JPS61167348A - Controller for charging generator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a device for controlling the output voltage of a charging generator,
In particular, the present invention relates to a charging generator control device that can variably set the output voltage depending on the state of charge of a battery, etc.

[Background of the invention]

Since the output voltage of a charging generator of a car varies depending on the engine speed, it is controlled by an output voltage control device to be +1, which is suitable for the charging voltage. FIG. 3 shows a conventional charging generator control device. In the figure, the output voltage of armature coil/I/1 of the three-phase alternating current generator is rectified by a full-wave rectifier 2 to supply charging current to a battery 3.

The field coil 4 has a key switch 12 and a charging indicator light 13.
(at the time of start) or a field current is supplied from the auxiliary rectifier 14, but this current is turned on by the charging generator control device 5 (hereinafter simply referred to as the control device) to control the output voltage of the generator.

That is, at the start, the output voltage of the auxiliary rectifier 14 is sufficiently lower than the battery voltage, so the voltage e at the voltage dividing point of the resistor 9°lO is also low, and both the transistor 8 and the Zener diode 11 are off.

Therefore, the transistor 6 has a high base potential and is turned on because not much current flows through the resistor 7 at its base, so that current flows through the field coil 4. Therefore, the voltage of the generator gradually increases, and the voltage e turns on the Zener diode 11 and the transistor 8. When this happens, transistor 8 turns on and its collector potential goes down.
Transistor 6 is turned off, the field current is turned off, and the generator voltage drops. Then, e decreases again and the field current μ turns on, and eventually the power generation wall voltage is controlled to a setting determined by the voltage dividing ratio by the resistors 9 and 10 and the Zener voltage of the Zener diode 11. However, if the set voltage is always constant in this way, it is not possible to finely adjust the output voltage of the charging generator according to the light condition of the battery 3, thereby achieving economical fuel consumption. In order to deal with such drawbacks, a device is known in which an external power signal is applied depending on the state of charge of the battery to switch the set voltage in two stages. However, for fine-grained control, it is desirable to be able to vary the set voltage continuously rather than two-step switching, and a proposal for this is disclosed in Japanese Patent Laid-Open No. 154334/1983. In this method, a reference voltage that continuously changes depending on the state of charge of the battery is generated, and this reference voltage and the output voltage of the charging generator are compared using a comparator.In fact, both are appropriately divided and compared. ), the field current is turned on and off depending on its magnitude. However, variably setting the reference voltage in this way complicates the circuit configuration, which is undesirable from the viewpoint of reliability.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a charging generator control device with a simple configuration that can continuously vary the set value of the output voltage of the charging generator within a certain range depending on the charging state of the pantry.

[Summary of the invention]

The present invention is characterized in that the set voltage of the charging generator can be variably set isometrically by changing the current flowing through the voltage dividing resistor that divides the output voltage of the charging generator according to the charging state of the battery. That is.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. The circuit in the figure is almost the same as that explained in Figure 3, and
Items with the same reference numerals as those in the drawings have the same parts or functions. The difference is that in the control device 5A of the present invention, an emitter follower circuit consisting of a transistor 101 and a resistor 102 is connected between voltage dividing resistors 9 and 10. A Zener diode 103 and a base resistor 104 are connected to the base of the transistor 101, and a controller 105H calculates input data from various sensors to generate an output voltage Vct necessary to change the set voltage of the charging generator. In such a configuration, its basic operation is exactly the same as that shown in FIG. lO
The voltage e at the voltage dividing point is the sum of the Zener voltage V zll of the Zener diode 11 and the emitter voltage Vm of the transistor 8 eo = Vz 11 +V! l z a
...When the voltage exceeds (1), the transistor 6 is turned off; otherwise, the transistor 6 is turned on. Ru. Therefore, the apex C=eQ What kind of generator output 'Paper pressure vL
(the output point of the auxiliary rectifier 14) becomes the set voltage. That is, V t, = e 6 + Vg
-”(2).Here, v9 is the voltage drop across resistor 9, which is as follows.First, Zener diode 1
1: The current that flows is approximately the current Vmza that flows through the resistor 16.
/le1. (1. is the resistance value of resistor 15). The resistance value is the current flowing through the resistor 10. Then e67
几 is 0. The current flowing through the transistor 1OIK is approximately equal to the emitter current since this transistor works as an emitter follower, and this is <Vc V
mxt. I)/几, B (kl+IH1'!Resistance 102
The resistance value, Vmzlol, is the base-emitter voltage of the transistor 101. All of these t currents have a resistance of 9tla, so if the resistance value is 7t, then Vo ''(Vsv4/i(, In +eo/RIIO+
(VCV+z+ot)/ )(,at)・mu
...(3). Formula (2),
As is clear from (3), everything except the magnetic pressure Vc from the controller 105 can be regarded as a constant, so the set voltage V
L changes linearly according to changes in VC. However, if the Zener voltage tVz+os of the Zener diode 103 is V c > V z 1o3, the transistor 101
Since the pace potential of is clamped to V z 1°3, v
o, therefore VL is also clamped corresponding to this value, resulting in a characteristic as shown in FIG. That is, controller 1
The set voltage of the charging generator can be continuously varied within the range of 't6 by the output voltage of 05, and the circuit configuration can be made extremely simple.

〔Effect of the invention〕

As described above, according to the present invention, with a simple circuit configuration, it is possible to reduce the driving torque of the 9-meter generator whose set voltage can be varied within a certain range, and it is possible to improve the fuel efficiency of the engine.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing control characteristics of the embodiment of FIG. 1, and FIG. 3 is a diagram showing an example of a conventional charging generator control device. 1... Armature coil, 2... Full wave rectifier, 3...
Battery, 4... Field coil, 5... Charging generator control device, 6.8, 101... Transistor, 9.1
0...Voltage dividing resistor, 11,103... Zener diode, 105... Controller.

Claims (1)

[Claims] 1. The output voltage of the charging generator is divided by a voltage dividing resistor,
In a charging generator control device configured to adjust the output voltage by turning on and off the excitation current of the charging generator depending on whether the voltage at the voltage dividing point exceeds a predetermined reference value, Charging characterized in that the voltage division ratio of the voltage divider resistor is made variable by providing a bypass circuit that allows current to flow through one of the voltage divider resistors and whose current value can be adjusted by an external signal. Generator control device. 2. The charging generator control device according to claim 1, wherein the bypass circuit is configured such that its current value is variable only within a predetermined range of the external signal.