JPH02193553A - Ac rotary machine - Google Patents

Abstract

PURPOSE:To improve the efficiency of an AC rotary machine by a method wherein an armature coil is fitted so as to wind one piece of armature tooth and four pieces of permanent magnets, whose number is larger than the number of phase 3 of a 3-phase AC by one, are arranged in the spaces of respective phases while converting the polarities thereof to form field magnets. CONSTITUTION:Armature coils 24, forming an armature 20 having three phases U-W, are fitted into slots 22a so as to wind one of armature teeth 22b formed on the inner peripheral surface of an armature core 22. A plurality of permanent magnets 34 is arranged on the outer peripheral surface of a rotor core 32 alternately while converting the polarities alternately to form field magnets. Four pieces of permanent magnets, which means the number of phases of the three- phase AC of a power source plus one, are arranged in every spaces of respective phases of an armature. According to this method, a magnetic field, produced by one set of winding, will never be cancelled by another magnetic field, produced by the other winding, whereby a magnetic resistance between the armature and the field magnet is constituted so as to be small and a rotary machine having a high efficiency can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an AC rotating machine that obtains rotational force by passing an AC current through armature windings arranged in a circular shape.

[Prior Art] Synchronous machines are conventionally known as AC rotating equipment that can provide stable rotational force. -The configuration of a synchronous machine for boat fishing is as follows.

FIG. 5 is a principle explanatory diagram schematically showing the configuration of a rotating field type three-phase synchronous machine 100. As shown in the figure, the armature 102 on the stator side includes an armature coil 108 embedded in a throttle 106 that is continuously formed in the circumferential direction of an annular core 104 with high magnetic permeability. For the armature coil 10 embedded in the slot 106, in the case of a three-phase system, one armature coil is wound over three slots, and the slots at both ends of the armature coil 108 are interlinked. Embedded in 106 are two other armature coils.

For each armature coil 10 days interlinked with each other in this way, it is arranged periodically according to the arrangement order (in Fig. 5, U,
If a current of a predetermined phase of a three-phase alternating current is passed through the three-phase alternating current (with regularity described as V and W phases), a magnetic field that changes spatially in a substantially sinusoidal manner is generated. Further, as is well known, this substantially sinusoidal magnetic pole becomes a so-called rotating magnetic field that moves by an electrical angle of 2π with one cycle of change in the three-phase alternating current supplied to the armature coil 108.

Therefore, the rotor 112 provided in the stator 102 with a predetermined gap 110 has a cylindrical body 114 made of a magnetic material.
A permanent magnet is attached to the circumferential surface of the stator 102 in a manner corresponding to 2'=J to the rotating magnetic field created by the stator 102. In other words, as shown in FIG.
Two permanent magnets 116 are mounted within the spatial angle in which the silk (3) armature coils are wound, with the north and south poles located in the gap 110.

Therefore, in a known synchronous machine, if the number of poles of the field is p, and the frequency of the AC power supply supplied to the armature is f, then the rotation speed n should match the synchronous speed expressed by equation (1). become.

n=120 [rpm
-(1) Therefore, the synchronous machine with the above configuration:
It is widely used especially for applications where stability of rotational speed is desired.

[Problem to be solved by the invention] As mentioned above, the synchronous machine was developed to obtain stable rotation, but due to the following reasons, there are minute irregularities in rotational torque, and so-called cogging occurs. This issue remains.

FIG. 6 is an explanatory diagram of the principle of the rotating magnetic field generated in the gap 110 when three-phase alternating current is passed through the armature coil of the three-phase synchronous machine shown in FIG. It is. This figure shows the magnetic fields generated by the armature coils 108 of each phase independently at a certain moment,
This diagram schematically represents how these combined magnetic fields form a substantially sinusoidal wave.

