JPS6232693B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a single-phase synchronous generator that employs concentrated winding for both the armature winding and the field winding.

Prior Art In conventional generators, as shown in Figure 1, due to the shape of the armature 1, if the armature winding is concentrated winding, the utilization rate of the armature core will be poor and the voltage waveform will be inferior. Distributed winding is adopted in which the armature windings 2 are arranged evenly on the surface. However, armature windings that employ such distributed winding require unnecessary conductor wires that do not contribute to the generation of electromotive force between the slots at the bottom of different poles, and the overall length of the windings becomes long, resulting in large resistance. There is a problem in that the armature winding generates a lot of heat under load, resulting in energy loss and poor power generation efficiency.

In addition, in such conventional generators, the size is determined by the current density and number of windings of the armature winding, the slot cross-sectional area considering the space factor or workability during winding, and the pole cross-section due to the magnetic flux density. In addition, the slot opening in the armature is narrow, making it difficult to wind the armature winding and process its terminals, reducing work efficiency. It has become a bad thing.

In particular, for general-purpose generators where the connected load is not specified, such as engine generators used as portable commercial frequency power sources, the output waveform should be more sinusoidal to the extent that it does not adversely affect the load. It is also required that the output characteristics do not change significantly depending on the size of the load.

Purpose The present invention employs concentrated winding for the armature winding, which has a good utilization rate of the conductor and is advantageous for manufacturing, and also makes the use of the armature core easier by making the armature core and field core into a special shape. In addition to increasing the rate and approximating the output waveform to a sine wave, we also eliminate saturation of the magnetic flux that occurs during load, suppress the field current as much as possible, and reduce heat generation in the field winding, thereby increasing power generation. The present invention provides a single-phase synchronous generator that can further improve efficiency.

Configuration An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

Figure 2 shows the basic structure of a single-phase synchronous generator (horizontal shaft type) to which the present invention is applied. The armature core 4 has a storage chamber for the field core 5 formed adjacent to the armature winding 3 by protruding the four claws a, b, c, and d in the circumferential direction. A field winding 6 is wound with concentrated winding, and each end e, consisting of the field iron core 5 in which f, g, and h are respectively protruded in the circumferential direction;
As the field core 5 rotates, the magnetic resistance to the magnetomotive force of the field winding 6 is appropriately changed by the interaction between the magnetic pole and each of the claws a to d, thereby changing the distribution state of magnetic flux in the armature core 4. It is configured so that an alternating current voltage approximating a sine wave is induced in the armature winding 3 while changing over almost the entire circumference. Also,
In particular, for the claws a and b of the armature core 4, the cross-sectional area of each claw is directed toward the tip, so that the magnetic resistance increases toward the tip, and for the purpose of effectively reducing weight. Once formed to gradually decrease.

Regarding the operation of the single-phase synchronous generator with the basic structure to which the present invention is applied, configured as described above,
This will be explained below with reference to FIGS. 2 to 4.

First, as shown in FIG. 2, when the magnetic pole center O of the field core 5 is in a vertical position, the magnetic flux φ passes through the small magnetic resistance part of the armature core 4, and almost all of it passes through the armature winding 3. concentrates on the wrapped core part A. Therefore, when the magnetic pole center O of the field core 5 passes through that position, the rate of change in the magnetic flux becomes extremely small, and the voltage induced in the armature winding 3 at this time becomes zero. Next, the field core 5 rotates in the direction of the arrow R in the figure, and as shown in FIG. When it comes to face the tip of b through a gap, the magnetic flux φ
As shown in the figure, a portion of the magnetic flux also passes through the claw portion b of the armature core 4 through the gap, thereby reducing the number of magnetic fluxes passing through the portion A of the armature core 4. At this time, since the claw portions a and b of the armature core 4 are formed so that the cross-sectional area thereof gradually decreases toward the tip side, the decreasing gradient of the magnetic flux becomes gentle. Furthermore, when the rotation of the field core 5 progresses to a position as shown in FIG. , c and between b and d, respectively. At this time, there is no magnetic flux passing through the A part of the armature core 4, and when the magnetic pole center O of the field core 5 passes through the horizontal position, the direction of the magnetic flux passing through the A part of the armature core 4 is reversed. When the rate of change of magnetic flux becomes maximum, the voltage induced in the armature winding 3 becomes maximum. Therefore,
Due to the above 1/4 rotation of the field core 5, a 1/4 cycle AC voltage is induced in the armature winding 3 from zero until it gradually increases to the maximum value. . Similarly, 1/4 of the next field core 5
The AC voltage changes from the maximum value to zero by one rotation, and the AC voltage from zero to the maximum value of the opposite polarity by the next quarter rotation, and then by the next quarter rotation. As a result, alternating current voltages of opposite polarity from the maximum value to zero are sequentially induced in the armature winding 3.

In this way, in the single-phase synchronous generator with the basic structure to which the present invention is applied, even if concentrated winding is used as the armature winding 3, the armature core 4
The utilization rate is high, and the output waveform closely approximates a sine wave. Furthermore, heat generation in the armature winding 3 under load can be suppressed to reduce energy loss and improve power generation efficiency, and it is also possible to reduce size and weight and improve workability during manufacturing.

In the above-described single-phase synchronous generator, the present invention takes into account the influence of armature reaction especially under load, and reduces the magnetic flux saturation caused by making the armature core 4 into a special shape as described above. I'm trying to solve the problem.

That is, for the claw portion a of the armature core 4,
In the state shown in Fig. 2, the maximum magnetic flux passes through part A of the armature core 4 around which the armature winding 3 is wound, and then the number of magnetic fluxes gradually decreases as the field core 5 rotates. It is formed so that the cross-sectional area gradually changes in order to increase the magnetic resistance toward the tip, and in order to prevent the magnetic flux from becoming saturated, the left side of the field core 5 is It is determined to have the minimum cross-sectional area necessary for half of the magnetic flux to pass through.

However, in this way, the claw portion a of the armature core 4
If we determine the cross-sectional area of Since the point at which the load is applied is slightly delayed compared to when there is no load (see Fig. 2), the resistance load RL is now connected to the armature winding 3 as shown in Fig. 7 a and b (see Fig. 6). Under the condition that the output voltage and the load current flowing through the armature winding 3 are in phase, the field magnetic flux is influenced by the magnetic flux φ _A generated by the load current, and the magnetic flux distribution changes. effect). That is, since the mechanical zero point and the electrical zero point in the generator do not necessarily coincide, as shown in FIG. The point where _L is maximum is delayed by the electrical angle α from the point where the passing magnetic flux φo is maximum under no load, and the output voltage V under load is
The maximum point of _L lags behind the maximum point of the output voltage Vo of the no-load magnet by the phase α. Note that FIG. 7a shows the state at point A in FIG. 8, and FIG. 7b shows the state at point C in FIG. At points A and C, φ _A increases the amount of orientation of φ _L , respectively.
In FIG. 8, arrows indicate the direction of rotation of the field core 5.

Therefore, the amount of magnetic flux passing through the portion of the armature core 4 above the magnetic pole center O of the field core 5 becomes larger than that when no load is applied, and the magnetic flux density in that portion becomes high. At this time, the iron plate (electrical iron plate) used in the armature core 4 usually has magnetic flux saturation characteristics as shown in Figure 5, and when the magnetic flux density B exceeds a certain value, the magnetomotive force AT suddenly increases. rise to That is, if a large amount of magnetomotive force AT is required, an additional field current is required and the field winding 6 generates heat, resulting in a decrease in generator efficiency.

Therefore, in the single-phase synchronous generator according to the present invention, as shown in FIG. 6, when the point at which the magnetic flux φ in the armature winding 3 becomes maximum during load is delayed (the phase delay angle α of the maximum magnetic flux) However, in order to prevent the magnetic flux from being saturated at the claw part a of the armature core 4, the magnetic pole cross section X2 of the armature core 4 is shown in FIG.
By increasing the field current, the field current is reduced, heat generation in the field winding 6 is suppressed, and power generation efficiency is improved.

Effects As described above, in the single-phase synchronous generator according to the present invention, the armature winding is wound in concentrated winding on one side, and four pawl portions whose cross-sectional area gradually decreases toward the tip are arranged on each side. an armature core in which a storage chamber for the field core is formed by protruding in the circumferential direction so as to form a gap between the claw portions, and a field winding wound in concentrated winding; Each end of a magnetic pole having a two-pole structure is composed of the field core protruding in the circumferential direction, and for the magnetic pole of the armature core,
The magnetic flux density increases because the point at which the magnetic flux passing through the armature winding reaches its maximum during load is delayed compared to when no load is applied.The cross-sectional area of the magnetic pole on one side is made larger than the cross-sectional area of the magnetic pole on the opposite side. With this, it is possible to obtain an output voltage with good sinusoidal characteristics, and it has the excellent advantage of suppressing heat generation in the field winding and improving power generation efficiency. There is.

[Brief explanation of the drawing]

Figure 1 is a simplified configuration diagram of a generator with a conventional distributed winding armature winding structure, and Figure 2 is a simplified configuration diagram showing the basic structure of a single-phase synchronous generator to which the present invention is applied. , Fig. 3 and Fig. 4 are diagrams showing the operating states of the generator, Fig. 5 is a diagram showing the magnetic flux saturation characteristics of a general armature core, and Fig. 6 is a diagram showing a single-phase synchronous system to which the present invention is applied. A simplified configuration diagram showing an example of a generator. Figures 7a and 7b are diagrams showing the state of magnetic flux generated by the load current flowing through the armature winding, respectively. Figure 8 is a diagram showing the armature under no load and under load. FIG. 2 is a waveform diagram showing characteristics of magnetic flux passing through a winding and output voltage. 3... Armature winding, 4... Armature core, 5...
Field iron core, 6...Field winding, a to d...Claw portion, X
1,X2...Pole cross section.

Claims (1)

[Claims] 1. The armature winding is wound in concentrated winding on one side, and four pawls whose cross-sectional area gradually decreases toward the tip are arranged in the circumferential direction so that a gap is formed between each opposing pawl. The armature core has a field core storage chamber formed by protruding from it, and the field winding is wound with concentrated winding, with each end of the magnetic pole having a two-pole structure protruding in the circumferential direction. The magnetic pole of the armature core is
The magnetic flux density increases because the point at which the magnetic flux passing through the armature winding reaches its maximum during load is delayed compared to when no load is applied.The cross-sectional area of the magnetic pole on one side is made larger than the cross-sectional area of the magnetic pole on the opposite side. A single-phase synchronous generator.