JPH07231631A - Brushless high-frequency-absorption synchronous machine - Google Patents

Abstract

PURPOSE:To omit a slip ring and a brush by a method wherein a first AC exciter which supplies a prescribed DC exciting current and a second AC exciter and a third AC exciter whose frequency is at a specific multiple of a fundamental frequency and which supply a harmonic current having a prescribed phase difference are installed by sharing the field-pole drive shaft of a synchronous machine. CONSTITUTION:A first AC exciter 2 provided with an armature winding 2a to supply a DC current to a winding 1b via a rotary rectifying device 5 is arranged and installed. Then, a second AC exciter 3 and a third AC exciter 4 whose frequency is 6n times the fundamental frequency, by which two sets of harmonic currents at a mutual phase difference of 90 deg. are output respectively from their armature windings, 3a, 4a and which supply a current to windings 1c, 1d are arranged and installed. The first, second and third AC exciters 2, 3, 4 are installed by sharing the field-pole drive shaft 20 of a three-phase synchronous generator 1. Thereby, a slip ring and a brush are not required between the three-phase synchronous generator 1 and the individual AC exciters 2, 3, 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-phase AC synchronous machine having a function of absorbing a specific harmonic wave superimposed on a fundamental wave voltage of an AC system associated with the AC system.

[0002]

2. Description of the Related Art As a conventional three-phase AC synchronous machine having this kind of higher harmonic absorption function, there are the following ones proposed by the applicants of the present invention in Japanese Patent Application No. 3-293212. That is, a first field winding that generates a magnetic flux for generating a fundamental wave voltage and a second field winding that generates a magnetic flux in the direction perpendicular to the field pole are provided in the field pole of the rotary field synchronous machine. , A third field winding that generates a magnetic flux in the horizontal axis direction of the field pole, and a harmonic current having a frequency of 6 nf (n is a positive integer) with respect to the frequency f of the fundamental wave is supplied to both the second and third fields. By energizing the field windings respectively and giving a predetermined phase difference between the both harmonic currents, for example, when the second and third field windings are arranged orthogonally, the both harmonic currents are By making the phase difference between them 90 degrees, a frequency of 6
A rotating magnetic field having an angular velocity corresponding to nf is generated, and by this, the harmonic component is superposed on the fundamental wave voltage of the AC system with which the synchronous machine is linked and its frequency is (6n ± 1) f, and is substantially equal in value and reverse. The voltage component of the phase is generated in the armature of the synchronous machine that interlinks with the rotating magnetic field, and functions to eliminate or reduce the AC system side higher harmonic component.

[0003]

However, in the conventional harmonic absorption synchronous machine as described above, the phase relationship of the rotating magnetic field with respect to the fundamental wave voltage, and hence the armature of the synchronous machine interlinking with the rotating magnetic field. It is not possible to make the phase relationship of the harmonic voltage generated in the variable.Therefore, the phase relationship of the rotating magnetic field is set to an appropriate value in accordance with the superimposed phase of the AC system side harmonic component with respect to the fundamental wave voltage as described above. It was not possible to adjust it, and there was a limit to effectively eliminating or reducing the harmonic component on the system side.

Further, in the conventional harmonic absorption synchronous machine as described above, a required DC current or harmonic current is supplied from each circuit on the fixed side to each of the first to third field windings through slip rings. Therefore, complicated work such as maintenance inspection and replacement work for the surface roughness or wear of the slip ring and the brush to be brought into contact with the slip ring is required.

In view of the above, the present invention has the function of effectively eliminating or reducing the harmonics on the AC system side as described above, in other words, having an effective absorption function, and omitting the slip ring and the brush. The purpose of the present invention is to provide a brushless type three-phase AC synchronous machine that can be used.

