JP2002325476A - Motor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor device, which has high efficiency, is small in size, is low in manufacturing cost, and can control the shaft position of its rotor. SOLUTION: Stator windings 4A-4I are divided into three sets of stator winding groups, which are respectively star-connected and have respective independent neutrals N1, N2, and N3. By controlling voltages or currents of the neutrals, an unbalance flux distribution in the stator is produced, to generate a force applied in radial directions of a rotor. Since the stator windings 4A-4I have both functions for generating a rotating force and position control and a stator 3 is constructed by a concentrated winding method, using divided cores, the construction can be made simple and the space factor of the winding can be made high, a motor small in size high in efficiency and low in cost, capable of controlling the position of its shaft can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor device having a stator including a split stator core and a concentrated winding provided on the split stator core.

[0002]

2. Description of the Related Art In recent years, further miniaturization and higher output have been demanded for motors. In response to such demands, in order to reduce the mechanical loss due to friction in the rotor bearings and increase the efficiency, the gap magnetic flux is controlled to create an imbalance state to generate a radial force and control the rotor shaft position. Motors have been proposed. In such a motor, the position of the shaft can be controlled by adjusting the current flowing through the winding, and a bearing mechanism for mechanically holding the shaft can be eliminated. As a result, it is possible not only to improve the efficiency by eliminating the loss due to the friction of the bearing, but also to eliminate the problem of lubrication and abrasion, thereby realizing a motor that can withstand use under high vacuum or ultra high speed, for example. be able to.

An example of such a motor is a bearingless motor. In this bearingless motor, a position control winding for controlling the shaft position of the rotor is provided in addition to the armature winding for generating a rotating magnetic field in the stator. Then, a magnetic flux generated by flowing a current through the position control winding is superimposed on a magnetic flux generated by the current flowing through the armature winding to create an imbalanced state of the magnetic flux in the stator, and a force is applied in a radial direction of the shaft. (Eg, Ichikawa, Michioka, Chiba, Fukao, "Analysis of Radial Force of Bearingless Reluctance Motor and Configuration of Axial Position Control Device", Electronology D, 11).
Vol. 7, No. 9, 1997 (Heisei 9), 1123-1130
Page). For this reason, there is no need to provide a bearing mechanism for mechanically holding the shaft, and it is possible to eliminate loss that occurs in the bearing portion.

Another example of a motor device for controlling the shaft position of a rotor is disclosed in, for example, Japanese Patent Application Laid-Open No. H8-8449.
There is a motor device described in Japanese Patent Laid-Open Publication No. 1 (1999) -86. This motor device is characterized in that armature windings forming each magnetic pole are independent. By individually controlling these windings, a magnetic flux distribution for rotating the rotor and controlling the position of the shaft is created.

[0005]

However, in the above-described bearingless motor, the above structure is realized by winding the position control winding around the same core slot as the armature winding. For this reason, the number of turns of the armature winding that can be wound in one slot is limited, and the generated torque is inevitable when compared with a motor having only an armature winding on a core of the same size. Become smaller. Further, since it is necessary to wind two types of windings, an armature winding and a position control winding, in the same slot, there is a problem that the structure is complicated and the manufacturing cost is increased.

In the motor device described in Japanese Patent Application Laid-Open No. 8-84491, since it is necessary to control each magnetic pole individually, one side of each winding is in a slot of a stator core and the other side is a stator. It is wound so that it is located outside. In a motor having such a structure, there is a problem that the winding wound outside the stator does not contribute to the generation of the rotational force of the rotor, so that the efficiency is low and the motor becomes large in order to obtain a high output.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has as its object to provide a motor device capable of controlling a shaft position of a rotor with high efficiency, small size, low manufacturing cost.

[0008]

According to a first aspect of the present invention, there is provided a stator core comprising a core element connected to a polyphase AC power supply and divided into an integral multiple of two or more phases of the power supply;
In order to achieve the above object, in a motor device including a plurality of stator windings concentrated on tooth portions of each core body and a rotor disposed inside the stator core, each of the stator windings The wire is characterized by forming a plurality of stator winding groups formed by connecting the stator windings of different phases in a star connection.