At the moment shown in the figure, the maximum N-pole magnetic field is generated by the armature coil 108 through which the U-phase alternating current is passed, and its magnitude is halved by the armature coil 108 through which the V-phase and W-phase alternating currents are passed. A magnetic field with an S pole is generated. Further, the spatial position of the generated magnetic field is a spatial portion directly below each armature coil 108 that generates the magnetic field. As described above, the armature coils 108 through which alternating currents of different phases are passed are arranged so as to spatially partially interlink with each other. Therefore, in the magnetic fields generated by each armature coil 108, the magnetic fluxes of the same polarity are added together in the interlinked portions, and the magnetic fluxes of different polarities are canceled out. Therefore, as shown in FIG. 6, the combined magnetic field becomes a substantially sinusoidal magnetic field.

Since the above-mentioned substantially sinusoidal magnetic field becomes a rotating magnetic field that gradually rotates as the phase of the three-phase alternating current passed through the armature coil 10B changes, the rotor 112, which is attracted to the magnetic field, rotates. I will do it. That is, the sixth
The driving force is obtained by the magnetic action of the substantially sinusoidal rotating magnetic field shown in the figure and the permanent magnet 116.

However, as is clear from FIG. 6, the armature coil 11
The rotating magnetic field created by 8 is actually distorted from a sine wave. That is, the rotating magnetic field does not rotate smoothly over time, but merely rotates at an irregular rotational speed due to the distortion.

Therefore, if we examine the rotation of the rotor of a conventional synchronous machine in detail, macroscopically the rotational speed matches the synchronous speed, but microscopically there is rotational unevenness due to small torque fluctuations. Completely smooth rotational force was not obtained.

Therefore, the applicant of the present application has proceeded with development with the aim of obtaining a rotating machine that exhibits stable characteristics with little variation in rotational torque. Invented an excellent AC rotating machine that could make equipment smaller and lighter, and filed an application for this first (patent application filed in 1983).
2-227801). It was subsequently discovered that this AC rotating machine had a unique configuration that had not been seen before, and that design techniques applied to conventional electric motors could not be used.

The invention according to the present application relates to an AC rotating machine that exhibits even more excellent characteristics by incorporating a newly developed design method to realize the above-mentioned AC rotating machine with excellent characteristics.

[Means for Solving the Problems] The configuration of the AC rotating machine of the present invention, which has been made to solve the above problems, is as follows. and an armature formed by fitting an armature coil between armature teeth continuously formed in the armature, and the armature are held facing each other with a predetermined gap so as to be mutually rotatable, and the armature coil is In an AC rotating machine that continuously changes the relative position of the field and the armature due to the magnetic action of the magnetic field produced by the armature and the magnetic field produced by the permanent magnet when passing through a phase current, the armature , a space in which one armature coil is fitted so as to wrap one armature tooth, and the field is a space in which a number of the armature teeth equal to the number of phases of the multiphase alternating current are arranged. Consisting of a large number of permanent magnets in which the number of permanent magnets is one more than the number of phases and arranged so that the polarity is alternate,
It is characterized in that the predetermined gap is regulated so that the magnetic resistance between the armature teeth and the field core is smaller than the magnetic resistance of adjacent armature teeth.

[Function] In the armature of the AC rotating machine of the present invention, armature coils are arranged independently of each other on each armature tooth. The field consists of permanent magnets with alternating polarity, one more than the number of phases, in a space where the number of armature teeth equal to the number of phases of the multiphase alternating current passed through the armature coil is arranged. It is arranged and configured as follows.

Therefore, the armature coil and armature teeth of the INA independently produce one magnetic field, and that field is not influenced by the magnetic fields produced by other armature coils and armature teeth. The magnetic field changes continuously from north pole to south pole in a smooth sinusoidal manner according to the multiphase alternating current supplied to the armature coil.

In addition, the permanent magnets of the field are placed in a continuously changing magnetic field as described above, and any one magnetic field created by the armature coil will always have a magnetic effect with two or more permanent magnets. A compatible relationship is established.

Therefore, due to the phase relationship between the armature and the field, the relative position between the armature and the field changes smoothly without maximum or minimum fluctuations appearing in the rotational torque.