[0006]

In order to achieve the above object, in the brushless type harmonic absorption synchronous machine of the present invention, 1) the invention of claim 1 is basically applied to a field pole of a rotary field synchronous machine. A first field winding for generating a magnetic flux for generating a wave voltage,
A second field winding for generating magnetic flux in the direction of the field pole straight axis;
A third field winding that generates a magnetic flux in the direction of the horizontal axis of the field pole is provided, and a harmonic current having a frequency of 6 nf (n is a positive integer) with respect to the fundamental wave frequency f is supplied to the second and third field magnets. The frequency 6 is applied to the field pole by energizing the windings and applying a predetermined phase difference between the harmonic currents.
In a harmonic absorption synchronous machine configured to generate a rotating magnetic field having an angular velocity corresponding to nf, a rotary armature for supplying a required DC exciting current to the first field winding through a rotary rectifier. -Type first AC exciter, a rotary armature-type second AC exciter that supplies a harmonic current having a frequency of 6 nf to the second field winding, and the third AC exciter. A rotating armature type third having a frequency of 6 nf for the field winding and supplying a harmonic current having a predetermined phase difference with the harmonic current supplied to the second field winding.
The field exciter of the synchronous machine is provided in common with the AC exciter.

2) The invention of claim 2 is the brushless type harmonic absorption synchronous machine according to the invention of claim 1, wherein the second
With respect to the third and third alternating-current exciters, stator frame drive means for independently changing the field poles of the two exciters through the respective stator frames in the circumferential direction by a required angle is provided. 3) The invention of claim 3 relates to the second and third alternating-current exciters in the brushless harmonic absorption synchronous machine according to the invention of claim 1, in which the direct-current exciting current for feeding the respective field windings is supplied. By adjusting, the armature output current of each of the exciters can be independently adjusted.

4) The invention of claim 4 is the brushless harmonic absorption synchronous machine according to the invention of claim 1, wherein the second
With regard to the third and third alternating-current exciters, two sets of field windings for direct-current excitation arranged orthogonally to each other are provided in the field poles of both exciters. 5) According to a fifth aspect of the invention, in the brushless harmonic absorption synchronous machine according to the fourth aspect of the invention, the DC currents supplied to the two sets of DC excitation field windings arranged orthogonal to each other can be independently adjusted. And

[0009]

In general, N sets of windings arranged with a mechanical angle difference of 360 / N degrees are supplied with N sets of currents having a frequency f and having an electrical angle phase difference of 360 / N degrees. If
A rotating magnetic field having an angular velocity corresponding to the frequency f is generated on the magnetic pole. Therefore, excitation is performed by the first field winding for generating the fundamental wave voltage of the frequency f and the harmonic current of the frequency 6nf (n is a positive integer) by receiving the DC excitation on the field pole of the rotary field type synchronous machine. The second field winding that generates a magnetic flux in the direction perpendicular to the receiving magnetic pole and the second field winding has a phase difference of 90 degrees with respect to the harmonic current for exciting the second field winding, and its frequency is 6 nf. By providing a third field winding for generating a magnetic flux in the horizontal axis direction of the field pole upon being excited by the harmonic current, a DC magnetic field and a rotating magnetic field having an angular velocity corresponding to a frequency of 6 nf are provided on the field pole. It will be mixed and generated.

Here, the rotating magnetic field corresponding to the frequency 6 nf is (6
It can be decomposed into two sets of rotating magnetic fields having angular velocities corresponding to both frequencies of (n + 1) f and (6n-1) f. Therefore, both voltage components of the frequencies (6n + 1) f and (6n-1) f are generated in the armature of the synchronous machine that intersects with these two sets of rotating magnetic fields.

On the other hand, a significant one of the harmonic components superposed on the fundamental wave of the AC system with which the synchronous machine is linked is the one whose frequency is (6n ± 1) f. Therefore, the frequency (6n ± 1) generated in the armature of the synchronous machine
If both harmonic voltage components of f are adjusted so that they are substantially equal in value and opposite in phase to the harmonic components of the same frequency in the AC system, most of the harmonic components in the AC system are of the synchronous machine. It will disappear in the armature. In other words, it will be absorbed in the armature of the synchronous machine.

According to the present invention, brushless power feeding means for supplying a required exciting current to each field winding in the synchronous machine and the armature of the synchronous machine corresponding to the superposed phase of the harmonic component in the AC system on the fundamental wave. And a phase adjusting means for adjusting a generation phase of a harmonic component generated in 1), 1) The invention of claim 1 is a first for generating a fundamental wave voltage provided in a field pole of a rotary field type synchronous machine. It was provided to generate a rotating magnetic field of angular velocity corresponding to a frequency of 6 nf, together with the first alternating-current exciter of the rotating armature type that supplies a required direct current to the field winding of the device through the rotating rectifier. Second as above
In order to supply the required harmonic excitation current to both the third and third field windings, a rotating armature type second AC exciter that outputs a harmonic current with a frequency of 6 nf and its frequency is 6 nf A rotating armature-type third AC exciter that outputs a harmonic current having a predetermined phase difference, for example, 90 degrees, from the harmonic current output from the second AC exciter, and a field pole of the synchronous machine. The drive shaft is commonly provided, and the synchronous machine as a whole is of a brushless type.

2) The invention of claim 2 is based on the phase of the fundamental wave voltage of the synchronous machine, and the (6n ± 1) f harmonic voltage component in the AC system and the frequency 6nf in the synchronous machine. The present invention relates to phase adjustment between both harmonic voltages, which are performed so that the induced voltage due to the corresponding rotating magnetic field has an opposite phase, and relates to the second and third alternating-current exciters according to the invention of claim 1, and fixes each of them. Stator frame drive means for independently changing the field pole in the circumferential direction by a required angle is provided.

3) The invention of claim 3 relates to voltage adjustment for making the magnitude of the harmonic induced voltage of the synchronous machine by the rotating magnetic field substantially equal to the harmonic voltage component of the AC system. The second and third aspects of the invention of claim 1
With respect to both AC exciters, the DC output current supplied to each field winding can be adjusted to independently adjust the armature output current of each of the exciters.

4) According to a fourth aspect of the invention, the phase adjustment between the both harmonic voltages is performed by electrical means instead of mechanical means such as the stator frame driving means. Regarding the second and third alternating-current exciters according to the invention, two sets of field windings for direct-current excitation arranged orthogonally in each fixed field pole are provided, and magnetic fluxes generated by these two field windings are combined. The required phase adjustment is performed by adjusting the direction of the magnetic flux.

5) According to the invention of claim 5, the magnitude and the direction of the synthetic magnetic flux generated by the invention of claim 4 are continuously variable, and the two sets of DC excitation field windings are fed with power. It is possible to independently adjust the DC exciting current.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In each of the above-mentioned drawings, the same reference numeral is given to the component having the same function. First, FIG. 1 is a half cross-sectional view of a main portion of a brushless synchronous generator showing a first embodiment of the present invention for a three-phase synchronous generator, which is in accordance with the invention of claim 1. Where 1 is a three-phase synchronous generator of fixed rotating field armature type,
Reference numeral a denotes an armature winding (stator side winding), and reference numerals 1b, 1c and 1d denote first, second and third field windings provided on the rotating field poles, respectively.

Reference numerals 2 and 3 and 4 are first, second, and third AC exciters, respectively, which are rotary armature fixed field AC generators, and 2a and 2b are respectively. 1 AC exciter 2 armature winding and field winding, 3a and 3b are respectively 2nd AC exciter 3 armature winding and field winding, 4a and 4b are respectively 3rd AC exciter Reference numeral 4 denotes an armature winding, field winding, and 5 are rotary rectifiers composed of bridge rectifying elements.

Here, the armature winding 1a of the three-phase synchronous generator 1
Is connected to an alternating current system that outputs the output of this synchronous generator, and the field windings 2b, 3b and 4b of the first to third alternating current exciters are respectively connected to external exciting devices (not shown). Receive a predetermined DC excitation. Further, the first field winding 1b of the three-phase synchronous generator 1 receives the output of the armature winding 2a of the first AC exciter 2 which has been converted into DC through the rotary rectifier 5, and is DC-excited. Second field winding 1 of generator 1
c and the third field winding 1d are subjected to AC excitation by the outputs of the armature windings 3a and 4a of the second and third AC exciters, respectively.

As shown in the figure, the three-phase synchronous generator field pole, the armature of each of the first to third AC exciters, and the rotary rectifier are respectively the drive shaft of the synchronous generator field pole, that is, the power generation. Since the machine shaft 20 is also used as its drive shaft, the slip ring and the brush for exchanging the exciting current between the three-phase synchronous generator and each AC exciter are not required, and the brushless synchronous generator is obtained. Will be configured.

FIG. 3 is a circuit diagram of a brushless synchronous generator including the above three-phase synchronous generator and AC exciters. Here, the second and third field windings 1c and 1d, which are orthogonally displayed on the rotating field poles of the three-phase synchronous generator 1, respectively have their magnetic flux generation directions in the direction of the field pole's direct axis and in the direction of the transverse axis. It is an eggplant. The number of poles of the field windings 3b and 4b of each of the second and third AC exciters whose output frequency is 6 nf with respect to the output frequency f of the three-phase synchronous generator 1 is the above-mentioned three-phase synchronization. It is selected to be 6n times the number of poles of the field winding 1b of the generator.

Reference numerals 6, 7 and 8 are first, second and third for supplying adjusted DC exciting currents to the field windings 2b, 3b and 4b of the first to third AC exciters, respectively. In the rotor unit 9 surrounded by the two-dot chain line, the three-phase synchronous generator commonly driven by the generator shaft 20 and the rotor of each AC exciter are included. . Next, FIG. 2 shows a second embodiment of the present invention according to claim 2 which is directed to the brushless synchronous generator shown in FIG. 1. The fixed field of each of the second and third AC exciters is shown in FIG. It is a perspective view showing an outline of a phase shifter as a stator frame drive means which changes the magnetic poles through the stator frame in the circumferential direction by a required angle.

Although FIG. 2 exemplifies the second AC exciter 3, the illustrated contents are the third AC exciter 4.
Can be similarly applied. In FIG. 2, reference numeral 3c denotes a stator frame of the second AC exciter 3, which is provided with a rotating bearing for a support arm fixed to the stator frame covering the entire main part of the brushless synchronous generator shown in FIG. It is rotatably supported, and as shown in the drawing, a partial gear is provided on a part of its outer circumference.

The fifteen phase shifters are the drive gear 1
5a, a drive motor 15b, and a coupling 15c. The drive motor 15b drives the drive gear 15a and the partial gears provided on the stator frame 3c, so that the stator frame 3c of the AC exciter 3 is driven. Is rotated in the circumferential direction by a required angle. FIG. 4 is a circuit diagram of a brushless synchronous generator including the above-described three-phase synchronous generator and each AC exciter, and shows a third embodiment of the present invention according to claims 4 and 5. This is a modification of the field windings 3b and 4b of the second AC exciter 3 and the third AC exciter 4 shown in the circuit diagram of FIG.

That is, the two field windings 3b and 4b are respectively arranged orthogonally to each other, and the field windings 11b and 11c for DC excitation are arranged.
And 12b and 12c are changed to a combination of two sets of field windings, and accordingly, the reference symbols of the second AC exciter, the third AC exciter, and the rotor section including them are respectively changed. 11 and 12 and 10. Here, the two field windings 11b and 11c are the second excitation adjusting device 13 for the DC exciting current adjusted so that the direction and the magnitude of the combined magnetic flux by the two sets of field windings become required values. It is supplied by. Similarly, the field windings 12b and 12c are also supplied with the adjusted DC exciting current from the third excitation adjusting device 14.

The direction of the combined magnetic flux is based on the phase of the fundamental wave voltage generated by the three-phase synchronous generator 1, and is the above (6n ± 1) in the AC system with which the synchronous generator 1 is linked. It is adjusted so that the f harmonic voltage component and the induced voltage due to the rotating magnetic field of the angular velocity corresponding to the frequency 6nf by the field windings 1c and 1d have opposite phases.
That is, the direction adjustment of the synthetic magnetic flux as described above electrically realizes the function of the phase shifter as the mechanical means shown in FIG.

