JPS6188761A - Rotary converter - Google Patents

Abstract

PURPOSE:To improve the reliability by respectively disposing armature windings of AC and DC sides separately at stator and rotor sides, thereby reducing mutual interference. CONSTITUTION:A rotary converter has a rotor 8 and a stator 9 provided at the prescribed interval on the outer periphery of the rotor 8. The rotor 8 is formed of a magnetic rotor body 10 and a conductive cylinder 11 engaged fixedly with the outer periphery of the body, and the stator 9 is formed of a ring-shape wound superconductive field winding 12, a vessel 13, a yoke 14, a current collector of a brush 16, an output terminal 17, and a DC exciting power source 18. Further, a polyphase AC armature winding 19 is disposed in an air gap between the rotor 8 and the yoke 14 of the stator 9, secured to the inner periphery of the yoke 14, and a magnetic shielding plate 20 for protecting the winding 12 against the AC magnetic field by the winding 19 is provided. Thus, when the rotor 8 is rotated, the rotary shaft direction of the cylinder 11 crosses a sole pole magnetic flux phi, a DC voltage is inducted at this portion to produce a DC power from the brush 16.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a rotary current transformer that converts DC power to AC power or AC power to DC power, and particularly relates to a rotary current transformer that converts DC power to AC power or AC power to DC power. Regarding rotary current transformers.

[Background of the invention]

As shown in Figure 7, a rotary current transformer that converts DC power into AC power or AC power into DC power is a combination of a synchronous generator (or synchronous motor) and a DC motor (or DC generator). It is known what was done.

That is, the main part is composed of a fixed magnetic pole 1 and a DC armature 3 with a commutator 2 rotating therein, and its X-mature winding is divided into multiple phases and led to a current collecting ring 4. ing. For example, in the case of a three-phase system, there are three current collecting rings 4, and if a three-phase power source is connected to these, this rotary current transformer rotates as a synchronous motor and slides relatively on the commutator 2. Direct current Id can be taken out by the brush 5. Furthermore, if a DC current lα is passed through the armature winding from the brush 5 through the commutator 2, the armature rotates as a DC motor, and a three-phase AC current Iα can be taken out from the current collector ring 4. In the figure, 6 is a bearing that supports the rotor, and 7 is a yoke for the magnetic pole 1.

In this way, conventional rotary current transformers have a commutator and current collector ring connected to a common rotating armature winding, and in the past, they were popular in fields that required DC power, such as electric railways and electrochemical industries. However, with the advent of static converters such as silicon rectifiers and SIRISK, they are no longer manufactured.

However, in recent years, fields such as nuclear power, plasma, MHD, and nuclear fusion require low voltage and high current of tens of thousands of amps.
Some believe that a rotating current transformer with greater overload capacity is more desirable than a static converter. However, conventional rotary current transformers have the following drawbacks, and improvements are desired.

In other words, in a rotary current transformer, the armature windings of the synchronous machine and the DC machine are shared, so disturbances on the AC side directly affect the DC side, causing flashover in the commutator. Since the same armature winding cuts the same magnetic flux and induces both AC and DC electromotive forces, the DC side voltage cannot be controlled independently of the AC side voltage, and performance is unstable at high frequencies. There were drawbacks such as:

In addition, because AC output is taken out through a current collector ring, insulation of the current collector ring becomes a problem, making it difficult to increase high voltage and capacity, and the mechanical strength of the rotor windings and their connections. There have been problems such as the difficulty of increasing the speed of the rotor and obtaining high frequency alternating current.

[Purpose of the invention]

An object of the present invention is to provide a rotary current transformer that can reduce mutual interference between the DC side and the AC side.

[Summary of the invention]

To achieve this object, the present invention provides a rotating current transformer for converting DC power into AC power, which includes a fixed superconducting field winding, a fixed magnetic path, and a rotating magnetic path that form a unipolar magnetic field, and a fixed superconducting field winding, a fixed magnetic path, and a rotating magnetic path that form a unipolar magnetic field, a fixed multiphase AC armature winding disposed so as to be interlinked with a unipolar magnetic field in a gap between the fixed magnetic path and the rotating magnetic path forming either an outgoing path or a return path of the magnetic field; means for alternately making the magnetic flux distribution denser and denser in the circumferential direction in a portion of the rotating magnetic path that faces the fixed multiphase AC armature winding; and the rotation forming either an outgoing path or a returning path of the unipolar magnetic field. A rotating conductor arranged in a magnetic path so as to be interlinked with a unipolar magnetic field, and a current collector for causing a DC current to flow through the rotating conductor, the fixed superconducting field winding being DC excited, and A DC current is passed through the rotating conductor to drive it as a DC motor and generate a multiphase AC voltage in the fixed multiphase AC armature winding,
In addition, in a rotary current transformer that converts AC power to DC power, a fixed superconducting field winding, a fixed magnetic path, and a rotating magnetic path that form a unipolar magnetic field, and one of the outgoing and return paths of this unipolar magnetic field. A fixed multiphase AC 1! is arranged so as to be interlinked with a unipolar magnetic field in the gap between the fixed magnetic path and the rotating magnetic path forming the fixed magnetic path. Isogo winding; a first rotating conductor disposed in a portion of the rotating magnetic path facing the fixed multiphase AC armature winding;
a second rotating conductor disposed in the rotating magnetic path that forms either an outgoing path or a returning path of the unipolar magnetic field so as to be interlinked with the unipolar magnetic field; and direct current power is supplied from the second rotating conductor. the fixed superconducting field winding is DC-excited, and the fixed multiphase AC armature winding is AC-excited to drive it as an induction motor and the second rotating It is characterized by 5K to generate DC voltage in the conductor.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in detail based on the illustrated embodiment.

1 is a partially cutaway perspective view of a rotary current transformer according to an embodiment of the present invention, and in FIG. 2, the right half is taken along the line A-A in FIG. 1, and the left half is taken along the line B-- It is a sectional view along the B line.

The rotary current transformer of this embodiment consists of a rotor 8 and a stator 9 provided at a predetermined interval on the outer periphery of the rotor 8. The rotor 8 is composed of a magnetic rotor body 10 and a conductive cylinder 11 made of a non-magnetic quaternary material such as copper, which is fitted and fixed to the outer periphery of the body. On the other hand, the stator 9 has a ring-wound superstructure connected to the Sakai field winding 12, a container 13 for supporting and cooling the winding 12, a yoke 14, and a brush holder 15 inside 16. The connected output terminal 17, the external DC excitation power supply 18 connected to the field winding 12, the rotor 8 and the stator 9
A multiphase AC armature winding 19 is disposed in the gap between the yoke 14 and the yoke 14 and is fixed to the inner circumferential surface of the yoke 14. It consists of an electromagnetic yield plate 20 that protects the rotor, and a bearing 21 that supports the rotor. Note that a predetermined number of concave portions 10α and convex portions 10b are alternately formed in the circumferential direction of the portion of the magnetic rotor body 10 that faces the armature winding 19 in the direction of the rotation axis. The portion that does not correspond to the armature winding 19 in the axial direction has a smooth cylindrical shape. Further, the armature winding 19 has a so-called helical structure in which each coil is skewed by 180 electrical degrees.

In the rotary current transformer configured as described above, when obtaining an AC output from the armature winding 19, first the superconducting field winding 12 is DC excited by the external DC excitation power supply 18 to generate a single pole magnetic flux Φ. The number of people who appear, 14, 1111i; The magnetic flux Φ is first spatially uniformly incident on the smooth conductive cylinder 11 and the magnetic rotor body 10 on the side opposite to the armature winding of the rotor 80 from the yoke 14. Next, the magnetic flux Φ that has passed through the inside of the magnetic rotor body 10 in the direction of the rotation axis is transmitted to the magnetic rotor body 10 alternately in the circumferential direction by recesses 10α and convex portions 10b in the portion in the rotation axis direction opposite to the electric prewinding 519.
Since the magnetism is formed in a large area, the magnetism is concentrated in the convex portion 10b having a small magnetic resistance, and is spatially distributed alternately in a dense and dense manner when viewed in the circumferential direction.

This situation is shown in a developed diagram as shown in Figure 3.

That is, in the concave portion 10a of the magnetic rotor body 10 of the rotor 8, the gap length between the stator 9 and the yoke 14 is longer than the gap length between the convex portion 10b and the yoke 14; The distribution of the magnetic flux density BT in the gap corresponding to 10α is concave, and conversely, the distribution of the magnetic flux density aBr in the gap corresponding to the convex portion 1010h is convex.

The magnetic flux Φ, which is spatially distributed alternately in a dense and dense manner when viewed in the circumferential direction, cuts the armature winding 19 and then enters the yoke 14, but as it passes through the yoke 14, K , the distribution eventually becomes smooth.

On the other hand, at the same time, when a DC current 1d is supplied from the outside to the rotor 8 via the brush 16, this DC current Id flows through the conductor circle ftJ11 in the direction of the rotation axis and connects to the armature winding 19 of the rotor 8. The rotor 8 rotates because it interlinks with the unipolar magnetic flux φ on the surface of the opposing rotating shaft direction portion, and rotational torque is generated by the interaction trap. The rotation speed N of this rotor 8
is the current in the field winding 12 or the direct current! It can be controlled to a predetermined value by increasing or decreasing R and Id.

When the rotor 8 rotates, the single %m flux Φ, which is spatially distributed unevenly in the armature winding 19, moves sequentially in time, so that the DL8a child winding 19 A multiphase AC voltage having a frequency proportional to the number of uneven portions 10α, 10b of the magnetic rotor body 10 and the rotation speed N of the rotor 8 is induced, and this is outputted from an output terminal (not shown).

Note that the uneven portion 10α of the magnetic rotor body 10.

The uneven distribution of the monopole magnetic flux Φ gradually flattens as it moves away from the rotor 10b, so in order to effectively generate AC output, it is desirable to place the armature winding 19 as close to the rotor 8 as possible. .

Although the case where DC power is converted to AC power has been described above, it is also possible to convert AC power to DC power in the opposite manner. In this case, as in the previous case, the superconducting field winding 12 is DC excited to form a unipolar magnetic field, and the armature winding 19 is AC excited by an external AC power source (not shown) to generate a multi-phase Forms a rotating magnetic field. This rotating magnetic field generates a secondary induced current in the conductive cylinder 11 of the rotor 8,
The conductive cylinder 11 acts as a rotor damper of the induction motor to generate a starting torque, and the rotor 8 is started. Rotor 8
When the zero rotation speed increases and reaches the synchronous speed, armature winding 1
The rotor rotates as a synchronous motor due to the electromagnetic action between the rotating magnetic field produced by 9 and the 1 oz convex portion of the magnetic rotor body 10.

When the rotor 8 rotates in this way, the part in the direction of the rotation axis faces the armature winding 19 of the conductive cylinder 11.
A DC voltage is induced in this portion, and DC power can be extracted from the brushes 16 arranged at both ends.

According to this embodiment, the following various effects can be obtained.

(1) Unlike conventional rotary current transformers, the armature windings on the AC side and DC side are not shared, but are arranged separately on the stator side and rotor side, respectively. Since it is absorbed by the damper effect of the conductive cylinder 11 placed over the child's surface, there is little direct influence on the direct current side, and stable operating characteristics can be obtained.

(2) Since we adopted a so-called helical structure in which the armature winding 19 is arranged with a spatial inclination of about 180 electrical degrees, the AC output voltage caused by the harmonic components of the magnetic flux Φ distributed in an uneven manner is reduced. Distortion is canceled and AC power with a clean sinusoidal waveform is obtained.

(3) In order to increase the frequency of the AC output, it is possible to increase the number of rotations N or to rotate the magnetic flux as described above, but the rotor 8 of this embodiment does not have any windings and does not rotate. Since it has a simple structure consisting of a block-shaped magnetic rotor body 10 having uneven parts 10α and 10b in a part in the axial direction, and a conductive cylinder 11 that is fitted and fixed to the outer circumference of the body 10, the mechanical structure is strong against centrifugal force. It has a large target strength (can be easily rotated at high speed and can obtain high frequency AC output.

(4) Since the outer circumferential surface of the rotor 8 has a smooth structure, an increase in windage loss due to high-speed rotation can be suppressed.

(5) In the conventional iron core slot winding system, there was a problem that the higher the output frequency, the more the armature winding itself increases, resulting in a voltage drop and the inability to effectively extract the output. In this case, since the air gap winding method is adopted, the reactance can be significantly reduced, and the above-mentioned problem is also eliminated.

(6) The armature winding 19 has a helical structure, with no coil end portion extending outward in the radial direction, and has a cylindrical shape as a whole, making it possible to make one rotary current transformer compact.

(7) Since both the superconducting field winding 12 and the armature winding 19 are placed on the stator side, maintenance of the former, such as vacuum insulation and helium supply and discharge, is easy, and the machine Reliability can be improved, and since AC output can be taken out without using a collector such as a current collecting ring, high voltage and large power can be easily taken out.

