JPH06311800A - Generating controller for generator - Google Patents

Abstract

PURPOSE:To effectively control an exciting current and to easily release this control function. CONSTITUTION:A bias resistor 274 is connected between an L terminal and an IG terminal of a voltage controller 2. The resistor 274 biases an L terminal voltage substantially to a battery voltage at the time of cutting OFF a transistor 281. The L terminal voltage becomes a voltage between a collector and an emitter of the transistor 281 at the time of driving a charge lamp 5. An exciting current limiter 25 turns on a transistor 254 when the exciting current is a predetermined value or more, thereby holding an output transistor 24 in a cut-off state. An inhibiting circuit 27 turns on a transistor 273 when the L terminal voltage is Ve or lower which is lower than the voltage between the collector and the emitter of the transistor 281, thereby cutting OFF the transistor 254 of the limiter 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a generator control device capable of canceling the function of controlling an exciting current of a generator as needed.

[0002]

2. Description of the Related Art A control device for canceling the exciting current limiting function of a generator is disclosed in, for example, Japanese Utility Model Laid-Open No. 63-88044. The device of this publication disables the operation of the exciting current limiting circuit by turning off the power source of the exciting current limiting circuit by an external switch.

[0003]

However, according to the above-mentioned prior art, since the exciting current limiting circuit is connected to the power source through the display lamp, the power source of the exciting current limiting circuit remains the same even when the indicator lamp is cut off. Will be cut off. Therefore, the output of the generator cannot be suppressed, and for example, the current of the charging line becomes excessively large, which causes burning or burning of the charging line, or the increase of the generator torque due to the increase of the charging current adversely affects the engine rotation (the worst case. In the case of, or invite an engine stall).

Therefore, an object of the present invention is to provide a structure in which the exciting current limiting circuit can be operated reliably and the function can be easily released.

[0005]

In order to achieve the above object, the present invention provides a first switch means for connecting and disconnecting an exciting current of a generator, and an opening / closing control of the first switch means to control the exciting current. Voltage control means for controlling the output voltage of the generator to a first predetermined voltage by intermittent control, current control means for controlling the opening / closing of the first switch means to suppress the exciting current, and open to the outside. Second switch means connected in series with the power generation display means via a connection part, and the second switch means when the power generation voltage of the generator is equal to or lower than a second predetermined voltage which is lower than the first predetermined voltage. The power generation detection means for driving the power generation display means by conducting the, and the voltage of the connection portion,
A prohibiting means for prohibiting the current control of the current controlling means when the third predetermined voltage is less than the voltage across the switching means when the second switching means is conducting, and at least when the power generation display means is not driven. Biasing means for biasing the voltage of the connection portion to a value higher than the third predetermined voltage.

[0006]

When the power generation voltage of the generator is equal to or lower than the second predetermined voltage, the power generation detection means causes the second switch means to conduct, and the power generation display means is driven. At this time, the voltage of the connection portion has a value of at least the voltage across the second switch means,
Therefore, since the voltage is higher than the third predetermined voltage, the prohibiting means does not prohibit the excitation current control.

On the other hand, when the generated voltage is equal to or higher than the second predetermined voltage, the second switch means shuts off and the power generation display means stops. At this time, since the voltage of the connection portion is biased to a value higher than the third predetermined voltage by at least the power generation display means, the prohibition means does not prohibit the excitation current control. Further, the bias means does not prohibit the excitation current control when the power generation display means is disconnected.

The connecting portion is open to the outside,
It is easy to drop the voltage of this portion to the third predetermined value or less by an operation such as grounding from the outside.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment in which the present invention is applied to a vehicle AC generator will be described below with reference to the drawings. (First Embodiment) FIG. 1 is an electric circuit diagram showing a first embodiment of a power generation control device for an automotive alternator to which the present invention is applied. The three-phase AC generator 1 is driven by an engine (not shown), and receives an electric current to generate a magnetic field, an exciting coil 11, an armature coil 12 that generates electric power by the magnetic field of the exciting coil 11, and an armature coil 12. The rectifier 13 for rectifying the AC current of the above into a DC is provided, and the output of the rectifier 13 is supplied to the battery 3 and each electric load 4 of the vehicle. The output of the generator 1 changes depending on the rotation speed of the engine and the energization amount (excitation current value) of the exciting coil 11. Then, the exciting current flowing through the exciting coil 11 is controlled by the power generation control device 2.

The power generation control device 2 includes a voltage adjusting circuit 200,
Output transistor (first switch means) 24, exciting current limiting circuit 25, freewheeling diode 26, inhibiting circuit 27,
A charge lamp drive circuit (power generation detection means) 28 is provided,
These are formed in the same circuit board shape and housed in the same case. IG, L, B, F, E and P are connection terminals provided on the case.

The voltage adjusting circuit 200 will be described with reference to FIG. As shown in FIG. 2, the voltage adjustment circuit 200 includes a generated voltage detection circuit 21 and a smoothing circuit 22. It should be noted that 201 to 203 in FIGS. 1 and 2 are connection portions shown in order to clarify the connection relationship between the circuits in both drawings. The generated voltage detection circuit 21 will be described. Voltage dividing resistors 211 and 211
Reference numeral 12 divides the output voltage of the generator 1. Comparator 213
Compares the divided voltage Vd by the voltage dividing resistors 211 and 212 with a predetermined value Va, and outputs a Hi signal when the divided voltage Vd is larger than the predetermined value Va.

The smoothing circuit 22 will be described. This circuit is a circuit that charges and discharges the smoothing capacitor 226 according to the outputs of the generated voltage detection circuit 21 and the excitation current limiting circuit 25, and controls the opening and closing of the switch 24 according to the terminal voltage of the smoothing capacitor 226. The opening / closing control signal to the switch 24 is delayed by 226. The constant current source 224 keeps the smoothing capacitor constant current (I224
) To charge. The transistor transistor 222 is driven by the output signal of the comparator 213 of the generated voltage detection circuit 21, and turns on when the output signal is at the Hi level. Constant current source 223
Operates when the transistor 222 is ON, and discharges the smoothing capacitor 226 with a constant current (I223). The constant voltage diode 225 determines the maximum charging voltage of the smoothing capacitor 226. The voltage dividing resistors 227, 228, 229 divide the constant voltage source Vco to generate the reference voltage Vr.

The transistor 232 compares the reference voltage Vr with the terminal voltage V226 of the capacitor 226, and turns on when the terminal voltage V226 of the capacitor 226 is higher than the reference voltage Vr to change the voltage division ratio of the reference voltage Vr. In this embodiment, the reference voltage Vr is set to the voltage VrH obtained by dividing the constant voltage source Vco with the resistors 227 and 228 when the comparator 231 outputs the Lo signal, and the comparator 231 outputs the Hi signal. In this case, the voltage dividing ratio is reduced by the transistor 232 and the resistor 229, and is set to VrL lower than VrH.

The driving resistor 221 transmits the signal of the comparator 213 to the transistor 222. The drive resistor 230 transmits the signal of the comparator 231 to the transistor 232. The drive resistor 233 outputs the signal of the comparator 213 to the output transistor 24.
Communicate to. Constant current I22 by constant current sources 223 and 224
3, I224 are set in a relation of I223> I224, and the smoothing capacitor 226 is charged with a constant current I224 when the generated voltage Vd is lower than a predetermined value, and is constant (I223-I224) when the generated voltage Vd is higher than the predetermined value. It is discharged by electric current.

A description will be given below with reference to FIG. The output transistor 24, the output of the smoothing circuit 22 is energized exciting coil 11 is turned ON at the time of H _i, the output of the smoothing circuit 22 OF
When it is F, it is turned off to cut off the exciting coil 11. The excitation current limiting circuit 25 will be described. The resistor 251 detects the exciting current flowing through the output transistor 24. The comparator 252 compares the voltage Vc corresponding to the exciting current detected by the resistor 251 with a predetermined voltage Vb (= equivalent to the exciting current Ib), and outputs a Hi signal when the detected voltage Vc is higher than the predetermined voltage Vb. . The collector of the transistor 254 is connected to the smoothing capacitor 226 of the smoothing circuit 22 and is turned on by the Hi output of the comparator 252 to discharge the electric charge of the smoothing capacitor 226 of the smoothing circuit. That is, when the exciting current is larger than the predetermined value (Ib), the transistor 25
4 is turned on and the smoothing capacitor 226 is instantly discharged. The drive resistor 253 transmits the output signal of the comparator 252 to the transistor 254.

The return diode 26 returns the exciting current when the output transistor 24 is turned off. The prohibition circuit 27 will be described. The comparator 272 compares the L terminal voltage with the predetermined voltage Ve, and outputs the H _i signal when the L terminal voltage is smaller than the predetermined voltage Ve. The transistor 273 is turned on by the H _i output of the comparator 272, and the transistor 254 of the exciting current limiting circuit 25 is turned off. That is, the inhibition circuit 27 includes the smoothing capacitor 2 formed by the transistor 254.
This circuit releases the restriction of the exciting current by prohibiting the discharge of 26. Incidentally, 271 is an input resistance, and 274 is a bias resistance (bias means). The predetermined voltage Ve
Is set to a voltage lower than the collector-emitter voltage V _CE (sat) when the transistor 281 described later is turned on and higher than the ground voltage.

The charge lamp drive circuit 28 will be described. The voltage detection circuit 282 is used for the armature winding 12 of the generator 1.
The one-phase voltage is detected, and the _L0 signal is output when the one-phase voltage is equal to or higher than a predetermined value. The transistor 281 is turned on by the H _i signal of the voltage detection circuit 282 to turn on the charge lamp 5 via the key switch 6. Next, the operation of the above embodiment will be described.

When the key switch 6 is closed and the engine is stopped, the generator 1 is not generating power.
The voltage detection circuit 282 of the charge lamp drive circuit 28 is H level.
Output _i signal. Therefore, the transistor 281 is turned on.
Then, the power of the battery 3 is supplied to the charge lamp 5, and the charge lamp 5 is turned on. When the engine starts, the generator 1 starts to generate power, and when the generated voltage reaches a predetermined value, the output signal of the voltage detection circuit 282 becomes L _O. Therefore, the transistor 281 is turned off and the charge lamp 5 is turned off.

During the period from the turning on of the charge lamp 5 to the time immediately before turning off, the L terminal voltage is the transistor 28.
1 collector - a emitter voltage V _CE (sat), the output signal of the comparator 272 of the inhibit circuit 27 is L _O. Therefore, the transistor 273 is OFF, and the exciting current limiting function of the exciting current limiting circuit 25 is not released. At that time, even if the charge lamp 5 is turned off, the L terminal voltage is biased to almost the terminal voltage of the battery 3 by the bias resistor 274, and the output signal of the comparator 272 of the inhibition circuit 27 is L _O. Therefore, the transistor 273 is OFF, and the exciting current limiting function of the exciting current limiting circuit 25 is not released.

After the charge lamp 5 is extinguished, the parallel circuit of the charge lamp 5 and the bias resistor 274 biases the L terminal voltage to approximately the terminal voltage of the battery 3, and when the charge lamp is burned out, the bias resistor 274.
Since the L terminal voltage is biased almost to the terminal voltage of the battery 3 only by this, the exciting current limiting function of the exciting current limiting circuit 25 is not released.

As described above, the exciting current limiting function of the exciting current limiting circuit 25 is not normally released, but if the L terminal is grounded so that the output of the comparator 272 becomes H _i , this can be released. You can Therefore, by grounding the L terminal as needed, the output performance of the generator 1 can be inspected without limiting the exciting current. Hereinafter, description will be given using the time charts shown in FIGS. 3 and 4.

First, the operation when the exciting current is below a predetermined value will be described with reference to FIG. Divided voltage V of generator output voltage
When d is lower than a preset predetermined value Va, the output of the comparator 213 (output of the generated voltage detection circuit 21) is L.
At o, the smoothing capacitor 226 is charged by the constant current source 224, the terminal voltage V226 of the capacitor 226 gradually rises, and finally the falling voltage VZ of the constant voltage diode 225.
Rise to. At this time, the terminal voltage V22 of the capacitor 226
Since 6 is higher than the reference voltage VrL, the exciting coil driving switch 24 is ON, the exciting current increases, and the generator output also increases.

The divided voltage Vd of the generator output voltage is the predetermined value V
When a is exceeded (between A and C in the figure), the comparator 213 becomes Hi.
The signal is output, and the smoothing capacitor 226 makes the constant current source 22
3, 224 discharges with a constant current (I223-I224) to gradually decrease the terminal voltage V226, and finally to OV. The switch 24 is a divided voltage V of the generator output voltage.
From the point A where d exceeds a predetermined value Va, the smoothing capacitor 226
Td.OF from the voltage of VZ to the voltage of VrL
It switches to OFF at point B delayed by the time of F.

When the switch 24 is turned off, the exciting current decreases and the generator output voltage also decreases. When the generator output voltage decreases and the divided voltage Vd again becomes equal to or lower than the predetermined value Va (between C and E in the figure), the output of the comparator 213 becomes Lo, and the smoothing capacitor 226 and the constant current source 224 also. The terminal voltage V226 rises as time goes by, and finally VZ
Reach the voltage. At this time, the switch 24 is set to V22 after the divided voltage Vd of the generator output voltage becomes equal to or lower than the predetermined value Va.
Time to charge 6 from OV to VrH voltage Td.ON
It switches to ON at point D delayed by the time.

In this way, the switch 24 delays the output signal of the comparator 213 by the delay time T preset in the smoothing circuit.
OFF / ON control is performed with a delay of d.OFF and Td.ON. The delay time at this time can be expressed by the following equation.

[0026]

[Number 1] _{Td.OFF = C (V Z -VrL)} / (I223 -I224), Td.ON = C · VrH / I224 C is the capacitance of the smoothing capacitor 226. Even if the exciting current is less than the predetermined value (Ib), the switch 24 is turned on.
While the voltage is generated in the exciting current detecting resistor 251, the voltage is smaller than the predetermined voltage Vb.
Is off and does not affect the control of the switch 24.

Next, the operation when the exciting current reaches the predetermined value (Ib) before the divided voltage Vd of the generator output voltage reaches the predetermined value Va will be described with reference to FIG. Since the divided voltage Vd of the generator output voltage is smaller than a predetermined value Va, the output becomes Lo smoothing capacitor 226 of the comparator 213 terminal voltage V226 is charged by the constant current source 224 rises to V _Z. At this time, the switch 24 is ON, the exciting current increases with time, and the terminal voltage Vc of the exciting current detecting resistor 251 also rises.

Therefore, at the point F in the figure, the exciting current detecting resistor 25
When the terminal voltage Vc of 1 exceeds the predetermined value Vb, the transistor 254 is turned on to instantly discharge the electric charge of the smoothing capacitor 226, and the terminal voltage V226 is lowered to OV. As a result, the terminal voltage V226 of the smoothing capacitor 226 becomes lower than VrL and the switch 24 is turned off. When the switch 24 is turned off, the terminal voltage Vc of the exciting current detection resistor 251 becomes OV, so that the transistor 254 is also turned off.

When the transistor 254 is turned off, the smoothing capacitor 226 is charged by the constant current source 224 again, the terminal voltage V226 rises, and the time TOFF (TOFF = Td) until the voltage of VrH is reached (point G in the figure). During the OFF period, the switch 24 is turned off, and the exciting current flowing through the exciting coil 11 during this time is reduced while circulating through the freewheeling diode 26. The terminal voltage V226 of the smoothing capacitor 226 is V
_{When rH} is exceeded, the output of the comparator 231 is inverted and becomes Hi output, and the switch 24 is turned on, so that the exciting current is again
When it increases and reaches a predetermined value (Ib), the switch 24 is turned off for the TOFF time and the exciting current decreases. While repeating such operations, the exciting current is controlled to a value equal to or lower than the predetermined value (Ib). The same effect can be realized by the configuration of the smoothing circuit in which the charging / discharging relationship of the capacitor 226 of the embodiment is reversed.

(Second Embodiment) FIG. 5 is an electric circuit diagram showing a second embodiment. In the second embodiment, a transistor 275 is applied instead of the bias resistor 274 of the first embodiment, and the other circuit configuration is the same as that of the first embodiment. The transistor 275 is turned on when the lamp driving transistor 281 is turned off. When the transistor 275 is turned on, the L terminal voltage becomes almost the same as the terminal voltage of the battery 3, and the comparator 2
Since the output of 72 is maintained at L _O , the exciting current limiting function of the exciting current limiting circuit 25 is not released.

(Third Embodiment) FIG. 6 is an electric circuit diagram showing a third embodiment. In this third embodiment, instead of providing a bias element between the IG and L terminals as in the first and second embodiments, a diode 276 connected between the inverting input terminal of the comparator 272 and ground is applied. The other circuit configurations are the same as those in the first and second embodiments. The diode 276 raises the L terminal voltage by the diode drop when the discharge current of the comparator 272 is supplied (value equal to or higher than a predetermined voltage Ve), and maintains the output of the comparator 272 at L _O. The same effect can be obtained by applying a Zener diode whose anode side is grounded instead of the diode 276.

Further, according to the first and second embodiments described above, the L terminal voltage can be maintained at a predetermined voltage even if the charge lamp 5 burns out. Even if connected, a stable voltage can be supplied, and these devices can be driven without malfunction. Further, the exciting current control means is not limited to the above-mentioned means for limiting the exciting current, and may be, for example, means for suppressing the increasing rate of the exciting current. Further, both means may be provided.

(Fourth Embodiment) FIG. 7 is an electric circuit diagram showing a fourth embodiment. The fourth embodiment is an example in which the exciting current control means includes the above-mentioned means for limiting the exciting current and means for suppressing the increasing rate of the exciting current. Incidentally, FIG.
Shows only the power generation control device 2, and the other circuit configurations are the same as those shown in FIG. Further, components having the same reference numerals as those in FIG. 1 have the same configuration, and the description thereof will be omitted.

A means (hereinafter referred to as "gradual excitation means") 29 for suppressing the increasing speed of the exciting current outputs a pulse signal to the AND circuit 30 whose duty ratio gradually increases. The output signal from the drive resistor 233 of the voltage adjusting circuit 200 is input to the AND circuit 30. With the above configuration, the voltage adjusting circuit 20
When the output from 0 is Hi, the pulse signal of the duty corresponding to the pulse signal of the gradual excitation means 29 is output from the AND circuit 30, and the output transistor 24 is turned ON / OFF. Therefore, the exciting current is suppressed so as to gradually increase as the duty ratio of the output signal of the gradual exciting means increases.

The output signal of the comparator 272 of the inhibition circuit 27 is also input to the gradual excitation control means 29, and the gradual excitation is controlled by grounding the L terminal like the excitation current limiting circuit 25 of each embodiment. The operation of the excitation means 29 is stopped. That is, the Hi signal of the comparator 272 outputs the Hi signal to the AND circuit 30.

[0036]

As described above, according to the present invention, when the power generation display means is driven by the conduction of the second switch means, the voltage of the connection portion is at least higher than the voltage across the second switch means. Since it is larger than the third predetermined voltage, the exciting current control is executed without being prohibited by the prohibiting means, and at least when the power generating display means is stopped due to the interruption of the second switch means, the connecting portion is made by the power generating display means. Is biased to a value higher than the third predetermined voltage, the exciting current control is executed without being prohibited by the prohibiting means, and the voltage of the connecting portion is changed to the first value by the biasing means when the power generation display means is disconnected. Since it is biased to a value larger than the predetermined voltage of 3, the prohibiting means executes the exciting current control without being prohibited.

Therefore, due to the energization of an excessive excitation current, an excessive current is applied to the charging line, and the charging line is burned down.
It is possible to prevent the engine rotation from becoming unstable (in the worst case, causing engine stall) due to an increase in generator torque due to an increase in charging current. Further, since the connecting portion is open to the outside, it is possible to easily perform an external operation such as grounding on this portion to reduce the voltage of the portion to the third predetermined voltage or less, and to suppress the excitation current control by the prohibiting means. Prohibition can be done easily. Therefore, the excitation current control can be prohibited and the output performance of the generator can be inspected if necessary.

[Brief description of drawings]

FIG. 1 is an electric circuit diagram showing a first embodiment of the present invention.

FIG. 2 is an electric circuit diagram showing a voltage adjusting circuit of the first embodiment.

FIG. 3 is a time chart for explaining the operation of the first embodiment.

FIG. 4 is a time chart for explaining the operation of the first embodiment.

FIG. 5 is an electric circuit diagram showing a second embodiment of the present invention.

FIG. 6 is an electric circuit diagram showing a third embodiment of the present invention.

FIG. 7 is an electric circuit diagram showing a fourth embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Three-phase AC generator 2 Power generation control apparatus 11 Excitation coil 21 Generation voltage detection circuit (voltage adjustment means) 22 Smoothing circuit (voltage adjustment means) 24 Output transistor (first switch means) 25 Excitation current limiting circuit (current control means) ) 27 inhibit circuit 274 bias resistor (bias means) 28 charge lamp drive circuit (power generation detection means) 281 charge lamp drive transistor (second switch means) 29 gradual excitation means (current control means)

Claims (1)

[Claims] 1. A first switch means for connecting / disconnecting an exciting current of a generator, and an opening / closing control of the first switch means for controlling the connecting / disconnecting of the exciting current so that an output voltage of the generator is a first predetermined value. A voltage adjusting unit that adjusts the voltage, a current control unit that controls the opening and closing of the first switch unit to suppress the exciting current, and a first unit that is connected in series with the power generation display unit via a connection portion opened to the outside. A second switch means; a power generation detection means that conducts the second switch means to drive a power generation display means when the power generation voltage of the generator is equal to or lower than a second predetermined voltage that is lower than the first predetermined voltage; Prohibiting means for prohibiting current control of the current controlling means when the voltage of the connecting portion is equal to or lower than a third predetermined voltage which is smaller than the voltage across the switching means when the second switching means is conducting; Other than means Bias means for biasing the voltage of the connection portion to a value higher than the third predetermined voltage, and a power generation control device for a power generator.