JP2004072985A - Ac generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an AC generator which allows the use of a three-phase AC power supply and a single-phase three-wire AC power supply at the same time, and in which an output voltage is set freely and, in particular, voltage specifications facilitate an adaptability to versatile overseas situations. <P>SOLUTION: The AC generator has a stator in which three armature windings (a), (b), and (c) wound from a starting end to a termination are wound in Y-connection with the same number of turns and 120° of phase difference to each other. The respective starting ends are connected to a neutral point O, and three-phase output terminals R, S and T are connected to the respective terminations. The features of the AC generator is that, for example, (a), (b) among the three armature windings (a), (b), and (c) includes taps H1, H2 disposed at a fixed position between the starting end and the termination (in Fig.1, situated at an intermediate point close to the termination side and at a position at which the number of turns is equal), and armature extension windings d1, d2 in which the terminals on one side are connected to the taps H1, H2, whereas the terminals on the other side serve as single-phase output terminals, respectively. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an alternator, and more particularly to an alternator power supply.
[0002]
[Prior art]
This type of alternator has a 200V three-phase power source for lighting and electric appliances in addition to a 200V three-phase power source for power used in construction sites and various event venues. Is often required. In order to meet such a demand, for example, a conventional power generator as shown in FIGS. 10 to 12 is disclosed in Japanese Patent Application Laid-Open No. 63-87157.
[0003]
That is, in FIG. 10, the conventional example is, for example, an armature among three-phase stators composed of armature windings U, V, and W connected to the neutral point O with a phase difference of 120 degrees (electric angle) from each other. The winding W is divided into two equal parts, W1 and W2, and not only the armature windings W1 and W2 are connected in series, but also the armature winding W1 is set to the opposite phase (shown by a broken line) and the neutral point O is set. And a connection switching device (not shown) for connecting to the device. When the armature windings W1 and W2 are connected in series by the switching operation of the connection switching device, the armature windings W1 and W2 can be used as a three-phase power supply, and the terminals L1, L2, and L3 are connected as shown in the voltage vector of FIG. Output 200V three-phase AC power.
[0004]
On the other hand, when only the armature winding W1 is brought into the opposite phase and connected to the neutral point O by the switching operation of the connection switching device (not shown), as shown in the voltage vector of FIG. It can be used as a three-phase three-wire power supply. A single-phase AC power of 100 V is supplied between the terminals L1 and N and between the terminals L2 and N, and a single-phase AC power of 200 V is supplied between the terminals L1 and L2. Is output. By the way, as shown in FIG. 10, a neutral point O is connected to ground lines Le and Le 'and a neutral line having a neutral terminal N, respectively, and the ground line is connected to the ground. At the same time as switching to the power supply, the ground line Le is cut off, the ground line Le 'is connected to the neutral terminal N, and the ground is grounded via this ground line.
[0005]
[Problems to be solved by the invention]
However, the conventional example has the following problem.
[0006]
{Circle around (1)} The connection switching device of the conventional example requires a changeover switch having a contact capacity that can tolerate the amount of power to be output. As a result, not only costs are increased, but also electrical wiring becomes complicated.
[0007]
{Circle around (2)} When a single-phase three-wire power supply is configured in the conventional example, the voltage of the armature winding in the opposite phase appears at the terminal N of the neutral wire of the single-phase three-wire power supply, that is, at the neutral terminal. The property of the neutral point that is the same potential as that of the neutral point is lost. Therefore, switching of the connection of the ground line Le from the neutral point O to the terminal N is performed, which adds to the problem (1).
[0008]
{Circle around (3)} In the conventional example, the AC power of the three-phase power supply and the single-phase three-wire power supply cannot be output simultaneously, and the utilization rate of the AC generator is reduced.
[0009]
{Circle around (4)} In the conventional example, since the armature winding of the three-phase power supply is separated into two and switched to be a single-phase three-wire power supply, the number of turns of the armature winding of the single-phase three-wire power supply is reduced. As a result of depending on the number of turns of the armature windings of the three-phase power supply, the output voltage of the single-phase three-wire power supply cannot be freely set from the three-phase power supply, and it is particularly difficult to respond to overseas situations with various voltage specifications. I have to.
[0010]
Therefore, an object of the present invention is to provide a high utilization factor that can simultaneously output AC power of a three-phase power supply and a single-phase three-wire power supply without requiring a changeover switch. The number of turns does not depend on the number of turns of the armature windings of the three-phase power supply, and the output voltage of the single-phase three-wire power supply can be set freely from the three-phase power supply.Especially, it is easy to respond to overseas situations with various voltage specifications. It is an object of the present invention to provide an alternator which can be used.
[0011]
[Means for Solving the Problems]
The invention according to claim 1 of the present invention that solves the above problem is an AC generator having a three-phase power supply that outputs three-phase AC power, and a single-phase three-wire power supply that outputs single-phase AC power. In the three-phase power supply, three armature windings (a, b, c) wound from a winding start end to a winding end connected to a neutral point have the same number of turns and a phase difference of 120 degrees from each other. And the two armature windings (a, b) of the three armature windings have the same number of turns from the winding start end on the neutral point side. And tap portions (H1, H2) are respectively provided at positions of the two armature windings (a, b) between the tap portions (H1, H2) and the neutral point. (H1, h2), and the armature extension winding (d1) having half the number of turns of a part (h1, h2) of the two armature windings. d2) is connected to extend to the tap portion so as to be in phase with the remaining armature windings (c) other than the two armature windings. Each of d2) is connected to a part (h1, h2) of the two armature windings (a, b) via the tap portion (H1, H2) together with the neutral point. An alternator characterized by comprising a single-phase three-wire power supply.
[0012]
Also, in the invention according to claim 2, the predetermined position of each of the tap portions is a terminal on the winding end side, whereby the two armature windings (a, b) are partially provided. (H1, h2), and each of the armature extension windings (d1, d2) is connected to the two armature windings (a, h2) via tap portions (H1, H2) located at the terminals. 2. The alternator according to claim 1, wherein the single-phase three-wire power supply is configured as a result of being connected with b) and the neutral point.
[0013]
Further, the invention according to claim 3 is an AC generator having a three-phase power supply that outputs three-phase AC power, and a single-phase three-wire power supply that outputs single-phase AC power, wherein the three-phase power supply is The three armature windings (a, b, c) wound from the winding start end to the winding end connected to the neutral point have the same number of turns and a phase difference of 120 degrees (electrical angle) from each other. A tap is provided at a predetermined position having the same number of turns from the neutral point side winding start end to each of two (a, b) of the three armature windings. Parts (H3, H4) are provided, respectively, between the tap part (H3, H4) and the neutral point, and a part of the two armature windings (a, b) is (h3 , H4), and the armature extension windings (d3, d4) having the same number of turns as part (h3, h4) of the two armature windings The (d3) is connected to the tap portion H3 so that the phase is electrically opposite to the armature winding b, and the (d4) is electrically opposite to the armature winding a. The taps are connected to the tap portion H4 so that the two armature windings (d3, d4) extend through the tap portions (H3, H4). The alternator is characterized in that the single-phase three-wire power supply is configured as a result of being connected together with a part (h3, h4) of (a, b) and the neutral point.
[0014]
In addition, in the invention according to claim 4, the predetermined position of each of the tap portions (H3, H4) is a position that bisects the number of turns of the two armature windings (a, b), Thereby, each of the armature extension windings (d3, d4) is connected to the two armature windings (a, b) via the tap portions (H3, H4) together with the neutral point. 4. The alternator according to claim 3, wherein the result is that the single-phase three-wire power supply is configured.
[0015]
According to the present invention, the three-phase power supply and the single-phase three-wire power supply always operate so that the outputs are simultaneously generated. As a result, there is no need to switch between the three-phase power supply and the single-phase three-wire power supply, and the utilization efficiency increases.
[0016]
In addition, the tap portion can be freely set at a predetermined position, and as a result, the output voltage can be set freely, and it is particularly easy to deal with overseas situations where the voltage specifications are various.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, with reference to the drawings, details of an AC generator according to an embodiment of the present invention will be described.
[0018]
FIG. 1 is a circuit diagram of an AC generator according to a first embodiment of the present invention, which is an example according to claim 1. FIG. 2 is a vector diagram showing a relationship between voltages generated in each armature winding when the AC generator shown in FIG. 1 is driven.
[0020]
In the alternator shown in FIG. 1, three armature windings a, b, and c wound from the winding start end to the winding end connected to the neutral point O have the same number of turns and a phase difference of 120 degrees from each other. It has a Y-connected stator and constitutes a three-phase power supply. A neutral line Le is connected to the neutral point O as necessary.
[0021]
A feature of this AC generator is that, among the three armature windings a, b, and c, a, b has a predetermined position from the winding start end, that is, the neutral point O to the winding end (in FIG. Taps H1 and H2 disposed at an intermediate point near the terminal end and having the same number of turns), one terminal is connected to the taps H1 and H2, and the other terminal L1 and L2 is simply connected. Armature extension windings d1 and d2 serving as phase output terminals. The armature extension windings d1 and d2 have half the number of turns of the armature windings h1 and h2, and are illustrated in FIG. 2 by voltage vectors Ed1 and Ed2. In FIG. 1, the armature winding c (in FIG. (Illustrated by the vector Ec).
[0022]
Referring to FIG. 2, when this AC generator is driven, three-phase voltage vectors Ea, Eb, and Ec are generated, and terminals R and S, terminals S and T, and terminals TU and U are generated. Generates a voltage vector Eab, a voltage vector Ebc (not shown), and a voltage vector Eca (not shown) represented by broken lines as combined vectors between adjacent phases.
[0023]
On the other hand, Ed1 and Ed2 having the same phase as voltage vector Ec are generated in armature extending windings d1 and d2, respectively. Further, a voltage vector Eh1 having the same phase as the voltage vector Ea is generated in the armature winding h1, and a voltage vector Eh2 having the same phase as the voltage vector Eb is generated in the armature winding h2. The magnitude of each vector is
2 | Ed1 | = 2 | Ed2 | = | Eh1 | = | Eh2 |
There is a relationship. From these vector calculations, it is derived that the voltage vector E1 of the composite vector of the voltage vectors Ed1 and Eh1 is equal to E2, and the magnitude of E3 is twice the magnitude of E1 or E2. That is, voltage vectors E1, E2, and E3 are output from terminals L1, L2, and neutral point O as single-phase AC power of a single-phase three-wire power supply.
[0024]
The predetermined positions of the tap portions H1 and H2 are set at desired positions without depending on the voltage vectors Eab, Ebc (not shown) and Eca (not shown) of the armature windings of the three-phase power supply. can do.
[0025]
FIG. 3 is a circuit diagram of an AC generator according to a second embodiment of the present invention. FIG. 4 is a vector diagram showing a relationship between voltages generated in each armature winding when the AC generator shown in FIG. 3 is driven.
[0026]
The AC generator of FIG. 3 is characterized in that the predetermined position of the tap portion H1 is the same position as the terminal R. If the magnitude of the voltage vector Eab in FIG. 4 is set to 200 V, three-phase AC power of 200 V is output from the terminals R, S, and T in FIG. 3, and at the same time, between the terminal L1 and the neutral point O and between the terminals L2 and L2. A single-phase AC power of 100 V is output from between the neutral points O, and a single-phase AC power of 200 V is output from between the terminals L1 and L2.
[0027]
FIG. 5 is a circuit diagram of an AC generator according to a third embodiment of the present invention. An MCCB (interruption circuit breaker) for overcurrent protection is interposed between the terminals R, S, T and the armature windings a, b, c. The MCCB is for opening and closing a circuit that is a power path, and the voltage vector shown in FIG. 2 or FIG. 4 is not affected at all by the presence or absence of the MCCB. Therefore, the MCCB can be provided at a necessary place within the range of the conventionally known technique.
This situation is the same in the following embodiments.
[0028]
FIG. 6 is a circuit diagram of an AC generator according to a fourth embodiment of the present invention. FIG. 7 is a vector diagram showing a relationship between voltages generated in each armature winding when the AC generator of FIG. 6 is driven.
[0029]
In the alternator shown in FIG. 6, three armature windings a, b, and c wound from the winding start end to the winding end connected to the neutral point O have the same number of turns and a phase difference of 120 degrees from each other. It has a Y-connected stator and constitutes a three-phase power supply. A neutral line Le is connected to the neutral point O as necessary.
[0030]
The feature of this AC generator is that, among the three armature windings a, b, and c, a, b has a predetermined position from the winding start end, that is, the neutral point O to the winding end (in FIG. The taps H3, H4 disposed at an intermediate point near the starting end and having the same number of turns), one terminal is connected to the taps H3, H4, and the other terminal L1, L2 is simply connected. Armature extension windings d3 and d4 each serving as a phase output terminal. The armature windings h3 and d3 have the same number of turns, and the armature windings h4 and d4 have the same number of turns. is there. The armature extension windings d3 and d4 are characterized in that they are electrically connected in opposite phases to the armature windings a and b.
[0031]
Referring to FIG. 7, a voltage vector Ed3 having a phase opposite to voltage vector Eb is generated in armature winding d3, and a voltage vector Ed4 having a phase opposite to voltage vector Ea is generated in armature winding d4. Occurs. Further, a voltage vector Eh3 having the same phase as the voltage vector Ea is generated in the armature winding h3, and a voltage vector Eh4 having the same phase as the voltage vector Eb is generated in the armature winding h4. | Ed3 | = | Ed4 | = | Eh3 | = | Eh4 |
There is a relationship. From these vector operations, it is derived that the voltage vector E1 of the composite vector of the voltage vectors Ed3 and Eh3 is equal to E2, and the magnitude of E3 is twice the magnitude of E1 or E2. That is, voltage vectors E1, E2, and E3 are output from terminals L1, L2, and neutral point O as single-phase AC power of a single-phase three-wire power supply.
[0032]
Further, by changing the positions of the tap portions H3 and H4, the magnitudes of the voltage vectors E1, E2, E3 of the single-phase three-wire power supply are changed to the voltage vectors Eab, Ebc (not shown), Eca (not shown) of the three-phase power supply. ) Can be set independently to a desired value.
[0033]
FIG. 8 is a circuit diagram of an AC generator according to a fifth embodiment of the present invention, which is an embodiment according to claim 4. FIG. 9 is a vector diagram showing a relationship between voltages generated in each armature winding when the AC generator of FIG. 8 is driven.
[0034]
FIG. 8 shows an example in which the tap portion H3 of FIG. 6 is provided at a position where the number of turns of the armature winding a is bisected, and the tap portion H4 is provided at a position where the number of turns of the armature winding b is bisected. . Referring to FIG. 9, the magnitudes of voltage vectors Eab, Ebc (not shown), and Eca (not shown) between terminals R and S, between terminals S and T, and between terminals T and R are set to 200 V. As a result, as shown in FIG. 8, three-phase AC power of 200 V is output from terminals R, S, and T, and at the same time, 100 V is applied between terminals L1 and neutral point O and between terminals L2 and neutral point O. Single-phase AC power is output, and 200-V single-phase AC power is output from between the terminals L1 and L2.
[0035]
As described above, in the above-described embodiment, the voltage vector is limited to 200 V and 100 V. However, the present invention is not limited to these, and various modifications can be considered.
[0036]
For example, a plurality of combinations of tap portions and extended windings may be provided at predetermined positions of the armature windings a, b, and c to obtain a desired output voltage.
[0037]
【The invention's effect】
According to the present invention, since a three-phase power supply and a single-phase three-wire power supply are configured from the beginning, a switch for switching between the two power supplies in the conventional example is not required, and the power supply for both power supplies is not required. Since the characteristic point and the ground line are common, a changeover switch for this is not required. Therefore, electric wiring is significantly simplified, and there is an effect of cost reduction.
[0038]
In addition, it responds to the on-site demand for simultaneously outputting three-phase AC power from a three-phase power supply and single-phase AC power from a single-phase three-wire power supply, that is, always using the three-phase and single-phase outputs simultaneously. be able to. As a result, the effect of increasing the use efficiency can be expected.
[0039]
Further, the tap portion can be set to a predetermined position freely, and the armature extension winding is connected to the desired armature winding so as to extend in the same phase or in the opposite phase. As a result, the output of the single-phase three-wire power supply Since the voltage can be freely set independently of the output voltage of the three-phase power supply, an effect that the voltage specification can easily be adapted to various overseas situations can be expected.
[Brief description of the drawings]
FIG. 1 is a circuit diagram of an AC generator according to a first embodiment of the present invention.
FIG. 2 is a vector diagram showing a relationship between voltages generated in each armature winding when the AC generator of FIG. 1 is driven.
FIG. 3 is a circuit diagram of an AC generator according to a second embodiment of the present invention.
FIG. 4 is a vector diagram showing a relationship between voltages generated in each armature winding when the AC generator shown in FIG. 3 is driven.
FIG. 5 is a circuit diagram of an AC generator according to a third embodiment of the present invention.
FIG. 6 is a circuit diagram of an AC generator according to a fourth embodiment of the present invention.
FIG. 7 is a vector diagram showing a relationship between voltages generated in each armature winding when the AC generator of FIG. 6 is driven.
FIG. 8 is a circuit diagram of an AC generator according to a fifth embodiment of the present invention.
9 is a vector diagram showing a relationship between voltages generated in each armature winding when the AC generator of FIG. 8 is driven.
FIG. 10 is a circuit diagram of a conventional example of an AC generator.
11 is a diagram showing a case where the AC generator is driven when W1 and W2 (two voltage vectors in the same direction (leftward) represented by solid lines) are connected in series in the circuit of the AC generator of FIG. 10; FIG. 4 is a vector diagram showing a relationship between voltages generated in each armature winding.
12 is a diagram illustrating a relationship between voltages generated in armature windings when the AC generator is driven, when only W1 is connected in the opposite phase (the rightward voltage vector of the broken line) in the circuit of the AC generator in FIG. FIG. 14 is another vector diagram showing
[Explanation of symbols]
a, b, and c Armature windings Ea, Eb, Ec Voltage vector H1, H2 Tap portion Le Ground line O Neutral point d1, d2 Armature extension winding Eab Synthesis between adjacent phases between terminals R and S vector

Claims (4)

An AC generator having a three-phase power supply that outputs three-phase AC power, and a single-phase three-wire power supply that outputs single-phase AC power,
In the three-phase power supply, three armature windings (a, b, c) wound from a winding start end to a winding end connected to a neutral point have the same number of turns and are 120 degrees (electrical angle) from each other. It is configured to be Y-connected to the neutral point by a phase difference,
Of the three armature windings, two (a, b) are provided with tap portions (H1, H2) at predetermined positions having the same number of windings from the winding start end on the neutral point side, respectively. And
A part of the two armature windings (a, b) between the tap portion (H1, H2) and the neutral point is (h1, h2);
The armature extension windings (d1, d2) having half the number of turns of a part (h1, h2) of the two armature windings are electrically connected to the remaining armature windings (c) other than the two. Are connected to extend to the tap portion so as to be in phase with each other,
Thereby, each of the armature extension windings (d1, d2) is part (h1, h2) of the two armature windings (a, b) via the tap portions (H1, H2). Wherein the single-phase three-wire power supply is configured as a result of being connected together with the neutral point. Each predetermined position of the tap portion is a terminal on the winding end side,
Thereby, the two armature windings (a, b) become the same as part (h1, h2), and each of the armature extension windings (d1, d2) is a tap located at the terminal. The single-phase three-wire power supply is configured as a result of being connected to the two armature windings (a, b) via the sections (H1, H2) together with the neutral point. Item 7. The alternator according to Item 1. An AC generator having a three-phase power supply that outputs three-phase AC power, and a single-phase three-wire power supply that outputs single-phase AC power,
In the three-phase power supply, three armature windings (a, b, c) wound from a winding start end to a winding end connected to a neutral point have the same number of turns and are 120 degrees (electrical angle) from each other. It is configured to be Y-connected to the neutral point by a phase difference,
Of the three armature windings, two (a, b) have tap portions (H3, H4) at predetermined positions where the number of turns from the neutral point side winding start end is equal. And
A part of the two armature windings (a, b) between the tap portion (H3, H4) and the neutral point is (h3, h4);
The armature extension windings (d3, d4) having the same number of turns as a part (h3, h4) of the two armature windings are electrically connected to the armature winding b. (D4) is connected to the tap portion H4 so that the phase is electrically opposite to the armature winding a;
Thereby, each of the armature extension windings (d3, d4) is part (h3, h4) of the two armature windings (a, b) via the tap portions (H3, H4). Wherein the single-phase three-wire power supply is configured as a result of being connected together with the neutral point. Each predetermined position of the tap portions (H3, H4) is a position that bisects the number of turns of the two armature windings (a, b),
Thereby, each of the armature extension windings (d3, d4) is connected to the two armature windings (a, b) via the tap portions (H3, H4) together with the neutral point. 4. The alternator according to claim 3, wherein the single-phase three-wire power supply is configured as a result.

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