JPH1155912A - Cylindrical synchronous generator - Google Patents

Abstract

(57) [Summary] [Problem] Without being limited to the magnitude of the current in the negative phase,
A generator that can load more than a conventional generator is obtained. A three-phase four-pole main power generation winding (3) and a stator field winding (4) having twice the number of poles of the main power generation winding (3) are wound around a stator, and the stator field A rotor excitation winding 5 magnetically coupled to the magnetic winding 4 and a plurality of distributed rotor windings 7 short-circuited by a rectifier 8 in a concentrated winding of all sections are wound.
A rotor rectifier 6 for converting an electromotive force of the rotor excitation winding 5 into a direct current, and a rotor winding 7 of the plurality of rotor windings 7 which most contributes to a main field of a main power generation winding 3; And the output of the rotary rectifier 6 was connected to the rotor 10 to form the rotor 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a cylindrical synchronous generator corresponding to an unbalanced load.

[0002]

2. Description of the Related Art A generator has a series winding excitation function in a main body thereof.
As a brushless self-excited synchronous generator that outputs a voltage having a flat compound winding characteristic, a generator disclosed in Japanese Patent Application Laid-Open No. 3-245755 is known, and this brushless self-excited synchronous generator is shown in FIG.

The brushless self-excited synchronous generator disclosed in Japanese Patent Application Laid-Open No. 3-245755 has a two-pole (embodiment) main power generation winding having a winding form conforming to concentrated full winding or concentrated full winding on the stator core 20. U, V, W and 5 times the number of poles of the main power generation winding (Example)
(Example) stator field winding 21 having 10 poles
The rotor core 22 has two poles (example) of the rotor field winding 23 and the poles of the stator field winding having the same number of poles as the main power generation winding. Rotation of 10 poles (embodiment) having the same number of poles and magnetically coupling with the fifth spatial harmonic component (10-pole magnetic field) of the armature reaction magnetic field generated by the current of the main power generation winding. The main excitation windings 24 are wound, and the main power generation windings U, V, W and the stator field windings 21 are connected to intermediate taps u of respective phases of the main power generation windings U, V, W. , V, w connected via a control rectifier VR (a three-phase full-wave rectifier 25 and a variable resistor Rf), and the rotor excitation winding 24 and the rotor field winding 23 are Connected via a bridge circuit 26.

[0004] The operation of the brushless self-excited synchronous generator having this configuration will be described below. When the rotor is rotated, an electromotive force is induced in the main power generation windings U, V, W by the residual magnetism of the rotor core 22. This induced electromotive force is rectified by the three-phase full-wave rectifier 25 and the direct current Ifs is applied to the stator field winding 21.
And the alternating current flows through the main power generation winding, and the rotor excitation winding 24 has an electromotive force based on the static magnetic field generated by the DC current Ifs and the armature reaction magnetic field generated by the alternating current of the main power generation winding. The electromotive force based on the fifth harmonic component is superposed and induced, and the superimposed electromotive force is applied to the diode bridge circuit 26.
DC current If
Flows, and the main magnetic field is magnetized to increase the electromotive force of the main power generation winding. By repeating this operation, the output voltage is self-established. At this time, if the residual magnetism of the rotor core 22 is insufficient, the battery B is used to perform the initial excitation.

Further, in the brushless self-excited synchronous generator, when the load increases or decreases in a three-phase resistance and an inductive (lagging power factor) load, respectively, the fifth-order space of the armature reaction magnetic field increases in proportion to the increase or decrease of the load current. The harmonic component increases and decreases, and as a result, the DC current If of the rotor field winding 23 increases and decreases, thereby suppressing the fluctuation of the output voltage. As a result, an output voltage having a flat double winding characteristic can be obtained with respect to the increase and decrease of the load. When a three-phase unbalanced load or a single-phase load is connected to the generator, the series-wound excitation effect due to the fifth spatial harmonic component of the armature reaction magnetic field is reduced as compared with the three-phase balanced load. When a phase-unbalanced load or a single-phase load is applied, an electromotive force is induced in the rotor field winding 23 by the spatial fundamental wave component of the opposite phase of the armature reaction magnetic field, and the electromotive force is half-waved by the diode bridge circuit 26. The rotor field winding 23 is rectified and is based on the reduction of the series exciting effect.
Is compensated for, the output voltage at the time of a three-phase unbalanced load or a single-phase load also has a flat compound winding characteristic as at the time of a three-phase balanced load.

[0006]

In this brushless self-excited synchronous generator, when the load of the three-phase generator is a three-phase unbalanced load, the armature reaction for the positive phase component and the negative phase component is applied to the power generation winding. Generates a magnetic field. Of these, the positive-phase armature reaction magnetic field is the same as the armature reaction of the three-phase equilibrium current, and does not cause any problem. Although the electromotive force is induced in the magnetic winding and has a compensating effect, at the same time, a double frequency alternating current is induced in the field to distort the armature induced voltage, and an eddy current is induced in the rotor to heat the rotor. And other various adverse effects.

This is because the rotating magnetic field of the opposite phase interlinks with the field winding at a speed twice as fast as the synchronous speed, so that an AC voltage having twice the frequency is induced in the field winding. The field winding is considered to be a single-phase winding. Therefore, considering the combination of two vectors rotating in the opposite direction at the same speed as in the reaction of the armature winding, the magnetic flux increases the armature winding three times. Induces frequency voltage. When an AC of the third harmonic flows through the armature circuit, an AC voltage having a frequency four times higher is induced in the field winding by the magnetomotive force due to the same action as described above. If the harmonic current is allowed to flow freely, the armature winding induces a voltage, current, etc., which is 3 times, 5 times, 7 times, etc., in addition to the fundamental wave, thereby causing the field winding. The wires generate harmonic currents of 2, 4, 6, 8, etc. in addition to the direct current. This phenomenon is common to conventional three-phase generators with imperfect dampers.

[0008] The heating action of the rotor due to the eddy current generated in this way is difficult to overlook because there is a risk of causing an accident. It is said that the limit is about 15 to 25%.

As described above, since the generator of the present invention does not select any harmonic component of an arbitrary order, the number of slots and a combination thereof are limited to a specific number depending on the order of the selected harmonic component. The present invention provides a generator which is not limited by the magnitude of the current in the negative phase and is not limited by the magnitude of the current in the opposite phase, and can load a single-phase load, an inverter or the like which generates harmonics more than a conventional generator. That is the task.

[0010]

According to the first aspect of the present invention, the main power generation winding and a plurality of rotor windings distributed in a concentrated winding and short-circuited by a rectifier are distributed and wound. A cylindrical field that magnetically couples with the generator winding, a stator field winding, a rotor excitation winding that magnetically couples with the stator field winding,
And a rotary rectifier configured to convert the power output of the rotor excitation winding to DC. The output of the rotary rectifier is connected only to the rotor winding that most contributes to the field, and the other rotor winding is used as a means for solving the problem by a cylindrical synchronous generator having a damper winding. .

That is, a plurality of distributed rotor windings short-circuited by a rectifier in a concentrated winding of all sections are wound, and a main field of the number of poles of a main power generation winding among the plurality of rotor windings is wound. By connecting the output of the rotary rectifier only to the rotor winding that contributes the most, the single-phase load is not limited to the magnitude of the negative-sequence component current as in the conventional generator. And Invar
Also, a load that generates harmonics, such as power, can be loaded more than a conventional generator. In addition, when a load is applied, a half-wave rectified current by a diode flows through the main field winding and the damper winding, and the DC component increases the field.
And the loss is reduced.

Further, as compared with the conventional power generator, the rotor is cylindrical, and no major change is required. Therefore, the rotor can be easily applied to the conventional generator, and the cylindrical type can be used for the field winding. The wire and the damper winding can be arranged uniformly around the circumference, and the damper effect is completed.

According to a second aspect of the present invention, a stator is formed by winding a main power generation winding and a stator field winding having an even number of poles of the main power generation winding. A rotor excitation winding magnetically coupled with the stator field winding, a plurality of rotor windings distributed and short-circuited by a rectifier in a concentrated winding of all nodes, A rotating rectifier that converts the electromotive force of the rotor excitation winding into direct current, and only the rotor winding that most contributes to the main field of the number of poles of the main generator winding among the plurality of rotor windings. The output of the rotary rectifier was connected to form a cylindrical synchronous generator having a rotor.

[0014] With this configuration, the generator is wound with the main generator winding and the stator field winding around one stator,
The present invention can be applied to a relatively small synchronous generator having a configuration in which a main field winding and a rotor excitation winding are wound around one rotor.

According to a third aspect of the present invention, there is provided a cylindrical type in which a stator comprising a main power generation winding and a plurality of rotor windings distributed in a concentrated manner and short-circuited by a rectifier are wound around the stator. A cylindrical type in which a rotor and a power generating unit are configured, a stator including a stator field winding, and an exciting unit including a rotor exciting winding magnetically coupled to the stator field winding. A synchronous generator was used.

With this configuration, a relatively large generator can be configured, and a power generator is formed by a rotor having a main field winding wound on the same rotating shaft and a stator having a main power winding wound thereon. Further, an exciting unit is constituted by an exciter rotor around which a rotor exciting winding for exciting the main field is wound and a stator around which a stator field winding is wound. Even if the configuration is almost the same as a conventional large generator in which the field winding and the rotor excitation winding of the excitation unit are connected by a rotary rectifier, unbalanced loads and harmonics that were not sufficient in the past are generated. The generator is capable of responding to the changing load.

According to the fourth aspect, the rotor winding connected to the output of the rotary rectifier and contributing to the main field of the number of poles of the main power generation winding is connected in series according to the output characteristics of the rotor excitation winding. Or, since they can be connected in parallel, the rotor winding and the rotor excitation winding can be freely connected according to the output characteristics of the rotor excitation winding, so that the rotor excitation winding is independent of the rotor winding. The wires work effectively and do not degrade the generator output characteristics.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A synchronous generator 1 according to the present invention will be described below by way of example with a three-phase specification. In the first embodiment, as shown in FIG. 1, a stator 2 has a three-phase four-pole main power generation winding 3 and an eight-pole stator field winding 4 which is an even multiple of the number of poles of the main power generation winding 3.
Is wound. The rotor 10 has a three-phase eight-pole rotor excitation winding 5 magnetically coupled to the stator field winding 4.
And a plurality of main field windings 7 and damper windings 9 having the same number of poles as the main power generation winding 3 are wound, and each of the windings is short-circuited by a diode 8. And a rotary rectifier 6 for converting the electromotive force of the rotor excitation winding 5 into a direct current. The output of the rotary rectifier 6 is applied only to the main field winding 7 that contributes to the main field of the rotor 10. Provided. Here, all of the plurality of main field windings 7 and damper windings 9 are formed in a cylindrical rotor as shown in FIG. In other words, a plurality of windings are wound around all the slots of the rotor by concentrated winding of all the sections, and the windings contribute to the main magnetic field (the windings are wound substantially perpendicular to the main magnetic field). The main field winding 7 is divided into a damper winding 9 (wound in the same direction as the main magnetic field) at the center of the magnetic pole, and the output of the rotary rectifier 6 is supplied to the main field winding 7. I have to do it. Here, the whole section concentrated winding means, for example, based on the number of poles of the main power generation winding 3,
This means that the coil pitch between the main field winding 7 and the damper winding 9 wound on the rotor is set to the electrical angle π. An arbitrary DC power supply 11 is connected to the stator field winding 4.

In the example shown in FIG. 2, the main field windings 7 that contribute to the main field are W1, W2, W3 and W4, and W5 and W6 are used as damper windings 9. W1,
W2, W3 and W4 are connected by W1 and W2 and W3 and W4.
Are connected in series with each other, and the outputs of the rotary rectifier 6 are connected by connecting them in parallel. These series and parallel connections are not limited to this example, and the connection form differs depending on the output characteristics of the rotor excitation winding 5.

FIG. 3 shows an example of a winding arrangement of the main field winding 7, the damper winding 9, and the rotor excitation winding 5 of the rotor by developing the rotor core in a plane. Referring to FIG. 2, an example of a rotor having 24 slots is shown, in which the main field winding 7 is arranged in 4 slots, and then the damper winding 9 is connected to 2 slots.
Placed in slots. The case where the rotor excitation winding 5 has three phases and eight poles is shown, and each of the three phases is shown by changing the shape of the conductor. Note that the present invention can be implemented with a single phase, so that the rotor mode is not limited to FIG.

[0021]

FIG. 1 shows an operation state under a normal three-phase balanced load.
This will be described below. When a rotor is rotated by a prime mover (not shown) and a DC power supply 11 is connected to the stator field winding 4 to flow a DC current, an 8-pole magnetic field is formed on the stator and the rotor core, and the rotor is rotated. An electromotive force is generated in the exciting winding 5 and a compensating current flows, and is converted into DC by the rotary rectifier 6, and a DC current flows in the main field winding 7 to generate a four-pole field magnetic flux, thereby generating a main power generating winding. An electromotive force is generated in the line 3 to supply power to the load 12.

Here, it is proved that no current flows through the diode 8 which short-circuits the main field winding 7 and the damper winding 9 by the eight-pole magnetic field formed by the stator field winding 4. . That is, as shown in FIG. 4, the fundamental wave of the eight-pole static magnetic field formed by the stator field winding 4 is added to the rotor 10.
When the four-pole main field winding 7 and the damper winding 9 wound on each other are linked by rotation, e1, e2, e3 are added to the conductors of the windings.
And the voltage of e4 is induced, and the sum of the voltages, that is, the voltage V applied to the diode 8, becomes zero as shown in the equation (1).

[0023]

(Equation 1) Accordingly, the diode 8 does not fire and the generator of the present invention operates similarly to a conventional generator. Since the stator field winding 4 and the rotor excitation winding 5 have the same power amplifying action as the conventional exciter, there is an advantage that the capacity of the AVR (automatic voltage regulator) can be reduced.

Next, the operation and effect of the generator according to the present invention when a single-phase load is mixed with a three-phase load and becomes a three-phase unbalanced load will be described. That is, when a three-phase unbalanced load is applied to the generator 1, a negative-phase current flows through the main generator winding 3. Due to the negative phase current, the main power generation winding 3 generates a four-pole negative phase rotating magnetic field, which is wound around the rotor 10 because the negative phase rotating magnetic field rotates in a direction opposite to the rotating direction of the rotor 10. A voltage is induced in the main field winding 7 and the damper winding 9. How the diode 8 acts on this induced voltage will be described.

As shown in FIG. 5, when the four-pole main field winding 7 and the damper winding 9 wound around the rotor 10 interlink with the anti-phase rotating magnetic field, e1,, The voltages of e2, e3 and e4 are induced, and the sum of them, that is, the voltage V applied to the diode 8 becomes 4E 'as shown in the equation (2). Therefore, a half-wave rectified current flows through the winding through the diode 8 by the voltage of 4E '.

[0026]

(Equation 2) This half-wave rectified current can be decomposed into a DC component and an AC component, and the DC component is superimposed on the DC output current of the rotary rectifier 6, and this phenomenon that acts to increase the field current will be described in further detail. As shown in FIG. 6 (a), the DC output current I1 of the rotary rectifier 6 flows through the W of the main field winding 7 and does not flow to the diode 8 because it has the opposite polarity. The DC component I2 in the half-wave rectified current flowing through the diode 8 due to the AC voltage e induced in the W of the main field winding 7 by the reversed-phase rotating magnetic field.
Flows according to the polarity of the diode 8 as shown in FIG. Therefore, as shown in FIG. 6 (c), I1 and I2 are superimposed to become (I1 + I2), which acts to increase the field current.

The AC voltage e induced in the damper winding 9
The DC component in the half-wave rectified current flowing through the diode 8 flows as shown in FIG. 6B depending on the polarity of the diode 8, and the magnetomotive force of the damper winding 9 due to this DC current is as shown in FIG. Has the effect of increasing the field flux. If the increase of the field magnetic flux is too large to cause a short circuit in the damper winding 9 due to the diode 8, a part or all of the short circuit may be a simple short circuit without using the diode 8.

As described above, when the reverse phase current increases, the output voltage of the generator 1 increases. However, the generator voltage is maintained at the rated voltage by the AVR, and as a result, the current flowing through the stator field winding 4 is reduced by the AVR. This means that the excitation power supplied via the AVR is reduced, which reduces generator losses and improves efficiency.

On the other hand, since the alternating current component of the half-wave rectified current by the diode 8 has a multi-phase winding of the main field winding 7 and the damper winding 9, the magnetic flux formed by them is in the opposite phase. It will act to cancel the rotating magnetic field. That is, the main field winding 7 and the damper winding 9 all act as a damper. This is the same as the principle of the induction motor. In short, the reversed-phase rotating magnetic field is absorbed by the main field winding 7 and the damper winding 9 by the action of the diode and is converted into a field current, thereby performing a magnetizing action.

Next, the operation and effect of the generator of the present invention when a load including a harmonic current such as an inverter is connected will be described. Since the magnetic field generated by the main power generation winding 3 by the harmonic current is a time harmonic, e1, e2, e3 in FIG.
And e4 are as follows:

[0031]

(Equation 3) Therefore, the voltage V applied to the diode is as follows.

[0032]

(Equation 4) That is, the magnitude of the voltage V is 4E "and the diode 8
Through which a half-wave rectified current flows. Therefore, even when a harmonic current flows in the main power generation winding 3, the diode 8 causes the main field winding 7 and the damper winding 9 to function as a damper and a magnetizer.

Next, as a second embodiment, FIG. 8 shows a case where the present invention is applied to a large generator. In the description, the same reference numerals are given to components having the same operation as the first embodiment regardless of the size of the components.

Reference numeral 14 denotes a power generation unit, in which a three-phase four-pole main power generation winding 3 is wound on the stator side, and a plurality of main fields having the same number of poles as the main power generation winding 3 are mounted on the rotor side. A magnetic winding 7 and a damper winding 9 are wound, and each winding is short-circuited by a diode 8. Reference numeral 15 denotes an excitation unit, on which a stator field winding 4 is wound on the stator side, and a three-phase rotation which magnetically couples with the stator field winding 4 on the rotor side. Child excitation winding 5
And a rotary rectifier 6 for converting the electromotive force of the rotor excitation winding 5 into DC. Excitation unit 1
5, the output of the rotary rectifier 6 on the rotor side is provided only to the main field winding 7 that contributes to the main field on the rotor side of the power generation unit 14.

Here, the plurality of main field windings 7 and the damper windings 9 are all formed by concentrated winding of all sections to form a cylindrical rotor as shown in FIG. In other words, a plurality of windings are wound around all the slots of the rotor by concentrated winding of all the sections, and the windings contribute to the main magnetic field (the windings are wound substantially perpendicular to the main magnetic field). The main field winding 7 is divided into a damper winding 9 (wound in the same direction as the main magnetic field) at the center of the magnetic pole, and the output of the rotary rectifier 6 is supplied to the main field winding 7. I have to do it. Here, the whole-section concentrated winding means, for example, that the coil pitch of the main field winding 7 and the damper winding 9 wound on the rotor is an electrical angle π based on the number of poles of the main power generation winding 3. Pointing to. An arbitrary DC power source 1 is connected to the stator field winding 4.
1 is connected. In the case of the present embodiment, the number of magnetic poles of the power generation unit 14 and the exciting unit 15 does not interfere with each other, and the number of magnetic poles is different from the number of magnetic poles as in the relationship between the main field winding and the rotor exciting winding of the first embodiment. It is not limited.

The operation of the cylindrical synchronous generator constructed as described above according to the present invention is the same as that of the first embodiment. Therefore, the present invention can be applied to a generator having a small output to a large output. Therefore, the range of application can be sufficiently expanded for unbalanced loads and loads that generate harmonics.

[0037]

As described above, according to the first aspect, the generator according to the present invention does not limit the single-phase load to the magnitude of the reverse-phase current as in the conventional generator. Loads that generate harmonics, such as loads and inverters, can also be loaded more than conventional generators. In addition, when a load is applied, a half-wave rectified current flows from the diode to the main field winding and the damper winding, and the DC component increases the field, so that the excitation power by the AVR is reduced and the loss is reduced.

According to the second aspect of the present invention, the generator is wound with the main generator winding and the stator field winding around one stator, and the main field winding is wound around one rotor. The present invention can be applied to a relatively small synchronous generator having a configuration in which a wire and a rotor excitation winding are wound.

According to the third aspect of the present invention, a relatively large generator can be configured by this configuration, and a rotor having a main field winding wound on the same rotating shaft and a stator having a main generator winding wound thereon. An exciter is constructed by an exciter rotor wound with a rotor exciting winding for exciting the main field and a stator wound with a stator field winding. The unbalanced load, which was not sufficient in the past, even though the configuration was almost the same as that of the conventional large generator in which the main field winding of the power generation unit and the rotor excitation winding of the excitation unit were connected by a rotary rectifier. And a generator that can sufficiently handle loads that generate high harmonics.

According to the fourth aspect, since the rotor winding and the rotor excitation winding can be freely connected in accordance with the output characteristics of the rotor excitation winding, the rotor excitation winding is independent of the rotor winding. Works effectively and does not lower the generator output characteristics.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a synchronous generator according to the present invention.

FIG. 2 shows a plurality of distributed rotor windings.

FIG. 3 is an expanded view of a rotor slot.

FIG. 4 is a diagram showing induced voltages of a main field winding and a damper winding during normal operation.

FIG. 5 is a diagram showing induced voltages of a main field winding and a damper winding under an unbalanced load.

FIG. 6 shows a diode in which the main field winding and the damper winding are short-circuited.
FIG. 4 is a diagram showing the magnetizing action of

FIG. 7 is a diagram showing a magnetomotive force distribution of a main field winding and a damper winding.

FIG. 8 is a diagram showing another embodiment of the present invention.

FIG. 9 is a diagram showing a circuit diagram of a conventional synchronous generator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Three-phase cylindrical synchronous generator 2 Stator 3 Three-phase four-pole main generator winding 4 Stator field winding 5 Rotor excitation winding 6 Rotary rectifier 7 Main field winding 8 Diode 9 Damper winding DESCRIPTION OF SYMBOLS 10 Rotor 11 DC power supply 12 Load 13 Three-phase cylindrical synchronous generator 14 Power generation part 15 Excitation part 20 Stator core 21 Stator field winding 22 Rotor core 23 Rotor field winding 24 Rotor excitation winding 25 Three-phase full-wave rectifier 26 Diode bridge circuit

Claims (4)

[Claims] 1. A cylindrical field which magnetically couples with a main power generation winding and a plurality of rotor windings distributed in a concentrated winding and short-circuited by a rectifier. A stator field winding, a rotor excitation winding magnetically coupled to the stator field winding, and a rotary rectifier for converting the power output of the rotor excitation winding to DC. The synchronous rectifier, wherein the output of the rotary rectifier is connected only to the rotor winding that most contributes to the main field of the number of poles of the main generator winding among the plurality of rotor windings. A cylindrical synchronous generator characterized in that another rotor winding is a damper winding. 2. A stator is formed by winding a main generator winding and a stator field winding having an even number of poles of the main generator winding. A rotor excitation winding magnetically coupled to a wire, and a plurality of rotor windings distributed by short-circuiting with a rectifier in a concentrated winding of all sections are wound. A rotary rectifier for converting an electromotive force into direct current, and connecting an output of the rotary rectifier only to a rotor winding that most contributes to a main field of the number of poles of a main generator winding among the plurality of rotor windings. 2. The cylindrical synchronous generator according to claim 1, wherein the rotor is formed as a rotor. 3. A power generation unit comprising: a stator comprising a main power generation winding; and a cylindrical rotor in which a plurality of rotor windings distributed in a concentrated winding and short-circuited by a rectifier are wound. 2. An exciting unit comprising: a stator comprising a stator field winding; and a rotor excitation winding magnetically coupled to the stator field winding. Cylindrical synchronous generator. 4. A rotor winding connected to the output of the rotary rectifier and contributing to the main field of the number of poles of the main generator winding is connected in series or in parallel according to the output characteristics of the rotor excitation winding. The cylindrical synchronous generator according to claim 2 or 3, wherein: