HK1111529B - Inductor type synchronizer - Google Patents

Description

Induction type synchronous motor

Technical Field

The present invention relates to an induction type synchronous motor. More particularly, the present invention relates to an electric motor or generator including a magnetic material (inductor) that induces a magnetic flux to a predetermined position on a magnetic field side, the rotation of a rotating shaft being synchronized with the change in polarity of an armature.

Background

As shown in fig. 20, in the generator disclosed in JP- ｃA-54-116610 or JP- ｃA-6-86517, ｃA rotating shaft 1 penetrates ｃA support 2 through ｃA bearing, and the support 2 serves as ｃA housing. The field winding 5 is disposed at the periphery of a yoke 4 which is fitted and fixed to the rotating shaft 1, and claw-shaped magnetic poles 6 and 7 are disposed so as to protrude alternately from the left and right sides of the field winding 5, whereby the rotor is formed as one body. Meanwhile, the stator winding 8 is arranged on the bracket 2 so as to face the claw-shaped magnetic poles 6 and 7. Electrical power is slidably supplied to the field winding 5 through slip rings 9.

According to the above-described structure, as shown in the drawing, when a direct current is supplied to the field winding 5 through the slip ring 9 so that an N pole is generated on the right side of the field winding 5 and an S pole is generated on the left side of the field winding 5, the N pole is induced on the claw-shaped magnetic pole 6 protruding from the right side and at the same time, the S pole is induced on the claw-shaped magnetic pole 7 protruding from the left side. Therefore, a plurality of N poles and a plurality of S poles can be alternately generated on the outer circumferential side of the rotor along the circumferential direction thereof.

However, the field winding 5 is formed as a part of the rotor, and it is necessary to supply electric power to the field winding 5 that is rotationally moved through the slip ring 9 by sliding contact. Therefore, the structure becomes complicated. Further, there are problems such as a reduction in life due to contact wear at the slip ring 9, and an instability in power supply due to an instability in sliding contact at the slip ring 9.

Patent document 1: JP-A-54-116610

Patent document 2: JP-A-6-86517

Disclosure of Invention

Problems to be solved by the invention

The present invention has been made in view of the above problems, and has as its object to allow a simple structure for supplying electric power to a coil.

Means for solving the problems

In order to solve the problems, the present invention provides an induction type synchronous motor including:

an excitation stator having an excitation element by which an N pole and an S pole are concentrically formed;

a rotor having an N-pole inductor formed of a magnetic material and configured to face an N-pole of the exciting element, and having an S-pole inductor formed of a magnetic material and configured to face an S-pole of the exciting element, wherein the rotating shaft is fixed to the rotor; and

an armature stator having an armature coil configured to face the N-pole inductor and the S-pole inductor.

According to the above structure, since the field elements and the armature coils are connected to the respective stators, sliding contact parts such as slip rings for feeding electric power to the coils are not required. Therefore, the structure can be simplified, and a reduction in life and instability of power supply due to contact wear at the slip ring, for example, can be solved.

When the rotor rotates, the N-pole inductor moves along the circumference at the N-pole generating position of the excitation stator, while the S-pole inductor moves along the circumference at the S-pole generating position of the excitation stator. Thus, each inductor induces a particular polarity. The field stator and the armature stator may be separated from each other or combined with each other.

In the case where the synchronous machine is an electric motor, power feeding is performed by periodically changing the polarity of the armature coil. Accordingly, an attractive/repulsive force is generated between the armature coil and the N-pole and S-pole inductors, thereby rotating the rotor and generating a driving force of the rotating shaft. In the case of a synchronous machine as a generator, the N-pole inductor and the S-pole inductor are rotated around the shaft by the rotational motion of the rotating shaft, thereby causing an induced current to flow into the armature coil.

An exciting coil around which an exciting element may be wound around an axis of the rotating shaft, and a part of the N-pole inductor may be disposed to face one of an outer circumferential side and an inner circumferential side of the exciting coil, while a part of the S-inductor is disposed to face the other.

According to the above-described structure, when a direct current is supplied to the exciting coil, an N pole is generated on one of the outer circumference side and the inner circumference side of the exciting coil, while an S pole is generated on the other, thereby making it possible to make the N pole and the S pole concentric. Therefore, it is possible to cause the N-pole inductor and the S-pole inductor to generate magnetic fields of multiple poles with a single excitation coil. Accordingly, the manufacturing of the coil winding can be simplified, whereby the manufacturing efficiency can be improved.

Alternatively, the excitation element may be a permanent magnet arranged around the axis of the rotation shaft, and a part of the N-pole inductor is arranged to face the N-pole side of the permanent magnet, while a part of the S-pole inductor is arranged to face the S-pole side of the permanent magnet.

According to the above structure, the permanent magnet is arranged to the excitation stator. Therefore, the manufacturing efficiency of the induction type synchronous motor is improved, and the structure can be simplified.

Further, in the case where the induction type synchronous motor according to the present invention is an induction type motor, the induction type motor can sufficiently handle an output power from 1kW to 5MW even when permanent magnets are used as the exciting elements, thereby reducing the size of the induction type synchronous motor.

At least one of the field element and the armature coil is formed of a superconducting material.

The magnetic permeability of the magnetic material making up each inductor is typically three digits or more greater than the permeability of air. Therefore, the magnetic flux generated by the exciting element mainly passes through the inductor. However, since a predetermined air gap is provided between the field element and each inductor or between the armature coil and the inductor, there is a case where the magnetic resistance is increased, whereby leakage of magnetic flux occurs in which the magnetic flux is deviated toward an undesired direction, and the magnetic flux acting on the output is thus reduced.

When one or both of the field element and the armature coil are formed of a superconducting material, a large current can be fed without fear of heat generation, and the magnetic flux to be generated can be significantly increased. Accordingly, even when leakage of magnetic flux occurs, since the total magnetic flux generated increases, the magnetic flux acting on the output increases, thereby obtaining a large power output. In addition, by superconducting, a large current density can be obtained. Therefore, the size of the field element and the armature coil can be reduced, whereby the size and weight of the synchronous motor can be reduced. As the superconducting material, a bismuth-based or yttrium-based high-temperature superconducting material may be suitably used.

Further, considering the case where the superconducting material cooling structure is provided to exert the predetermined superconducting performance, since the field element and each armature coil are connected to the stator and are not moved therefrom, the refrigerant supply path or the sealing structure can be more easily designed, and the cooling structure can be simplified.

The cross-sectional area of each of the N-pole inductor and S-pole inductor may be constant from one end to the other.

That is, according to the above structure, the magnetic flux generated by the exciting element and introduced into each inductor becomes less likely to saturate in the inductor. Therefore, the magnetic flux can be efficiently introduced into the armature coil.

Meanwhile, the cross-sectional area of the N-pole inductor and the cross-sectional area of the S-pole inductor may be substantially equal.

That is, since the cross-sectional portions of the inductors are made uniform, the attractive/repulsive force generated between the inductors and the armature coils becomes constant, whereby the rotor rotation balance can be stabilized.

A specific structure of the synchronous motor may be an axial air gap structure in which the exciting stator is configured to face one side of the rotor in the axial direction of the rotor with a predetermined air gap therebetween, and the armature stator is configured to face the other side of the rotor in the axial direction of the rotor with a predetermined air gap therebetween,

a rotating shaft fixed to the rotor rotatably passes through and bridges between the field stator and the armature stator, an

The magnetic flux direction of each of the field element and the armature coil is oriented in the axial direction.

Alternatively, it may be a radial air gap structure in which one of the field stator and the armature stator is an outer circumferential tube, and the rotor is disposed within the outer circumferential tube with a predetermined air gap between the stator and the rotor.

THE ADVANTAGES OF THE PRESENT INVENTION

As described above, according to the present invention, both the field element and the armature coil are connected to the stator. Therefore, a sliding contact member such as a slip ring for feeding electric power to the coil is not required. Therefore, simplification of the structure, extension of the life, and stabilization of power feeding are achieved.

Further, when one or both of the field element (field coil) and the armature coil are formed of a superconducting material, a large current can be fed without fear of heat generation, whereby the magnetic flux can be significantly increased. Therefore, even in the case where leakage of magnetic flux occurs, the magnetic flux acting on the output can be increased, thereby allowing a large power output.

In the case where the cross-sectional area of each of the N-pole inductor and the S-pole inductor is constant from one end to the other end, the magnetic flux is not easily saturated in the inductor, whereby the magnetic flux can be efficiently induced to the armature coil side. Further, in the case where the cross-sectional area of the N-pole inductor and the cross-sectional area of the S-pole inductor are substantially equal, the attractive/repulsive force generated between the inductor and the armature coil is constant, whereby the rotor rotational balance can be stabilized.

Drawings

Fig. 1(a) shows a sectional view of an induction type synchronous motor according to a first embodiment of the present invention, and fig. 1(B) shows another sectional view of the induction type synchronous motor as viewed from a position rotated by 90 °.

Fig. 2(a) shows a front view of the rotor, fig. 2(B) shows a sectional view along a line I-I shown in fig. 2(a), fig. 2(C) shows a rear view of the rotor, and fig. 2(D) shows a sectional view along a line II-II shown in fig. 2 (a).

Fig. 3(a) shows a front view of the excitation stator, and fig. 3(B) shows a sectional view along the line I-I shown in fig. 3 (a).

Fig. 4(a) shows a front view of a state in which the rotor and the excited stator are penetrated by the rotating shaft, fig. 4(B) shows a sectional view along a line I-I shown in fig. 4(a), and fig. 4(C) shows a sectional view along a line II-II shown in fig. 4 (a).

Fig. 5(a) shows a sectional view of an induction type synchronous motor according to a first modification of the first embodiment of the present invention, and fig. 5(B) shows a sectional view of the induction type synchronous motor as viewed from a position rotated by 90 °.

Fig. 6(a) and 6(B) show front views of respective excitation stators according to the first modification.

