JPS5915231Y2 - Charging generator control device - Google Patents

Description

[Detailed description of the invention] This invention relates to a charging generator control device that controls the output voltage of the generator to a predetermined value to charge a storage battery, and particularly uses an AC generator as the charging generator. The present invention relates to a charging generator control device in which the entire circuit can be easily integrated into an IC without requiring any special elements.

First, a conventional device of this type will be explained with reference to FIGS. 1 and 2.

In FIG. 1, reference numeral 1 denotes an alternating current generator installed in a vehicle (not shown) and driven by an internal combustion engine (not shown), which has an armature coil 101 and a field coil 102 connected in a three-phase star shape.

2 is a full-wave rectifier for rectifying the alternating current output of the generator 1, 201 is a (+) rectifier output end, and 202 is a (-) rectifier output end.

Reference numeral 3 denotes a semiconductor voltage regulator that controls the output voltage of the generator 1 to a predetermined value, and is composed of the following parts.

That is, 301 is a surge absorbing diode connected to both ends of the field coil 102, and 302 and 303 are output transistors connected to each other in a Darlington connection, which are switching elements for cutting and shutting the field current of the field coil 102.

304 is a resistor provided in the base circuit of the output transistors 302 and 303, and 305 is the output transistor 3.
02. Control transistor for intermittent control of 303, 306
307. is a Zener diode that detects the output voltage of the generator 1 and becomes conductive when the output voltage reaches a predetermined value.
308.309 is a temperature compensation diode connected in series in the forward direction to the Zener diode 306; 310.311
is the (+) output end 20L of the generator 1 (-) output end 2
02 are connected in series to form a voltage dividing circuit for detecting voltage, 4 is a storage battery, and 5 is a key switch.

The operation of the conventional device configured as above will be explained.

First, when starting the internal combustion engine, when the key switch 5 is closed, base current is supplied from the storage battery 4 to the output transistors 302 and 303 via the key switch 5 and the resistor 304, and the output transistors 302 and 303 become conductive. A field current flows from the storage battery 4 to the field coil 102 through the output transistors 302 and 303, generating a field magnetomotive force.

When the engine is started in this state and the generator 1 is driven, an alternating current output is induced in the armature coil 101 according to its rotation speed.

This AC output is full-wave rectified by the full-wave rectifier 2.

Here, when the rectified output voltage is below a predetermined value, the resistor 310
．． Since the voltage dividing point potential of the voltage detecting voltage dividing circuit constituted by 311 is still low, the zener diode 306 maintains a non-conducting state, so that the output voltage of the generator 1 varies depending on the rotation of the generator 1. It is rising as the number rises.

After that, when the rotational speed of the generator 1 further increases and the output voltage accordingly exceeds a predetermined value, the voltage dividing point potential of the voltage dividing circuit also increases, thereby causing the zener diode 30
6 is conductive, a base current flows to the control transistor 305 through the diodes 309, 308, 307, and the Zener diode 306, and the control transistor 305 is conductive.

When the control transistor 305 becomes conductive, the output transistors 302 and 303 become non-conductive, the field current of the field coil 102 is cut off, and the output voltage of the generator 1 decreases.

When this output voltage drops below a predetermined value, the Zener diode 306 and transistor 305 become non-conductive again.
Transistors 302 and 303 conduct and the field coil 10
Since generator 2 is energized, the output voltage of generator 1 increases again.

By repeating the above-described operations, the output voltage of the generator 1 is controlled to a predetermined value, and the voltage of the storage battery 4 is controlled to a predetermined value using this controlled voltage.

Next, FIG. 2 is a characteristic curve showing the change in control voltage with respect to the change in ambient temperature of the conventional device shown in FIG. (-2 mV/°C 1 unit), so as shown in FIG. 2, the control voltage has a characteristic that it decreases linearly as the ambient temperature rises.

However, in the conventional device described above, the control voltage drops almost linearly as the ambient temperature rises, as shown in FIG. Even if you select and set the control voltage, charging tends to be insufficient at low temperatures.

