JP2000184672A - Four-phase reluctance motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase an output torque by arranging two magnetic body fixing armatures where two magnetic poles of two phases are provided. SOLUTION: In a reluctance motor, magnetic poles 2a, 2c, 2e, and 2g are formed on a circumferential surface inside one fixing armature 1a while width in a circumferential direction is set to an electric angle of 180 degrees, and magnetic poles 2b, 2d, 2f, and 2h are formed on the circumferential surface inside the other armature 1b while the width in the circumference direction is set to an electric angle of 180 degrees. Also, salient poles 9a, 9b, 9c, 9d, 9e, and 9f are formed on the circumferential surface outside a rotor 8a being provided inside the armature 1a while the width in the circumferential direction is set to an electric angle of 180 degrees, and salient poles 9g, 9h, 9i, 9f, 9h, and 9l are formed on the circumferential surface outside a rotor 8b being provided inside the armature 1b while the width in the circumferential direction is set to an electric angle of 180 degrees. Therefore, since the number of the magnetic poles being provided in one fixing armature becomes four, the inner surface of the armature is divided into four, utilizing the volume of an excitation coil per magnetic pole at the maximum, and hence increasing an output torque.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a four-phase reluctance motor used as a drive source for an electric vehicle, a fluid machine, and the like. The present invention relates to a four-phase reluctance motor having a configuration capable of increasing the power.

[0002]

2. Description of the Related Art One of conventional four-phase reluctance motors is disclosed.
In the example, eight magnetic poles are arranged on the circumferential surface, and the first,
One fixed armature provided with the second, third, and fourth phase excitation coils, and six salient poles are arranged on the circumferential surface of the fixed armature opposed to the circumferential surface via a gap. It consisted of one rotor. Another example of a conventional four-phase reluctance motor is a combination of a fixed armature and a rotor having a plurality of magnetic poles and exciting coils and salient poles on the circumferential surface, each of which has a first, a second, and a third. It was configured by providing four sets of the third and fourth phases.

[0003]

Therefore, the conventional 4
In one example of the phase reluctance motor, eight magnetic poles are provided on the circumferential surface of one fixed armature, so that the volume of the exciting coil per magnetic pole becomes small and the output torque becomes small. there were. Also, in order to increase the output torque of one example of the conventional four-phase reluctance motor, when two phases are energized simultaneously, the armature magnetic pole excited to the N-pole has an area facing the rotor salient pole. Since the area of the armature pole excited by the S pole facing the rotor salient pole is different, the amount of magnetic flux passing through the facing surface is also different, so the magnetic flux leaks between the armature pole and the rotor salient pole that are not excited. Therefore, there is a problem that the output torque is reduced. Another example of the conventional four-phase reluctance motor has the problem that the length is increased because the four fixed armatures and the rotor are arranged in the axial direction, the structure is complicated, and the manufacturing cost is increased. Was. Further, since the four fixed armatures are sequentially excited one by one, there is a problem that the utilization rate of the fixed armature is low.

[0004]