Further, FIG. 5 shows the both field windings 11b and 11
It is a pair phase change figure of the magnetomotive force by two sets of field windings A and B which are orthogonally arranged like c and are excited by direct current. Now, if the DC exciting currents of the field windings A and B are respectively adjusted to appropriate values, it is possible to easily set the direction and magnitude of the combined magnetomotive force as the vector sum to the required values.

[0028]

According to the present invention, the first field winding for generating the magnetic flux for generating the fundamental wave voltage in the field pole of the rotating field type synchronous machine and the first field winding for generating the magnetic flux in the direction perpendicular to the field pole are provided. A field winding of No. 2 and a third field winding that generates a magnetic flux in the horizontal axis direction of the field pole are provided, and the frequency is 6 nf with respect to the frequency f of the fundamental wave.
By supplying a harmonic current of (n is a positive integer) to the field windings of the second and third coils and giving a predetermined phase difference between the harmonic currents of both, the field pole And a harmonic absorption synchronous machine configured to generate a rotating magnetic field having an angular velocity corresponding to the frequency of 6 nf. 1) According to the invention of claim 1, a rotary rectifying device is provided for the first field winding. Rotating armature type first AC exciter for supplying a required DC exciting current through the rotating armature type for supplying a harmonic current having a frequency of 6 nf to the second field winding. Second AC exciter, and a harmonic having a frequency of 6 nf with respect to the third field winding and having a predetermined phase difference from the harmonic current supplied to the second field winding. Third rotating armature type that supplies electric current
By providing the alternating current exciter of (1) and the field pole drive shaft of the synchronous machine in common, the slip ring and the brush for exchanging exciting current between the three-phase synchronous generator and each of the alternating current exciters are both provided. A brushless synchronous generator which is not required can be constructed. 2) As for the second and the third alternating-current exciters according to the invention of claim 2, the field poles of the two exciters are respectively changed. By providing stator frame drive means for independently changing the required angle in the circumferential direction through the stator frame, the harmonic voltage components in the AC system linked with the synchronous machine and the harmonics generated in the synchronous machine are provided. Phase adjustment can be performed so that the wave voltage has an opposite phase, and 3) the field winding of each of the second and third alternating-current exciters according to the invention of claim 3 DC excitation to supply power to By adjusting the flow, it becomes possible to make the harmonic voltage component in the AC system and the harmonic voltage generated in the synchronous machine substantially equal, and 4) claim 4 and claim 5 According to the invention of
With respect to the third and third alternating-current exciters, two sets of direct-current excitation field windings arranged orthogonally to the field poles of both exciters are provided.
Further, as a phase adjusting means between the harmonic voltage component in the AC system and the harmonic voltage generated in the synchronous machine, by making it possible to independently adjust the DC currents supplied to these field windings, respectively. Instead of the mechanical stator frame driving means according to the second aspect of the invention, the same function can be achieved by electrical means.

That is, with the above-mentioned structure,
A function to effectively eliminate or reduce harmonic components of a specific frequency in the AC system linked to the rotating field type synchronous machine,
In other words, it is possible to provide an effective absorption function, and by configuring the synchronous machine as a brushless type three-phase AC synchronous machine, the slip ring and the brush, which have been conventionally required, are not necessary and this is achieved. Complicated work such as maintenance and inspection and replacement work can be eliminated, and at the same time, operational reliability of the synchronous machine can be improved.

When the brushless AC synchronous machine as described above is viewed from the viewpoint of power transmission, the armature output of the final stage rotary field type synchronous machine and the control input of the excitation adjusting device for providing the excitation input of the AC exciter are used. The ratio of power amplification is very large,
This indicates that extremely various controls can be performed on the armature output of the synchronous machine according to the form of the control input of the excitation adjusting device.

Further, by providing the synchronous machine with the function of eliminating or reducing the AC system harmonics as described above, the size of the synchronous machine itself can be reduced as compared with the case where the inflow of the system harmonics is assumed. In addition, it can be used as a substitute device for an expensive active filter.

[Brief description of drawings]

FIG. 1 is a half sectional view of a main part of a brushless synchronous generator showing a first embodiment of the present invention.

