JPH01214235A - Recharge controller for vehicle - Google Patents

Abstract

PURPOSE:To recharge a vehicle mounted battery well even when power is fed to a high voltage load, by reducing the output from an AC generator through a voltage reducing means and feeding the reduced output to the battery. CONSTITUTION:Primary winding 9a of a transformer 9 is connected with the stator winding, while the secondary winding 9b is connected through a rectifier 10 with a battery 1. Winding ratio is set such that 14.5V voltage for recharging the battery 1 is produced in the secondary winding 9b upon application of 70V voltage onto the primary winding 9a. Consequently, the battery 1 can be recharged with 14.5V voltage with 70V voltage being applied onto a resistor 11 in a front glass.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vehicle charging device, and particularly to a vehicle charging device, which allows a high voltage load that operates at a higher voltage than the battery voltage to operate well, and which simultaneously charges the battery. The present invention relates to a vehicle charging control device that can be operated satisfactorily.

[Conventional technology]

BACKGROUND ART In recent years, an electrical circuit diagram as shown in FIG. 8 has been considered as a method for quickly melting ice on a frozen windshield or a frozen rear window.

This includes an electrical conductor inserted into the windshield,
Using a resistor such as a hot wire embedded in the rear glass, current is passed through these conductors and resistors to heat the glass.

Conventionally, when operating such a high voltage load, the eighth
As shown in the figure, a changeover switch 7o is provided in the charger connecting the charging generator 2 and the vehicle-mounted battery 1, and the output voltage of the charging generator 2 is switched and applied to a higher voltage load 11 than the vehicle-mounted battery 1.

At this time, a high voltage of about 70 (V) is generated in the charging generator and applied to the high voltage load.

Note that 6 in the figure is a voltage adjustment circuit that feeds back the battery voltage via the key switch 60. Under normal conditions, the circuit 6 controls the power generation of the charging generator 2 to maintain the battery voltage at a predetermined level when charging the battery. is maintained at a regulated voltage of

[Problem to be solved by the invention]

By the way, with the conventional device described above, when current is passed through a high voltage load (to melt ice on the front window or rear window), it is usually when the car is started, and the battery voltage has dropped and the high Since the vehicle battery is not charged while the voltage load is energized, problems such as battery over-discharge may occur.

SUMMARY OF THE INVENTION An object of the present invention is to provide a vehicle charging device that can charge an on-vehicle battery satisfactorily even while power is being applied to a high voltage load.

[Means to solve the problem]

In order to achieve the above object, the charging device of the present invention includes a stator winding (3), an excitation winding (4), and a full-wave rectifier (5) that performs full-wave rectification of the AC output of the stator winding. a battery (1) charged by the output of a full-wave rectifier of the alternator; a switch means (7) connected in series with the excitation winding; a high voltage load (11) operating at a high voltage; a switching means for switching the connection between the full wave rectifier and the battery or the connection between the full wave rectifier and the high voltage load; means turns the switch means ON and OFF to control the output of the full-wave rectifier to a first set voltage when the full-wave rectifier and the battery are connected.
a first control device that performs F control, and the switching means sets the output of the full-wave rectifier to a second setting higher than the first setting voltage when the full-wave rectifier is connected to the high-voltage load; a second control device that controls ON/OFF of the switch means to control the voltage, and a voltage for charging the battery by reducing the output of the stator winding to approximately the first set voltage; A charging control device for a vehicle is provided, comprising: a reducing means;

[Effect]

The switching means connects the full-wave rectifier of the alternator to the high-voltage load, increases the output of the alternator to a second set voltage, and applies a high voltage to the high-voltage load. can.

Furthermore, the battery voltage can be maintained at a predetermined adjusted value by reducing the output of the alternator to approximately the first set voltage by the voltage reducing means and supplying the output to the battery.

〔Example〕

The present invention will be described below with reference to embodiments shown in the drawings.

1 and 2 show a first embodiment of the charging control device of the present invention.