In addition, in the above embodiment, the configuration is such that DC power can be converted to AC power, and AC power can be converted to DC power.
It can be configured to simply convert DC power into AC Rt power,
Alternatively, it may be configured to simply convert AC power into DC power.

That is, when simply converting DC power to AC power, it is not necessary to provide the conductive cylinder 11 with a function of generating a secondary induced current due to the rotating magnetic field, and for example, the armature winding 19 of the conductive cylinder 11 and It is possible to omit the opposing portion in the direction of the rotation axis, and to provide brushes at both ends of the portion in the direction of the rotation axis on the opposite side, so that a direct current flows through this portion. In addition, when simply converting AC power into DC power, a means for alternately making the magnetic flux distribution of the rotor portion facing the armature winding 19 denser and denser in the circumferential direction, that is, the uneven portion 10α of the magnetic rotor body 10 is used. , 10h can be omitted to make this part smooth. However, in this case, the armature winding 19 and the conductive cylinder 11 are always driven to rotate only as an induction motor, and not as a synchronous motor.

FIG. 4 is a partially cutaway perspective view of a rotary current transformer according to another embodiment of the present invention, and FIG. 5 is a side view taken along line CC in FIG. 4.

In this embodiment, instead of the conductive cylinder 11 of the previous embodiment,
A plurality of conductive bars 22 made of a conductive material such as copper and having a dovetail cross section are buried in the magnetic rotor body 10 at equal intervals in the circumferential direction so as not to be ejected due to centrifugal force. A filling member 23 made of a non-magnetic material such as stainless steel is filled in the recess 10α of the rotor 8 (embedded so as not to pop out due to centrifugal force, and the outer circumferential surface of the rotor 8 is formed smoothly. are electrically connected to each other by the shorting piece 24. Therefore, according to this embodiment, in addition to obtaining the same effect as the previous embodiment, each conductive bar 22 is electrically connected to the brush 16 and the shorting piece 24. Since it is short-circuited by the piece 24, the transient damper current can easily flow in an orderly manner, and the armature reaction due to the negative phase component from the armature winding 19 during single-phase or unbalanced load operation can be absorbed. Even during such abnormal operation, it is possible to reduce the waveform distortion of the armature induced voltage and the vibration of the machine, and when driving the rotor 8 from the AC side, damper current tends to flow, so it is possible to reduce the waveform distortion at startup. It is possible to increase the rotational torque including the

Moreover, FIG. 6 is a partially cutaway perspective view of a rotary current transformer according to still another embodiment of the present invention.

This embodiment differs from the embodiment shown in FIG. 1 in that a current collector such as a brush 16, which was placed at the end of the shaft on the side of the armature winding 19, is placed at the end of the shaft on the side of the armature winding. As a result, the 7I current circuit on the rotor 8 is separated into a DC side and an AC side, and the inner peripheral portion of the yoke 14 facing the armature winding 19 is made into a laminated iron core 25 stacked in the direction of the rotation axis. That's true.

Therefore, in addition to obtaining the same effects as the embodiment shown in FIG. 1, mutual interference between the AC side and the DC side is eliminated, and
The load characteristics of the AC machine can be improved, and the iron loss generated in the yoke 14 due to the uneven distribution of the unipolar magnetic flux Φ and the iron loss generated in the yoke 14 due to the armature reaction magnetic flux can also be reduced.

In each of the above embodiments, one armature winding and one superconducting field winding are provided in the direction of the rotation axis, but the present invention is not limited to this. They can also be connected in cascade, and in this way it is possible to obtain a rotating current transformer with an even larger capacity.

〔Effect of the invention〕

As explained above, according to the present invention, the armature windings on the AC and DC sides are not shared and are arranged separately on the stator and rotor sides, so that mutual interference between the AC and DC sides In addition, stable operating characteristics can be obtained by reducing the air gap winding due to the interaction between the unipolar magnetic flux generated by the superconducting field winding on the stator side and the means for making the magnetic flux distribution coarse and dense formed in a part of the rotor. Since alternating current output is generated in the type armature winding, reliability is improved and reactance is reduced, making it possible to generate large capacity and highly efficient power even with high frequency output. Furthermore, since the rotor can easily rotate at high speed, it is possible to obtain high-frequency AC output.