In the invention configured as described above, each stator winding group formed by connecting the stator windings in a star shape has an independent neutral point. Therefore, it is possible to individually control the voltage or current at each neutral point. Then, by applying a voltage or a current to the neutral point, the current flowing through the stator windings of each phase constituting the stator winding group can be imbalanced. As a result, these currents can create an imbalance in the magnetic flux created in the stator, generating a force that displaces the rotor in its radial direction. In this way, by applying the radial force to the rotor, the load on the bearing can be reduced and mechanical loss can be reduced, and failure due to wear of the bearing can be reduced and the life can be extended. Therefore, the frequency of maintenance work and the cost thereof can be reduced.

Further, according to the present invention, since each stator winding is concentratedly wound around each tooth portion of the divided core element body, the stator core can be provided in comparison with a general distributed winding system. The space factor of the armature winding with respect to the slot can be increased, and as a result, the efficiency of the motor can be improved. Further, since the shapes of the core body and the stator winding can all be made the same, the manufacturing cost can be reduced.

Further, in the invention described in claim 2, each of the stator winding groups is connected to the first phase of the power supply and the stator winding is connected to the first phase. The first coil is disposed at a position substantially opposite to the stator winding.
And the above-mentioned stator windings connected to each phase other than the above phase.

In the invention having such a configuration, the portion where the magnetic flux is strengthened and the portion where the magnetic flux is weakened by the above-described control of the neutral point appear in the stator at substantially opposite positions. Therefore, the vector of the force generated at both positions due to the imbalance of the magnetic flux and acting on the rotor is in the same direction, and the resultant force is a force along the radial direction passing through the center axis of the stator. It can be performed efficiently. Then, by individually controlling the voltage or current at the neutral point of each stator winding group and generating such a force in two or more different radial directions, the rotor position can be arbitrarily controlled. Becomes possible.

Here, when the type of the motor is, for example, an embedded magnet type motor having a rotor in which a permanent magnet is embedded, the magnetization pattern on the outer peripheral portion of the rotor is such that N poles and S poles appear alternately. . In such a case, for example, when it is desired to cause a current to flow through one winding of the stator to generate a force to draw the rotor, the current flows depending on whether the rotor magnetic pole located near the stator winding is an N pole or an S pole. It is necessary to change the polarity of the current.

According to a third aspect of the present invention, to achieve the above object, a rotor angle detecting means for detecting a rotation angle of the rotor, and a rotor based on rotation angle information detected by the rotor angle detecting means. Control means for generating a position control signal and supplying the position control signal to a neutral point of each of the stator winding groups to unbalance a gap magnetic flux at a geometrically opposed position between the rotor and the stator core. Features.

According to the present invention, the direction of the rotor magnetic pole can be determined by detecting the relative rotation angle of the rotor with respect to the stator. Then, by generating a rotor position control signal corresponding to the direction of the rotor magnetic pole, a force in a desired direction can always be generated.

Further, the invention according to claim 4 further comprises a position detecting means for detecting a relative position of the rotor with respect to the stator core in a radial direction, wherein the control means comprises:
It is characterized in that the rotor position control signal is generated based on the rotation angle information by the rotor angle detection means and the rotor position information by the position detection means.

According to the present invention, the rotor is held at an arbitrary position with respect to the stator core by detecting a relative position of the rotor with respect to the stator core and generating a rotor position control signal based on the position information. Can be.

Further, the invention according to claim 5 further comprises vibration detecting means for detecting vibration of a motor body containing the stator core and the rotor, and the control means comprises:
The method is characterized in that the rotor position control signal is generated based on the rotation angle information by the rotor angle detecting means, the rotor position information by the position detecting means, and the vibration information by the vibration detecting means.

In the invention configured as described above, when the motor main body is displaced or vibrated by receiving an external force, a force for generating the same displacement or vibration as that of the motor main body is applied to the rotor, so that the motor main body and the stator can be moved. The relative position of the rotor can be kept constant. Therefore, it is possible to reduce the gap between the stator and the rotor, which was conventionally widely used to enhance vibration resistance,
As a result, it is possible to achieve both motor efficiency and vibration resistance.

