JP2598700Y2 - Excitation structure of automotive generator - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an exciting structure of a generator for an automobile, in particular, having a plurality of exciting windings, changing an exciting mode by the plurality of exciting windings according to a load state, and changing an output voltage to a constant voltage. The present invention relates to an excitation structure of a generator for an automobile.

[0002]

2. Description of the Related Art A conventional motor generator for an automobile, that is, an alternator and a regulator thereof, have a configuration shown in FIG.

In FIG. 1, reference numeral 1 denotes an alternator provided with a rectifier.
Is converted to a direct current to output a direct current voltage. The exciting winding 4 is for the power generating winding 2, and the exciting current flowing through the exciting winding 4 is controlled by the regulator 5 so that the output voltage of the alternator 1 is made constant.

That is, when the output voltage of the alternator 1 rises, the constant voltage diode 9 is turned on, so that the transistor 10 is turned on and the Darlington-connected transistor 8 is turned off, so that the exciting current flowing through the exciting winding 4 is reduced. It is shut off and the output voltage of the alternator 1 drops.

On the other hand, when the output voltage of the alternator 1 decreases, the constant voltage diode 9 is turned off, the transistor 10 is turned off, and the Darling connection transistor 8 is turned on, so that the exciting current continues to flow through the exciting winding 4. , The output voltage of the alternator 1 is controlled to be increased.

[0006] The DC voltage generated in the alternator 1 charges the battery 6 through the switch 7 and supplies the power to electric components (not shown). FIG. 8 is a partial explanatory view of a winding structure of a conventional exciting winding.

The exciting winding 4 shown in FIG. 7 has a coil having a diameter φ wound around the bobbin 11 T times as shown in FIG. The winding radius is Φ
Then, the total resistance R can be expressed by Expression 1 where the resistivity of the coil is ρ.

[0008]

(Equation 1)

Therefore, when the exciting current flowing through the exciting winding 4 is I, the magnetomotive force AT is expressed by the following equation (2).

[0010]

(Equation 2)

Here, V is the output voltage of the alternator 1. FIG. 9 is a graph showing output current characteristics with respect to the number of rotations of the alternator, and shows one excitation winding 4 shown in FIG.
In this case, the output characteristics were limited to those shown in FIG.

[0012]

In an excitation structure in which excitation is performed by one excitation winding 4 as in the prior art, the output characteristics thereof are determined as shown in FIG. For example, when the load is light, the battery 6 tends to be overcharged, and when the load is heavy, the output of the alternator 1 is insufficient.

As a solution to this, as shown in FIGS. 10 and 11, two alternators, a main alternator 12 and a sub-alternator 13, are prepared, and the main alternator 1 normally controlled by a regulator 14 is provided.
2, the sub-alternator 13 is generated by the control of the regulator 15 which operates by detecting the drop of the output voltage when the load is heavy, and obtains the characteristic shown in FIG. Was.

FIG. 1B shows a main alternator 1.
2 shows the output characteristics of one of the devices. However,
In a configuration in which the sub-alternator 13 is operated in parallel with the main alternator 12 in a state of supporting a heavy load, FIG.
As shown in (1), two alternators are required to be mounted around the engine 16, which increases the weight and complicates the drive system.

In addition, since the sub-alternator 13 does not generate power at a light load, there is a problem that the sub-alternator 13 is not sufficiently used.
The present invention has been made in view of the above points, and has a structure in which a plurality of excitation windings are provided for one power generation winding of an alternator, and the plurality of excitation windings are formed in accordance with a load.
It is an object of the present invention to provide an excitation structure for an automotive generator in which an excitation state is automatically changed and one alternator solves the above problem.

[0016]

Means for Solving the Problems To achieve the above object,
The excitation structure of the automotive generator of the present invention
It has a rectifier to convert the DC voltage into a constant voltage.
One generator winding and chain
Generate intersecting magnetic fluxWith two excitation windings,this2Pieces
By controlling the excitation current individually for each excitation windingOut
Voltage E with different force ₁ , E _Two (E ₁ > E _Two ) For constant voltage
The first and second excitation current control units that perform
Voltage E ₁ At constant voltage, and at heavy load
The above-mentioned voltage E _Two With constant voltage
Configured toIt is characterized by.And update
To generate two magnetic fluxes linked to one power generation winding
Excitation windings and each of these two excitation windings
To control the excitation current of ₁ , E
_Two (E ₁ > E _Two ), The first and second exciting currents to be constant voltage
The control unit and two excitation windings are connected in series at light load.
Output to the voltage E ₁ To make constant voltage, 2 pieces under heavy load
And the output is connected to the voltage E _Two At constant
And an automatic switching circuit for
I have.

[0017]

FIG. 1 shows an embodiment of the present invention.
Reference numerals 1 to 3, 5 to 7 correspond to those in FIG.