Furthermore, the relative positional relationship between the armature and the field is such that the magnetic resistance between the armature teeth and the field core is smaller than the magnetic resistance of adjacent armature teeth.

Therefore, most of the magnetic lines of force originating from the armature teeth directly interact with the field due to the armature coil, and leakage flux between adjacent armature teeth is suppressed to the utmost, allowing for highly efficient conversion of electrical energy into mechanical energy. will be achieved.

EXAMPLES Hereinafter, in order to explain the present invention more specifically, the present invention will be described in detail with reference to Examples.

[Example] FIG. 1 is a schematic end view showing an AC rotating machine 10 of an example in a cross section perpendicular to its rotation axis.

Note that the AC rotating machine 10 of the embodiment is exemplified as having a configuration that uses three-phase AC as a power source.

As shown, the mechanical configuration of the AC rotating machine 10 is similar to that of a conventional rotating field type synchronous machine.

That is, the armature 20, which is a stator, has an armature core 22.
and an armature coil 24 attached to the armature core 22. The armature core 22 is constructed as follows so that eddy current loss is reduced and the armature coil 24, which has been wound in a predetermined shape, can be easily embedded and integrated.

Many thickness 0. A thrower (22a) into which the armature coil 24 is fitted is continuously formed in a circular shape using several [mm] of silicon steel plates, and the position sandwiched between the slots 22a serves as a path for the magnetic flux generated by the armature coil 24. It is manufactured by punching and forming the armature teeth 22b and laminating these silicon steel plates mutually insulatingly. Further, the armature coil 24 is constructed by winding a conductive wire a predetermined number of times in a shape suitable for fitting into the thrower 22a formed on the armature core 22, and then coating the wire with insulation.

However, the shape of the armature coil 24 formed by winding is different from that of a conventional rotating field type synchronous machine. As shown in the figure, each armature coil 24 has a shape suitable for being embedded in mutually adjacent slots 22a formed in the armature core 22, and has an elongated shape compared to the conventional one. Each armature coil 24 is arranged without overlapping each other.
It is completely independently fitted into the thrower 22a of the armature core 22 and fixed integrally. For this reason, one armature coil 24
The magnetic flux generated by the armature coil 24 constitutes one magnetic circuit with one armature tooth 22b serving as the coil magnetic core of the armature coil 24 as a magnetic path. That is, one armature tooth 22 constitutes an independent magnetic circuit and does not affect the magnetic state of other armature teeth 22.

In addition, in this embodiment, the armature core 22 has a slot 22a.
``24'' is formed. Therefore, the total number of armature coils 24 fitted into armature core 22 is also "24".

The field magnet 30, which is a rotor, has a structure different from that of the normal IJI machine, like the armature coil 24 described above. That is, since the armature 20 is configured as described above, the magnetic field created by the armature 20 is of U phase.

Rather than a sinusoidal magnetic field having an electrical angle of 2π being generated by the i yA armature coils 24 of the ■ and W phases, a unique magnetic field is created by the armature coils 24 of each phase. Therefore, the field 30 is arranged along the circumferential surface of the rotating iron core 320 in a space facing the one-silk armature coils 24 of the U phase, ■ phase, and W phase. It is constructed by bonding permanent magnets 34 such that their magnetic poles are alternate. Therefore,
As shown in FIG. 1, in this example, four permanent magnets are glued to each of eight magnets consisting of U phase, ■ phase, and W phase.
A total of 32 permanent magnets 34 are used.

In order to form a predetermined magnetic field in the armature coils 24 of the armature 20 configured as described above, each armature coil 24 is connected by a connecting wire 40a, 40b or 40c, and the phase is sequentially changed according to the arrangement order. Different three-phase alternating currents are passed.

Next, the relative positional relationship between the armature 20 and the field 30 configured as described above will be explained using FIG. 2.