The invention according to claim 6 is characterized in that the support structure of the shaft of the rotor in the motor body is bearingless.

According to the invention configured as described above, the rotor can be held in a non-contact manner by magnetically supporting the rotor shaft. As a result, it can be used under a high vacuum where rotation is difficult and under an ultra-high speed rotation. Further, since mechanical loss due to friction of the bearing can be eliminated, the efficiency of the motor can be improved.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A motor device according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a plan view showing a state where the stator of the motor device is assembled, FIG. 2 is a connection diagram of stator windings of the motor device, FIG. 3 is an explanatory view of the operation principle of the present invention, and FIG.
6 are current waveform diagrams for explaining operation, FIG. 7 is an operation explanatory diagram, and FIG. 8 is a block diagram of a control system.

As shown in FIG. 1, in this embodiment, the stator 1 is concentrated on the stator core 3 composed of the core element 2 formed by dividing into nine parts and the teeth of each core element 2. U, V, and W phases, and the stator windings 4 </ b> A to 4 </ b> I, and a wiring 40 connecting these stator windings to each other. The stator 1, a rotor to be described later, and a motor housing accommodating them constitute a motor body. Thus, the motor body of this embodiment is a motor driven by a three-phase AC power supply.

Each stator winding 4A-4I and wiring 40
Are connected as shown in FIG. That is, the winding 4A connected to the U-phase is
V-phase and W-phase
The windings 4E and 4F connected to the phase are connected at a neutral point N1. Thus, the windings 4A, 4E and 4
F constitutes a first stator winding group 41 connected in a star shape. Similarly, windings 4D, 4H, 4I and windings 4
G, 4B, and 4C are star-connected at neutral points N2 and N3, respectively, to form second and third stator winding groups 42, 4 respectively.
3. The stator 1 has a stator core 3 and these three sets of stator winding groups 41, 42 and 4.
3 are arranged with a rotational symmetry of 120 °.

The principle that the motor body generates a force in the radial direction will be described with reference to FIG. FIG. 3 is a principle diagram for explaining the principle of generation of a radial force in the motor body. In this figure, in order to explain the principle of generation of force by one set of stator windings, windings 4A, 4E,
Only 4F is shown. Here, a state in which the rotor 5 disposed inside the stator 1 is rotating at a constant rotation speed will be considered. When no voltage or current is applied to the neutral point N1 from the outside, the winding 4A connected to the U-phase, the winding 4E connected to the V-phase, and the winding 4 connected to the W-phase
F has the same size and the phase is 120 ° from each other
Currents ia, ie, and if different from each other (the direction of each current is positive in the direction flowing from the outside toward the winding; the same applies hereinafter). The potential of N1 is always 0.

Here, for example, as shown in FIG.
Consider a case where a negative voltage Vn1 is applied to the neutral point N1 at the moment when 0, ie <0, and if <0. At this time, the power supply voltage of the U-phase is positive, and the potential at the neutral point N1 decreases, so that the potential difference between both ends of the winding 4A connected to the U-phase increases, so that ia increases. Therefore, gap 1
The magnetic flux of 0 increases. On the other hand, at this time, the V-phase and W-phase power supply voltages are negative, so that the windings 4E, 4F
Is reduced, ie and if decrease, and the magnetic flux in the gap 11 decreases accordingly. Thus, by applying the negative voltage Vn1 to the neutral point N1, the magnetic flux in the gap 10 increases while the magnetic flux in the gap 11 decreases. For this reason, the gap 1 which is geometrically opposed
Imbalance of the magnetic flux at 0 and the gap 11 occurs, and a force F in the direction of the arrow shown in FIG. Conversely, when the potential at the neutral point N1 is positive, the increase and decrease of the gap magnetic flux acts in the opposite manner, and the direction of the force is opposite to the arrow in FIG.

