JPH0739096A - Flat induction machine - Google Patents

Abstract

(57) [Summary] [Purpose] High output per unit weight is possible, ultra-thin and ultra-miniaturized, and it can be applied as a power source for micromachines. [Structure] At least a pair of coil patterns, which are formed on a thin film substrate so that the winding directions are opposite to each other and are connected in series or in parallel, are 2π / n (n is an integer of 2 or more) in terms of a spatial angle converted into an electrical angle It is characterized in that it is provided with a flat plate-shaped stator arranged at different positions, and a flat plate-shaped rotor arranged facing one side or both sides of the stator.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat induction machine having a stator formed by a coil pattern formed on a film-like thin film substrate.

[0002]

2. Description of the Related Art Motors that utilize the attraction and repulsion of magnetic poles are roughly classified into DC machines and AC machines. DC motors can be easily controlled by changing the applied voltage.Therefore, there are DC separately excited motors used for precision servos, etc., and DC series wound motors used for electric trains because they have a strong starting torque. The thing is a DC machine in principle. Since a DC machine has a complicated armature structure, it is relatively expensive, and it is difficult to miniaturize it as a power source for micromachines and other ultra-small equipment. On the other hand, AC motors are typically represented by a step motor, which is a kind of synchronous machine that can perform position control and the like in an open loop, and an induction motor, which has a simple structure, is robust, and is inexpensive to manufacture. The step motor is mainly used for control because it is difficult to increase its capacity, while the induction motor can easily perform speed control with the progress of power electronics. Most of the trains, elevators, escalators, etc. that they occupied are being replaced by induction motors. In fact, the early Tokaido Shinkansen were all DC series motors, but the latest "Nozomi" and others were all inverter-controlled by induction motors.

[0003]

By the way, in the conventional induction machine, in order to reduce the magnetic resistance of the magnetic path as much as possible, a yoke made of silicon steel is used for the stator, and the size of the apparatus becomes large. However, there is a problem that the weight becomes large and the cost becomes high. The present invention is for solving the above-mentioned problems, it is possible to increase the output per unit weight, it is possible to achieve ultra-thin, ultra-miniaturized,
An object of the present invention is to provide a flat induction machine applicable as a power source for a micromachine or the like.

[0004]

A flat induction machine according to the present invention is formed on a thin film substrate so that the winding directions are opposite to each other.
At least a pair of coil patterns connected in series or in parallel are arranged at different positions by 2π / n (n is an integer of 2 or more) in space angle converted into an electrical angle, and a flat plate-shaped stator facing the stator. And a flat plate-shaped rotor arranged on one side or both sides. Further, the present invention is
The rotor is characterized by being lump-shaped or lump-shaped hollowed-out, cage-shaped or cage-shaped hollowed-out, and cage-shaped oblique groove. Further, the flat plate-shaped stator and the flat plate-shaped rotor of the present invention are characterized in that they are cylindrical or cone-shaped in which a flat plate is bent into an annular shape, and are cage-shaped or cage-shaped oblique grooves. Further, according to the present invention, at least a pair of coil patterns, which are formed on the thin film substrate so that the winding directions are opposite to each other and are connected in series or in parallel, are a space angle converted into an electrical angle of 2π / n (n is 2 or more). It is characterized in that a disc-shaped stator arranged at different positions and a rotor arranged so as to surround the disc-shaped stator are equipped with tires. Further, according to the present invention, at least a pair of coil patterns, which are formed on the thin film substrate so that the winding directions are opposite to each other and are connected in series or in parallel, are a space angle converted into an electrical angle of 2π / n (n is 2 or more). A primary coil fixed to the vehicle body and arranged along the vertical direction, and a secondary coil on the line side opposite to the primary coil to generate a moving magnetic field by the primary coil. It is characterized in that the side secondary coil and the magnetic flux are linked to propel the vehicle body.

[0005]

According to the present invention, a coil pattern is formed on a film type substrate to form a stator winding and a rotor winding, and the rotor winding is arranged on both sides of the stator winding. Since the stator winding and rotor winding are flat, the facing area between the stator and rotor is increased to increase the cross-sectional area of the magnetic path and the gap between the stator and rotor is reduced. Since the magnetic path length can be shortened, magnetic resistance can be reduced without using yokes, ultra-thin and miniaturized, and high output per unit weight is achieved. Is possible. Therefore, it is possible to realize an induction machine that is extremely promising as a power source for future micromachines.

[0006]

The present invention is applicable to all induction machines of single-phase to multi-phase alternating current, but three-phase alternating current will be taken as a concrete example below, and an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating a stator used in the flat induction machine of the present invention. In the figure, 10 is a stator, 11 and 12 are coils, 11a, 11b, 12a and 12b are terminals, and 13 is a connecting wire.

FIG. 1 (a) shows a coil corresponding to the stator 1, which is formed on a flat insulating substrate by using a fine processing technique such as a printing technique or a lithograph, and is miniaturized and ultrathin. Is possible. The stator 10 is a pair of coils 1
1, 12 and the coil 11 has terminals 11a, 1
The coil 12 is composed of two wires connected in parallel and wound in a counterclockwise direction starting from winding 1b.
It consists of two parallel-connected wires that are wound clockwise with b being the end of winding, and these are connected in series by a connection wire 13. Since the winding directions of the coils 11 and 12 are opposite to each other, when the stator is energized, one coil forms an N pole and the other coil forms an S pole as shown in FIG. 1B. Therefore, the rotating magnetic field can be formed by arranging the stator shown in FIG. 1A on the disc while converting it into an electrical angle and shifting it by 2 / 3π in terms of the spatial angle, and energizing the stator.

Since this stator does not use a yoke, the magnetic fields generated on both sides of the stator can be utilized, and a rotating magnetic field rotating in the same direction is generated on both sides of the flat disk-shaped stator. . In order to use the rotating magnetic fields on both sides, the rotor is arranged so that the stator is sandwiched between sandwiches, and the yoke of the conventional stator is replaced with the rotor.
For example, as shown in FIG. 2, if rotors 21 and 22 made of a magnetic material or a non-magnetic metal are attached to the shaft 20 on both sides of the stator 10, the rotors 21 and 22 can be driven to rotate. it can. In this induction machine, since the stator has no iron core, stator iron loss does not occur, and all iron loss in the rotor is reduced to output torque. That is, the hysteresis loss acts as the torque of the hysteresis motor, and the eddy current loss acts as the torque of the induction motor. In addition, since there is no yoke on both the stator and rotor, weight can be reduced, and high frequency operation is possible because iron loss does not exist, increasing the output per unit weight compared to conventional induction machines. Is also possible. Further, as described above, since the stator has a flat shape, the facing area between the stator and the rotor is increased to increase the cross-sectional area of the magnetic path and the gap between the stator and the rotor is decreased. Since the magnetic path length can be shortened, the magnetic resistance can be reduced and the magnetic field strength can be increased without using a yoke, and a sufficient rotational driving force can be obtained.

Next, the output torque obtained by the induction machine of the present invention will be described. By the symmetric coordinate method, the circuit equation for the positive phase component is Can be written. Where E is the stator phase voltage, I ₁ is the stator current, I ₂ is the rotor current, R ₁ is the stator resistance, R ₂ is the rotor resistance, X ₁ is the stator reactance and X ₂ is Rotor reactance, s is slip, and j is (-1) ^1/2 .
The slip s in the equation (1) is defined by s = (ω-ω _m ) / ω, (2). Where ω is the frequency of the exciting current and ω _m is the mechanical angular velocity.

The transformation matrix A is defined as follows. The equation (1) is converted into the following equation. Alternatively, by multiplying the second column by 1 / a ² , Here, when a = R ^1/2 , the equation (4) is Becomes Here, if s≈0 and I ₂ ′ ≈0 are set in the no-load condition, that is, in the equation (5), the resistance R ₁ and the reactance X ₁ are R ₁ = P ₀ / 3I ₁ ² X ₁ = { (E / I ₁ ) ² −R ₁₂ ² } ^1/2 (6) where P ₀ is the total input when there is no load. When the lock condition, that is, s = 1 in the equation (5), the following relationship is obtained.

[0011] _{α 1 = P 1 / (3I} 1 2) -R 1 = {X m 2 / R 2} / {1+ (X 2 / R 2) 2} α 2 = X 1 - {(E / I 1 ) ²⁻ (α ₁ + R ₁ )} ^1/2 = {X _m ² · X ₂ / R ₂ ² } / {1+ (X ₂ / R ₂ ) ² } ... (7) Here, P ₁ is locked. It is the total input energy in the condition. From the equation (7), the other parameters of the equation (5) are obtained by the following equation.

X ₂ / R ₂ = α ₂ / α ₁ X _m / R ₂ ^1/2 = [α ₁ {1+ (α ₂ / α ₁ ) ² }] ^1/2 (8) If the mechanical output is P _m and the torque is T _m , then P _m = 3 {(1-s) / s} I _2s ′ ² [W] T _m = 3 {(p / sω)} I _2s ′ ² [N−m] (9) where p is the number of magnetic pole pairs, and I _2s ′ is the rotor current at the time of slip s.

FIG. 3 shows the experimental value and the calculated value of the torque versus the rotational speed obtained by measuring the total input energy and the stator current at a certain slip s. As can be seen from FIG. 3, it can be seen that the experimental value that substantially matches the calculated value obtained by the equation (9) is obtained.

FIG. 4 is a diagram showing an example of a rotor used in the present invention. As described above, the material of the rotor used in the present invention may be either magnetic substance or non-magnetic substance metal.
In (a), the rotor 30 is a flat massive disk, and by arranging the rotor 30 so as to face the above-mentioned stator, a rotating torque is generated by the rotating magnetic field generated in the stator.
FIG. 4 (b) shows a rotor 31 in which the central portion of the massive disc of FIG. 4 (a) is hollowed out to form a hole 31a. By doing so, the interlinking magnetic flux can be collected in the peripheral portion of the disk to increase the rotating torque.

FIG. 4 (c) shows a cage rotor 32 in which slits 32a are radially formed on a flat disc.
The slit 32 controls the path of the eddy current to appropriately change the impedance and obtain a desired torque. FIG. 4 (d) shows a rotor 33 in which slits 33a are radially formed and a hole 33b is formed by hollowing out the central portion, and the contribution to the rotational torque is the same as in FIG. 4 (b). The small central part is hollowed out to increase the rotational torque. Fig. 4 (e) shows a cage-shaped rotor with slits formed as diagonal grooves, and Fig. 4 (f) shows the one shown in Fig. 4 (e) further hollowed out. The change of the magnetic field can be smoothed to reduce the influence of spatial harmonics, and smooth rotation can be obtained.

As described above, the rotor may be a simple coin-shaped disc (so-called Solid Rotor), and a type in which slits are radially provided from the center of the disc to control the current path and electric resistance of the rotor (so-called solid rotor). It may be a basket-type rotor), and the structure of the rotor is extremely simple, and it is possible to easily miniaturize it. Further, the rotor having the slits radially provided from the center of the disk can be easily miniaturized by using a printing technique or a fine processing technique such as a lithograph like the stator. Further, the rotor does not necessarily have to cover the entire stator, and for a stator coil having a hollow central portion, the rotor may have a hollow structure in which only the stator coil portion is covered. Therefore, if a fan or the like is attached to the hollow portion of the rotor, an extremely thin ventilation fan or the like can be realized. Further, as one method of increasing the output, a method of alternately sandwiching three rotors between two stator coils is also possible.

As shown in FIG. 5, a three-phase alternating current is applied to U, V, and W-phase coils that generate a moving magnetic field by the same principle as a multiphase linear motor to generate a moving magnetic field, and mercury, liquid sodium, seawater, etc. are generated. When it is directly immersed in the liquid having electrical conductivity, the fluid having electrical conductivity flows. Therefore, unlike the conventional electromagnetic pump, a magnetic path formed of a magnetic material is not required outside, and heat generated in the coil due to copper loss is also cooled by the fluid. Further, since there is no air gap between the exciting coil and the fluid, the leakage magnetic flux and the exciting current are extremely small, and since there is no iron loss, a highly efficient electromagnetic pump can be realized.

FIG. 6 shows an example of such an electromagnetic pump, in which a moving magnetic field generating coil 41 shown in FIG. 5 is provided in a conductive fluid in a tube 40, and a three-phase alternating current is supplied to generate a moving magnetic field. Once generated, the conductive fluid flows in the direction indicated by arrow 42 and can operate as an electromagnetic pump.

FIG. 7 shows an example of an electromagnetic induction ship using an electromagnetic pump. The coil of FIG. 5 is attached to the portion of the hull 50 in contact with seawater, and a three-phase alternating current is applied to the coil to generate a moving magnetic field 52. By the interaction between the eddy current generated in seawater and the magnetic field generated by the coil, the hull can be propelled in the direction opposite to the direction of the moving magnetic field generated by the coil (the direction of arrow 53).

FIG. 8 shows an example applied to an electric motor for an electric vehicle. A stator 60 in which a disk-shaped coil is arranged on a shaft 62 is formed, and a conductor disk serving as a rotor is installed around the stator to outrow. It is possible to realize a ta-type induction motor, and this rotor can be used as an electric motor for a four-wheel drive electric vehicle if tires are mounted as wheels of the vehicle.

Further, as shown in FIG. 9, a linear motor car can be realized by arranging a plurality of the coils shown in FIG. 5 vertically as a primary coil 71 and making them face a line 72 as a secondary coil. In the configuration of FIG. 9, the primary coil 7
Since the magnetic field produced by No. 1 is in the lateral direction, there is no magnetic field penetration into the vehicle, and it is possible to diminish the magnetic induction obstacle.

In the above embodiment, both the stator and the rotation are explained as flat plates, but the flat induction machine of the present invention does not necessarily have to be flat plates. For example, as shown in FIG. 10, a flat plate-shaped stator is bent into an annular shape to form a cylindrical stator 80, which is inserted between an inner rotor 81 and an outer rotor 82 which are also formed in a cylindrical shape. To do. It should be noted that the rotors 81 and 82 may be either separate members or integrated members.

As shown in FIG. 11, the stator 90,
The inner rotor 91 and the outer side 92 may be formed in a cone shape. In the case of both the cylindrical rotor and the cone rotor, slits may be formed for impedance control and reduction of the influence of spatial harmonics, as in the case of FIG.

[0024]

As described above, according to the present invention, the stator,
Since there is no yoke part that passes magnetic flux in both rotors, weight reduction is possible, and since no yoke is used, the magnetic fields generated on both sides of the stator can be used, and since the stator does not have an iron core, the stator No iron loss occurs, and all iron loss in the rotor is reduced to output torque. Moreover, since there is no yoke in the stator and the rotor, there is no iron loss, high frequency operation is possible, and output per unit weight can be increased as compared with the conventional induction machine. Also, since the stator is flat, the facing area between the stator and rotor is increased to increase the cross-sectional area of the magnetic path, and the gap between the stator and rotor is decreased to shorten the magnetic path length. Therefore, the magnetic resistance can be reduced and the magnetic field strength can be increased without using a yoke, and a sufficient rotational driving force can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a stator of a flat induction machine according to the present invention.

FIG. 2 is a diagram illustrating a flat induction machine.

FIG. 3 is a diagram illustrating torque of a flat induction machine.

FIG. 4 is a diagram illustrating a rotor used in a flat induction machine.

FIG. 5 is a diagram illustrating a moving magnetic field generating coil.

FIG. 6 is a diagram illustrating an electromagnetic pump.

FIG. 7 is a diagram illustrating an electromagnetic induction ship.

FIG. 8 is a diagram illustrating an electric motor for an electric vehicle.

FIG. 9 is a diagram illustrating an example of a linear motor car.

FIG. 10 is a diagram illustrating a tubular induction machine.

FIG. 11 is a diagram illustrating a cone type induction machine.

[Explanation of symbols]

10 ... Stator, 11, 12 ... Coil, 11a, 11b,
12a, 12b ... Terminal, 13 ... Connection line, 20 ... Shaft, 2
1, 22 ... Rotor, 30, 31, 32, 33, 34, 3
5 ... Rotor, 32a, 33a, 34a, 35a ... Slit.

Claims (9)

[Claims] 1. A spatial angle converted into an electrical angle of at least a pair of coil patterns which are formed on a thin film substrate and whose winding directions are opposite to each other and which are connected in series or in parallel, and have a spatial angle of 2π / n.
(N is an integer of 2 or more) A flat induction machine provided with flat plate-shaped stators arranged at different positions and flat plate-shaped rotors facing the stator on one side or both sides thereof. 2. The flat induction machine according to claim 1, wherein the rotor is a block or a block and is hollowed out. 3. The flat induction machine according to claim 1, wherein the rotor has a cage shape having radial slits or is hollowed out in a cage shape. 4. The flat induction machine according to claim 3, wherein the cage rotor has slits formed by oblique grooves. 5. The flat induction machine according to claim 1, wherein the flat plate-shaped stator and the flat plate-shaped rotor are cylindrical or cone-shaped in which a flat plate is bent into an annular shape. 6. The flat induction machine according to claim 5, wherein the rotor has a cage shape with slits formed therein. 7. The flat induction machine according to claim 6, wherein the cage rotor has slits formed by oblique grooves. 8. A spatial angle converted into an electrical angle of at least a pair of coil patterns which are formed on a thin film substrate so that the winding directions are reversed and are connected in series or in parallel, and the spatial angle is 2π / n.
(N is an integer of 2 or more) each having a disk-shaped stator arranged at different positions and a rotor arranged so as to surround the disk-shaped stator, and a tire is mounted on the rotor. Flat induction machine. 9. A spatial angle converted into an electrical angle of at least a pair of coil patterns, which are formed on a thin film substrate so that the winding directions are reversed and are connected in series or in parallel, and have a spatial angle of 2π / n.
(N is an integer greater than or equal to 2) The primary coil fixed to the vehicle body is arranged along the vertical direction, and the line side secondary coil is arranged to face the primary coil. Is generated, and the magnetic flux is interlinked with the secondary coil on the line side to propel the vehicle body.