In order to solve the above-mentioned problems, an electric angle of 360 to 180 degrees (a mechanical angle of 30 to 22.5 degrees) in the circumferential direction is set on the circumferential surface.
Two fixed magnetic armatures each provided with four magnetic poles arranged at equal circumferentially spaced angles of 405 degrees to 405 degrees (mechanical angle of 60 degrees to 67.5 degrees); A circumferential surface opposed to each circumferential surface of the above through a gap has an electrical angle of 180 ° to 135 ° (mechanical angle of 30 ° to 22.5 °) and a circumferential width of 180 ° to 225 ° (mechanical angle). Two magnetic rotors each provided with six salient poles arranged at equal circumferential separation angles (angles of 30 degrees to 37.5 degrees), and the two fixed armatures and rotations described above. One set and the other set of the armature combination are coaxially spaced apart from each other in the axial direction, and the phase where the salient pole of one rotor faces the magnetic pole of one fixed armature and the other A phase difference of 90 degrees electrical angle (15 degrees mechanical angle) provided between phases where the salient pole of the other rotor faces the magnetic pole of the fixed armature. Having a first phase and a third phase excitation coil provided on the magnetic pole of the one fixed armature, and a second phase and a fourth phase excitation coil provided on the magnetic pole of the other fixed armature It is.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment in which the present invention is applied to an electric motor of an electric power steering of an automobile will be described with reference to the drawings. FIG. 1 shows the electric power steering 4.
FIG. 3 is a longitudinal sectional view of a phase reluctance motor. FIG. 2 shows X in FIG.
-X sectional drawing. FIG. 3 is a sectional view taken along line YY of FIG. FIG. 4 is an explanatory view of a position detecting magnet and a pole element. FIG. 5 is a developed view of FIGS. 2, 3 and 4. In FIG. 1 to FIG. 5, the magnetic poles 2a, 2c, 2
e, 2g, the width in the circumferential direction is 180 degrees electrical angle (mechanical angle 30 degrees).
Degrees), and are arranged at circumferentially equal angles of 360 degrees electrical angle (60 degrees mechanical angle). Magnetic poles 2a, 2e
The first phase excitation coils 3a and 3e are wound around the
The third phase excitation coils 3c and 3g are wound around c and 2g, respectively, and when the excitation coils 3a, 3e and 3c and 3g are energized, the magnetic poles 2a and 2c are excited to the N pole,
e and 2g are configured to be excited to the S pole.

The magnetic poles 2b, 2d, 2f, and 2h are arranged on the inner circumferential surface of the other fixed armature 1b so that the width in the circumferential direction is equal to the electrical angle 18.
They are formed at 0 ° (mechanical angle 30 °) and are arranged at equal circumferential separation angles of 360 ° electrical angle (60 ° mechanical angle). The magnetic poles 2b and 2f have second-phase excitation coils 3b and 3f, respectively.
Is wound, and the fourth-phase excitation coil 3 is provided on the magnetic poles 2d and 2h.
d, 3h are wound, and the exciting coils 3b, 3f
, 3d and 3h, the magnetic poles 2b and 2f are excited to the N pole, and the magnetic poles 2f and 2h are excited to the S pole. In FIG. 1, the two fixed armatures 1
a and 1b are excitation coils 3a, 3c, 3e, 3g and 3b,
3d, 3f, and 3h are fixed inside the cylindrical frame 4 so as to be spaced apart in the axial direction so as not to abut. Lids 6a, 6b are provided at both ends of the frame 4, and bearings 10a, 10b are provided at the center thereof, and a hollow rotary shaft 5 is rotatably supported.

[0007] Salient poles 9a, 9b, 9c, 9d, 9e and 9f are formed in the circumferential direction on the outer circumferential surface of the rotor 8a provided so as to face the inner circumferential surface of the armature 1a via a gap. Is formed to have an electrical angle of 180 degrees (mechanical angle of 30 degrees), and an electrical angle of 18 degrees.
The rotors 8 a are arranged at equal separation angles of 0 degrees (mechanical angle 30 degrees), and the center of the rotor 8 a is fixed to the outer periphery of the rotating shaft 5. The armature 1a and the rotor 8a form one combination A. Further, salient poles 9g, 9h, 9i, 9j, 9k, 9l are provided on the outer circumferential surface of the rotor 8b, which is provided so as to face the inner circumferential surface of the armature 1b via a gap, in the circumferential direction. The width is formed at an electric angle of 180 degrees (mechanical angle of 30 degrees), and the electric angles are arranged at equal circumferential angles of 180 degrees (mechanical angle of 30 degrees). It is fixed to the outer circumference. The armature 1b and the rotor 8b form another combination B. As described above, in the present invention, two magnetic poles of each of two phases are provided, that is, four magnetic poles are provided on one fixed armature, and two fixed armatures are arranged. Thus, the volume of the exciting coil is maximized, and the wasted space is minimized. In addition, the excitation coil can be inserted into the magnetic pole with the high-density coil wound outside without directly wrapping it around the magnetic pole of the armature, so that the output torque and efficiency increase, and the manufacture of the armature becomes easier. ,
The connection of the lead wire is simple, and the manufacturing cost of the reluctance motor is reduced. Therefore, a four-phase reluctance motor having high output torque and efficiency can be made relatively small and manufactured at low cost.