In the above example, the voltage applied to the neutral point N1 has been described as the DC voltage Vn1, but in an actual motor device, the magnitude and polarity of the voltage and current of each phase change every moment. It goes without saying that the voltage applied to the neutral point N1 also needs to be changed accordingly.

In the above example, a radial force is generated by applying a voltage to the neutral point N1, but it is also possible to inject a positive or negative current into the neutral point N1.
It is possible to create the above-mentioned magnetic flux imbalance and generate a radial force.

As described above, the first stator winding group 41
Controls the voltage or current at the neutral point N1 so that the winding 5A and the windings 4E and 4
A force can be applied in the direction along the axis facing F, that is, in the direction of the arrow shown in FIG.

Similarly, the second and third stator winding groups 4
2 and 43 can also generate a force in the direction along the opposing axis of the windings constituting each by controlling the voltage or current at the neutral points N2 and N3, and control them appropriately. As a result, the rotor 5
To any direction. For example, when the motor device is rotating at a certain speed,
As shown in FIG. 4, currents iu, iv, and iw having the same magnitude and having a phase shifted from each other by 120 ° flow through terminals of each phase flowing from the power supply. Here, the neutral point N1,
For N2 and N3, in1, i shown in FIG.
Consider a case where currents n2 and in3 are injected. At this time, the current flowing through each of the windings 4A to 4I has a waveform as shown in FIG. That is, the winding 4
The current flowing through A, 4B and 4I increases while the current flowing through the other windings decreases. Therefore, while the magnetic flux increases in the gaps 10A, 10B and 10I shown in FIG. 7, the magnetic flux decreases in the other gaps,
As a result, a force in the direction of the arrow shown in FIG.

As described above, each stator winding group 41, 42
By properly controlling the voltage or current at each of the neutral points N1, N2 and N3 provided in
It is possible to control the position by applying a force of an arbitrary magnitude in an arbitrary radial direction. In addition, the rotation speed and output of the rotor 5 can be controlled by adjusting the power supply voltages of the U, V, and W phases as necessary. Therefore, the motor device of this embodiment is capable of controlling the rotation of the rotor and controlling the rotation. , And control of the rotor position can be performed independently of each other.

Next, the control system of this motor device will be described.
This will be described with reference to FIG. 8, which is a block diagram of a control system.
The motor device shown in FIG. 8 includes a permanent magnet type three-phase synchronous motor main body 20 and a control unit 30 that controls the main body. The motor body 20 includes a stator 1 as shown in FIG.
And a permanent magnet rotor 5 provided inside the stator 1 and having a permanent magnet embedded in the outer periphery thereof, a motor housing 21 accommodating them, and a shaft 22 connected to the rotor 5 and transmitting its power to the outside. And consists of In this motor device, a bearing for holding the shaft 22 with low friction during rotation is not provided. That is, the motor body 20 is a bearingless motor. The rotor 5 has a permanent magnet type as described above,
A cage type, a reluctance type, or the like can be used.

The motor housing 21 is provided with position detecting sensors 23 and 24 for detecting the position of the shaft 22 in the x and y directions shown in the figure. As the position detection sensor, for example, an eddy current displacement sensor can be used.

Further, the motor body 20 is provided with a speed sensor 25 for detecting the rotational angular speed of the rotor 5. The speed sensor 25 can be realized by, for example, a combination of a Hall element provided in the housing 21 and a permanent magnet attached to the shaft 22. Then, the rotation angle of the shaft 22 can be obtained as a time integral value of the rotation angular speed detected by the speed sensor 25.

On the other hand, the control unit 30 comprises a rotation control unit 31 for controlling the rotation of the motor and a position control unit 34 for controlling the position of the rotor 5.

