JP2000050523A - Voltage controller for generator on vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a generator voltage controller for a vehicle which is incorporated in a generator, does not give any feeling uncomfortable to passengers on a vehicle, and can improve fuel consumption of an internal combustion engine. SOLUTION: From the discrimination signal generating circuit 10 of a voltage controller 5, a signal VCN1 which indicates whether or not the number of revolutions of a generator 1 is equal to or lower than prescribed and does not change frequently is supplied to a control voltage discriminating circuit 11. From a load detecting and discriminating circuit 12, another signal VCF which indicates whether or not the output current of the generator 1 is equal to or higher than prescribed is supplied to the discriminating circuit 11. The circuit 11 controls the power generating voltage of the generator 1 to 13.0 V, when the number of revolutions of the generator 1 is equal to or lower than prescribed, and at the same time, the output current of the generator 1 is equal to or lower than prescribed. When the number of revolutions of the generator 1 exceeds the prescribed value, the circuit 11 controls the power generating voltage to 14.4 V. Consequently, a voltage controller which can improve the fuel consumption of an internal combustion engine by leaving a margin in the output current of the generator 1, and at the same time, will not give sense of physical disorder from being given to passengers on a vehicle by suppressing the flickering or the like of the head lamps of the vehicle can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular generator voltage control device for controlling a generated voltage of a vehicular generator based on the number of rotations of the vehicle.

[0002]

2. Description of the Related Art A generator for a vehicle is driven by an internal combustion engine, generates electric power by rotation of the internal combustion engine, and supplies electric power to an electric vehicle mounted on the vehicle and an electric load of the vehicle. Such a generator is provided with a voltage control device so that a voltage preset to the electric load of the storage device or the vehicle is obtained at any rotational speed.

By the way, as described in Japanese Patent Application Laid-Open No. Sho 59-2222099, the fuel consumption is improved by changing the voltage generated by a generator according to the state of the vehicle. A command value of the generated voltage is given by the control device to detect, and the generated voltage of the generator changes.

[0004]

In the above-described conventional control device for detecting the state of a vehicle, the control device is installed outside the generator, and wiring is installed between the control device and the generator. The generated voltage command value is transmitted by wiring.

However, since the generated voltage command value from the control device is transmitted to the generator via the wiring, when the wiring is disconnected, the generated voltage command value cannot be commanded to the generator, and the fuel consumption cannot be reduced. Operation control for improvement cannot be performed.

In recent years, it has been desired to improve the fuel efficiency of the internal combustion engine. However, it has not been attempted to improve the fuel efficiency by improving the characteristics of the voltage control device of the vehicle generator.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a voltage generator for a vehicular generator which is mounted inside the generator and which can improve the fuel efficiency of the internal combustion engine without giving an uncomfortable feeling to a passenger.

[0008]

In order to achieve the above object, the present invention is configured as follows. (1) In a voltage control device for a vehicle generator driven by an internal combustion engine, the voltage control device is built in the generator and detects a rotation speed of the generator,
There is provided a means for changing a set value of the generated voltage based on a result of comparison with a preset rotation speed.

Since the voltage control device is built in the generator, the fuel efficiency improvement operation is stopped by disconnecting the command signal transmission wiring between the generator and the control device, which occurs when the control device is disposed outside the generator. Can be prevented.

Further, by configuring the set value of the generated voltage to change in accordance with the number of revolutions of the generator, a margin for the output current of the generator can be provided, and the fuel efficiency can be improved.

(2) Preferably, in the above (1),
The change time of the set value of the generated voltage is longer than the change time of the rotation speed of the generator.

If the change time of the set value of the generated voltage is longer than the change time of the rotation speed of the generator, the output fluctuation of the electric load due to the frequent change of the generated voltage can be suppressed, and the passenger can be prevented from feeling uncomfortable. .

(3) Preferably, in the above (1), when the output current of the generator is equal to or more than a predetermined current value, the load detection determination means for inhibiting the set value of the generated voltage from being changed is provided. Prepare.

When the output current of the generator is equal to or higher than the predetermined current value, by inhibiting the change of the set value of the generated voltage, the output fluctuation of the electric load can be suppressed, and the occupant can be prevented from feeling uncomfortable.

(4) Preferably, in the above (1), means is provided for alleviating the voltage change when the set value of the generated voltage changes.

When the set value of the generated voltage changes, if the voltage change is moderated, the output fluctuation of the electric load can be suppressed, and the occupant can be prevented from feeling uncomfortable.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic configuration diagram of a vehicular generator voltage control device according to an embodiment of the present invention.

In FIG. 1, a rotor of a generator 1 is rotated via a belt by an internal combustion engine (not shown) mounted on a vehicle, and the rotation causes an excitation coil 4 wound around the rotor to flow. The exciting current generates a magnetic field. Then, the generated magnetic field is transmitted to the stator, and electric power is generated in the stator winding 2 wound on the stator.

The stator winding 2 is composed of three phases 2a, 2b and 2c, and the output of each phase is transmitted through a full-wave rectifier 3 to an electric load such as a battery 15 or a headlamp mounted on the vehicle (see FIG. 1). (Not shown), power is supplied to these electric loads. The exciting current flowing through the exciting coil 4 is controlled by a switch circuit 14 provided in a voltage control device 5 built in the generator 1.
Are composed of transistors and MOS-FETs.

When the switch circuit 14 is not conducting,
The exciting current flowing through the exciting coil 4 flows through the flywheel diode 6. In the first place, the function of the generator 1 is to control the voltage so that the generated voltage becomes a predetermined value. Here, the voltage is detected at the S terminal, and the voltage VS detected at the S terminal is, for example, The switch circuit 14 is controlled by a signal output from the control signal generation circuit 13 so as to be 14.4 V.

Next, the configuration and operation of the voltage control device 5 will be described. A power supply circuit 7 of the voltage control device 5 is connected to the generator 1 via a terminal B, and generates an internal power supply Vcc in the power supply circuit 7. The condition for generating the internal power supply Vcc is determined by turning on an engine start switch (not shown). Further, an alarm function (not shown) for turning on a warning light for notifying the vehicle occupant of the abnormality of the generator 1 and the voltage control device 5 is provided.

Here, a circuit and operation for detecting rotation according to the present invention will be described. First, 3 of stator winding 2
One phase (2b) voltage of the phases (2a, 2b, 2c) is input to the rotation detection circuit 9 via the P terminal. The one-phase voltage input via the P terminal has a signal waveform like the P terminal voltage shown in FIG. 2, and the period changes according to the rotation speed. The upper limit of the P terminal voltage is higher than that of the B terminal voltage of the generator 1 by the full-wave rectifier 3.
And the lower limit is lower than 0 V by the forward voltage drop of the diode.

Therefore, assuming that the B terminal voltage is 14 V and the forward drop voltage is 1 V, the center value is 7 V, and this is used as the judgment value of the period of the P terminal voltage.
Waveform shaping for accurately detecting the number of rotations can be performed.

Here, FIG. 3 shows the internal configuration of the rotation speed detecting circuit 9, and its operation will be described with reference to the signal waveforms of FIG. The rotation speed detection circuit 9 has a comparator 9a. The positive input terminal of the comparator 9a is supplied with a P terminal voltage, and the negative input terminal is supplied with a reference voltage of 7V. The output terminal of the comparator 9a is connected to the output terminal of the rotation speed detection circuit 9 via the capacitor 9b, the resistor 9d, and the resistor 9g.

The connection midpoint between the capacitor 9b and the resistor 9d is grounded via the resistor 9c. The connection midpoint between the resistors 9d and 9g is grounded via the cathode and anode of the diode 9f. Further, the resistor 9d and the resistor 9
The midpoint of connection with g is connected to the internal voltage power supply Vcc via the anode and cathode of the diode 9e. Also,
A connection point between the resistor 9g and the output terminal of the rotation speed detection circuit 9 is grounded via a capacitor 9h.

When the P terminal voltage is input to the comparator 9a, the output signal A of the comparator 9a has a waveform as shown in FIG. And this output signal A
Is converted into a signal B as shown in FIG. 2 by a differentiating circuit constituted by the capacitor 9b and the resistor 9c.

Next, the signal B becomes a signal C having an upper limit of Vcc and a lower limit of GND via a resistor 9d and a diode bridge composed of diodes 9e and 9f having an upper limit of Vcc and a lower limit of GND. A signal NALT, which is an output signal of the rotation speed detection circuit, is provided through an integration circuit including 9g and a capacitor 9h.

Since the voltage of the signal NALT increases as the number of revolutions increases (the frequency of the P terminal voltage increases), it is possible to cope with various controls based on the relationship between the number of revolutions and the voltage of the signal NALT. It becomes possible.

Next, the operation of the determination signal generation circuit 10 based on the number of rotations based on the signal NALT will be described with reference to FIG. For example, the number of rotations of the generator 1 is 2000 [r / mi].
n], the signal NALT is set to the voltage NALT1, and the voltage NALT1 is compared with the generated signal NALT by the rotation speed detection circuit 9 to generate the signal VCN.
The signal VCN goes to the “H” level when the signal NALT is lower than the voltage NALT1, and goes to the “L” level when the signal NALT is higher than the voltage NALT1.

Here, the setting of the number of revolutions of the generator 1 will be described. For example, as described above, the output current of the generator 1 when the voltage generated by the generator 1 is 14.4 V and the battery 15 can be charged. When compared with the output current of the generator 1 at a voltage (for example, 13.0 V), it has a characteristic that the maximum output current is turned over at a certain rotation speed. In other words, if the rotation speed is equal to or lower than a certain rotation speed, the output current of the generator 1 at 13.0 V becomes larger than the output current of the generator 1 at 14.4 V, but when the rotation speed exceeds a certain rotation speed, The output current of the generator 1 at 14.4V is larger than the output current of the generator 1 at 13.0V. The rotation speed at this time is 2000
[R / min].

In a vehicle, the rotational speed of the internal combustion engine vibrates and changes as shown by a signal NALT in FIG. 4 due to the influence of the transmission when the vehicle speed increases, such as during acceleration. In this state, signal VCN changes with a change in signal NALT, and has a pulse shape. If the pulse-shaped signal VCN is used as it is for the voltage control signal, the frequency of voltage change becomes too large, and the influence on the vehicle becomes large. In other words, when the vehicle is operating an electric load such as a headlamp or a car stereo, if the frequency of the voltage change is high, the illuminance and the sound change accordingly, giving the passenger an uncomfortable feeling.

Therefore, a control voltage determination signal VCN1 having a waveform as shown in FIG. 4 is generated from the signal VCN via an integration circuit (means for reducing a voltage change). The control voltage determination signal VCN1 has a voltage change frequency smaller than that of the signal VCN (the change time of the signal VCN1 is longer than the change time of the rotation speed of the generator 1). Can be smaller.

Here, the operation of the load detection determination circuit 12 will be described. FIG. 5 shows the voltage waveform of the F terminal, and the F terminal DUT which is the duty ratio of the F terminal voltage described below.
Y is the time when the F terminal voltage is in the high state, Toff, Lo.
When the time of the w state is Ton, it is represented by the following equation (1). F terminal DUTY = Toff ÷ (Ton + Toff) × 100 (1) FIG. 6 shows an F terminal DUTY of the generator 1 and a generator output whose voltage is controlled to a predetermined voltage by a general voltage control circuit. Regarding the relationship between currents (currents supplied to a battery and a vehicle load), characteristics are shown when the rotation speed of the generator 1 is used as a parameter.

The number of rotations of the generator 1 increases as the number of rotations becomes N1, N2, and N3. At this time, the F terminal DUTY at a certain current value IL1 is set to the number of rotations N1, N2,
DT1, DT2, and DT3 are obtained for each of N3.

From this characteristic, when the rotation speed of the generator 1 increases (the voltage of the signal NALT increases), the F terminal DUTY at the same output current also increases. Therefore, when performing control for changing the generated voltage of the generator 1 in the vehicle, a set value is provided for the output current of the generator 1, and when the output current is detected to be equal to or more than the set value, the control for changing the generated voltage is performed. Ban.

The above-mentioned set value of the output current is set to a level at which the electric load of the vehicle is ON, such as when the headlamp is turned on, and the illuminance and the operation sound are changed by the change in the generated voltage. By doing so, flickering or the like occurs, and the electric load that gives the passenger an uncomfortable feeling is set in consideration of the electric load.

Here, in the generator according to the present invention, the excitation flowing through the excitation coil 4 such that the voltage VS detected via the S terminal becomes a certain set voltage (for example, 14.4 V) as described above. The current is controlled by the switch circuit 14, and the operation will be described with reference to FIG.

FIG. 7 is an internal configuration diagram of the control voltage determination circuit 11. In FIG. 7, a voltage VS is supplied to a negative input terminal of a deviation amplifier 11e via a resistor 11a and a resistor 11c. The connection midpoint between the resistors 11a and 11c is grounded via the resistor 11b. Also, the deviation amplifier 11e
Is connected to a deviation amplifier 11 via a resistor 11d.
e is connected to the output terminal.

Reference voltage Vref from reference power supply circuit 8
Is supplied to the positive input terminal of the deviation amplifier 11e via the resistor 11f of the control voltage determination circuit 11. The positive input terminal of the deviation amplifier 11e is grounded via the capacitor 11i. Further, a positive input terminal of the deviation amplifier 11e is grounded via a resistor 11g and a switch 11h.

Output signal VC from load detection determination circuit 12
F and an output signal VCN1 from the determination signal generation circuit 10.
Is supplied to the input terminal of the AND circuit 11j. Then, the output signal of the AND circuit 11j switches the switch 11
The on / off of h is controlled.

First, the voltage VS detected via the S terminal
Becomes, for example, 1/4 of the voltage VS depending on the resistance ratio of the resistors 11a and 11b, and is input to the negative input terminal of the deviation amplifier 11e via the resistor 11c.

The control voltage Vr is applied to the reference power supply circuit 8 from the internal power supply Vcc generated by the power supply circuit 7.
ef (for example, assuming that the voltage controlled by the generator 1 is 14.4 V, a voltage of １ ／ of 14.4 V) is generated, and the control voltage Vref is applied to the positive terminal of the deviation amplifier 11 e via the resistor 11 f. Input to the input terminal. At this time, the difference between the control voltage Vref input to the positive input terminal and the voltage input to the negative input terminal is amplified by an amplification factor determined by the ratio of the resistors 11c and 11d, and the output voltage VC of the amplifier 11e is determined.

Here, as described above, the operation when the control voltage of the generator 1 is changed will be described. The rotation speed of the generator 1 is 2,000 [r / min].
And a signal VCF which becomes High when the output current is within a certain set value.
Are High, the output of the AND circuit 11j is H
The switch 11h that is turned on by being high plays a role of switching between conduction and non-conduction between the resistor 11g and GND.

For example, if the switch 11h is turned on, the control voltage Vref is divided by the resistors 11f and 11g, and the generated voltage of the generator 1 is determined. However, since the divided voltage is in a state where the capacitor 11i is charged, the voltage gradually decreases to a divided voltage value. In this state, the generated voltage of the generator 1 gradually decreases from the generated voltage determined by the control voltage Vref to the generated voltage determined by the divided voltage.
As a result, changes in the illuminance of the electric load and the operation sound in the vehicle are moderated.

When the switch 11h shifts from the conductive state to the non-conductive state, the voltage increases from the divided voltage to the control voltage Vref, but gradually increases due to the capacitor 11i. As a result, similarly to the transition from the non-conducting state to the conducting state, changes in the illuminance and the operation sound of the electric load in the vehicle become gentle.

The control voltage determination circuit 11 described above
The determined signal VC is input to the control signal generation circuit 13, and a signal for operating the switch circuit 14 is generated.

The results described above will be described with reference to FIG. 8. Explaining the conventional output characteristics (for example, a generated voltage of 14.4)
V) and output characteristics at the time of voltage drop (for example, the generated voltage 13.
0V) has the characteristics as shown in the figure. When the rotation speed of the generator 1 is 2000 [r / min] or less, the output current when the power generation voltage is 13.0 V and the output current when the power generation voltage is 14.4 V Output current, and the number of revolutions of the generator 1 becomes 20
If it exceeds 00 [r / min], the generated voltage 14.
The output current at 4V is larger than the output current at 13.0V of the generated voltage.

In the present invention, when the voltage is 2000 [r / min] or less, the output characteristics at the time of the voltage drop are obtained, and the output characteristic becomes 2000 [r / mi].
n], conventional output characteristics are obtained.

This allows the output current to have a margin,
That is, the output current of the generator can be made larger than before (at a rotation speed of 2000 [r / min] or less), and the generator can be controlled, thereby contributing to improved fuel efficiency.

As described above, by alleviating the response at the time of a rapid change in the rotational speed and setting the prohibited load on the vehicle, it is possible to improve the fuel efficiency without giving the passenger an uncomfortable feeling. It becomes possible.

In addition, since the voltage control device is built in the generator, the fuel efficiency improving operation that occurs when the control device is disposed outside the generator and that is caused by cutting the command signal transmission wiring between the generator and the control device is performed. Can be prevented from stopping.

That is, according to one embodiment of the present invention, there is provided a voltage control device for a vehicle generator which is mounted inside the generator and which can improve the fuel efficiency of the internal combustion engine without giving a feeling of discomfort to the occupant. Can be realized.

[0053]

Since the present invention is configured as described above, it has the following effects. Mounted inside the generator, it can prevent the fuel efficiency improvement operation from being stopped by cutting the command signal transmission wiring between the generator and the control device, and does not give the occupant a sense of discomfort, improving the fuel efficiency of the internal combustion engine It is possible to realize a voltage control device of a vehicular generator capable of performing the above.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a voltage control device for a vehicle generator according to an embodiment of the present invention.

FIG. 2 is a signal waveform diagram illustrating an operation of a rotation speed detection circuit.

FIG. 3 is an internal configuration diagram of a rotation speed detection circuit.

FIG. 4 is an operation explanatory diagram of a determination signal generation circuit.

FIG. 5 is a voltage waveform diagram of an F terminal.

FIG. 6 is a relationship diagram between an F terminal DUTY and a generator output current.

FIG. 7 is an internal configuration diagram of a control voltage determination circuit.

FIG. 8 is a diagram showing output current characteristics of a generator according to an embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 generator 2 stator winding 3 full-wave rectifier 4 excitation coil 5 voltage controller 7 power supply circuit 8 reference power supply circuit 9 rotation detection circuit 10 control determination signal generation circuit 11 control voltage determination circuit 12 load detection determination circuit 13 control signal generation Circuit 14 Switch circuit 15 Battery

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Sakae Hikida 2477 Takaba, Hitachinaka-shi, Ibaraki Prefecture Inside Hitachi Car Engineering Co., Ltd. (72) Susumu Sasaki Inventor Hitachi, Ltd. 2520, Oaza Takaba, Hitachinaka-shi, Ibaraki Prefecture Within the Automotive Equipment Division (72) Inventor Ippei Kobayashi 2nd Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa F-term (reference) 3G093 AA16 BA19 DB01 DB20 EB09 FA11 FB05 5G060 AA04 CA02 CA04 CA06 CA08 DA01 DB01 5H590 AA02 AA30 CA07 CA23 CB10 CC01 CC18 CC24 CC28 CD01 CE05 CE08 DD25 DD64 EB02 EB12 EB21 EB29 FA06 FB01 FB03 FC12 FC14 FC21 FC22 FC26 GA02 GB02 HA02 HA04 HA27 HB06 JA08 JA13 JA14 JB06 KK02

Claims (4)

[Claims] 1. A voltage control device for a vehicular generator driven by an internal combustion engine, wherein the voltage control device is built in the generator, detects a rotation speed of the generator, and is set in advance. A voltage control device for a vehicle generator, comprising: means for changing a set value of a generated voltage based on a result obtained by comparing the rotation speed with a set rotation speed. 2. The vehicular generator according to claim 1, wherein the change time of the set value of the generated voltage is longer than the change time of the rotation speed of the generator. Voltage control device. 3. The vehicle generator according to claim 1, further comprising a load detection / judgment means for prohibiting a change in a set value of a generated voltage when an output current of the generator is equal to or more than a predetermined current value. A voltage control device for a vehicular generator. 4. A voltage generator for a vehicle generator according to claim 1, further comprising means for reducing a change in the voltage when the set value of the generated voltage changes.