In FIG. 1, a ball nut 11 sandwiched by a thrust receiving housing 12 is fixed to the right end of the rotating shaft 5, and the relative position between the armature magnetic pole and the rotor salient pole is detected at the left end of the rotating shaft 5. Detection rotor 17 is fixed. A rack shaft 14 having a ball screw 13 fitted with the ball nut 11 and reciprocating in the axial direction by forward / reverse rotation of the rotary shaft 5 is inserted through a hollow portion at the center of the rotary shaft 5. 1, 4 and 5, a position detecting magnet 18 is fixed to the outer periphery of the position detecting rotor 17, and salient poles 9a, 9b, 9c, 9 of the rotor 8a are provided.
A portion having the same phase as the circumferential width of d, 9e, and 9f is magnetized to the N pole, and a portion having the same phase as one circumferential angle of the salient pole is magnetized to the S pole. Position detecting Hall elements 19a, 19b, 19c, and 19d are provided on the inner peripheral surface of the lid 6a opposed to the outer peripheral surface of the position detecting magnet 18 via a gap in the circumferential direction from a position in phase with the end of the magnetic pole 2a. Electrical angle of 450
It is provided at equal intervals of 75 degrees (mechanical angle 75 degrees).

An energization control circuit for driving the four-phase reluctance motor constructed as described above according to the present invention will be described. In FIG. 8, the first series-connected
The phase excitation coils 3a and 3e are 30a, the series connected second phase excitation coils 3b and 3f are 30b, the series connected third phase excitation coils 3c and 3g are 30c,
The fourth-phase exciting coils 3d and 3h connected in series
Then, the negative side of the first phase excitation coil 30a, the positive side of the second phase excitation coil 30b, and the third phase excitation coil 30a
c and the positive side of the fourth phase excitation coil 30d are 1
Connected to one. The positive electrodes of the first-phase excitation coil 3a and the third-phase excitation coil 3c are connected to the negative electrodes of the positive-side switching elements 20a and 20c, respectively.
Second phase excitation coil 3b and fourth phase excitation coil 3d
Are connected to the positive electrodes of the switching elements 20b and 20d on the negative electrodes, respectively. The positive electrodes of the positive switching elements 20a and 20c are connected to the power supply positive electrode 21a, respectively.
The negative electrodes of b and 20d are connected to the power negative electrode 21b, respectively.

The diodes 22a, 22b, 22 are connected between the positive poles of the first, second, third, and fourth phase armature coils 30a, 30b, 30c, 30d and the DC power negative pole 21b.
c are connected in the reverse direction, and diodes 22d, 22e, 22c are provided between the negative side of the first, second, third, and fourth phase armature coils 30a, 30b, 30c, 30d and the DC power positive electrode 21a.
22f is connected in the opposite direction. 4 and 5, each of the Hall elements 19a, 19b, 19c, 1
The positive or negative signal output from 9d is output as a conduction signal curve of FIG. 7 through a signal generation circuit (not shown). A flip-flop circuit or the like is provided in the energization signal generation circuit so that the switching element 2
0a or 20c and switching element 2
One of 0b and 20d is always ON.

Next, the operation of the four-phase reluctance motor according to the present invention will be described. The time chart of the position detection signal curve shown in FIG. 6 is a positive signal (N signal in the figure) when the N pole of the position detection magnet faces the Hall elements 19a, 19b, 19c, and 19d in FIGS.
Is output, and a negative signal (S signal in the figure) when the S pole faces each other
Is output. When rotating the rotors 8a, 8b in the directions of arrows R in FIGS. 2, 3, and 5, the Hall elements 19a, 19
The positive signals of the position detection signal curves of FIG. 6 output from b, 19c, and 19d are converted into signals for turning on the switching elements 20a, 20b, 20c, and 20d via a signal generation circuit (not shown) and output. Signal input terminal 24
a, 24b, 24c, 24d.