Fig. 7(a) and 7(B) show front views of respective excitation stators according to a second modification.

Fig. 8(a) and 8(B) show front views of respective excitation stators according to a third modification.

Fig. 9(a) shows a sectional view of an induction type synchronous motor according to a second modification of the first embodiment of the present invention, and fig. 9(B) shows a sectional view of the induction type synchronous motor as viewed from a position rotated by 90 °.

Fig. 10 shows a cross-sectional view of an induction type synchronous motor according to a second embodiment.

Fig. 11 shows a cross-sectional view of an induction type synchronous motor according to a third embodiment.

Fig. 12(a) shows a front view of a state in which the rotor and the exciting stator according to the fourth embodiment are penetrated by the rotating shaft, fig. 12(B) shows a sectional view along a line I-I shown in fig. 4(a), and fig. 12(C) shows a sectional view along a line II-II shown in fig. 12 (a).

Fig. 13 shows a cross-sectional view of an induction type synchronous motor according to a fifth embodiment.

Fig. 14 shows a cross-sectional view along the line I-I shown in fig. 13.

Fig. 15 shows a cross-sectional view along the line II-II shown in fig. 13.

Fig. 16 shows a perspective view of the rotor.

Fig. 17 shows a perspective view of a rotor and an excitation stator according to a sixth embodiment.

Fig. 18 shows a cross-sectional view of the rotor and the excited stator.

Fig. 19 shows a cross-sectional view from a position rotated 90 ° from fig. 18.

Fig. 20 shows a view of a conventional example.

Description of reference numerals and symbols

10, 40, 50, 70 induction type synchronous motor

11, 15, 51, 72, 92 excitation stator

12, 14, 41, 44, 60, 73, 91 rotor

13, 71 armature stator

17, 23, 30, 76, 79 vacuum insulation shell

18, 31, 78, 93 field coil

20, 28, 62, 81, 98N pole inductor

21, 27, 63, 82, 97S pole inductor

24, 7 armature coil

34, 101 rotating shaft

35, 36, 35 ', 36', 37, 38, 37 ', 38' permanent magnet

95 fixed shaft

99, 100 support part

Detailed Description

Embodiments of the present invention will be described with reference to the accompanying drawings.

Fig. 1 shows an induction type synchronous motor (induction type synchronous machine) 10 according to a first embodiment.

The induction type synchronous machine 10 has an axial air gap structure in which a rotating shaft 34 penetrates sequentially through a field stator 11, a rotor 12, an armature stator 13, a rotor 14, and a field stator 15. The field stators 11, 15 and the armature stator 13 are fixed to the mounting surface G with an air gap provided with respect to the rotating shaft 34, and the rotors 12, 14 are assembled and fixed to the rotating shaft 34 by providing an air gap from the rotating shaft 34 to the rotors 12, 14.

Excitation stator 11 and excitation stator 15 are bilaterally symmetrical with respect to the map. Thus, fig. 3(a) and 3(B) schematically show one of the stators 15.

Each excitation stator 11, 15 has a yoke 16, 29 made of a magnetic material and fixed to the mounting surface G; heat-insulating refrigerant containers 17, 30 having a vacuum-insulating structure embedded in the respective yokes 16, 29, and excitation coils 18, 31, which are windings made of a superconducting material, and are accommodated in the respective heat-insulating refrigerant containers 17, 30.

Each yoke 16, 29 has a loose fitting hole 16b, 29b in which a hole is bored in a central portion thereof so as to have a diameter larger than the outer diameter of the rotation shaft 34, and a groove portion 16a, 29a concavely configured in an annular shape around the loose fitting hole 16b, 29 b. Each excitation coil 18, 31 is housed in a respective insulated cryogen vessel 17, 30, inside which insulated cryogen vessel 17, 30 liquid nitrogen circulates. Each insulated cryogen vessel 17, 30 is embedded in a respective recess portion 16a, 29 a.

The yokes 16, 29 are made of a magnetic material such as permendur, silicon steel sheet, iron, and permalloy. As the superconducting material for forming the field coil 18, 31, a bismuth-based or yttrium-based high-temperature superconducting material may be suitably used.

The rotors 12, 14 are bilaterally symmetrical. Thus, fig. 2(a) to 2(D) schematically show one of the rotors 14.

Each rotor 12, 14 includes a disc-shaped support portion 19, 26 made of a non-magnetic material, and has a rotation axis mounting hole 19a, 26a, a S-pole inductor pair 21, 27 embedded at a point-symmetrical position around the rotation axis mounting hole 19a, 26a, and an N-pole inductor pair 20, 28 embedded at a position rotated 90 ° from the position of the corresponding S-pole inductor 21, 27.

The S-pole inductors 21, 27 and the N-pole inductors 20, 28 are configured such that the respective fan-shaped end faces 20a, 21a, 27a, 28a facing the armature stator 13 are disposed at equal intervals along the concentric circles, and such that the areas of the end faces 20a, 21a, 27a, 28a are equal to each other.

The other end face 21b, 27b of the S-pole inductor 21, 27 is arranged to face the S-pole generating position of the exciting coil 18, 31. For example, as shown in fig. 2(C) and 4(B), the other end face 27B of the S-pole inductor 27 has a circular arc shape and is arranged to face the outer circumferential side of the exciting coil 31.

The other end faces 20b, 28b of the N-pole inductors 20, 28 are arranged to face the N-pole generating positions of the exciting coils 18, 31. For example, as shown in fig. 2(C) and 4(C), the other end face 27b of the S-pole inductor 27 has a circular arc shape and is arranged to face the inner circumferential side of the exciting coil 31.

That is, each of the S-pole inductors 21, 27 and the N-pole inductors 20, 28 has a three-dimensional shape whose cross-sectional shape changes along the axial direction from the circular-arc shape on the other end face 20b, 21b, 27b, 28b to the fan shape on the end face 20a, 21a, 27a, 28 a. The cross-sectional area of each of the S-pole inductors 21, 27 and the N-pole inductors 20, 28 from the other end face 20b, 21b, 25b, 28b to the end face 20a, 21a, 25a, 28a is constant. Further, the area of each of the other end faces 20b, 28b of the S-pole inductors 20, 28 is the same as the area of each of the other end faces 21b, 27b of the N-pole inductors 21, 27.

The support portion 26 is formed of a nonmagnetic material such as FRP and stainless steel. The inductors 27, 28 are made of magnetic material, such as permendur, silicon steel sheet, iron, and permalloy.

As shown in fig. 1(a) and 1(B), the armature stator 13 includes: a support portion 22 formed of a non-magnetic material and fixed to the mounting surface G, a heat-insulating refrigerant container 23 having a vacuum-insulating structure and embedded in the support portion 22, and armature coils 24, each of which is a winding made of a superconducting material and is accommodated in the heat-insulating refrigerant container 23.

The support portion 22 has a loose fitting hole 22b bored at a central portion of the support portion 22 so as to have a diameter larger than the outer diameter of the rotation shaft 34, and four mounting holes 22a bored and disposed at equal intervals in a circumferential direction around the loose fitting hole 22 b. Each armature coil 24 is accommodated in an insulating refrigerant container 23, liquid nitrogen circulates in the insulating refrigerant container 23, and a magnetic flux collector 25 formed of a magnet is disposed in a hollow portion of each armature coil 24. Four heat-insulating refrigerant containers 23 respectively accommodating armature coils 24 are inserted in the coil mounting holes 22 a.

The flux collector 25 is made of a magnetic material such as permendur, silicon steel sheet, iron, and permalloy. As the superconducting material forming the armature coil 24, a bismuth-based or yttrium-based high-temperature superconducting material may be suitably used. The support portion 22 is formed of a nonmagnetic material, such as FRP and stainless steel.

The power feeding device 32 is connected to the exciting coils 18, 31 and the armature coil 24 by wires, and supplies a direct current to the exciting coils 18, 31 while supplying a three-phase alternating current to the armature coil 24.

The liquid nitrogen tank 33 is connected to the insulated cryogen vessels 17, 23, 30 by insulated piping, and circulates liquid nitrogen as a coolant.

Next, the operation principle of the induction type synchronous motor 10 will be described. When a direct current is supplied to the exciting coil 31 on the right side in fig. 1, an S pole is generated on the outer circumferential side of the exciting coil 31, while an N pole is generated on the inner circumferential side thereof. Subsequently, as shown in fig. 4(a) and 4(B), the magnetic flux on the S-pole side is introduced into the S-pole inductor 27 from the other end face 27B, whereby the S-pole magnetic flux appears on the end face 27 a. Further, as shown in fig. 4(a) and 4(C), the magnetic flux on the N-pole side is introduced into the N-pole inductor 28 from the other end face 28b, whereby the N-pole magnetic flux appears on the end face 28 a. Since the other end faces 27b, 28b are provided concentrically along the outer circumference and the inner circumference of the exciting coil 31, respectively, S-pole magnetic flux always appears on the end face 27a of the S-pole inductor, and N-pole always appears on the end face 28a of the N-pole inductor 28.

Based on a similar principle, when a direct current is supplied to the exciting coil 18 on the left side in fig. 1, the N pole always appears on the end face 20a of the N pole inductor 20 of the rotor 12, and the S pole always appears on the end face 21a of the S pole inductor 21.

When three-phase alternating current is supplied to the armature coil 24 in this state, a rotating magnetic field 18 is generated around the axis of the armature stator 13 due to the phase shift of power feeding among the three phases. Due to the rotating magnetic field, a torque is generated around each shaft of the N-pole inductors 20, 28 and the S-pole inductors 21, 27 of the rotors 12, 14, whereby the rotors 12, 14 rotate to rotationally drive the rotating shaft 34.