The rotation control section 31 compares the rotation angular velocity information detected by the speed sensor 25 with a preset or optionally given target value of the rotation angular velocity, and generates a rotation control signal according to the result. Motor control circuit 3
2 and a motor driving inverter 33 that generates a three-phase AC voltage based on the rotation control signal and drives the motor 20. On the other hand, the position control unit 34 compares the shaft position information detected by the position detection sensors 23 and 24 with a preset or occasionally given target value of the shaft position, and performs radial position control according to the result. A position control circuit 35 for generating a signal and a speed sensor 2
5, a rotation angle modulation circuit 36 for generating a position control signal based on the rotation angular velocity information and the radial position control signal detected by step 5, and a three-phase AC voltage based on the position control signal to generate each stator winding group. And a shaft position control inverter 37 that supplies the neutral point.

In this motor device, the battery 38
The battery 38 supplies power to each of the circuits and the motor.

In FIG. 8, α, β, and ω are the values of the shaft 22 detected by the sensors 23, 24, and 25, respectively.
, The position of the shaft 22 in the y direction, the shaft 2
2 represents the actual measured values of the rotational angular velocities, α *, β *, ω
* Indicates these target values which are set in advance or given as needed.

In this motor device, the rotation control unit 31 controls the rotation speed of the motor as described below. The motor control circuit 32 compares the rotational angular velocity information ω detected by the velocity sensor 25 with a preset or given rotational angular velocity target value ω *, and reduces the difference to obtain the actual measurement value ω. It outputs three-phase rotation control signals iu *, iv *, iw * for approaching ω *. Specifically, ω and ω * are input to the PI controller, and the output signals thereof are subjected to rotational coordinate conversion and two-phase to three-phase conversion, thereby obtaining the three-phase rotation control signals iu *, iv *, iw *. Have gained. Then, the motor driving inverter 33 generates a three-phase AC voltage having a predetermined voltage and frequency based on the rotation control signal, and drives the motor 20 to rotate.

Next, the operation of the position control unit 34 will be described. The position control circuit 35 detects the position information α and β of the shaft 22 in the x direction and the y direction detected by the position detection sensors 23 and 24, and their target values α * and β * which are set in advance or given as needed. And a radial control signal i for reducing their difference and bringing these measured values closer to their respective target values.
Output α * and iβ *. Specifically, α, β, α *, and β * are input to the PID controller, and the output signals are the above-described radial control signals iα * and iβ *. Then, the rotation angle modulation circuit 36 converts the radial direction control signals iα * and iβ * into rotation coordinates in order to generate a position control signal corresponding to the direction of the magnetic pole provided on the rotor 5,
Further, by performing two-phase to three-phase conversion, the three-phase position control signal in
1 *, in2 *, and in3 * are output. Based on the position control signal thus generated, the shaft position control inverter 37
Generates a voltage having a predetermined waveform and drives the neutral points N1, N2 and N3 to control the position of the shaft 22.

As described above, the motor device of this embodiment controls the rotation of the motor by detecting the rotation speed of the shaft 22 and adjusting the voltage applied to the motor terminal based on the information. . Furthermore, this motor device
The rotation speed of the shaft 22 and the relative position of the shaft 22 with respect to the motor body 20 are detected, and the voltage applied to the neutral points N1, N2, and N3 of each stator winding group is adjusted based on the information, so that the gap is adjusted. The position of the shaft 22 is controlled by forcibly imbalance the magnetic flux and applying a radial force to the rotor 5. As described above, the motor device can individually and arbitrarily control the rotation speed and the shaft position.

Further, in the motor device of this embodiment, since the motor body 20 has a bearingless structure by magnetically holding the rotor 5 and the shaft 22 in a non-contact manner, low loss, long life and lubrication are achieved. It has the feature that it is unnecessary. Therefore, it can be used under high vacuum, cryogenic temperature, and ultra-high-speed rotation, and specifically, is suitable for applications such as a turbo-molecular pump, a cryogenic fluid pump, an ultra-high-speed spindle, and a flywheel for energy storage. It is.

The present invention is not limited to the above-described embodiment, and various changes other than those described above can be made without departing from the gist of the present invention.

For example, in the above-described embodiment, eddy current displacement sensors are used as the position detection sensors 23 and 24, but other displacement sensors using, for example, Hall elements may be used.

In the above embodiment, the speed sensor 2
5, a Hall element provided in the housing 21 and the shaft 2
2 is combined with the permanent magnet attached thereto, but other than this, an optical means such as a photo interrupter may be used.

In the above embodiment, the neutral points N1, N3 of the three stator winding groups 41, 42, 43 are respectively set.
2. The shaft 22 is controlled by controlling the voltage applied to N3.
Is held at an arbitrary position and has a bearingless structure, but the present invention can be applied to a motor having a bearing. For example, used horizontally
By applying the present invention to a motor in which the load applied to the bearing is in a fixed direction, such as a motor in which a downward load is always applied to the shaft due to gravity, a force in a direction opposite to this load can always be applied. By doing so, the load applied to the bearing can be reduced, and wear and failure due to wear can be reduced. In such an application, the above-described radial force may be generated in only one direction, and in this case, the configuration of the control circuit is simplified.

Further, the motor device of the above-described embodiment has a 9
Although the motor device has a divided stator core and is driven by a three-phase power supply, the number of phases of the power supply and the number of poles of the stator are not limited to this, and the number of other power supply phases and the number of stator poles are different. The present invention can be applied to a motor device having the same.

Further, by modifying the control system as follows, a motor device with improved vibration resistance can be constructed. That is, a vibration detection sensor including, for example, an acceleration sensor is provided in the motor housing 21, and vibration information (acceleration information) of the motor body 20 detected by the sensor is input to the position control circuit 35. If the position control circuit 35 outputs the radial position control signals iα * and iβ * in consideration of the vibration information (acceleration information) of the motor body 20 in addition to the vibration information α and β of the shaft 22. Good. Specifically, the shaft 22 is
A control signal that generates a force that follows the zero and produces the same vibration is generated by the radial position control signals iα * and iβ * shown in FIG.
Superimposed on By doing so, even if the motor main body 20 receives an external force and vibrates, the rotor 5 and the shaft 22 are displaced following the vibration, so that the gap between the rotor 5 and the stator 3 is always kept constant. be able to.

Therefore, it is possible to reduce the gap interval, which was conventionally widened to prevent the rotor and the stator from coming into contact with each other due to vibration, and as a result, to improve the vibration resistance without lowering the motor efficiency. The motor device thus configured can be configured. Specifically, for example, when the present invention is applied to a hybrid vehicle in which an internal combustion engine and a motor are combined, the gap interval can be reduced while ensuring vibration resistance. It is possible to reduce the efficiency and improve the efficiency. Further, for example, in the case of a permanent magnet type motor, the amount of magnets used can be reduced and the manufacturing cost can be reduced. In addition, since the inductance of the motor can be increased by reducing the gap interval, the reluctance torque generated by the difference in inductance in the salient pole rotor can be effectively used, and the motor generated by increasing the generated torque and improving the power factor can be used. Efficiency can be improved.

[0050]

As described above, according to the first aspect of the present invention, each stator winding group formed by connecting the stator windings in a star shape has an independent neutral point. And
By controlling the voltage or current applied to them, a gap flux imbalance can be created and a radial force can be generated to control the shaft position.

The load on the bearing can be reduced by applying the above-mentioned force to the shaft, so that the frequency of failures caused by wear of the bearing can be reduced and the maintenance cost can be reduced.

Further, since the stator is constituted by the concentrated winding method of the divided cores, the space factor of the windings can be increased to provide a small and highly efficient motor device, and all the cores and the windings can be provided. Since they can have the same shape, they are excellent in mass productivity and low in cost.

According to the second aspect of the present invention, the imbalance of the magnetic flux occurs between the gaps at geometrically opposed positions, so that the forces generated in both gaps are in the same direction, These resultant forces are maximized. Therefore, the rotor position can be efficiently controlled with a small amount of power.

According to the third aspect of the present invention, the direction of the rotor magnetic pole is detected by detecting the relative rotation angle of the rotor with respect to the stator, and the rotor position control signal is generated based on this. In addition, an appropriate position control signal can be generated according to the direction of the magnetic pole of the rotor, and the control of the rotor position can be performed stably.