In FIGS. 2, 3, 5, 6, 7, and 8, when the magnet is rotated in the direction of arrow R from the relative positions of the magnetic poles and salient poles in FIGS. 18
(Hereinafter, the name of the magnet for position detection is omitted.)
Since the Hall element 19d facing the pole outputs a positive signal 28c, the energization signal 34c is input to the signal input terminal 24d, and the switching element 20d is ON. Further, the opposition of the Hall element 19c with the N pole is terminated, and the Hall element 19c is turned off.
As for a, the opposition to the N pole is started, and a positive signal 25a is output. Since the energization signal 31a is input to the signal input terminal 24a and the switching element 20a is turned on, the first phase excitation coil 30a and the fourth phase excitation coil 30d are energized, and the first phase magnetic poles 2a, 2e and the fourth phase excitation coil 30a are turned on. When the magnetic poles 2d and 2h are excited, the salient poles 9a and 9d and 9i and 91 are attracted and the rotor 8
a and 8b rotate in the arrow R direction.

At the time of turning by 90 degrees in electrical angle, the switching element 20a is ON because the Hall element 19a continues to face the N pole. The Hall element 19b starts facing the N pole and outputs a positive signal 26a. Since the energizing signal 32a is input to the signal input terminal 24b and the switching element 20b is turned on, the first-phase exciting coil 30a is continuously energized, and the second-phase exciting coil 30b is energized, so that the first-phase magnetic pole is turned on. 2a, 2e and third phase magnetic pole 2
When b and 2f are excited, salient poles 9a, 9d and 9g and 9j are attracted, and rotors 8a and 8b rotate in the direction of arrow R. The opposition of the Hall element 19d with the N pole ends, and the positive signal 28c
Is stopped, and the energization signal 34c of the signal input terminal 24d is stopped.
Stops. Therefore, the switching element 20d is O
FF is performed, and the energization of the fourth phase excitation coil 30d is cut off, and the excitation of the magnetic poles 2d and 2h disappears.

Further, at a position rotated by 90 electrical degrees, the switching element 20b is ON because the Hall element 19b continues to face the N pole. The Hall element 19c starts facing the N pole, and outputs a positive signal 27a.
Since the energization signal 33a is input to the signal input terminal 24c and the switching element 20c is turned on, the second phase excitation coil 3c is turned on.
0b is continuously energized and energized to the third-phase excitation coil 30c, and the second-phase magnetic poles 2b, 2f and the third-phase magnetic poles 2c, 2g are excited to produce salient poles 9g, 9j, 9b, 9
e is sucked and the rotors 8a and 8b rotate in the direction of the notch R. The Hall element 19a completes facing the N pole and the positive signal 2
The output of 5a is stopped and the energizing signal 3 of the signal input terminal 24a is
1a stops. Therefore, the switching element 20a
Is turned off, the energization of the first phase excitation coil 30a is cut off, and the excitation of the magnetic poles 2a, 2e disappears.

Further, at a position rotated by 90 degrees in electrical angle, the hole cable 19c continues to face the N pole, so that the switching element 20c is ON. Hall element 19d is N
Opposition with the pole is started, and a positive signal 28a is output. Since the energization signal 34a is input to the signal input terminal 24d and the switching element 20d is turned on, the third phase excitation coil 30d is turned on.
c is continuously energized and the fourth-phase excitation coil 3
0d is energized, the third phase magnetic poles 2c, 2g and the fourth phase magnetic poles 2d, 2h are excited, salient poles 9b, 9e, 9h and 9k are attracted, and the rotors 8a and 8b rotate in the direction of arrow R. I do.
The Hall element 19b stops facing the N-pole and the positive signal 26a
Is stopped and the energization signal 32a of the signal input terminal 24b is stopped.
Stops. Therefore, the switching element 20b is
FF is performed, the energization of the third phase excitation coil 30b is cut off, and the magnetic pole 2
Excitation of b and 2f disappears.