According to the above configuration, the field stators 11, 15 to which the field coils 18, 31 are connected, and the armature stators to which the armature coils 24 are connected do not rotate, and the rotors 12, 14 to which the inductors 20, 21, 27, 28 are connected, rotate together with the rotating shaft 34. Therefore, it is no longer necessary to use a sliding contact member such as a slip ring for feeding electric power to the respective coils 18, 31, whereby simplification of the power feeding structure and stabilization of the power feeding can be achieved, and a longer life of the motor is facilitated. Further, the insulated cryogen vessel 17, 23, 30, to which liquid nitrogen is supplied from a liquid nitrogen tank 33, is fixed and does not move when the motor is in operation. Therefore, the design of the coolant supply path and the seal structure becomes easier, whereby simplification of the cooling structure can be achieved.

Further, since the exciting coils 18, 31 and the armature coil 24 are formed of a superconducting material, a large current can be supplied to sharply increase the magnetic flux. Accordingly, even when flux leakage occurs such that the flux deviates in an undesired direction, the flux beneficial to the output can be increased, and thus, a high power output can be achieved.

Further, since the cross-sectional area of each of the N-pole inductors 20, 28 and the S-pole inductors 21, 27 from the other end face 20b, 21b, 27b, 28b to the end face 20a, 21a, 27a, 28a is set to be constant, saturation of magnetic flux in the inductors 20, 21, 27, 28 is suppressed, whereby magnetic flux can be efficiently induced toward the direction of each armature coil 24.

Further, since the cross-sectional area of each of the N-pole inductors 20, 28 and the cross-sectional area of each of the S-pole inductors 21, 27 are substantially equal, the attractive/repulsive force generated between the inductors and the armature coils 24 is constant, whereby the rotational balance of the rotors 12, 14 can be stabilized.

The field coils 18, 31 or the armature coil 24 may be formed of a generally conductive material, such as copper wire. In this case, the cooling structure for the normal conductive line may be omitted. Furthermore, although this embodiment relates to an electric motor, the same structure may be used in a generator.

Fig. 5 to 9 show modifications of the first embodiment. This modification differs from the first embodiment in that the exciting element is a permanent magnet.

In the first modification shown in fig. 5 and 6, each permanent magnet 35, 36 having a U-shaped cross section in the radial direction and a ring shape is connected to the corresponding yoke 16, 29 of the excitation stator 11, 15, thereby causing the N pole and the S pole to be concentrically arranged.

Specifically, the permanent magnet 35 having an S pole on the inner circumferential side and an N pole on the outer circumferential side is attached to an annular groove portion 16a, and the annular groove portion 16a is concavely disposed on the yoke 16 of the excitation stator 11 around the loose fitting hole 16b (left side in fig. 5).

On the other hand, a permanent magnet 36 having an S pole on the inner circumferential side and an N pole on the outer circumferential side is attached to an annular groove portion 29a, and the annular groove portion 29a is concavely disposed on a yoke 29 of the excitation stator 15 around a loose fitting hole 29b (right side in fig. 5).

In the second modification shown in fig. 7, a plurality of permanent magnets 37, 38 divided into fan-like shapes are arranged in the groove portions 16a, 29a, wherein the groove portions 16a, 29a are arranged in the yokes 16, 29 of the excitation stators 11, 15 in the circumferential direction of the excitation stators without spaces between the adjacent magnets, thereby providing the same shape as that of the permanent magnets of the first modification.

In a third modification shown in fig. 8, similarly to the second modification, a plurality of divided permanent magnets 37 ', 38' are arranged in the groove portions 16a, 29a in the circumferential direction of the excitation stator, the groove portions 16a, 29a being arranged in the yokes 16, 29 of the excitation stators 11, 15. However, instead of being divided into fan shapes, the permanent magnets 37 ', 38' are formed so that the width on the outer circumferential side is equal to the width on the inner circumferential side. Therefore, although the permanent magnets 37 ', 38' are arranged without a space between the adjacent magnets on the inner circumferential side, there is an air gap between the adjacent permanent magnets 37 ', 38' on the outer circumferential side.

In the fourth modification shown in fig. 9, the sectional shape in the radial direction of each annular permanent magnet 35 ', 36' is formed in a rectangular shape, which is different from the first to third modifications.

Similarly to the first modification, the permanent magnet 35' is attached to the annular groove portion 16a, and the annular groove portion 16a is concavely configured to surround the loose fitting hole 16b, thereby making the S pole on the inner circumferential side and the N pole on the outer circumferential side. On the other hand, the permanent magnet 36' is attached to the annular groove portion 29a, and the annular groove portion 29a is concavely configured to surround the loose fitting hole 29b, thereby making the S pole on the outer circumferential side and the N pole on the inner circumferential side.

Permanent magnets divided in the circumferential direction may also be used in this modification, similar to the second and third modifications.

In the induction type synchronous motor having the above-described structure, the magnetic flux on the S-pole side of the permanent magnet is introduced into the S-pole inductors 21, 27, thereby causing the S-pole magnetic flux to appear on the end faces 21a, 27a of the S-pole inductors 21, 27. Further, the magnetic flux on the N-pole side of the permanent magnet is introduced into the N-pole inductor 20, 28, thereby causing N-pole magnetic flux to appear on the end faces 20a, 28a of the N-pole inductor 20, 28.

