be provided to the one-side stator 10 and the other-side stator 20, respectively. In this case, the control currents supplied to the first winding 11 and the second winding 12 are added, and the added current is supplied as control current to at least one winding provided to the one-side stator 10. To do. Further, the control currents supplied from the first winding 21 and the second winding 22 are added, and the added current is supplied as control current to at least one winding provided to the other stator 20.

  DESCRIPTION OF SYMBOLS 10 ... One side stator, 11 ... One side stator 1st winding, 12 ... One side stator second winding, 13 ... Magnetic field which 1 side stator 2nd winding produces, 15 ... Stator Iron core, 20 ... other side stator, 21 ... other side stator first winding, 22 ... other side stator second winding, 23 ... magnetic field generated by the other side stator second winding, 25 ... stator iron core, 30 ... rotor, 31 ... impeller, 32, 33 ... permanent magnet, 40 ... measuring part, 41, 45 ... repulsive force, 42, 44 ... attractive force, 43, 48 ... rotational force around Y axis, 46 , 47 ... Magnetic force in the X-axis direction, 50 ... Arithmetic processing unit, 60 ... Output unit, 70 ... Control unit, 100 ... Axial magnetic levitation motor, 101, 102, 103, 104, 204, 205 ... Sensor, 105, 107 , 206, 208 ... PID control unit, 106, 108, 207 ... calculation unit, 109, 110, 209 ... two-phase / three-phase conversion unit 112 ... first coil, 122 ... second coil, 201～206,301～303 ... output terminal, 221 ... first coil, 222 ... second coil, 312 and 313 ... York, 314 ... hole 500 ... center line.

Claims (8)

A rotor that rotates about a rotation center axis provided in the Z-axis direction of an orthogonal coordinate system including an X-axis, a Y-axis, and a Z-axis;
A one-side stator that is disposed at one side of the rotor along the Z-axis and includes at least one winding composed of a plurality of coils;
An other side stator provided with at least one winding composed of a plurality of coils, spaced apart from the other side of the rotor along the Z axis;
A control unit for supplying a control current to the winding of the one-side stator and the winding of the other-side stator,
Each of the one-side stator and the other-side stator further includes a stator core having a plurality of salient poles, and the coils constituting the winding are wound around the salient poles of the stator cores,
A plurality of permanent magnets for forming magnetic poles of the rotor are disposed on a surface facing the one-side stator of the rotor and a surface facing the other-side stator,
The at least one winding provided in each of the one-side stator and the other-side stator controls rotational torque generated from the control unit to the rotor, and the X-axis of the rotation center axis of the rotor and Supplying the control current for performing control to maintain the position of the coordinate by the Y axis at a predetermined position;
Axial type magnetic levitation motor. The axial type magnetic levitation motor according to claim 1,
The control unit calculates a rotation torque control value for controlling the rotation torque generated in the rotor, and a rotation center axis position control value for controlling the coordinate position of the rotor by the X axis and the Y axis. Generating the control current based on the rotation torque control value and the rotation center axis position control value and supplying the control current to at least one of the windings of the one-side stator and the other-side stator, respectively. A feature of the axial type magnetic levitation motor. The axial type magnetic levitation motor according to claim 2,
Based on the calculated rotational torque control value, the number of poles M for generating a rotating magnetic field that each of the one-side stator and the other-side stator has is the same as the number of poles P created by the magnet of the rotor,
Based on the calculated rotation center axis position control value, the number of poles M for generating the rotating magnetic field of each of the one-side stator and the other-side stator is M = P ± with respect to the pole number P created by the magnet of the rotor. An axial magnetic levitation motor characterized by having a relationship of two. The axial type magnetic levitation motor according to claim 1,
The one-side stator and the other-side stator each include at least a first winding and a second winding,
A rotation torque control value for controlling a rotation torque generated in the rotor, and a rotation center axis position control value for controlling a position of a coordinate of the rotation center axis of the rotor by the X axis and the Y axis; Operate,
The control unit supplies the control current to the first windings of the one-side stator and the other-side stator based on the calculated rotation torque control value, and further calculates the rotation center axis position control. Supplying the control current to the second windings of the one-side stator and the other-side stator based on values,
When the number of poles of the rotating magnetic field created by each of the second windings is M and the number of poles created by the magnet of the rotor is P, the relationship M = P ± 2 is established.
Axial type magnetic levitation motor. The axial type magnetic levitation motor according to claim 2,
The control unit has an arithmetic processing unit and an output unit,
The arithmetic processing unit, based on the measured position of the rotation center axis of the rotor and the measured inclination of the rotor, the coordinate position of the rotation center axis of the rotor by the X axis and the Y axis, and the rotor Rotation center axis position control value and tilt control value for controlling the tilt of
The output unit supplies the control current to the windings of the one-side stator and the other-side stator, respectively, based on the calculated rotation center axis position control value and tilt control value. Axial maglev motor. The axial type magnetic levitation motor according to claim 4,
The control unit has an arithmetic processing unit and an output unit,
The arithmetic processing unit, based on the measured position of the rotation center axis of the rotor and the measured inclination of the rotor, the coordinate position of the rotation center axis of the rotor by the X axis and the Y axis, and the rotor Rotation center axis position control value and tilt control value for controlling the tilt of
Based on the calculated rotation center axis position control value and inclination control value, the output unit includes a position of the rotation center axis of the rotor and the second winding of the one side stator and the other side stator, respectively. An axial type magnetic levitation motor, characterized in that the control current for controlling the inclination of the rotor is supplied. An axial type magnetic levitation motor according to claim 5 or 6,
The arithmetic processing unit, based on the measured value of the inclination of the rotor about the X axis and the measured value of the position of the rotation center axis in the Y-axis direction, the position of the rotation center axis of the rotor and the inclination of the rotor An axial type magnetic levitation motor characterized by calculating the rotation center axis position control value and the tilt control value of the one-side stator and the other-side stator for controlling the rotation, respectively. An axial type magnetic levitation motor according to claim 5 or 6,
The arithmetic processing unit determines the position of the rotation center axis of the rotor and the inclination of the rotor based on the measurement value of the inclination of the rotor around the Y axis and the measurement value of the position of the rotation center axis in the X axis direction. An axial type magnetic levitation motor characterized by calculating the rotation center axis position control value and the tilt control value of the one-side stator and the other-side stator for controlling the rotation, respectively.

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