According to the fourth aspect of the present invention, since the relative position of the rotor with respect to the stator is detected and the rotor position control signal is generated based on the detected position, the rotor is held at an arbitrary position with respect to the stator. It becomes possible.

According to the fifth aspect of the present invention, since the displacement of the motor main body is detected and a force for generating the same displacement is applied to the rotor, even if the motor main body vibrates, the rotation of the rotor with respect to the stator is performed. The position can be kept constant, and the vibration resistance of the motor can be increased. further,
By improving the vibration resistance, the gap between the stator and the rotor can be reduced, so that the motor efficiency can be increased, and the size and output can be reduced.

According to the sixth aspect of the present invention, the shaft is magnetically supported in a non-contact manner utilizing the above-mentioned effects, and the motor device is made bearingless, so that there is no problem of lubrication or wear. And a motor device that can be used under a high vacuum or at an ultra-high speed.

[Brief description of the drawings]

FIG. 1 is a plan view of a stator according to an embodiment of the present invention.

FIG. 2 is a diagram showing connection of stator windings in FIG. 1;

FIG. 3 is a diagram illustrating a principle of generation of a force acting in a radial direction.

FIG. 4 is a diagram showing a waveform of a current flowing from a power supply to a motor.

FIG. 5 is a diagram showing a waveform of a current injected into a neutral point.

FIG. 6 is a diagram showing a waveform of a current flowing through each stator winding.

FIG. 7 is a diagram showing the distribution of magnetic flux generated by this current.

FIG. 8 is a block diagram of a control system according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stator 2 Core body 3 Stator core 4A-4I Stator winding 40 Wiring 41, 42, 43 Stator winding group 5 Rotor 10, 11 Gap 20 Motor body 21 Motor housing 22 Shaft 23, 24 Position detection sensor 25 Speed sensor 30 Control Part 31 rotation control part 34 position control part N1, N2, N3 neutral point

Continued on the front page F term (reference) 5H002 AA09 AB06 AB08 AE06 AE08 5H550 AA16 BB02 CC02 DD03 DD04 DD09 GG01 HB07 LL02 LL34 5H603 AA01 BB01 BB08 BB09 BB12 CA01 CB02 CC11 EE11 5H607 BB01 BB06 BB07 BB06 BB07

Claims (6)

[Claims] 1. A stator core comprising a core element connected to a polyphase AC power supply and divided into an integral multiple of two or more phases of the power supply, and a toothed portion of each of the core elements is provided in a concentrated manner. A motor device comprising: a plurality of stator windings; and a rotor disposed inside the stator core, wherein each of the stator windings is a star winding group formed by star-connecting the stator windings having different phases from each other. The motor device characterized by forming a plurality of. 2. Each of the stator winding groups is located at a position substantially opposed to the stator winding connected to a first phase of the power supply and the stator winding connected to the first phase. 2. The motor device according to claim 1, further comprising: the stator windings arranged and connected to each phase other than the first phase. 3. 3. A rotor angle detecting means for detecting a rotation angle of the rotor, and a rotor position control signal is generated based on the rotation angle information detected by the rotor angle detecting means to generate each of the stator winding groups. 3. The motor device according to claim 2, further comprising control means for supplying a neutral point to unbalance a gap magnetic flux at a geometrically opposed position between the rotor and the stator core. 4. The apparatus according to claim 1, further comprising: a position detector for detecting a relative position of the rotor with respect to the stator core in a radial direction, wherein the controller is configured to control the rotation angle information by the rotor angle detector and the rotor by the position detector. The motor device according to claim 3, wherein the rotor position control signal is generated based on position information. 5. The apparatus according to claim 1, further comprising: a vibration detecting unit configured to detect a vibration of a motor body containing the stator core and the rotor, wherein the control unit includes the rotation angle information by the rotor angle detecting unit, and the rotor by the position detecting unit. The motor device according to claim 4, wherein the rotor position control signal is generated based on position information and vibration information obtained by the vibration detection unit. 6. The motor device according to claim 1, wherein a support structure of the shaft of the rotor in the motor body is bearingless.