JP2010235034A - Vehicular power supply control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular power supply control device reducing the power consumption by the load while avoiding degradation of the battery capacity. <P>SOLUTION: The vehicular power supply control device controls the conduction to a load 8 by the power discharged by a battery B to be charged by the power generated by a generator 1 and the power generated by the generator 1. The vehicular power supply control device comprises a charging current detector 6 for detecting the charging current value to the battery B, a storage means 4 storing the correspondence between the charging current value to the battery B and the conduction to the load 8, and a reading means (3) for reading the conduction corresponding to the charging current value detected by the charging current detector 6 from the correspondence stored in the storage means 4, and controls the conduction to the load 8 based on the conduction read by the reading means (3). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to the power discharged from the battery charged by the power generated by the generator and the energization of the load by the power generated by the generator, particularly to the heater system load such as a deicer or defogger. The present invention relates to a vehicle power supply control device that controls energization.

  In recent years, the number of electrical components mounted on a vehicle has been steadily increasing in terms of safety, convenience, comfort, and product power, and the power consumption of the entire vehicle is increasing. On the other hand, demands for improving the fuel efficiency of vehicles are increasing due to soaring fuel prices and environmental measures. As one means for improving fuel efficiency, it is also effective to reduce the amount of power consumption that suppresses the amount of power generated by an alternator (vehicle generator, AC generator). Moreover, even when the capacity of the battery as the power source is reduced, it is naturally effective to reduce the power consumption as a countermeasure.

  Patent Document 1 describes the start of a large electrical load mounted on a vehicle, and when there is a possibility that insufficient power supply occurs due to exceeding the power generation capacity of the on-vehicle generator, a load that does not start the large electrical load. A control device is disclosed.

JP 2007-209106 A

  When reducing the amount of power consumption, it is one measure to cut off the power supply to the load, but there is a problem that the convenience for the user is reduced by cutting off the power supply. Therefore, it has been proposed to increase or decrease the energization amount by PWM control according to the output voltage value of the battery in the heater system load or the like. This is intended to reduce power consumption by setting the energization amount (duty ratio) small when the output voltage value of the battery is high. Further, when the output voltage value of the battery is low, the heater function is ensured by setting the energization amount large.

However, when the energization amount is PWM controlled in this way, it is effective to reduce the power consumption. However, when the battery capacity is low, the energization amount to the load is set to a large value to the battery. There is a problem of increasing the burden of.
The present invention has been made in view of the circumstances as described above, and an object of the present invention is to provide a vehicle power supply control device capable of reducing power consumption due to a load while avoiding a decrease in battery capacity. To do.

  According to a first aspect of the present invention, there is provided a vehicular power supply control device that controls the power discharged from a battery charged by the electric power generated by the generator and the energization of a load by the electric power generated by the generator. A charging current detector for detecting a charging current value for the battery; storage means for storing a correspondence relationship between a charging current value for the battery and an energization amount to the load; and a charging detected by the charging current detector And a reading means for reading the energization amount corresponding to the current value from the correspondence stored in the storage means, and configured to control the energization to the load based on the energization amount read by the reading means. It is characterized by that.

  In this vehicle power supply control device, the power discharged from the battery charged by the power generated by the generator and the energization of the load by the power generated by the generator are controlled. The charging current detector detects the charging current value to the battery, and the storage means stores the correspondence relationship between the charging current value to the battery and the energization amount to the load. The reading means reads the energization amount corresponding to the charging current value detected by the charging current detector from the correspondence stored by the storage means, and controls energization to the load based on the energization amount read by the reading means.

  The vehicular power supply control device according to the second aspect of the present invention further comprises determination means for determining whether or not the charging current value detected by the charging current detector is equal to or greater than a predetermined current value, wherein the determination means is equal to or greater than the predetermined current value. The reading means is configured to read the energization amount corresponding to the charging current value when it is determined that.

  In this vehicle power supply control device, when the determining means determines whether or not the charging current value detected by the charging current detector is greater than or equal to a predetermined current value, and the determining means determines that it is equal to or greater than the predetermined current value. The reading means reads the energization amount corresponding to the charging current value.

  The vehicle power supply control device according to a third aspect of the present invention further includes voltage detection means for detecting the output voltage value of the battery, and the voltage detection means detects when the determination means determines that the current value is not equal to or greater than a predetermined current value. The power supply to the load is controlled based on the output voltage value.

  In this vehicle power supply control device, the voltage detection means detects the output voltage value of the battery. When the determination means determines that the current value is not greater than or equal to the predetermined current value, energization to the load is controlled based on the output voltage value detected by the voltage detection means.

  According to the vehicle power supply control device of the present invention, it is possible to realize a vehicle power supply control device capable of reducing power consumption due to a load while avoiding a decrease in battery capacity.

It is a block diagram which shows the principal part structure of embodiment of the vehicle power supply control apparatus which concerns on this invention. It is a flowchart which shows the example of operation | movement of the vehicle power supply control apparatus shown in FIG. It is explanatory drawing which shows the example of the correspondence of the duty ratio (energization amount) at the time of carrying out PWM control of the charging current value to a battery, and the electric power to a deisa.

Hereinafter, the present invention will be described with reference to the drawings illustrating embodiments thereof.
FIG. 1 is a block diagram showing a main configuration of an embodiment of a vehicle power supply control device according to the present invention.
In this vehicular power supply control device, a control unit 3 having a microcomputer turns on / off energization to a deaiser 8 as a load by means of a semiconductor switching element 7.
The power supply of the deaiser 8 is supplied from a battery B mounted on the vehicle and an alternator (generator, alternator) 1 that charges the battery B.

The output voltage value of the battery B is detected by voltage detection means 9 built in the control unit 3. Further, the charge / discharge current value of the battery B is detected by a current detector (charge current detector) 6 and given to the control unit 3. The control unit 3 is also given ON / OFF signals of the ignition switch 2 and the switch SW of the deaiser 8. The control unit 3 includes a timer 5.
The memory (storage means) 4 built in the control unit 3 has a duty ratio (when the PWM control is performed by the semiconductor switching element 7 for the charging current value to the battery B and the power to the deaiser 8 as shown in FIG. The correspondence relationship of the energization amount is stored as a table. This correspondence relationship may be stored as a mathematical expression.

  The correspondence relationship between the charging current value to the battery B and the duty ratio of the power to the deaiser 8 is determined when the charging current value is equal to or greater than the predetermined current value I1. For example, from a predetermined current value I1 to a current value I2 (> I1), the duty ratio decreases from 100% as the current value increases. When the charging current value is equal to or greater than the current value I2, the duty ratio is constant. (For example, 50%).

When the charging current value is smaller than the predetermined current value I1, the duty ratio is calculated by, for example, (12 / V) ² × 100 (%) based on the output voltage value V of the battery B as in the conventional case.
Thereby, when the charging current value is large, that is, when the battery capacity is low, the heater function of the deaiser 8 can be used to some extent while charging the battery, and the power consumption by the deaiser 8 can be reduced. .

Hereinafter, an example of the operation of the heater control apparatus having the above configuration will be described with reference to the flowchart of FIG.
First, the controller 3 determines whether or not the ignition switch 2 is turned on (S1). If the ignition switch 2 is turned on, the controller 3 determines whether or not the switch SW of the deaiser 8 is turned on (S3). ).
If the switch SW of the deaiser 8 is turned on (S3), the controller 3 determines whether or not a duty ratio for PWM control of the semiconductor switching element 7 is set (S5). If the duty ratio is not set and the duty ratio is not stored, the charging current value detected by the current detector 6 is read (S7).

When the control unit 3 reads the charging current value (S7), the control unit 3 determines whether or not the read charging current value is equal to or greater than the predetermined current value I1 shown in FIG. 3 (S9). If the charging current value is not equal to or greater than the predetermined current value I1, the output voltage value V of the battery B detected by the voltage detecting means 9 is read (S11). Next, based on the read output voltage value V of the battery B, for example, the duty ratio is calculated and set by (12 / V) ² × 100 (%) (S13).
Next, the controller 3 starts energization to the deaiser 8 by performing PWM control of the semiconductor switching element 7 with the set duty ratio (S13), and causes the timer 5 to start measuring time (S17).

Next, the controller 3 determines whether or not the time counted by the timer 5 is equal to or longer than a preset energization time (S19). If the time is not equal to or greater than the preset energization time, the ignition switch 2 is determined. It is determined whether or not is turned on (S1).
If the time counted by the timer 5 is equal to or longer than the set energization time (S19), the controller 3 stops energization to the deaiser 8 by the semiconductor switching element 7 (S25) and resets the timer 5 ( S27). Next, it is determined whether or not the ignition switch 2 is turned on (S1).

If the read charging current value is equal to or greater than the predetermined current value I1 (S9), the control unit 3 refers to the table stored in the memory 4 and reads the duty ratio corresponding to the read charging current value. (S23). Next, PWM control of the semiconductor switching element 7 with the set duty ratio starts energization to the deaiser 8 (S15), and the timer 5 starts measuring time (S17).
If the duty ratio is set (S5), the controller 3 determines whether the time counted by the timer 5 is equal to or longer than the set energization time (S19).

If the ignition switch 2 is not turned on (S1) or if the switch SW of the deaiser 8 is not turned on (S3), the control unit 3 determines whether or not the deaiser 8 is energized ( S21). If the deaiser 8 is not energized, it is determined whether or not the ignition switch 2 is on (S1).
If the deaiser 8 is energized (S21), the controller 3 stops energizing the deaiser 8 (S25), resets the timer 5 (S27), and then determines whether or not the ignition switch 2 is turned on. Is determined (S1).

1 Alternator (generator, AC generator)
2 Ignition switch 3 Control unit (reading means, judging means)
4 Memory (memory means)
5 Timer 6 Current detector (Charge current detector)
7 Semiconductor switching element 8 Deisa (heater)
9 Voltage detection means B Battery SW switch

Claims (3)

In the vehicle power supply control device that controls the power discharged from the battery charged by the power generated by the generator and the energization of the load by the power generated by the generator,
A charging current detector for detecting a charging current value for the battery; storage means for storing a correspondence relationship between a charging current value for the battery and an energization amount to the load; and a charging current detected by the charging current detector And a reading means for reading the energization amount corresponding to the value from the correspondence stored in the storage means, and configured to control the energization to the load based on the energization amount read by the reading means. A power supply control device for a vehicle characterized by   The apparatus further comprises determining means for determining whether the charging current value detected by the charging current detector is equal to or greater than a predetermined current value, and when the determining means determines that the charge current value is equal to or greater than the predetermined current value, the reading means The vehicular power supply control device according to claim 1, configured to read an energization amount corresponding to the charging current value.   Voltage detection means for detecting the output voltage value of the battery is further provided, and when the determination means determines that it is not equal to or greater than a predetermined current value, the load is energized based on the output voltage value detected by the voltage detection means. The vehicle power supply control device according to claim 2, which is configured to be controlled.

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