Further, at the position rotated by 90 electrical degrees, the phase of the magnetic poles and salient poles shown in FIGS. 2, 3 and 5 becomes the same.
a and 8b continue rotation in the direction of arrow R. Rotor 8a,
When rotating 8b in the direction opposite to the arrow R in FIGS. 2, 3, and 5, a negative signal (S signal in FIG. 6) of the position detection signal curve in FIG. 6 output from the Hall elements 19a,. Is a switching element 20 via a signal generation circuit (not shown).
a, ..., are converted to signals that turn on 20d and output,
The signal is input to each signal input terminal. The operation is the same as that in the case of the rotation in the direction of the arrow R, and the description is omitted. The driving action of the four-phase reluctance motor of the present invention is the same as that of FIG. 8 even when the energization control circuit of FIG. This is the same as the case where the current supply control circuit is used. As described above, in the present invention, one of two magnetic poles of two rivers of each of the fixed armatures of the two fixed armatures provided with two magnetic poles of two phases and the other of the two magnetic poles are provided. Since the magnetic poles of the phases are always alternately excited, the armature magnetic poles of two phases of one fixed armature are not simultaneously excited. Therefore, the magnetic flux does not leak between the non-excited armature magnetic poles and the rotor salient poles, so that the output torque does not decrease, and the utilization rate of the fixed armature increases and the output increases.

Another embodiment of the present invention has the same configuration except that the circumferential width of the magnetic poles and salient poles is smaller than that of the above-described first embodiment. 9
The description will be made only with reference to the development view of FIG. 9 are the same as those in FIG. In FIG. 9, one fixed armature 1
The magnetic poles 2a, 2c, 2e, and 2g are formed at an electrical angle of 135 degrees (mechanical angle of 22.5 degrees) on the inner circumferential surface of a.
They are arranged at an equal circumferential separation angle of 5 degrees (mechanical angle 67.5 degrees). The magnetic poles 2b, 2d, 2f, and 2h have a circumferential width of 135 degrees (mechanical angle 22.5 degrees) on the inner circumferential surface of the other fixed armature 1b.
They are arranged at equal circumferential separation angles of 05 degrees (mechanical angle 76.5 degrees). One and the other fixed armatures 1a and 1b
Each of the magnetic poles is wound with an exciting coil of each phase, and has N poles and S poles, respectively.
The configuration in which the poles are excited is the same as in the first embodiment. The salient poles 9a, 9b, 9c, 9d, 9e, 9f have a circumferential width on the outer circumferential surface of the rotor 8a provided so as to face the inner circumferential surface of the armature 1a via a gap. They are formed at an electrical angle of 135 degrees (mechanical angle of 22.5 degrees) and are arranged at an equal separation angle of 225 degrees of electrical angle (mechanical angle of 37.5 degrees). Further, salient poles 9g, 9h, 9i, 9j, 9l are provided on the outer circumferential surface of the rotor 8b provided so as to face the inner circumferential surface of the other armature 1b via a gap in the circumferential direction. The width is formed at an electrical angle of 135 degrees (mechanical angle of 22.5 degrees), and they are arranged at an equal separation angle of 225 degrees of electrical angle (mechanical angle of 37.5 degrees). The configuration and operation of the rotating shaft, bearing, position detecting rotor, position detecting magnet, Hall element, and power supply control circuit of the other embodiment are the same as those of the above-described first embodiment, and a description thereof will be omitted. However, since the magnetic poles and the salient poles are separated at the start of energization, the volume of the exciting coil is
Since it is larger than in the embodiment, output and efficiency are improved.
Further, since the phase is advanced, the efficiency at the time of high-speed rotation is improved.