In order to eliminate this drawback, the temperature compensation diode 30
7. If a diode is added to 308 and 309 to increase the temperature gradient, the voltage width will become too large in the low and high temperature ranges, reducing the lifespan and performance of in-vehicle electronic equipment (not shown). It had some drawbacks.

This invention provides an excellent charging generator control device that eliminates the above-mentioned drawbacks.

An embodiment of this invention shown in FIGS. 3 and 4 will be described below.

In FIG. 3, 312 is a reference voltage/temperature compensation diode for setting a second predetermined value in a medium temperature range, and a plurality of diodes are connected in series in the forward direction.

313 and 314 are resistors constituting a second voltage detection voltage divider circuit (hereinafter referred to as voltage divider circuit) that sets the second predetermined value, and 315 is a resistor that sets the first predetermined value in a low temperature range. This Zener diode is used for reference voltage and is called the first Zener diode.

316 and 317 are resistors constituting a first voltage divider circuit for setting the first predetermined device, 318 is a high temperature operation transistor inserted in series with the control transistor 305, and 319 is a third predetermined value. This is the Zener diode for the reference voltage used to set the voltage, and is called the second Zener diode.

320 and 321 are resistors constituting a third voltage divider circuit for setting the third predetermined value.

In FIG. 4, the period a-1) is referred to as a first predetermined value having a higher set value in the low temperature operating region.

l) -c is the medium temperature operating region and is called the second predetermined value.

The period between c and d is a high temperature operating region and is referred to as a third predetermined value.

The operation of the embodiment configured as above will be explained.

First, when the key switch 5 is closed to start the engine,
A base current is supplied from the storage battery 4 to the output transistors 302 and 303 via the key switch 5 and the resistor 304, and the output transistors 302 and 303 become conductive, and a field current flows through the field coil, generating a field magnetomotive force. do.

When the engine is started in this state, the generator 1 is driven and an alternating current output is induced in the armature 101.

This AC output is full-wave rectified by the full-wave rectifier 2, and the storage battery 4 is charged by this rectified output, but at this time, the ambient temperature of the voltage regulator 3 is in the low temperature range (Fig. 4 a-1).
(between), the voltage drop across the temperature compensation/reference voltage diode 312 is higher than the potential at the connection point between the resistors 313 and 314 that constitute the second voltage detection voltage divider circuit (hereinafter referred to as the detection circuit). The base-emitter voltage of the control transistor 305 and the collector voltage of the high-temperature operating transistor 318
Since it is lower than the sum of the emitter voltages, no base current flows to the control transistor 305 through the diode 312.

On the other hand, the potential at the connection point of the resistors 320 and 321 constituting the third detection circuit is higher than the sum of the zener voltage of the second zener diode 319 and the base-emitter voltage of the high-temperature operation transistor 318. The second zener diode 319 is conducting.

Therefore, the resistors 316 and 317 forming the first detection circuit
The first zener diode 315
and the control transistor 305 turns on and off to control the generator 1.
The output voltage is controlled to a first predetermined value (between a-1 in FIG. 4).

At this time, if the first Zener diode 315 is selected to have a small temperature gradient, the control voltage will hardly change with respect to temperature changes.

Next, the ambient temperature of the voltage regulator 3 rises to a medium temperature range (fourth temperature range).
(b-0), the forward voltage drop of the diode 312 decreases and the predetermined value by the second detection circuit becomes the first
is below a predetermined value, the control transistor 305 is turned on and off through the diode 312 to control the output voltage of the generator 1 to a second predetermined value (between b and c in FIG. 4).

At this time, the reference voltage is based on the diode 312, so the temperature gradient is -0.1 to 0.15 V/1, which is the conventional general temperature gradient.
It is larger than 0°C and becomes more than -0.4V/10°C.

Furthermore, the ambient temperature of the voltage regulator 3 rises, and the high temperature range (
3), the forward voltage drop of the diode 312 further decreases, and the predetermined value determined by the second detection circuit becomes equal to or less than the third predetermined value.

Therefore, the diode 312 and the control transistor 305 remain conductive, and the resistor 32, which now constitutes the third detection circuit,
The connection point voltage of 0.321 turns on and off the second zener diode 319 and the high-temperature operation transistor 318, thereby increasing the output voltage of the generator 1 to a third predetermined value (Fig. 4,
between c and d).

At this time, if the second Zener diode 319 is selected to have a small temperature gradient, the control voltage will hardly change with respect to changes in temperature.

As mentioned above, this invention has extremely great practical effects because the entire circuit can be easily integrated into an IC without requiring any special elements.

In addition, a higher voltage is maintained almost constant in a low temperature range, and a lower voltage is maintained almost constant in a high temperature range.

In addition, the medium temperature range is the conventional general temperature gradient (-0, 1 to 0.
15V/10°C), a very large value (-0,4
V/10°C or higher), it not only improves the charging characteristics of the storage battery, but also reduces the width of the control voltage in the low and high temperature ranges, which has the advantage of preventing shortened life and performance of in-vehicle electronic equipment. There is.

In addition, the first, which operates respectively at low temperature, medium temperature, and high temperature,
It has second and third detection circuits, the one of the first and second detection circuits that is lower operates, and the third detection circuit is activated when the higher the first and second detection circuits are. Since the controller is entirely composed of semiconductors, these control parts are made into semiconductor ICs so that they can be adjusted.

However, it can be made into one chip, which has the advantage of higher reliability and lower cost.

[Brief explanation of drawings]

Fig. 1 is an electric circuit diagram showing a conventional device, Fig. 2 is a characteristic diagram of the conventional device, Fig. 3 is an electric circuit diagram showing an embodiment of this invention, and Fig. 4 is a characteristic diagram of the embodiment shown in Fig. 3. It is. In the figure, 1 is a charging generator, 101 is an armature coil, 102
is a male magnetic coil, 2 is a full-wave rectifier, 3 is a voltage regulator,
301 is a diode, 302.303.305.318
is a transistor, 304.313.314.316.3
17.320° 321 is a resistor, 315.319 is a Zener diode, 312 is a plurality of diodes, 4 is a storage battery,
5 is a key switch. The relevant portions are shown in each figure. Same symbols are the same or similar.

Claims (2)

[Scope of utility model registration request] (1) A storage battery is charged by the rectified output of an AC charging generator having a field coil, and the output voltage of the AC charging generator is set to a predetermined value by intermittent control of the field current flowing through the field coil. and a semiconductor voltage regulator that controls the temperature, and divides the change characteristics of the predetermined value with respect to changes in ambient temperature into three regions: a low temperature range, a medium temperature range, and a high temperature range, and keeps the higher voltage almost constant in the low temperature range. A first predetermined value is maintained, a third predetermined value is maintained at a lower voltage approximately constant in a high temperature range, and a temperature gradient connecting the first and third predetermined values is provided in a medium temperature range. In the AC charging generator control device that performs voltage adjustment by combining a plurality of voltage detection units with different temperature characteristics in order to obtain each of these predetermined temperature characteristics as a second predetermined value, the semiconductor voltage adjustment device includes: an output transistor inserted in series with the field coil to intermittent the field current; a control transistor for controlling the output transistor intermittently; a transistor for high temperature operation inserted in series with the control transistor; a first Zener diode that operates within a predetermined value range and whose anode side is connected to the base of the control transistor and turns on and off the control transistor; and a voltage dividing point is connected to the cathode side of the first Zener diode. a first voltage detection voltage dividing circuit; and at least one forward-connected circuit that operates within the second predetermined value range and whose cathode side is connected to the base of the control transistor to control on/off of the control transistor. a second voltage detecting voltage dividing circuit having a voltage dividing point connected to the anode side of the diode and the third predetermined value range, and the anode side thereof being connected to the base of the transistor for high temperature operation. a second zener diode that is connected and controls on/off the high temperature operation transistor;
A charging generator control device comprising: a third voltage detection voltage dividing circuit having a voltage dividing point connected to the cathode side of the zener diode. (2) Utility model registration In the product described in claim (1), the temperature gradient of the second predetermined value in the medium temperature range is set to that of a conventional device (-0.10 to -0.15V/10°C). ) A charging generator control device characterized by having a very large value (-0.4V/10°C or more) compared to