FIG. 2 is a perspective view of a phase shifter showing a second embodiment of the present invention.

FIG. 3 is a circuit diagram of the brushless synchronous generator shown in FIG.

FIG. 4 is a circuit diagram of a brushless synchronous generator showing a third embodiment of the present invention.

FIG. 5 is a phase change diagram of a combined magnetomotive force by two sets of DC excitation magnetic field magnetic windings arranged orthogonally.

[Explanation of symbols]

 1 three-phase synchronous generator (rotary field fixed armature type) 1a armature winding of three-phase synchronous generator 1b first field winding of three-phase synchronous generator 1c second field of three-phase synchronous generator Winding 1d Third field winding of three-phase synchronous generator 2 First AC exciter (rotary armature fixed field type) 2a Armature winding of first AC exciter 2b Field of first AC exciter Winding 3 2nd alternating current exciter (rotary armature fixed field type) 3a 2nd alternating current exciter armature winding 3b 2nd alternating current exciter field winding 3c 2nd alternating current exciter stator frame 4 Third AC exciter (rotary armature fixed field type) 4a Third AC exciter armature winding 4b Third AC exciter field winding 5 Rotational rectifier 6-8 Excitation adjuster 9,10 Rotation Sub-unit 11 Second AC exciter (rotating armature fixed field type) 12 Third AC exciter (rotating armature fixed field type) 13, 14 Excitation adjustment Location 15a driven gear 15b drive motor 15c coupling 20 generator shaft

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kiyoshi Oku 3-3-22 Nakanoshima, Kita-ku, Osaka City Kansai Electric Power Co., Inc. No. 1 inside Fuji Electric Co., Ltd. (72) Inventor Atsushi Ashizawa 1-1, Tanabe Nitta, Kawasaki-ku, Kawasaki-shi, Kanagawa Inside Fuji Electric Co., Ltd.

Claims (5)

[Claims] 1. A first field winding for generating a magnetic flux for generating a fundamental wave voltage, and a second field magnetic field for generating a magnetic flux in a direction perpendicular to the field pole in a field pole of a rotary field synchronous machine. A winding and a third field winding that generates a magnetic flux in the horizontal direction of the field pole are provided, and a harmonic current having a frequency of 6 nf (n is a positive integer) with respect to the fundamental wave frequency f is supplied to the second and third fields. A harmonic wave configured to generate a rotating magnetic field having an angular velocity corresponding to the frequency of 6 nf on the field pole by energizing both field windings and providing a predetermined phase difference between the harmonic currents. In the absorption synchronous machine, a rotating armature-type first AC exciter for supplying a required DC exciting current to the first field winding through a rotary rectifier, and the second field magnet. Rotating armature type that feeds a harmonic current whose frequency is 6 nf to the winding A second AC exciter, and said third of said its frequency to field winding 6nf and the second
Of the rotating armature type third AC exciter for feeding a harmonic current having a predetermined phase difference from the harmonic current fed to the field winding of A brushless harmonic absorption synchronous machine characterized in that it is provided as. 2. The brushless harmonic absorption synchronous machine according to claim 1, wherein both the second and third alternating-current exciters include:
A brushless type harmonic absorption synchronous machine, characterized by comprising stator frame driving means for independently changing the field poles of both exciters through their respective stator frames in the circumferential direction by a required angle. 3. The brushless harmonic absorption synchronous machine according to claim 1, wherein both the second and third alternating-current exciters include:
A brushless harmonic absorption synchronous machine characterized in that the armature output current of each of the exciters can be independently adjusted by adjusting the DC exciting current supplied to each field winding. 4. The brushless harmonic absorption synchronous machine according to claim 1, wherein both the second and third alternating-current exciters include:
2. A brushless harmonic absorption synchronous machine comprising two sets of field windings for direct current excitation arranged orthogonally to each other on the field poles of both exciters. 5. The brushless type harmonic absorption synchronous machine according to claim 4, wherein the DC exciting currents supplied to the two sets of field windings for DC excitation arranged orthogonally to each other can be independently adjusted. A brushless harmonic absorption synchronous machine characterized by the above.