The alternator 1 of the present invention has two excitation windings 31 and 41. These two excitation windings 31,
As shown in FIG. 2, 41 has a structure in which it is individually wound around a bobbin 11 attached to a rotor.

The regulator 5 has two exciting current control units 32 and 42 and a voltage detection unit composed of resistors 18, 19 and 20. Exciting current control unit 32
Controls the exciting current flowing in the exciting winding 31. In a normal case with a light load, the exciting current controller 3 controls the exciting current.
By the control of 2, the output voltage of the alternator 1 is made constant. The other exciting current control unit 42 controls the exciting current flowing through the exciting winding 41, and when the output voltage of the alternator 1 drops below a predetermined constant voltage during heavy load or the like, the exciting current control unit 42 Operates to increase the output of the alternator 1.

For example, when the output of the alternator 1 is a 24 V system, the constant voltage diode 33 in the exciting current control unit 32 is turned on when the output voltage is 28.5 V, and the exciting current control unit 4
The constant voltage diode 43 in 2 is selected so that its output voltage turns on at 28V.

Therefore, the output voltage of the alternator 1 becomes 2
When the constant voltage is set to 8.5 V, the exciting current control unit 4
2, the constant voltage diode 43 is always on, the transistor 44 is on, the Darlington-connected transistor 45 is off, no exciting current flows through the exciting winding 41, and the alternator 1 The output voltage is made constant by controlling the exciting current flowing from the exciting current control unit 32 to the exciting winding 31. That is, the transistor 34 is controlled to be on and off in accordance with the on and off of the constant voltage diode 33, and the Darlington-connected transistor 35 is controlled to be off and on, respectively, so that the output voltage is 28.5V.
The exciting current flows into the exciting winding 31 such that

On the other hand, when the load becomes heavy and the output voltage of the alternator 1 drops to 28 V or less, the exciting current control unit 4
The constant voltage diode 43 in 2 is turned off. As a result, the transistor 44 is turned off and the Darlington-connected transistor 45 is turned on, so that the exciting current flows into the exciting winding 41. At this time, the constant voltage diode 33 in the exciting current controller 32 is turned off because the output voltage is 28 V or less, and the exciting current flows into the exciting winding 31. Therefore, the magnets are excited by the two exciting windings 31 and 41, the magnetomotive force is increased, and the output of the alternator 1 is increased, resulting in the output characteristic shown in FIG. FIG. 3B shows the output characteristics of one excitation winding 31.

Although the output can be enhanced in this way,
The output voltage of the alternator 1 is turned into a constant voltage by turning on and off the constant voltage diode 43, that is, under the control of the exciting current control unit 42, and is turned into a constant voltage of 28V.

When the load becomes lighter and the output voltage of the alternator 1 recovers to 28 V or more, the constant voltage diode 43 is always on, so that the exciting current to the exciting winding 41 is cut off. Shift to constant voltage control to 5V.

FIG. 4 shows another embodiment of the present invention. FIG. 2 shows a configuration in which an automatic switching circuit 21 is added to the configuration shown in FIG.
Connection switching is performed so that 1 and 41 are connected in series or in parallel by the operation of the automatic switching circuit 21.

The automatic switching circuit 21 includes transistors 22 and 2
3, constant voltage diode 24, diode 25 and resistor 2
The constant voltage diode 24 is turned on at the same voltage as the constant voltage diode 33 in the exciting current control unit 32, and a voltage slightly lower than the constant voltage diode 43 in the exciting current control unit 42. Is selected to be on. For example, when the output of the alternator 1 is a 24V system as in the case of FIG. 1, when the output voltage of the alternator 1 is 28V, the constant voltage diodes 24 and 33 are turned on, and the constant voltage diode 43 is connected to the alternator 1
Is turned on when the output voltage is 28.5V.

When the load is light and the output voltage of the alternator 1 is 2
When the constant voltage is set to 8.5 V, the automatic switching circuit 21
The constant voltage diode 24 in the internal circuit and the constant voltage diode 33 in the exciting current control unit 32 are always in the ON state, and the transistor 23 in the automatic switching circuit 21 and the Darlington-connected transistor 35 in the exciting current control unit 32 Are both turned off.

At this time, the exciting windings 31 and 41 are connected in series via the diode 25 in the automatic switching circuit 21, and the output voltage of the alternator 1 is controlled by the exciting current controlled by the exciting current control unit 42. By flowing through the connected excitation windings 31 and 41, the voltage is made constant at 28.5V.

On the other hand, when the load becomes heavy and the output voltage of the alternator 1 drops below 28 V, the automatic switching circuit 21
, And the constant voltage diode 33 in the exciting current control unit 32 is turned off.

The constant voltage diode 2 in the automatic switching circuit 21
When the transistor 4 is turned off, the transistor 23 is turned on, and when the transistor 23 is turned on, the exciting windings 31 and 41 are connected in parallel. Since the constant voltage diode 33 in the excitation current control unit 32 is off, the Darlington-connected transistor 35 is always on, and the excitation current always flows through the excitation winding 31.
Further, since the constant voltage diode 43 in the exciting current control unit 42 is also off, the Darlington-connected transistor 4
5 is turned on, the exciting current also flows through the exciting winding 41, and the magnetomotive force is increased by the parallel connection of the exciting windings 31 and 41 (the reason why the magnetomotive force is increased will be described later). The output characteristic is enhanced, and the output characteristic shown in FIG. In the figure, (D) shows the output characteristics when the exciting windings 31 and 41 are connected in series.

Although the output can be increased in this way,
The output voltage of the alternator 1 is made constant by turning on and off the constant voltage diode 33, that is, by the control of the exciting current control unit 32, and is made constant at 28V.

When the load is reduced and the output voltage of the alternator 1 recovers to 28 V or more, the constant voltage diode 24 in the automatic switching circuit 21 is turned on and the transistor 23 is turned off, so that the excitation windings 31 and 41 are turned off. The parallel connection mode is restored to the serial connection, and the operation shifts to the constant voltage control of 28.5 V by the exciting current control unit 42 .

Here, the difference in magnetomotive force between the series connection and the parallel connection of the excitation windings 31 and 41 will be described. The combined resistance R ₁ when the exciting windings 31 and 41 shown in FIG. 2 are connected in series is expressed by Equation 1, and the combined resistance R ₂ when the exciting windings 31 and 41 are connected in parallel is , Excitation winding 31,
Since the number of windings of the coil 41 is １ ／, it is １ ／ of the combined resistance R ₁ of the series connection.

[0034] Therefore, the magnetomotive force AT ₂ when the magnetomotive force AT ₁ and parallel connections when the excitation winding 31 and 41 connected in series is represented by the number 3.

[0035]

(Equation 3)

By switching the series connection of the exciting windings 31 and 41 to the parallel connection, the magnetomotive force is doubled, and the output characteristic shown in FIG. 5C is obtained.

In the case of the present invention, since the power is increased by one alternator 1, as shown in FIG. 6, the space for mounting on the engine 16 is small, and the weight is one of the alternators. And the drive system is simplified.

[0038]

[Effects of the Invention] As described above, according to the present invention, 1
A plurality of excitation windings are prepared for each power generation winding, and the use of the excitation windings is automatically switched according to the load condition to be used, or automatically switched from series connection to parallel connection according to the load condition. With this configuration, it is possible to cope with light and heavy loads, and since only one alternator can be used, the space can be reduced and the drive system can be simplified.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention.

FIG. 2 is a diagram illustrating the winding of an exciting winding according to the present invention.

FIG. 3 is an output characteristic diagram illustrating output characteristics of the configuration shown in FIG. 1 of the present invention;

FIG. 4 shows another embodiment of the present invention.

5 is an output characteristic diagram illustrating the output characteristics of the configuration shown in FIG. 4 of the present invention.

FIG. 6 is an explanatory view of the alternator mounting of the present invention.

FIG. 7 is a configuration diagram of a conventional automobile generator.

FIG. 8 is a diagram for explaining winding of an exciting winding.

FIG. 9 is a conventional output characteristic diagram.

FIG. 10 is a configuration diagram of a conventional automotive generator for coping with a heavy load.

FIG. 11 is an explanatory view of mounting a conventional alternator.

FIG. 12 is an output characteristic diagram illustrating output characteristics of a conventional configuration.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 alternator 2 generator winding 3 rectifier 4 excitation winding 5 regulator 6 battery 21 automatic switching circuit 31, 41 excitation winding 32, 42 excitation current controller

Claims (2)

(57) [Scope of request for utility model registration] 1. An automotive power generator comprising a rectifier for converting an alternating current to a direct current and outputting a constant-voltage DC voltage, wherein two excitations for generating a magnetic flux linked to one power generating winding.
Winding and the voltage E ₁ output is different the two exciting each winding in each control the exciting current individually, E ₂ (E _1> E ₂₎
First and second excitation current controller, a constant voltage by the voltage E ₁ at one excitation winding at light loads in a constant voltage
When the load is heavy, the two excitation windings are connected in parallel to
Excitation structure for an automobile generator, characterized by being configured to constant voltage at pressure E _2. And a rectifier for converting an alternating current into a direct current.
For automotive power generators that output voltage DC voltage
And two excitations that generate a magnetic flux linked to one power generation winding
And the exciting currents for each of these two exciting windings.
Voltages E ₁ , E _{2 controlled} (E ₁ > E ₂ ) with different outputs
The first and second excitation current control units, which are set to a constant voltage by the above, and two excitation windings are connected in series at light load to increase the output.
Serial and constant voltage at the voltage E _1, 2 pieces of excitation windings at heavy loads
To constant voltage above the voltage E ₂ output are connected in parallel to the own
Automotive onset, characterized by comprising a Dosetsu circuit
Excitation structure of electric machine.