[Brief explanation of drawings]

1 is a partially cutaway perspective view of a rotary current transformer according to an embodiment of the present invention, and in FIG. 2, the right half is taken along the line A-A in FIG. 1, and the left half is taken along the line B-- 3 is an explanatory diagram of the operation of the rotary current transformer, FIG. 4 is a partially cutaway perspective view of a rotary current transformer according to another embodiment of the present invention, and FIG. 5 is a cross-sectional view taken along line B. Number of times seen from line C-C in Figure 4, 8... Rotor, 9...
Stator, 10...Magnetic rotor body, 10α...
...Concave portion, 10b...Convex portion, 11...
...Conducting cylinder, 12...Superconducting field winding, 14
...Yoke, 16...Brush, 19...
... Polyphase AC armature winding, 22 ... Conductive bar. Figure 1 Figure 2 Figure 3 Figure 4 Figure 6 Figure 7

Claims (1)

[Claims] 1. In a rotary current transformer that converts DC power to AC power, a fixed superconducting field winding, a fixed magnetic path, and a rotating magnetic path that form a unipolar magnetic field, and an outgoing path of this unipolar magnetic field. or a fixed multiphase AC armature winding arranged so as to be interlinked with a unipolar magnetic field in a gap between the fixed magnetic path and the rotating magnetic path forming either one of the return paths; means for alternately making the magnetic flux distribution denser and denser in the circumferential direction in a portion of the path facing the fixed multiphase AC armature winding; A rotating conductor arranged to interlink with a unipolar magnetic field, and a current collector for passing a DC current through the rotating conductor, the stationary superconducting field winding being DC-excited, and the rotating conductor A rotary current transformer characterized in that the rotary current transformer is driven as a DC motor by passing a DC current through the fixed multiphase AC armature winding, and generates a multiphase AC voltage in the fixed multiphase AC armature winding. 2. The rotary current transformer according to claim 1, wherein the fixed multiphase AC armature winding has a helical structure. 3. The rotary current transformer according to claim 1, wherein the rotating conductor is a conductive cylindrical body. 4. The rotary current transformer according to claim 1, wherein the rotating conductor comprises a plurality of conductive bars arranged at intervals in the circumferential direction. 5. Claim 1 is characterized in that the fixed multiphase AC armature winding is disposed on either the outgoing path or the return path of the unipolar magnetic field, and the rotating conductor is disposed on the other side. Rotating current transformer. 6. In a rotary current transformer that converts AC power into DC power, a fixed superconducting field winding, a fixed magnetic path, and a rotating magnetic path that form a unipolar magnetic field, and either the outgoing path or the return path of this unipolar magnetic field. a fixed multiphase AC armature winding disposed so as to be interlinked with a single pole magnetic field in a gap between the fixed magnetic path and the rotating magnetic path forming the fixed multiphase AC armature winding of the rotating magnetic path; A first rotating conductor disposed in a portion facing the armature winding and the rotating magnetic path forming either an outgoing path or a returning path of the unipolar magnetic field are arranged to interlink with the unipolar magnetic field. The second
and a current collector for extracting DC power from the second rotating conductor, the fixed superconducting field winding is DC excited, and the fixed multiphase AC armature winding is AC excited. The second motor is driven as an induction motor.
A rotating current transformer characterized by generating a DC voltage in a rotating conductor. 7. The rotating current transformer according to claim 6, characterized in that the first rotating conductor also serves as the second rotating conductor. 8. A rotary current transformer according to claim 6, wherein the fixed multiphase AC armature winding has a helical structure. 9. The rotary current transformer according to claim 6, wherein the first and second rotating conductors are comprised of conductive cylindrical bodies. 10. The rotary current transformer according to claim 6, wherein the first and second rotating conductors are composed of a plurality of conductive bars arranged at intervals in the circumferential direction. . 11. Claim 6 provides that the fixed multiphase AC armature winding is disposed on one of the outgoing and returning paths of the unipolar magnetic field, and the second rotating conductor is disposed on the other. Characteristic rotating current transformer. 12. Claim 6, further comprising means for alternately making the magnetic flux distribution of a portion of the rotating magnetic path facing the fixed multiphase AC armature winding denser and denser in the circumferential direction,
The fixed superconducting field winding is DC-excited and the fixed multiphase AC armature winding is AC-excited to drive it as an induction synchronous motor and to generate a DC voltage in the second rotating conductor. A rotary current transformer featuring: