JPH1141886A - Three-phase alternator for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a three-phase alternator, capable of materializing ripple reduction on a generated voltage and the improvement of the output current in the medium and high-speed range, while suppressing the deterioration of low-speed start-up property of the generated voltage. SOLUTION: An armature coil (Y-Δ parallel connection for armature coil) consists of a Y-connection armature coil and a Δ-connection armature coil which are wound in the same slot of an armature core and are connected in parallel with each other. Here, the number of turns of the Δ-connection armature coil is set to the integer value one or two turns less than the integral value coming closest to 1.73 times the number of turns of the Y-connection armature coils and furthermore is larger than the number of turns of the U-connection armature coil. By doing so, the output current property in middle and high-speed range can be improved, while suppressing the deterioration in the ripple factor and the low-speed start-up property of the voltage generated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a three-phase AC generator for a vehicle.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. 4-427 filed by the present applicant.
No. 59 discloses an armature coil (hereinafter referred to as a Y-Δ parallel connection type armature coil) composed of a Y-connection armature coil and a Δ-connection armature coil wound around the same slot of an armature core, A three-phase AC generator for vehicles that separately rectifies the voltage generated by both coils has been proposed.

[0003] Here, the number of turns of both armature coils is the ratio of the number of turns at which the maximum voltage between the two wires is equal, that is,
When the number of turns of the Y-connection armature coil is 1, the number of turns of the Δ-connection armature coil is an integer close to 1.73 (hereinafter, the ratio of the number of turns is the ideal number of turns). Ratio). Since the above-described armature coil of the Y-Δ parallel connection type operates to generate a pseudo six-phase AC voltage, the pulsation rate (ripple) of the generated voltage in a low rotation speed region such as when the vehicle is idling is large. It has excellent characteristics in phase alternator.

The line-to-line coil resistance of the two coils is set to be equal. This is due to the balance between the resistance loss and the generated voltage. On the other hand, a conventional three-phase AC generator for a vehicle has a configuration in which a large current (100 A or more) is output in principle because the generated voltage is small corresponding to the on-vehicle battery voltage. Due to the demand for output, the number of turns of the armature coil must be limited to about 10 turns or less even for a small current output type, and to only a few turns for a large current output type. Is gone.

More specifically, under such a large current output, the resistance loss of the armature coil and the resulting heat generation increase. For this reason, in the conventional three-phase AC generator for vehicles,
By reducing the number of turns of the armature coil, the armature coil having the largest possible cross-sectional area is accommodated in the slot of the armature core.

[0006]

However, such a reduction in the number of turns of the armature coil (and an increase in the cross-sectional area of the armature coil) causes an output current to be generated almost in inverse proportion thereto. This causes an increase in the minimum engine speed, that is, a deterioration in the low-speed rise characteristic of the generated voltage.

That is, the number of turns of the armature coil can be reduced by reducing the resistance loss of the armature coil, thereby improving the output current characteristics at a large power generation voltage (middle / high speed range) and the output current characteristics at a low speed range. Will be worse. In particular, as described above, the number of turns of the armature coil of the three-phase AC generator for a vehicle is as small as only a few turns. Therefore, only one or two turns are reduced, and the low-speed rising characteristic of the generated voltage is ignored. It leads to an impossible deterioration.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and it is an object of the present invention to reduce the pulsation rate of the generated voltage and to improve the output current characteristic in a medium to high speed range while suppressing the deterioration of the low-speed rising characteristic of the generated voltage. It is an object of the present invention to provide a feasible three-phase alternator for vehicles.

[0009]

According to the present invention, there is provided a three-phase AC generator for a vehicle, wherein the three-phase AC generator is wound around the same slot of an armature core and connected to each other in parallel. In an armature coil (Y-.DELTA. Parallel connection type armature coil) composed of a Y connection armature coil and a .DELTA. Connection armature coil, the number of turns of the .DELTA. Connection armature coil is equal to that of the Y connection armature coil. It is set to an integer value that is one or two turns less than the integer value closest to 1.73 times the number and greater than the number of turns of the Y-connection armature coil.

In this way, it is possible to improve the output current characteristics in the middle and high speed range while suppressing the deterioration of the pulsation rate and the low-speed rise characteristics of the generated voltage. Hereinafter, the realization of the above operation and effect will be described more specifically. First, since the armature coil adopts the configuration of the Y-Δ parallel connection type armature coil, as described above, the pulsation rate of the generated voltage can be reduced by using a normal Y-connection armature coil or a Δ-connection armature coil. It can be greatly improved compared to the case of using alone.

Further, since only the number of turns of the .DELTA.-connection armature coil is reduced by one to two turns as compared with the conventional art, the coil cross-sectional area of the armature coil can be increased by that amount. It is possible to improve the output current characteristics in the middle and high speed regions. Further, since the number of turns of the Y-connection armature coil is not reduced in this configuration, in other words, only the number of turns of the Δ-connection armature coil which constitutes a part of the armature coil, and one or two of the turns. Since only the number of turns is reduced, the rate of reduction in the number of turns of the armature coil as a whole is 0.5 to 1 turn less than when the entire armature coil is regarded as a Δ-connection armature coil. Almost the same, 0.3% more than when the entire armature coil is regarded as a Y-connection armature coil.
Approximately the same as reducing by about 0.5 turn.

As a result, the lowering of the low-speed rising characteristic of the generated voltage by the present configuration is slight, and the effect of increasing the output current by lowering the coil resistance due to the reduction in the number of turns is, of course, somewhat present even in the low-speed range. As a result, it is possible to improve the output current characteristics in the middle to high speed range while suppressing the lowering of the low-speed rising characteristics of the generated voltage. In addition, instead of reducing the number of turns of the Δ-connection armature coil,
It is also conceivable to reduce the number of turns of the Y-connection armature coil to improve the output current characteristics in a middle to high speed range. However, in this case, as described above, in the three-phase AC generator for a vehicle, the number of turns of the Y-Δ parallel-connected armature coil, which is extremely small, which is originally a few turns, is further reduced. Therefore, the deterioration of the low-speed rising characteristic of the generated voltage due to the above becomes too large to be ignored. Of course, it is sufficient if the number of turns corresponding to a fractional value less than 1 can be reduced by, for example, 1/2 turn, such as 0.5 turns of the Δ-connection armature coil. Reducing the number of turns is not easy or practical in terms of phase coil or connection work.

Based on the above analysis, the inventor of the present invention has proposed an armature coil (Y-shaped armature coil comprising a Y-connection armature coil and a Δ-connection armature coil wound in the same slot of an armature core and connected in parallel with each other. In the [Delta] parallel connection type armature coil, the number of turns of the [Delta] connection armature coil is from 1 to 2 from the smallest integer closest to 1.73 times the number of turns of the Y connection armature coil. Since the value obtained by subtracting the turn was used, it was possible to improve the output current characteristic in the middle to high speed range while suppressing the deterioration of the pulsation rate and the low-speed rising characteristic of the generated voltage.

According to a second aspect of the present invention, in the three-phase AC generator for a vehicle according to the first aspect, the Y-connection armature coil is further set to 3 to 5 turns. If you do this,
Since both armature coils have a small number of turns, they reduce internal resistance loss at high current as a three-phase AC generator for vehicles,
A large current can be output. Incidentally, the preferred combination of the number of turns in this embodiment is as follows. When the number of turns of the Y-connection armature coil is 5, the number of turns of the Δ-connection armature coil is 9 which is an integer value closest to 1.73 times, and 7 or 8 turns is preferable. When the Y-connection armature coil has four turns, the Δ-connection armature coil turns
As for the number of turns, the integer value closest to 1.73 times is 7, and 5 or 6 turns are preferable.

According to a third aspect of the present invention, in the three-phase AC generator for a vehicle according to the first or second aspect, further, the line-to-line coil resistance of the Δ-connection armature coil is the line-to-line coil resistance of the Y-connection armature coil. Is set to 0.8 to 1.2 times. By doing so, it is possible to reduce loss and variation in output current based on the resistance difference between the Y-connection armature coil and the Δ-connection armature coil.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a three-phase AC generator for a vehicle according to the present invention will be described below with reference to FIG. Reference numeral 1 denotes a vehicle alternator, which supplies power to a battery 2 and an electric load 3. 10
Denotes a Y-connected first armature coil (Y-connected armature coil), and respective phase coils 101 and 102 constituting the first armature coil.
And 103 have one ends x ′, y ′, z ′ connected to each other,
The other ends x, y and z are connected to the input terminals of the full-wave rectifier 11.

Reference numeral 12 denotes a △ -connected second armature coil (Δ-connection armature coil), and each end U and W 'of each phase coil 121, 122 and 123 constituting the same, and V and U'. , W and U ′ are connected to each other, and these three connection points are connected to the input terminal of the full-wave rectifier 13. Of the respective phase coils of both armature coils 10 and 12, phase coil 10
1 and 121, 102 and 122, and 103 and 123 are respectively inserted in the same slot of the armature core. Although the winding method of both armature coils 10 and 12 is the same as the wave winding, the winding may be wrapped.

In the Y-connection armature coil 10, the phase coil 101 starts at one end X and reaches the other end X 'via slots 164, 167,..., 161 as shown in FIG. The phase coil 102 starts from a slot delayed by 120 degrees in electrical angle with respect to the phase coil 101, and the phase coil 103 starts from a slot delayed by 240 degrees with respect to the phase coil 101, and is wound in the same manner as the phase coil 101. Is equipped. In the Δ-connection armature coil 12, the phase coils 121 to 123 are wound similarly to the phase coils 101 to 103 as shown in FIG.

According to the above configuration, the rectified voltage ripple of the full-wave rectifier 11 and the rectified voltage ripple of the full-wave rectifier 13 have a phase angle different from each other by 30 degrees. The pulsation rate is reduced as compared with the case where the armature coil is constituted by only one of the Δ-connection armature coils. The number of turns of the Y-connection armature coil 10 and Δ
The ratio of the number of turns of the connection armature coil 12 is 1: 1.73.
And Accordingly, the magnitude of the line voltage of the Δ-connection armature coil 12 and the magnitude of the line voltage of the Y-connection armature coil 10 match, and the pulsation rate can be reduced. Since this is well known, the description is omitted.

The three-phase AC voltages generated by the armature coils 10 and 12 are separately rectified by full-wave rectifiers 11 and 13 and supplied to the battery 2. 14 is a field coil,
Reference numeral 15 denotes a voltage regulator. The voltage regulator 15 energizes the field coil 14 when the voltage of the battery 2 is equal to or lower than a predetermined value to put the generator 1 into a power generation state. When the voltage of the battery 2 is equal to or higher than the predetermined value, The current flowing through the field coil 14 is cut off to stop the generator 1 from generating power, whereby the voltage of the battery 2 is adjusted to a predetermined voltage.

The features of this embodiment will be described below.
In this embodiment, the number of turns of the Δ-connection armature coil 12 is one or two turns smaller than the integer value closest to 1.73 times the number of turns of the Y-connection armature coil 10, and
The value was set to an integer value larger than the number of turns of the Y-connection armature coil 10. Further, in order to obtain a large output current, the Y-connection armature coil 10 is set to 4 or 5 turns.

By doing so, the output current characteristic in the middle and high speed range is improved while suppressing the deterioration of the pulsation rate of the generated voltage and the low-speed rising characteristic of the generated voltage for the reason described above. be able to. The re-discussion of the above reasons will be omitted. (Test 1) Next, a prototype of a three-phase AC generator for a vehicle in the form of a Y-Δ parallel connection type armature coil in which the number of turns of the Y-connection armature coil 10 was 5 was actually produced. The relationship between the rotational speed and the maximum output current was examined by variously changing the turn ratio of the secondary coil 12.

However, the generated voltage of the vehicle three-phase AC generator 1 used was 13.5 V, and the ambient temperature was 25 ° C.
The coil cross-sectional area was set so that the coil resistance of the Y-connection armature coil 10 and the coil resistance of the Δ-connection armature coil 12 were equal. The number of turns of the Δ-connection armature coil 12 was selected as follows. In the first embodiment, the turn is 8 turns.
The product of Example 2 had 7 turns, the product of Comparative Example 1 (ideal ratio product, conventional product) had 9 turns, and the product of Comparative Example 2 (conversely, the number of turns of the Δ-connection armature coil 12 was increased. If you do)
In the third comparative example (when the number of turns of the Y-connection armature coil 10 is smaller than the ideal turn number ratio), the number of turns of the Y-connection armature coil 10 is 4, and the connection is Δ. The number of turns of the armature coil 12 was set to nine.

FIG. 4 shows the result. From FIG. 4, it can be seen that the products of Examples 1 and 2 can improve the output current characteristics in the middle and high speed range while suppressing the deterioration of the low-speed rising characteristics of the generated voltage, as compared with the products of Comparative Examples 1, 2, and 3. Proven. (Test 2) Further, a three-phase AC generator for a vehicle in the form of a Y-Δ parallel connection type armature coil in which the number of turns of the Y-connection armature coil 10 was 4 was actually prototyped, and the Δ-connection armature was used. The relationship between the rotation speed and the maximum output current was examined by variously changing the turn ratio of the coil 12.

However, the parameters of the vehicle three-phase AC generator 1 used were the same as in Test 1. 6 for Example 3
In the fourth example, the turn was 5 turns. In the fourth comparative example (ideal ratio product, conventional product), the turn was 7 turns. In the fifth comparative example (reversely, the turn of the Δ-connection armature coil 12 was performed). In the case of the product of Comparative Example 6 (when the number of turns of the Y-connection armature coil 10 is smaller than the ideal turn number ratio), the turn of the Y-connection armature coil 10 is used. The number of turns was 3, and the number of turns of the Δ-connection armature coil 12 was 7.

FIG. 5 shows the results. From FIG. 5, it can be seen that the products of Examples 3 and 4 can improve the output current characteristics in the middle and high speed range while suppressing the deterioration of the low-speed rising characteristic of the generated voltage as compared with the products of Comparative Examples 4, 5, and 6. Proven.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing one embodiment of an automotive alternator according to the present invention.

FIG. 2 is a schematic winding diagram of a Y-connection armature coil 10;

FIG. 3 is a schematic winding diagram of a Δ-connection armature coil 12;

FIG. 4 shows a case where the Y-connection armature coil 10 has 5 turns and Δ
FIG. 9 is a characteristic diagram showing a relationship between the rotation speed and the maximum output current when the number of turns of the connection armature coil 12 is variously changed.

FIG. 5 shows a case where the Y-connection armature coil 10 has four turns, and Δ
FIG. 9 is a characteristic diagram showing a relationship between the rotation speed and the maximum output current when the number of turns of the connection armature coil 12 is variously changed.

[Explanation of symbols]

1 is a three-phase AC generator for vehicles, 10 is a Y-connection armature coil, 12 is a Δ-connection armature coil, and 11 and 13 are full-wave rectifiers (rectifying means).

Claims (3)

[Claims] 1. An armature coil comprising a Y-connection armature coil and a .DELTA.-connection armature coil wound in the same slot of an armature core, and a three-phase AC voltage generated by the two coils is full-wave independent of each other. In a three-phase AC generator for a vehicle, comprising a rectifier for rectifying and supplying power to a battery, the number of turns of the Δ-connection armature coil is 1.73 times the number of turns of the Y-connection armature coil. A three-phase AC generator for a vehicle, wherein the integer value is set to an integer value smaller by one or two than an integer value closest to the above, and larger than the number of turns of the Y-connection armature coil. 2. The three-phase AC generator for a vehicle according to claim 1, wherein the Y-connection armature coil is set to 3 to 5 turns. . 3. The three-phase AC generator for a vehicle according to claim 1, wherein a line coil resistance of the Δ-connection armature coil is 0.8 to less than a line coil resistance of the Y-connection armature coil. A three-phase AC generator for vehicles, which is set to 1.2 times.