FIG. 2 is an enlarged perspective view partially enlarging the opposing portions of the armature 20 and the field 30 so that the relative positional relationship between the armature 20 and the field 30 is clearly shown. The armature coil 24 is omitted. Further, in the figure, a magnetic circuit constituted by the armature 20 and the field 30 is indicated by dotted lines.

As shown in FIG. 2, by forming a magnetic flux path between the armature 20 and the field 30, a magnetic force acts between both members, and the field 30 can obtain rotational force. . Therefore, increasing the magnetic flux density between the armature 20 and the field 30
This leads to an improvement in the output torque of the AC rotating machine 10. Therefore, in this embodiment, the positional relationship between the armature 20 and the field 30 is determined with the following regularity.

Armature teeth 22 that serve as a path for the magnetic flux created by the armature coil 24
The surface facing the field 30 of b (a in the figure is a thrower) 2
In order to hold the armature coil 24 fitted into the armature coil 2a and to increase the area facing the field 30, the armature coil 2a is enlarged and has a facing area Aa. Further, the circumferential surface (b in the figure) of the tip of the armature m22b where the distance between adjacent armature teeth 22b is the smallest value "Ql" is:
The mechanical strength of the tip of the armature tooth 22b is
The armature coil 24 fitted in the armature coil 22a is held, and the thickness is suppressed to the extent that it can counteract the magnetic force acting between the armature coil 24 and the field magnet 30, and has a small area Ab. The distance between the tip of the armature tooth 22b and the field core 32 of the field 30 (i.e., the thickness tp of the permanent magnet 34 and the distance between the armature 20
and the gap tq between the field 8130 and the field 8130) is set to the value "Q2", these are constructed so as to satisfy the following equation.

What the above formula (1) means is the formation of a magnetic circuit for increasing the magnetic flux density between the armature 20 and the field 30, as described above. That is, the armature coil 24 and the permanent magnet 34 generate the magnetomotive force that creates the magnetic flux shown by the dotted line in FIG. A major factor that determines the magnetic resistance of the magnetic circuit is the distance Q, which is the sum of the separation distance tq between the armature teeth 22b and the permanent magnet 34 and the thickness tp of the permanent magnet 34.
It is 2. This is because air with a small magnetic permeability μ0 exists between the separation distance tq, and the magnetic permeability μp of the permanent magnet 34 is also small for the following reason.

It is essential that the magnetic material used as the magnet material has hysteresis characteristics of a large residual magnetic flux Br and a large coercive force HC, as shown in FIG. In other words, it exhibits characteristics extremely close to that of a square. The permanent magnet 34 is manufactured by magnetizing this magnetic body with a large current, and the permanent magnet 34 does not remain at point a or point b in FIG. 3, but maintains a residual magnetic flux ±Br. Therefore, even if a magnetic field Hg is applied from the outside to the permanent magnet 34 in this state, the magnetic flux density B inside the magnet shows only a small change of ΔB, and the magnetic resistance of the permanent magnet 34 is extremely large, and its magnetic permeability μρ is a small value between the air magnetic permeability μ0 and the path. Therefore, in order to reduce the magnetic resistance and increase the magnetic flux density of the magnetic circuit shown by the two-dot line in FIG. 2, it is necessary that (Q2/Aa) be small.

On the other hand, as is visually clear from Fig. 2, the armature tooth 2
The tip of the armature tooth 2b is separated by a distance Q from the adjacent armature tooth 22b.
1 is getting smaller. Therefore, adjacent armature teeth 22b
Magnetic flux leakage occurs between the two. This leakage magnetic flux only forms a closed circuit within the armature 20, and its energy is consumed as heat. That is, the magnetic circuit of this leakage magnetic flux is required to be configured to have as large a magnetic resistance as possible, and for that purpose, (Q1/Ab
) must be a large value.

In other words, the armature 20 is adjusted so as to satisfy the above equation (1).
When determining the relative positional relationship between the magnetic field 30 and the magnetic field 30, the AC rotating machine 10 becomes an excellent device that converts electrical energy into mechanical energy with high efficiency.

When a three-phase alternating current is passed through the AC rotating machine 10 of the embodiment configured as described above, the field 30, which is a rotor, rotates while generating extremely stable rotational torque. Next, the generation situation of this rotational torque will be explained in detail using the timing chart of FIG.

FIG. 4(A) shows the three-phase alternating current, ie, the excitation current, leading to the armature coil 24 of FIG. As is well known, when the U-phase current is taken as a reference, the ■-phase current is delayed by 120 electrical degrees, and the W-phase current is further delayed by 120 electrical degrees. In addition, the numbers "1" to "9" shown in the figure are
It shows the time of the timing chart shown in FIG. 4(B).

When the known three-phase current shown in FIG. This is shown in detail in FIG. 4(B).

First, the case of time "1" will be explained. At this time,
No current flows through the U-phase armature coil 24, and the magnetic field is "0". On the other hand, the V-phase and W-phase armature coils 24
Exciting currents of the same magnitude and opposite directions flow through them, and both generate magnetic fields of the same magnitude and opposite polarity. Therefore, the permanent magnet 34 of the field magnet 30 interacts with the magnetic fields created by the V and W phases, and the S pole is drawn directly under the ■ phase, and the N pole is drawn directly under the W phase, resulting in stability.

As time passes from the state "1" in FIG. 4(B), the U-phase current begins to flow, and an S-pole magnetic field is generated directly below it. On the other hand, the magnetic field of the N pole where the ■ phase was generated is further strengthened, and the S pole where the W phase was generated is weakened, and finally the state shown in "2" is reached. At this time, the permanent magnet 34 of the field 30 receives a strong attractive force from the magnetic field of the {circle around (2)} phase, and becomes stable at a position where the S-pole permanent magnet 34 is directly below it. That is, it is stabilized at a position slightly displaced to the left in the drawing from the stable state of "1" above, and the field 30 shown in FIG. 1 rotates counterclockwise.

When time has further passed and the time reaches "3" shown in FIG. The phases generate magnetic fields of the same magnitude and opposite polarity. Therefore,
At this time, permanent magnets 34 of different poles are attracted directly under each armature coil 24, and the S permanent magnet 34, which was previously located directly under the V phase, further moves to the left in the drawing and reaches the boundary with the U phase. Moving. That is, in FIG. 1, field 8130 moves further counterclockwise.

When time elapses to time "4" in FIG. 4(A), U
The excitation current of the phase becomes maximum, and the excitation current of other phases becomes small. That is, the magnetic flux distribution becomes similar to that at time "2", and the N-pole permanent magnet 34 is attracted directly below the U-phase. That is, the field 30 further rotates counterclockwise.

The above relationship continues to be established regularly and continuously as shown in FIG. 4(B), and at the time shown in FIG. 4(A).
9'', the rotation of one angle of the permanent magnet 34 bonded to the field magnet 30 is completed. That is, it rotates by 22.5° (=360/16).

According to the AC rotating machine 10 of this embodiment configured as described above, the following effects are obvious.

The electromagnetic force acting between the armature 20 and the field 30, that is, the rotational torque, is generated by continuous and regular magnetic action as shown in FIG. 4(B). Moreover,
The magnetic field generated by each armature coil 24 has a smooth sine wave shape based on the sine wave excitation current (see Fig. 4 (A)) supplied from the power supply without being influenced by other armature coils 24. and change. Further, the magnetic field generated by the armature coil 24 always interacts with two or more permanent magnets 34. Therefore, the 300 rotations of the field are extremely stable, with no cogging occurring, and exhibiting smooth rotational characteristics.

Furthermore, as shown in FIG. 1, when fitting the armature coils 24 to the thrower 22a, it is sufficient to simply insert the individual armature coils 24 into adjacent slots 22a. This simplifies the configuration of the rotating machine and simplifies manufacturing and maintenance. For example, if an abnormality occurs in one armature coil 24 during use, it can be easily replaced without affecting the other armature coils 24 when removing that armature coil 24 from the slot 22a.