[0018]

According to the four-phase reluctance motor of the present invention, since two fixed armatures each having two magnetic poles of two phases are arranged, one fixed armature is provided. Since the number of magnetic poles is halved to four, the circumferential surface of the armature is divided into four parts, and the volume of the exciting coil per magnetic pole is maximally used, so that the output torque is increased.
Further, since the armature magnetic poles of two rivers in one fixed armature are not simultaneously excited, magnetic flux leaks between the armature magnetic poles that are not excited and the rotor salient poles, so that the output is reduced. The torque does not decrease. Further, since the magnetic poles of one of the two phases of the two fixed armatures are always excited, the utilization rate of the armature is increased and the length of the motor is reduced. The structure is simple and the output torque is increased. In addition, the structure is such that the excitation coil, which is wound at a high density and has the maximum capacity externally, can be inserted into the magnetic poles, increasing output torque and efficiency, making armature easier to manufacture and lowering manufacturing costs. It has the effect of reducing.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a portion in which an embodiment of a four-phase reluctance motor of the present invention is configured in an electric power steering.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is a sectional view taken along line YY of FIG. 1;

FIG. 4 is an explanatory diagram of a position detection magnet and a Hall element.

FIG. 5 is an expanded view of FIGS. 2, 3, and 4;

FIG. 6 is a time chart of a position detection signal curve.

FIG. 7 is a time chart of an energization signal curve and an energization curve.

FIG. 8 is an energization control circuit diagram of a four-phase reluctance motor.

FIG. 9 is a developed view of another embodiment of the reluctance motor of the present invention.

[Explanation of symbols]

1a, 1b Armatures 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h Magnetic poles 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h Excitation coil 4 Frame 5 Rotation shaft 6a, 6b Lid 7a , 7b Gap 8a, 8b Rotor 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9
i, 9j, 9k, 9l Salient pole 10a, 10b Bearing 11 Ball nut 12 Thrust receiving housing 13 Ball screw 14 Rack shaft 15 Rack 16 Pinion housing 17 Position detecting rotor 18 Position detecting magnet 19a, 19b, 19c, 19d Hall element 20a, 20b, 20c, 20d Switching element 21a Power supply pole 21b Power supply negative pole 22a, 22b, 22c, 22d, 22e, 22f Diode 23a, 23b, 23c, 23d, 23e, 23f, 2
3g, 23h, 23i Capacitors 24a, 24b, 24c, 24d Signal input terminals 25a, 25b, 25c, 25m, 25n, 25o, 2
6a, 26b, 26c, 26m, 26n, 26o, 27
a, 27b, 27c, 27m, 27n, 27o, 28
a, 28b, 28c, 28m, 28n, 28o Position detection signal curve 29 Position in phase with end of magnetic pole 2a 30a First phase excitation coil 30b Second sum excitation coil 30c Third phase excitation coil 30d Fourth Phase excitation coils 31a, 31b, 31c, 32a, 32b, 32c, 3
3a, 33b, 33c, 34a, 34b, 34c Energization signal curve and energization curve

Claims (1)

[Claims] 1. An electrical angle of 3 to 180 degrees in a circumferential direction having an electrical angle of 180 to 135 degrees (mechanical angle of 30 to 22.5 degrees).
Two magnetic fixed armatures each having four magnetic poles arranged at equal circumferentially spaced angles of 60 degrees to 405 degrees (mechanical angle 60 degrees to 67.5 degrees); The electrical angle of 180 on the circumferential surface facing each circumferential surface of the
At a circumferential width of 135 to 135 degrees (mechanical angle of 30 to 22.5 degrees) and an electrical angle of 180 to 225 degrees (mechanical angle of 30 to 37.5 degrees) arranged at equal circumferential separation angles The two magnetic rotors provided with the six salient poles, one set of the combination of the two fixed armatures and the rotor, and the other set are separated in the axial direction. Between the phase where the salient pole of one rotor faces the magnetic pole of one fixed armature and the phase where the salient pole of the other rotor faces the magnetic pole of the other fixed armature Phase difference of 90 degrees electrical angle (15 degrees mechanical angle), the first and third phase excitation coils provided on the magnetic poles of the one fixed armature, and the phase difference of the other fixed armature. A four-phase reluctance motor having a second-phase and a fourth-phase excitation coil provided on a magnetic pole.