1 is a battery, 2 is a vehicle alternator, and 3 is a stator winding of the three-phase alternator 2. 4 is an excitation winding of the AC generator 2; 5 is a three-phase full-wave rectifier that rectifies the AC output of the stator winding 3; 6 is a regulator that controls the output voltage of the generator to a set value; It has an output transistor 7 and a voltage detection circuit 8 that control the flowing current. 9 is a transformer, 9a is a primary winding connected to the stator winding 3, 9b is a secondary winding, 10 rectifies the output of the secondary winding 9b of the transformer 9, and is connected to the battery 1. A rectifier, 11 is a transparent resistor vapor-deposited on the windshield that serves as a high voltage load, 12 is a first selector switch for determining whether or not to energize the resistor 11, and 13 is linked to an energization instruction switch and also a voltage detection switch. A second selector switch 14 for switching the voltage within the circuit 8 is a flywheel diode connected across the excitation winding 4 . 15 is connected to the battery via a switch 15a. For example, an electric load such as a headlight that is driven by the voltage of battery 1, diode 5
0 is a diode through which excitation current flows from the battery 1 when the generator is not generating power.

Further, as shown in FIG. 2, the voltage detection circuit 8 includes a transistor 60. whose collector is connected to the base of the output transistor 7. A Zener diode 61 whose anode side is connected to the base of this transistor 60. Diodes 62 and 63. It consists of resistors 64, 65, 66 and 67.

The first contact 13a of the changeover switch 13 is connected to a resistor 66 via a diode 63, while the first contact 13a of the changeover switch 13
The second contact 13b of the resistor 65 and the diode 62
are connected to the resistors 66 through the respective resistors 66.

In the above configuration, the operation thereof will be explained. When the engine E shown in FIG. 3 is started, the alternating current generator 2 also starts generating electricity. Normally, the first changeover switch 12 is connected to the first contact 12a side (battery 1);
The second changeover switch 13 is also connected to the first contact (first voltage detection terminal) 13a side.

Therefore, the voltage applied to the first voltage detection terminal 13a is applied to the resistor 6 via the diode 63 in the voltage detection circuit 8.
The voltage is divided between 6 and 67 and applied to the Zener diode 61. Here, the resistors 66 and 67 and the Zener diode 61 are set so that the transistor 60 becomes conductive when the voltage of the battery 1 is the first set voltage of 14.5 (V).

In the normal state, the voltage of the battery 1 is 14.5 (
By controlling the current flowing through the excitation winding 4, the current flowing through the excitation winding 4 is controlled depending on whether or not it is above 14.5 (V).
).

Next, consider a situation in which ice has adhered to the windshield in a cold region. At this time, the energization instruction switch 70 is turned on in order to supply current to the resistor 11 in the windshield.

Then, when the energization instruction switch 70 is turned on, the capacitor 87. A base current flows through the transistor 82 through the path of the resistor 91, and the transistor 82 continues to be turned on for a first predetermined period of time.

Therefore, when the transistor 82 is turned on, the base current of the eight-channel transistor 7 is cut off, and the excitation current flowing to the excitation winding 4 is cut off.

On the other hand, the output of the comparator 83 becomes 1 after a second predetermined time delay formed by the resistor 94 and the capacitor 88.

As a result, the excitation coils 12c of the switches 12 and 13,
13c are energized and set to the second setting 12b, 13, respectively.
It is thrown into the b side. Here, by setting the second predetermined time shorter than the first predetermined time, the first and second changeover switches 12 and 1
3 first settings 12a, 13a to second settings 12b,
It is possible to switch to the 13b side. Therefore, the first. Second
When the changeover switches 12 and 13 are switched, it is possible to prevent arcs from occurring between the contacts, thereby improving the life of the contacts.

By switching the second switch 13, the voltage applied to the second voltage detection terminal 13b is changed to the resistance 65. Since the voltage is applied to the voltage dividing circuit of resistors 66 and 67 via the diode 62, the Zener diode 61 becomes conductive unless a higher voltage is applied than when a voltage is applied to the first voltage detection terminal 13a. Therefore, transistor 60 cannot be turned on.

A full-wave rectifier 5 is connected to the second voltage detection terminal 13b.
The output of the resistor 65.66.67 will be applied.
The Zener diode 7 is set to conduct when a voltage of 70 (V), which is the second set voltage, is applied to the second voltage detection terminal 13b by the divided voltage. Therefore, the output transistor 7 is turned ON so that the output of the full-wave rectifier 5 is controlled to TO(V:l), and 0FFf15I
I control J.

As a result, 70 (V) is supplied to the resistor 11 via the second setting 12b of the first changeover switch 12. Due to this high voltage of 70 (V), the resistor 11 has a voltage of about 150 (V).
With an output of 0 (W), it is possible to quickly melt ice on the surface of a windshield in 2 to 3 minutes. Also, this 70 (V) was determined taking into consideration the resistance of resistor 11.

On the other hand, when the energization instruction switch 70 is turned on, the alternator generates a high output, so the alternator becomes a load on the engine, so as shown in FIG. is detected, and this detection signal is input to the control device 16 that controls the idle speed of the engine E.

The control device 16 controls the idle speed of the engine E from 600 (rpm) to 1500 Crpm.
), it has been rising. Normally, an alternator generates electricity by increasing the rotation speed to approximately twice the speed using a pulley.

Furthermore, when melting ice adhering to the windshield, the vehicle is normally in an idling state with the engine starting, so the on-vehicle battery is in a discharged state at this time.

Therefore, in the present invention, one part of the transformer 9 is added to the stator winding.
The secondary winding 9-a is connected, and the secondary winding 9b is connected to the battery 1 via a rectifier 10. In this transformer 9, when 70 (V) is applied to the primary winding 1a9a, the voltage (14 V) for charging the battery 1 is applied to the secondary winding 9b.
, 5 (V)) is generated.

Therefore, while applying a voltage of 70 (V) to the resistor 11,
It becomes possible to charge the battery at a voltage of 14.5 (V), and discharge of the battery 1 can be prevented.

Next, the ice attached to the windshield melts and resistor 1
i to 1! When the current is no longer needed and the energization instruction switch 70 is turned off, the potential at the connection point between the resistor 9o and the resistor 93 decreases, and the transistor 81 is turned on. This causes the capacitor 86. The base current of the transistor 82 flows through the resistor 89 for a third predetermined time period, and the transistor 82 is turned on.
The excitation current is cut off during this period. On the other hand, the output of the comparator 83 becomes 0 after a delay of the fourth predetermined time when the capacitor 8 is discharged, and the excitation coils 12c and 13c are deenergized.

Here, since the fourth predetermined time is shorter than the third predetermined time, when the switches 12 and 13 are switched, the current continues to cut off the excitation of the generator.

Here, the excitation coils 12c and 13c are energized and deenergized after the excitation current of the generator is cut off (after the transistor 7 is turned off).
The reason why the timing is delayed for a predetermined period of time is to prevent switching of the switch within this period, since even if the transistor 7 is turned off, the excitation current continues to flow through the diode 14 for a predetermined period of time.

And the first. The second changeover switch 12.13
When the contacts 12a and 13a are switched to the contacts 12a and 13a of
The output transistor 7 is controlled intermittently so that the voltage becomes 4.5 (V).

The circuit 100 in FIG. 2 is configured to automatically operate the energization instruction switch 70 using a thermistor 103. 101 is a comparator, lO2 is a resistor, and 103 is a thermistor that detects the temperature of glass, for example. When the temperature is low, the resistance value is high, and as a result, the output of the comparator 101 is 1, and the energization instruction switch 7'0 power is applied. It does the same thing as turning it on. When the resistor 11 is energized and the temperature of the glass rises, the resistance value of the thermistor 103 decreases and the comparator 101
The output of becomes O. In other words, the instruction to energize the resistor 11 can be automatically controlled by detecting the temperature of the windshield, etc., as described above.

Next, when supplying high voltage to the resistor 11, the output voltage of the generator is increased to supply the high voltage to the resistor 11, while the high voltage is reduced to the battery 1 by the transformer 9. Explain the benefits of things.

First, for example, compared to a transformer for boosting the voltage from 14.5 (V) to 70 V (which requires approximately 1500 (W) of power), the voltage of 70 (V) in the present invention can be increased to 14.5 (V). )
The transformer 9 can be reduced in power to about 100 (W), and the transformer can also be significantly miniaturized.

Second, during the period when the generator is generating electricity at 14.5 V,
The voltage applied to the primary winding 9a of the transformer 9 is also 1'4
．． 5 (V), which is sufficiently lower than when high voltage is generated, so the excitation current loss of the transformer 9 can be almost ignored.

Thirdly, explanation will be made based on FIG. 4. This figure 4 is a characteristic diagram of the output voltage with respect to the generator voltage, and it is clear from this that as the rotation speed of the alternator increases, the generator voltage at the peak value of the output power increases. .

Therefore, when generating high output from the alternator, the engine's idle speed is increased to 1,500 (rps), and the alternator's rotation speed is reduced to approximately 3,000 (rpm).
Then, from Figure 4, the generator is 3000 (rp
It was found that during the rotation of m), the output voltage of the generator was 70 (V), and the output power almost reached its peak value. In other words,
By setting the output voltage of the generator to 70 (V), the maximum output power can be supplied to the resistor 11.

Therefore, with respect to the rotational speed of the alternator when idling up, the output voltage when the output power is at its peak at that rotational speed is equal to the voltage applied to the resistor 11, so that the generator is Maximize the output power of 'resistor 1
1 can be effectively supplied.

FIG. 5 shows a second embodiment, in which 20 is a known DC-
In the DC converter, 20a is an input terminal, 2ob is an output terminal, and 20C is a common terminal.

In the above configuration, when 70V is applied to the resistor 11, the DC-DC converter 20 outputs 14.V to the output terminal 20b.
5 V is generated to charge the battery 1.

In the DC-DC converter system shown in Figure 5, recent advances in semiconductor technology have made it possible to operate at several hundred kilohertz.As a result, the transformer used in the DC-DC converter can be made much smaller and lighter. can be converted into Furthermore, according to this system, the generator structure can be used without any changes from conventional generators.

FIG. 6 shows a DC-DC converter shown in FIG. 5 using a chopper, and 30 is a transistor.

31 is a control circuit, 32 is a reactor, and 33 is a diode.

In FIG. 6, when transistor 30 is turned on, charging current flows to the battery via reactor 32. Next, when transistor 30 turns off, reactor 32 connects battery 1. Current continues to flow through the diode 33 path. By controlling the repetition ratio (conduction ratio) of the transistor 300 being turned on and off by the control circuit 31, the current for charging the battery 1 can be set to an arbitrary value.

In FIG. 7, 40 is a full-wave rectifier that performs phase control using a thyristor, and 41 is a phase control circuit. In the figure, during the period when the generator 2 is generating high voltage, the full-wave rectifier 4
0 performs phase control to control the voltage applied to the battery 1 to be 14.5V.

During the period when the generator is generating 14.5 V, the current requirement of the rectifier 40 is sufficiently smaller than that of the rectifier 5, so the sirisk of the rectifier 40 is turned off and the operation is stopped.

In the embodiments shown in FIGS. 6 and 7, the resistance of the resistor 11 attached to the windshield varies widely depending on the vehicle model, etc., and it is very difficult to adjust the charging voltage to the battery accurately. It's easy.

Further, although it has been explained that the excitation winding of the generator is connected to the output terminal of the generator, it operates in the same way even if it is connected to the battery terminal. In this case, the diode 50 becomes unnecessary.

As described above, in the present invention, when multiple output voltages are required in cases where the mounting space for the generator is limited, such as in automobiles, the generator generates a high voltage and steps down the voltage. and supply it to low voltage loads? Since only one generator is required and the means necessary for voltage step-down is also small, there is no impact on the ease of mounting on a vehicle.

Furthermore, in the present invention, even when the generator generates electricity at high voltage, the output voltage is controlled by the regulator. Therefore, the accuracy of the output voltage is not so necessary; for example, the generator may be kept in a fully excited state and the output voltage may be varied by the generator rotation speed (engine rotation speed control).In this case, In this case, a DC-DC converter or a phase control method that can variably control the output voltage is excellent as a step-down means.

〔Effect of the invention〕

As described above, in the present invention, when driving a high-voltage load, the output voltage of the alternator is increased to the second set voltage, and the output voltage is reduced by the voltage reduction means. Since the battery is charged with a set voltage of 1, the battery can be charged satisfactorily even under a high voltage load, and the voltage reducing means can also be made smaller, which is an excellent effect.

The advantage is that output can be effectively extracted by increasing the rotation speed of the generator to a predetermined value and setting the voltage supplied to the high voltage load to the output voltage at the maximum output power at that rotation speed. It has a positive effect.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram showing the main parts of the first embodiment of the charging device of the present invention, FIG. 2 is an electric circuit diagram showing a part of the device in the first embodiment, and FIG. FIG. 4 is a characteristic diagram showing the relationship between the output voltage and the generator voltage, FIG. 5 is an electric circuit diagram showing the second embodiment of the charging device of the present invention, and FIG. 6 is a circuit diagram showing the entire device in this example. Third aspect of the charging device of the present invention
FIG. 7 is an electric circuit diagram showing a fourth embodiment of the charging device of the present invention, and FIG. 8 is an electric circuit diagram showing a conventional charging device. l... Battery, 2... Alternator, 3... Stator winding, 4... Excitation winding, 5... Full wave rectifier, 7
...Output transistor forming switch means, 8...
Voltage detection circuit, 11...Resistor forming a high voltage load, 1
2.13... 1st. second switching means, 9, 10, 20;
．． 40.41...Transformers and rectifiers that serve as voltage reduction means. DC-DC converter, thyristor, phase control circuit.

Claims (7)

[Claims] (1) The stator winding (3), the excitation winding (4), and a full-wave rectifier for full-wave rectifying the AC output of the stator winding (
5); a battery (1) charged by the output of the full-wave rectifier of the alternator; a switch means (7) connected in series with the excitation winding; and the battery voltage a high voltage load (11) that operates at a higher voltage than the switching means (12) for switching the connection between the full wave rectifier and the battery or the connection between the full wave rectifier and the high voltage load. When the full-wave rectifier and the battery are in a connected state, the switching means turns the switching means ON and OFF in order to control the output of the full-wave rectifier to the first set voltage.
a first control device that performs F control, and the switching means sets the output of the full-wave rectifier to a second setting higher than the first set voltage when the full-wave rectifier is connected to the high-voltage load; a second control device that controls ON/OFF of the switch means to control the voltage, and a voltage for charging the battery by reducing the output of the stator winding to approximately the first set voltage; A charging control device for a vehicle, comprising: a reducing means; (2) Vehicle charging control according to claim 1, wherein the switching means increases the rotation speed of the engine and increases the rotation speed of the alternator when the full-wave rectifier and the high voltage load are connected. Device. (3) The vehicle according to claim 2, wherein when the rotational speed of the alternator is increased, the output voltage of the alternator at the maximum value of the output power of the alternator and the second set voltage are made to substantially match. charging control device. (4) The vehicle charging control device according to claim 1, wherein the switching means turns off the switching means when switching the connection, and switches the connection after a predetermined period of time. (5) The voltage reduction means includes a reactor connected to the battery, a switch element connected between the high voltage load and the reactor, and a control device that controls ON/OFF of this element at a predetermined conduction ratio. Claim 1 consisting of a circuit.
Charging control device for the vehicle described. (6) Comprising an output winding (3) and an excitation winding (4),
A generator (2) driven by an engine (E), a battery (1), a high voltage load (11) that operates at a voltage higher than the voltage of the battery, an output winding of the generator and the battery. Alternatively, a switching means (12) for switching the connection with the high voltage load, and a switching means (7) for controlling the current flowing through the excitation winding.
), a first control device for controlling the voltage of the battery to a first predetermined voltage when the output winding and the battery are connected by the switching means; a rotation speed control device that increases the rotation speed of the engine to increase the rotation speed of the generator to a predetermined rotation speed when the output winding and the high voltage load are in a connected state; When connected to a high voltage load, the voltage applied to the high voltage load is controlled to the output voltage of the generator at approximately the maximum value of the output power of the generator at the predetermined rotation speed of the generator. A vehicle charging control device comprising: a second control device; (7) The vehicle charging control device according to any one of claims 1 to 6, wherein the high voltage load is a resistor provided on a windshield.