When three-phase alternating current is supplied to the armature coil 24 in this state, a rotating magnetic field is generated around the axis of the armature stator 13 due to the phase shift of power feeding among the three phases. The rotating magnetic field generates a torque around the shaft of each of the N-pole inductors 20, 28 and the S-pole inductors 21, 27 of the rotors 12, 14, whereby the rotors 12, 14 rotate to rotationally drive the rotating shaft 34.

According to the above configuration, since the permanent magnets are arranged at the excitation stators 11, 15, the manufacturing efficiency of the induction type synchronous motor is improved. Further, a power feeding device of the exciting element and a cooling structure are not required, whereby the structure can be simplified.

Further, the output power is from 1kW to 5MW, and therefore it is sufficient to use a permanent magnet as the excitation element. Therefore, compared to the case where a superconducting material is used as the field element as in the first embodiment, an induction type synchronous motor of reduced size can be realized.

Similarly to the present embodiment, a permanent magnet may also be used as the exciting element in the following embodiments.

Fig. 10 shows a second embodiment.

The second embodiment is different from the first embodiment in that the number of rotors 41, 44 and armature stators 13 is increased.

More specifically, the rotor 41, the armature stator 13, the rotor 44, and the armature stator 13 are added between the armature stator 13 and the rotor 14 of the first embodiment.

Each of the rotors 41, 44 includes a disk-shaped made portion 42, 45 made of a non-magnetic material and formed with a rotation shaft mounting hole 42a, 45a for the rotation shaft 34, and the inductor 43, 46 has four magnetic members embedded at equal intervals in the circumferential direction around the rotation shaft mounting hole 42a, 45a, respectively. Each inductor 43, 46 has a sector shape identical to the sector shape of the flux collector 25 of the armature stator 13. The support portions 42, 45 are formed of a nonmagnetic material, such as FRP and stainless steel. The inductors 43, 46 are made of magnetic materials such as permendur, silicon steel sheet, iron, and permalloy.

In the above structure, the exciting coils 18, 31 are formed of a superconducting material, whereby the magnetic flux can be significantly increased to reach a distant position. Therefore, the plurality of rotors 12, 41, 44 can be arranged between the excitation stators 11, 15 on the respective sides, and the output torque can be improved.

Since other structures of the second embodiment are similar to those of the first embodiment, the same reference numerals are given and the description thereof is omitted.

Fig. 11 shows a third embodiment.

The third embodiment differs from the first embodiment in that rotors 12, 14, an armature stator 13, and a field stator 51 are added.

More specifically, the field stator 51, the rotor 12, the armature stator 13, and the rotor 14 are added between the field stator 15 and the rotor 14 of the first embodiment.

The excitation stator 51 includes: a yoke 52 formed of a non-magnetic material and fixed to the mounting surface G, a heat-insulating refrigerant container 54 having a vacuum insulation structure embedded in the yoke 52, and an armature coil 53 which is a winding made of a superconducting member and is accommodated in the heat-insulating refrigerant container 54.

The yoke 52 has a loose fitting hole 52b bored at the center of the yoke 52 such that the outer diameter of the loose fitting hole is larger than that of the rotating shaft 34, and the yoke 52 has a mounting hole 52a bored in a ring shape around the loose fitting hole 52 b. The exciting coil 53 is accommodated in an annular heat-insulating refrigerant container 54, and liquid nitrogen circulates inside the heat-insulating refrigerant container 54. The heat-insulating refrigerant container 54 is fitted into the mounting hole 52 a.

Since the structure of the third embodiment is similar to that of the first embodiment, the same reference numerals are given and the description thereof is omitted.

Fig. 12 shows a fourth embodiment.

The fourth embodiment is different from the first embodiment in that the number of N-pole inductors 62 and S-pole inductors 63 of the rotor 60 is increased.

The rotor 60 has a disc-shaped support portion 61 made of a non-magnetic material, and is formed with a mounting hole 61a for a rotation shaft, and six N-pole inductors 62 and six S-pole inductors 63 alternately arranged at regular intervals in the circumferential direction around the mounting hole 61 a.

The other end surface 62b of the N-pole inductor 62 is arranged to face the outer circumferential side of the exciting coil 31, which is the N-pole generating position. The other end surface 63b of the S-pole inductor 63 is arranged to face the inner circumferential side of the exciting coil 31, which is the S-pole generating position. End faces 62a, 63a of the N-pole inductor 62 and the S-pole inductor 63 facing the armature stator 13 are arranged on a concentric circle at regular intervals. The cross-sectional area of each of the N-pole inductor 62 and the S-pole inductor 63 is constant from the end face 62a, 63a to the other end face 62b, 63 b. Meanwhile, the cross-sectional area of each N-pole inductor 62 and the cross-sectional area of each S-pole inductor 63 are substantially equal.

Since other structures are similar to those of the first embodiment, the description thereof is omitted.

Fig. 13 to 16 show a fifth embodiment.

The fifth embodiment is different from the first embodiment in that it relates to an induction type synchronous motor 70 of a radial air gap structure.

The armature stator 71 includes a yoke 74 formed of a magnetic material and having four tooth portions 74b protruding from an inner circumferential surface of the cylindrical portion 74a at regular intervals in a circumferential direction, annular heat-insulating refrigerant containers 76 each having a vacuum-insulating structure and surrounding each tooth portion 74b, and armature coils 75 each being a winding made of a superconducting material and accommodated in the corresponding heat-insulating refrigerant container 76.

The excitation stator 72 is fitted and fixed to the yoke 74 of the armature stator 71, and includes a disc-shaped yoke 77 formed of a magnet; a heat-insulating refrigerant container 79 having a vacuum-insulating structure and embedded in the yoke 77, and an excitation coil 78 which is a winding made of a superconducting material and is accommodated in the heat-insulating refrigerant container 79. The yoke 77 has a loose fitting hole 77a in which a hole is bored at a central portion thereof to thereby have an outer diameter larger than that of the rotation shaft 84, and a groove portion 77b concavely configured in an annular shape around the loose fitting hole 77 a. The exciting coil 78 is accommodated in a heat-insulating refrigerant container 79, and liquid nitrogen is circulated in the heat-insulating refrigerant container 79. The heat-insulating refrigerant container 79 is embedded in the groove portion 77 b.

The rotor 73 includes: a disc-shaped supporting portion 80 made of a non-magnetic material, and having a mounting hole 80a through which a rotating shaft 84 is mounted; a pair of N-pole inductors 81 embedded at point-symmetric positions around the mounting hole 80 a; and a pair of S-pole inductors 82 embedded at positions rotated by 90 ° from the position of the N-pole inductor 81.

As shown in fig. 14 and 16, each N-pole inductor 81 has a multi-stage belt-like shape, and one end 81a is configured to face and follow the N-pole generating position of the excitation coil 78 while an outer surface 81b on the other end side is configured to face the armature coil 75.

As shown in fig. 15 and 16, each S-pole inductor 82 has a shape of a folded-back strip, and one end 82a is arranged to face and follow the S-pole generating position of the exciting coil 78 while an outer surface 82b on the other end side is arranged to face the armature coil 75. The other end 82c of the S-pole inductor 82 does not extend to the end face of the rotor 73, but the S-pole inductor 82 is formed in a folded-back shape, thereby spacing it from the N-pole of the excitation coil 78, making it difficult for magnetic flux leakage to occur.

The cross-sectional area of each of the N-pole inductor 81 and the S-pole inductor 82 is constant, and the cross-sectional areas thereof are substantially equal to each other.

The yokes 74, 77, the N-pole inductor 81, and the S-pole inductor 82 are formed of a magnetic material such as permendur, silicon steel sheet, iron, and permalloy. The support portion 80 is formed of a nonmagnetic material, such as FRP and stainless steel.

The power feeding device 32 is connected to the exciting coil 78 and the armature coil 75 by wires. A direct current is supplied to the exciting coil 78, and a three-phase alternating current is supplied to the armature coil 75 at the same time.

The liquid nitrogen tank 33 is connected to insulated cryogen vessels 76, 79 by insulated piping. Thereby circulating liquid nitrogen as a coolant.

Next, the operation principle of the induction type synchronous motor 70 will be described below.

When a direct current is supplied to the exciting coil 78, an N-pole is generated on the outer circumferential side of the exciting coil 78, while an S-pole is generated on the inner circumferential side thereof. Subsequently, as shown in fig. 14, the magnetic flux on the N-pole side is introduced into the N-pole inductor 81 from the other end face 81a, whereby the N-pole magnetic flux appears on the outer surface 81b on the other end side. Further, as shown in fig. 15, the magnetic flux on the S-pole side is introduced into the S-pole inductor 82 from the other end surface 82a, whereby the S-pole magnetic flux appears on the outer surface 82b on the other side.

When a three-phase alternating current is supplied to the armature coil 75 in this state, a rotating magnetic field is generated on the inner circumferential surface around the axis of the armature stator 71 due to the power feeding phase shift. The rotating magnetic field causes a torque to be generated on the N-pole inductor 81 and the S-pole inductor 82 about the axis. Thereby, the rotor 73 is rotated to rotationally drive the rotary shaft 84.

Fig. 17 shows a sixth embodiment.

The sixth embodiment differs from the fifth embodiment in that the sixth embodiment has a structure in which the cylindrical excitation stator 90 is surrounded by a substantially tubular rotor 91 with an air gap disposed therebetween.

Since the armature stator 71 is similar to that of the fifth embodiment, the description thereof is omitted.

The excitation stator 90 has a cylindrical yoke 92 formed of a magnet, an annular vacuum insulation case 94 fitted and fixed to an outer circumference of the yoke 92, an excitation coil 93 formed of a superconducting material, accommodated in the heat-insulating refrigerant container 94 and wound around a shaft, and a fixed shaft 95 laterally protruding from a center of one of end faces of the yoke 92.

The rotor 91 includes an S-pole inductor 97 formed of a magnetic material, having a U-shaped cross section, and disposed to cover a left side portion of the excitation stator 90 at a position rotated by 90 °; an N-pole inductor 98 formed of a magnetic material, which has a U-shaped cross section and is disposed so as to cover a right side portion of the excitation stator 90, support portions 99, 100 formed of a non-magnetic material and connecting the S-pole inductor 97 and the N-pole inductor 98 as one body, and a rotation shaft 101 projecting laterally from the center of a right side end face of the rotor 91.

As shown in fig. 18, the S-pole inductor 97 is configured such that the left-side end face 97a faces the S-pole generating position of the exciting coil 93, and thereby the outer circumferential surface 97b faces the armature coil 75 of the armature stator 71. A loose fitting hole 97c having a diameter larger than that of the fixed shaft 95 is bored at the center of the left end face 97 a.

As shown in fig. 19, the N-pole inductor 98 is configured such that the right-side end face 98a faces the N-pole generating position of the exciting coil 93, and thereby the outer circumferential surface 98b faces the armature coil 75. The rotation shaft 101 is fixed to the center of the right side end face 98 a.

According to the above structure, the N poles and the S poles alternately appear on the outer circumferential surface of the rotor 91 in the circumferential direction. The cross-sectional area of each of the S-pole inductor 97 and the N-pole inductor 98 is constant, and the cross-sectional areas of the S-pole inductor 97 and the N-pole inductor 98 are substantially equal to each other.

The yoke 92, the S-pole inductor 97, and the N-pole inductor 98 are formed of a magnetic material such as permendur, silicon steel sheet, iron, and permalloy. The support portions 99, 100 are formed of a non-magnetic material, such as FRP and stainless steel.

Next, the operation principle will be described below.

When a direct current is supplied to the exciting coil 93, an N pole is generated on the right side and an S pole is generated on the left side as shown in the drawing. Subsequently, as shown in fig. 18, magnetic flux on the S-pole side is introduced into the S-pole inductor 97 from the left-side end face 97a, whereby S-pole magnetic flux appears on the outer circumferential surface 97 b. Further, as shown in fig. 19, the magnetic flux on the N-pole side is introduced into the N-pole inductor 98 from the right-side end face 98a, whereby the N-pole magnetic flux appears on the outer circumferential surface 98 b.

When a three-phase alternating current is supplied to the armature coil 75 (not shown) in this state, a rotating magnetic field is generated on the inner circumferential surface around the axis of the armature stator 71 due to the power feeding phase shift. The rotating magnetic field causes a torque to be generated on the N-pole inductor 98 and the S-pole inductor 97 about the shaft. Thereby, the rotor 91 is rotated to rotationally drive the rotary shaft 101.

Claims (8)

1. An induction type synchronous machine comprising:

an excitation stator having an excitation element by which an N pole and an S pole are concentrically formed;

a rotor to which a rotation shaft is fixed and which has an N-pole inductor formed of a magnetic material and configured to face an N-pole of an excitation element, and an S-pole inductor formed of a magnetic material and configured to face an S-pole of the excitation element; and

an armature stator having an armature coil configured to face the N-pole inductor and the S-pole inductor.

2. The induction type synchronous motor according to claim 1, wherein the exciting element includes an exciting coil wound around the rotating shaft,

wherein the partial N-pole inductor is disposed to face one of an outer circumferential side and an inner circumferential side of the exciting coil, and the partial S-inductor is disposed to face the other.

3. The induction type synchronous motor according to claim 1, wherein the exciting element comprises a permanent magnet disposed around the rotation axis,

wherein a part of the N-pole inductor is configured to face an N-pole side of the permanent magnet, and a part of the S-inductor is configured to face an S-pole side of the permanent magnet.

4. The induction type synchronous machine according to any one of claims 1 to 3, wherein at least one of the field element and the armature coil is formed of a superconducting material.

5. The induction type synchronous motor according to any one of claims 1 to 3, wherein a cross-sectional area of each of the N-pole inductor and the S-pole inductor from one end to the other end is constant.

6. The induction-type synchronous electric machine of claim 5 wherein the cross-sectional area of the N-pole inductor is substantially equal to the cross-sectional area of the S-pole inductor.

7. Induction synchronous machine according to any of claims 1 to 3, wherein the induction synchronous machine has an axial air gap structure,

wherein the exciting stator is configured to face one side of the rotor in an axial direction of the rotor with a predetermined air gap therebetween, and the armature stator is configured to face the other side of the rotor in the axial direction of the rotor with a predetermined air gap therebetween,

a rotating shaft fixed to the rotor rotatably passes through and bridges between the field stator and the armature stator, an

The magnetic flux direction of each of the field element and the armature coil is oriented in the axial direction.

8. The induction type synchronous machine according to any one of claims 1 to 3, wherein the induction type synchronous machine has a radial air gap structure in which one of a field stator and an armature stator is a cylindrical tube, and a rotor is disposed within the cylindrical tube with a predetermined air gap between the rotor and the stator.