Further, the magnetic field produced by each armature coil 24 is not canceled out by the magnetic field produced by other armature coils 24, and the relative positional relationship between the armature 20 and the field 30 is as described above (1).
) satisfies the formula. Therefore, almost all of the magnetic field generated by the armature coil 24 interacts with the permanent magnet 34. For this reason,
The electrical-mechanical conversion efficiency increases, and the entire device can be made smaller and lighter compared to the output torque.

Note that although the above embodiments illustrate a rotating field type rotating machine configuration, the present invention is not limited to such a configuration in any way.
The present invention may be embodied in various forms without departing from the gist of the present invention, such as a rotating armature-type rotating machine configuration or a configuration driven by a four-phase or more polyphase AC power source.

[Effects of the Invention] As described above in detail, in the AC rotating machine of the present invention, each winding of the rotating means is arranged spatially independently, so that the magnetic fluxes are not interlinked. Therefore, the magnetic field produced by one winding does not cancel out the magnetic field produced by the other windings. Moreover, since the magnetic resistance between the armature and the field is small, leakage flux is small, magnetic energy is effectively used, and the motor is highly efficient. That is, a rotating machine with the same output can be manufactured in a smaller size and lighter weight.

In addition, the field of the rotating means is such that in a space where a number of windings equal to the number of phases of the multiphase alternating current are arranged, permanent magnets whose number is one more than the number of phases are arranged so that the polarity is alternated. It is composed of many permanent magnets. Therefore, the magnetic field produced by each winding always exerts a magnetic effect on two or more of the plurality of permanent magnets. Furthermore, the magnetic field produced by the winding is not affected by other magnetic fields and changes smoothly in a sinusoidal waveform according to the sinusoidal excitation current of the multiphase alternating current that is the power source. Therefore, with respect to the relative positional relationship between the field and the armature, the magnetic force acting between the field and the armature is extremely stable, and the rotational torque is extremely stable.

Furthermore, since the windings of the rotating means are arranged spatially independently, it is simple and easy to design, use, and maintain.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of an AC rotating machine that is an embodiment of the present invention, Fig. 2 is an enlarged perspective view for explaining the relative positional relationship between the armature and the field, and Fig. 3 is the field. Fig. 4 (A) is an explanatory diagram of the phase relationship of the three-phase AC current supplied to the AC rotating machine of the example, and Fig. 11 (B) is the hysteresis characteristic of the magnetic material used as the magnet material. An explanatory diagram of the operation of the field rotating by the three-phase alternating current, Fig. 5 is a cross-sectional view of a conventional synchronous machine, and Fig. 6 is an explanatory diagram of the rotational operation of the conventional synchronous machine.
It shows. 10... AC rotating machine 30... Field 22a... Suit 24... Armature coil 34... Permanent magnets 40a, 40b, 40C - Connection wire

Claims (1)

[Claims] 1. An electric machine in which an armature coil is fitted between a field created by a large number of permanent magnets arranged in a circular shape around a field core and armature teeth continuously formed in a circular shape. and the armature coils are held facing each other with a predetermined gap so as to be mutually rotatable, and when a multiphase alternating current is passed through the armature coil, the magnetic field generated by the armature and the magnetic field generated by the permanent magnet are combined. In an AC rotating machine in which the relative position of the field and the armature is continuously changed by action, the armature is fitted with one armature coil so as to wrap around one armature tooth. configured such that the field has a number of permanent magnets one more than the number of phases in a space in which a number of the armature teeth equal to the number of phases of the multiphase alternating current are arranged so that the polarity thereof is alternated. It is constructed by a large number of arranged permanent magnets, and the predetermined gap is regulated so that the magnetic resistance between the armature teeth and the field core is smaller than the magnetic resistance of adjacent armature teeth. An AC rotating machine featuring: