JPH0739200A - Voltage controller for automotive generator - Google Patents

Abstract

PURPOSE:To provide a voltage controller for an automotive generator having high operating reliability irrespective of shared use of an input terminal for a conduction command signal of an exciting current and a control characteristic alteration (generating voltage switching) command signal of a voltage controller. CONSTITUTION:A voltage controller 6 intermittently controls an exciting current in response to a generated voltage to control the generated voltage of a generator to a predetermined level. A conducting command signal for instructing conduction of an exciting current and a generating voltage switch command signal for instructing switching of a generated voltage are input to a command signal input terminal (C terminal). A generation detector 10 detects generating of the generator. A conducting instruction unit 11 instructs an exciting current conduction to a voltage controller 6 based on the conduction command signal to be input to the input terminal C in the case of stopping generation, a generation switching instruction unit 5 instructs switching of the generated voltage to the controller 6 based on the command signal to be input to the terminal C during generating.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voltage control device for a vehicular generator, and more particularly to a single input for receiving a command signal for instructing energization of an exciting current and change of a voltage control characteristic for controlling an output voltage of the generator. The present invention relates to a voltage control device for a vehicle generator having a terminal.

[0002]

2. Description of the Related Art In a conventional voltage control device for a vehicle generator, an input terminal for inputting an energization command signal for instructing energization of an exciting current (start of power generation) and a change in voltage control characteristic (for example, generator output) Change the target level of voltage)
It has been proposed to separately have an input terminal to which a control characteristic change command signal for instructing is input and to start power generation and change the control characteristic based on both command signals input to these input terminals. The control characteristic change is issued from, for example, an ECU (engine control unit), and the target value of the output voltage of the generator is set to suppress torque fluctuation of the engine and torque assist (power generation suppression) during climbing. This is performed in various cases such as changing the speed or limiting the changing speed of the exciting current.

Japanese Patent Application Laid-Open No. 60-666 filed by the present applicant
In the '98 publication, the energization command signal and the generator output voltage target level change command signal having different voltages are input to a single input terminal (hereinafter referred to as C terminal), and the signal voltage input to this input terminal is It is disclosed to distinguish between the energization command signal and the generator output voltage target level change command signal by discriminating between two different threshold voltages. By doing so, it is possible to reduce the number of terminals of the power generation control device.

Explaining one example in detail with reference to FIG. 6, Vth1 is a conduction threshold voltage of the exciting current, and Vth1
th2 is a threshold voltage for changing the target voltage level. Here, if the C terminal voltage exceeds Vth1, the exciting current is energized to set the output voltage target level of the generator to the low level VL, and if the C terminal voltage exceeds Vth2, the exciting current remains energized. , The output voltage target level of the generator is set to the high level VH. The low level VL is a predetermined low voltage including the output current stop state of the generator, and the high level VH is a predetermined voltage higher than the low level VL.

[0005]

However, in the above-mentioned voltage control device of the common input terminal type, although it is possible to save the number of input terminals, the C terminal voltage is a voltage of a plurality of threshold voltages of three or more types. The margin for determining the state becomes small, and the malfunction probability increases due to external noise, fluctuations in temperature and power supply voltage, etc., so the noise resistance characteristics of the circuit are improved and characteristic fluctuations due to temperature and power supply voltage are correspondingly increased. The problem arises that deterrence must be sought.

The present invention has been made in view of the above problems, and shares the input terminal of the energization command signal for the exciting current and the control characteristic change command signal for changing the voltage control characteristic of the output voltage of the generator. First, it is an object of the present invention to provide a voltage control device for a vehicle generator having high operation reliability.

[0007]

A voltage control device for a vehicle generator according to the present invention includes a voltage control section for intermittently controlling an exciting current according to an output voltage of a generator to control the output voltage to a predetermined level. A command signal input terminal for inputting an energization command signal for instructing energization of the exciting current and a control characteristic change command signal for instructing a change in control characteristics of the voltage control unit; and the command signal input terminal for inputting from the command signal input terminal. In a voltage control device for a vehicle generator, comprising: a command control unit that commands the voltage control unit to energize the exciting current and change the control characteristic based on both signals, the command control unit detects power generation. , A power generation detection unit that outputs a power generation detection signal, and in the case of power generation, instructing the voltage control unit to energize an exciting current based on the power generation detection signal from the power generation detection unit, and in the case of power generation stop, The command signal An energization command unit that commands the voltage control unit to energize the excitation current based on the energization command signal input to the input terminal, and the power control unit based on the control characteristic change command signal input to the command signal input terminal during power generation. A voltage control device for a vehicle generator, comprising: a control characteristic change command unit for instructing a change of control characteristics of the voltage control unit.

[0008]

The voltage control section intermittently controls the exciting current according to the generated voltage to control the generated voltage of the generator to a predetermined level.
The command signal input terminal (C terminal) receives an energization command signal for commanding energization of the exciting current and a control characteristic change command signal for commanding a change in the control characteristic of the voltage controller. The command control unit includes a power generation detection unit, an energization command unit, and a control characteristic change command unit. The power generation detection unit detects that the generator is generating power and commands the voltage control unit to energize the exciting current.

The energization command unit commands the voltage control unit to energize the exciting current based on the energization command signal input to the command signal input terminal when the power generation is stopped. The control characteristic change command unit issues an instruction to change the control characteristic of the voltage control unit based on the control characteristic change command signal input to the command signal input terminal during power generation.

[0010]

As described above, the voltage control device for a vehicle generator of the present invention inputs the energization command signal and the control characteristic change command signal of the voltage control unit to the command signal input terminal (C terminal). At the same time, it is detected whether power is being generated, and if power is being generated, the C terminal input signal is regarded as a control characteristic change command signal and the control characteristic is changed (for example, the voltage target level is changed).
Since the C terminal input signal is regarded as the energization command signal and the energization of the exciting current is commanded when the power generation is stopped, it is necessary to distinguish both of the above command signals by the voltage level. Therefore, it is not necessary to reduce the discrimination margin of the both command signals.

That is, according to the present invention, the energization command signal is input to the command signal input terminal only when the generator is not generating power, while the command signal for changing the control characteristics of the voltage control unit is input only during power generation, and power is being generated. This is based on the knowledge that the type of C terminal input signal can be specified by determining whether or not it is. Therefore, according to the present invention, it is possible to realize a voltage control device for a vehicular generator capable of achieving both reduction in the number of terminals and improvement in operational reliability.

[0012]

Embodiment 1 An embodiment of the present invention will be described with reference to FIG. 1 is a regulator (voltage control device) that controls the output voltage of a generator 2 driven by an engine (not shown), and 30 is a battery that is charged from the generator 2 through a charging line 100.

The generator 2 comprises a three-phase stator coil 24, a three-phase full-wave rectifier 20 for rectifying the voltage generated by the stator coil 24, and an exciting coil 21. Reference numeral 7 is an electric load connected to the high end of the battery 30, and the low ends of these are electrically grounded. The C terminal (command signal input terminal in the present invention) of the regulator 1 is connected to the engine control unit (EC
U) 3 inputs a signal (energization command signal and control characteristic change command signal in the present invention) Vc. The battery voltage is input to the ECU 3 through the ignition switch 4.

The C terminal is connected to the + input terminal of the comparator 11 and the input terminal of the voltage switching circuit 5, and the comparator 1
The output of 1 is connected to the base of the grounded-emitter npn transistor 8 through the OR circuit 9 and the base current limiting resistor r1, and the collector thereof is connected to the base of the grounded-emitter pnp transistor 12 through the base current limiting resistor r2. The emitter of the transistor 12 is connected to the internal power supply line HL, and the collector thereof is connected to the reference voltage line 300 through the resistor r3.

The reference voltage line 300 is maintained at a predetermined reference potential Vr by the Zener diode 13, and this reference voltage Vr is applied as a power supply voltage to the voltage switching circuit 5 and further applied to the base of the switching transistor 6 through the resistor r4. Has been done. A rectified power generation voltage (output voltage of the power generator 2) is applied to the internal power supply line HL from the generator 2, and the voltage of the internal power supply line HL, that is, the rectified power generation voltage is divided by a voltage dividing circuit including resistors r5 and r6. It is pressed and applied to the + input terminal of the comparator 17. The output voltage Va of the voltage switching circuit 5 is applied to the-input terminal of the comparator 17, the output voltage of the comparator 17 is applied to the base of the grounded-emitter npn transistor 18,
Its collector is connected to the base of the switching transistor 6. D1 is a flywheel diode.

The one-phase generated voltage of the three-phase stator coil 24 is smoothed by the smoothing circuit composed of the resistor r7 and the capacitor C through the P terminal, and then applied to the + input terminal of the comparator 10, and the − input terminal of the comparator 10. A reference voltage V1 is applied to. The reference voltage V2 is applied to the negative input terminal of the comparator 11. This operation will be described below.

When the ignition switch 4 is turned on before the engine is started, the ECU 3 outputs a high level potential signal (energization command signal) to the C terminal. Then, the comparator 11 turns on the transistor 8 and the transistor 8
Turns on the transistor 12. The battery voltage is applied to the internal power supply line HL through the charging line 100, the reference voltage line 300 is supplied with power from the internal power supply line HL through the transistor 12, and the reference voltage line 30 is supplied.
0 becomes the reference voltage Vr.

At this point, the voltage switching circuit 5 also has C
Since the high level voltage is input from the terminal, the voltage switching circuit 5 outputs the high level voltage to the negative input terminal of the comparator 17. On the other hand, since the power generation has not started yet, the charging line 100 is connected to the + input terminal of the comparator 17,
The battery voltage at a low level is divided from the rectified power generation voltage to be supplied with power, and the comparator 17 outputs a low level.

Then, the transistor 18 is turned off, the transistor 6 is turned on, and the exciting current is supplied to the exciting coil 21. After the engine starts, the generator 2 generates electricity and the charging line 1
When the charging of the battery 30 is started through 00, the comparator 17 divides the rectified generated voltage and the voltage switching circuit 5
Is compared with the reference output voltage from the transistor, and the transistor 6 is turned on and off based on the comparison result to hold the rectified generated voltage at a predetermined level (for example, 14.5 V).

The one-phase generated voltage of the three-phase stator coil 24 is smoothed by the smoothing circuit composed of the resistor r7 and the capacitor C through the P terminal to become the one-phase smoothed generated voltage Vp. This voltage Vp is compared with the reference voltage V1 by the comparator 10, but since Vp> V1 in the normal power generation state,
At the time of power generation, a high-level signal is output through the OR circuit 9, the transistors 8 and 12 are turned on, and the reference voltage line 300 is supplied even after the input of the energization command signal from the ECU is completed.
To keep the power supply to.

Next, the operation when the generated voltage switching command signal is input from the ECU 3 as the control characteristic change command signal will be described. The ECU 3 naturally outputs this power generation voltage switching command signal after the engine operation starts, that is, after the power generation starts. This power generation voltage switching command signal is executed for suppressing power generation for torque assist during uphill or stopping power generation output as described above, and such power generation adjustment is well known and the gist of this embodiment. Therefore, the description is omitted.

In this embodiment, the generated voltage switching command signal is composed of a high level potential signal and a low level potential signal lower than the high level potential signal. The high-level potential signal of the power generation voltage switching command signal is for outputting a normal rectified power generation voltage (14.5V), and is normally continuously supplied to the C terminal from the energization command signal. Now, when the ECU 3 applies the low level potential signal of the power generation voltage switching command signal to the C terminal, the voltage switching circuit 5 responds to the input of this low level potential signal by a predetermined reference voltage (for example, the internal power supply line HL = 13). (Comparative voltage equivalent to 0.5 V) is supplied to the comparator 17
As a result, the comparator 17 reduces the power generation until the internal power supply line HL becomes 13.5 V, and then the comparator 17 performs the duty ratio control so that the rectified generated voltage becomes this level.

FIG. 3 shows the energization command signal, and FIG. 4 shows the generated voltage switching command signal. Both signals discriminate two kinds of voltage states with one threshold value. Therefore, the voltage margin can be increased. In this embodiment, the voltage switching circuit 5 outputs a reference voltage Vrefh when a high level is output from a comparator (not shown) having a threshold value of Vth, and the comparator outputs a low level. Is output, the reference voltage generating circuit outputs a reference voltage Vrefl. However, since such a circuit design itself is well known, its description is omitted.

The power generation is stopped by turning off the ignition switch 4 and stopping the engine by the ECU 3. Further, when the power generation is stopped, the comparator 10 is turned off, and since the ECU 3 inputs a low level potential to the C terminal by turning off the ignition switch 4, the comparator 11 is also turned off, the transistors 8 and 12 are turned off, and the excitation current Energization and current consumption of the regulator 1 stop. (Embodiment 2) FIG. 5 shows another embodiment.

In this embodiment, the power generation voltage switching command signal during power generation has three levels, and accordingly the voltage switching circuit 5
Is also provided with two comparators and three types of potential V
H, VM, and VL are discriminated. And the voltage switching circuit 5
Instruct the potential VH to generate power at a level higher than the normal generation voltage, instruct the potential VM to generate power at the normal generation voltage level, and lower the potential VL to lower than the normal generation voltage. Command generation at the generation voltage level.

In this way, it is possible to perform power generation at three types of power generation voltage levels with the same voltage margin as in the conventional case (see FIG. 6). Further, the energization command signal at the time of power generation stop is set to three levels, the energization of the exciting current is stopped when the command signal is VL, the amount of the exciting current is energized at a low level in VM, and the larger exciting current is energized in VH. As a result, the power generation start rotation speed of the generator 2 can be switched. (Embodiment 3) FIG. 2 shows another embodiment.

In this embodiment, a voltage substantially equal to the rectified generated voltage is supplied to the internal power supply line HL as the output voltage of the auxiliary rectifier (half bridge) 23. On the other hand, the power generation start command signal and the power generation voltage switching command signal are input from the ECU 3 through the alarm lamp 20 to the L terminal which constitutes the command signal input terminal in the present invention. The operation will be described below.

When the ignition switch 4 is turned on before the engine is started, the ECU 3 outputs a high level potential signal (energization command signal) to the L terminal. Then, power is supplied to the internal power supply line HL from the L terminal through the diode D2, and the internal power supply line HL is connected to the Darling transistor 6
The base is supplied with electric power, an exciting current is supplied to the exciting coil 21, and power generation is started with engine operation. When power generation is started, the internal power supply line HL is supplied with the rectified generated voltage from the generator 2.

When the potential of the internal power supply line HL rises after the start of power generation, the potential applied from the resistor r6 to the cathode of the Zener diode ZD rises, which turns on the Zener diode ZD and turns on the transistor 22 and the transistor 22. 6 is turned off, and the exciting current is stopped. In this way, the generated voltage is controlled so that the internal power supply line HL becomes a predetermined level.

Next, the case where the generated voltage switching command signal is input will be described. During power generation, when a low level potential is output from the ECU 3 to the L terminal as a power generation voltage switching command signal, the transistor 21 is turned off, which changes the cathode potential of the Zener diode ZD to the high level side. The transistor 22 is turned on even when the internal power supply line HL has a relatively low potential.

As a result, the average generated voltage drops. After all, this embodiment can also achieve the same effects as the first embodiment. In this embodiment, the transistors 6 and 22 and the Zener diode ZD constitute the voltage control section in the present invention, and the transistor 21 and the diode 2 are included.
Composes a command control unit, that is, a power generation switching command unit and an energization command unit, and the auxiliary rectifier composes a power generation detection unit in the present invention. (Embodiment 4) FIG. 7 shows another embodiment.

In this embodiment, the comparators 10 and 11 are omitted from the first embodiment (FIG. 1). Even if the comparators 10 and 11 are omitted by adjusting the threshold voltage of the first-stage transistor inside the OR circuit or by providing a voltage dividing circuit on the input side of the OR circuit, the operation and effect are the same as those of the first embodiment. Becomes (Embodiment 5) FIG. 8 shows another embodiment.

In this embodiment, the voltage switching circuit 5 in the first embodiment (FIG. 1) is composed of voltage dividing circuits r31 and r32 and a Zener diode ZD. The Zener diode ZD can be omitted. With this configuration, the power generation voltage switching command signal input from the ECU 3 to the C terminal can be directly input to the comparator 17.

Therefore, in this case, the ECU 3 inputs the normal reference voltage Va or the reference voltage lower than the normal reference voltage Va to the negative input terminal of the comparator 17 through this voltage dividing circuit. In this case, the ECU 3 uses the voltage switching circuit 5
Input the analog voltage as a power generation voltage switching command signal to
As a result, it is possible to generate power at a desired voltage level.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a first embodiment.

FIG. 2 is a circuit diagram showing a third embodiment.

FIG. 3 is a timing chart showing the levels of energization command signals in the first embodiment.

FIG. 4 is a timing chart showing the level of a generated voltage switching command signal in the first embodiment.

FIG. 5 is a timing chart showing the level of a power generation voltage switching command signal in the second embodiment.

FIG. 6 is a timing chart showing the level of a command signal in a conventional regulator.

FIG. 7 is a circuit diagram showing a fourth embodiment.

FIG. 8 is a circuit diagram showing a fifth embodiment.

[Explanation of symbols]

5 is a voltage switching circuit (power generation voltage switching command unit, command control unit), 6 is a transistor (a part of the voltage control unit), 10 is a comparator (power generation detection unit, command control unit), 11 is a comparator (energization command unit, Command controller), 17 is a comparator (a part of the voltage controller), 18 is a transistor (a part of the voltage controller), C is an input terminal (command signal input terminal).

Claims (1)

[Claims] 1. A voltage controller for intermittently controlling an exciting current according to an output voltage of a generator to control the output voltage to a predetermined level, an energizing command signal for instructing energization of the exciting current, and the voltage controller. A command signal input terminal for inputting a control characteristic change command signal for instructing a change of the control characteristic of the control signal, and energization of the excitation current to the voltage control unit and the voltage control unit based on the both signals input from the command signal input terminal. In a voltage control device for a vehicle generator, which includes a command control unit that commands a change in control characteristics, the command control unit detects power generation, and a power generation detection unit that outputs a power generation detection signal; , The voltage control unit is instructed to energize the excitation current based on a power generation detection signal from the power generation detection unit, and in the case of power generation stop, the voltage based on the power supply command signal input to the command signal input terminal. An energization command unit that commands the control unit to energize the excitation current, and a control characteristic change that commands a change in the control characteristic of the voltage control unit based on the control characteristic change command signal input to the command signal input terminal during power generation. A voltage control device for a vehicle generator, comprising: a command unit.