KR101499517B1 - Power control circuit and power control method - Google Patents

Abstract

The present invention relates to a power control circuit to control power supplied to a load from a battery. The power control circuit comprises: multiple switches; a charging unit which is charged by a battery voltage supplied from a battery; and a power control unit to control a load output voltage outputted to a load or power supply to the charging unit by controlling the switches, wherein the power control unit controls the switches to output the battery voltage as the load output voltage until the load output voltage reaches a predetermined first reference voltage and to control the switches to output, as the load output voltage, a first pumping voltage pumped by a charge voltage charged in the charging unit by charging the charging unit if the load output voltage reaches the first reference voltage, thereby securing safety of the load output voltage.

Description

[0001] POWER CONTROL CIRCUIT AND POWER CONTROL METHOD [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply control circuit and a power supply control method, and more particularly, to a power supply control circuit and a power supply control method, To a power supply control circuit and a power supply control method for preventing a battery of a vehicle from being excessively discharged to secure a starting power of a vehicle at an appropriate level or higher.

Due to the increasing value of vehicles, various types and specifications of electric vehicles have been installed in vehicles in recent years, and this trend is expected to accelerate further. As a result, the number of electric parts and the load consumed thereby increase the power consumption of the vehicle battery.

In addition, even when the vehicle is turned off, the number of electric components consuming the battery is increasing, so that the power consumption of the battery is doubled. Thus, when the vehicle is not started, the battery is continuously discharged, The voltage of the transistor is unstable. If the power supplied from the battery becomes unstable, the electric parts (for example, a vehicle black box, etc.) that should operate in a state in which the ignition is turned off do not receive a stable voltage and can not operate normally. There is a problem that the operation according to the purpose can not be performed.

Further, when the power consumption of the vehicle battery is further accelerated due to the power consumption by the electric components as described above in the state that the vehicle is not turned on, the vehicle battery is discharged excessively below a predetermined voltage level, There is a problem that the starting voltage required when starting the operation is not secured and the vehicle can not be used immediately.

The background art of the present invention is disclosed in Korean Patent Laid-Open Publication No. 2010-0072461 (published on Mar. 07, 2010).

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a method for preventing a voltage level of a power source supplied from a battery to a load of a vehicle from falling below a proper level, thereby securing stability of a load output voltage, A power supply control circuit and a power supply control method which are capable of ensuring startup power of a vehicle at an appropriate level or higher.

According to an aspect of the present invention, there is provided a power supply control circuit for controlling power supplied from a battery to a load, the power supply control circuit comprising: a plurality of switches; A charging unit charged by a battery voltage supplied from the battery; And a power supply controller for controlling a load output voltage output to the load or a power supply to the charger by controlling the plurality of switches, wherein the power supply controller controls the power supply controller so that the load output voltage reaches a first reference voltage The control unit controls the plurality of switches so as to output the battery voltage as the load output voltage before reaching the first reference voltage, and when the load output voltage reaches the first reference voltage, And controls the plurality of switches to output the pumped first pumping voltage as the load output voltage.

In the present invention, the power source control unit controls the plurality of switches to discharge the charging unit and output the first pumping voltage when the load output voltage reaches a second reference voltage lower than the first reference voltage .

In the present invention, the charging unit includes a first capacitor and a second capacitor connected in series.

In the present invention, the power source control unit charges the first and second capacitors when the load output voltage reaches the first reference voltage, and the load output voltage is applied to a second reference voltage lower than the first reference voltage And controls the plurality of switches to discharge the voltage charged in at least one of the first and second capacitors to output the first pumping voltage by the discharge voltage.

In the present invention, after the first pumping voltage output, the power source control unit charges the second capacitor again when the load output voltage reaches a third reference voltage, and when the load output voltage reaches the second reference voltage again And controls the plurality of switches so as to discharge the voltage charged in the second capacitor and output the second pumping voltage pumped by the discharge voltage as the load output voltage.

In the present invention, the first reference voltage and the third reference voltage are identical.

The present invention further includes a main switch for switching a power supply from the battery, and when the load output voltage reaches a fourth reference voltage lower than the second reference voltage, the power supply control unit turns off the main switch And the power supply to the load is cut off.

In the present invention, the plurality of switches may include: a first switch connected between the battery and one side of the first capacitor; A second switch connected between the battery and one side of the second capacitor; A third switch connected between the first capacitor and the second capacitor; A fourth switch connected between the battery and the other side of the first capacitor; A fifth switch connected between the first switch and the load; A sixth switch connected between the third switch and the load; And a seventh switch connected between the second switch and the ground.

In the present invention, the power control unit controls to turn on only the first and fifth switches to output the battery voltage as the load output voltage before the load output voltage reaches the first reference voltage, And when the voltage reaches the first reference voltage, only the first, third, fifth, and seventh switches are turned on to charge the first and second capacitors.

In the present invention, when the load output voltage reaches a second reference voltage lower than the first reference voltage during the charging of the first and second capacitors, the power supply control unit controls the second, fourth, fifth, 6 switches are turned on so that the first pumping voltage pumped by the charge voltage charged in the first and second capacitors is outputted as the load output voltage.

In the present invention, when the load output voltage reaches a second reference voltage lower than the first reference voltage during charging of the first and second capacitors, the power source control unit turns on only the fourth and fifth switches, The first capacitor is controlled to output a first pumping voltage that is pumped by the charge voltage charged in the first capacitor as the load output voltage or by turning on only the second and sixth switches, And to output the first pumping voltage as the load output voltage.

In the present invention, after the first pumping voltage output, the power source control unit charges the second capacitor again when the load output voltage reaches a third reference voltage, and when the load output voltage reaches the second reference voltage again And discharges a voltage charged in the second capacitor to output a second pumping voltage pumped by the discharge voltage as the load output voltage.

According to another aspect of the present invention, there is provided a battery charger that includes a charger that is charged with a battery voltage supplied from a battery, and a control unit that controls a plurality of switches to control a load output voltage output to the load or a power supply to the charger A power supply control method performed by a power supply control circuit including a power supply control unit, comprising: outputting the battery voltage as the load output voltage to the load when startup is off; Charging the charging unit when the load output voltage reaches a first reference voltage; And discharging the charged voltage charged in the charging unit when the load output voltage reaches a second reference voltage lower than the first reference voltage to output the pumped first pumping voltage as the load output voltage The power control method comprising:

In the present invention, the charging unit includes a first capacitor and a second capacitor connected in series.

In the present invention, in the step of controlling to output the first pumping voltage as the load output voltage, the first and second capacitors are charged when the load output voltage reaches the first reference voltage, Discharging a voltage charged in at least one of the first and second capacitors when the voltage reaches the second reference voltage, and outputting the first pumping voltage according to the discharge voltage.

The present invention further includes the steps of: controlling the first pumping voltage to be output as the load output voltage, and then recharging the second capacitor when the load output voltage reaches a third reference voltage; And discharging a voltage charged in the second capacitor when the load output voltage reaches the second reference voltage again to output a second pumping voltage pumped by the discharge voltage as the load output voltage .

In the present invention, the first reference voltage and the third reference voltage are identical.

According to the present invention, after the step of controlling to output the second pumping voltage as the load output voltage, when the load output voltage reaches a fourth reference voltage lower than the second reference voltage, the main switch is turned off, And the step of disconnecting the power supply to the power supply unit.

A power supply control circuit and a power supply control method according to the present invention are configured to pump a load voltage to a load when a voltage level of a power supply supplied from a battery to a load of the vehicle falls below a predetermined level so that the load output voltage can be stably supplied In addition, the battery of the vehicle is prevented from being excessively discharged, so that the start power of the vehicle can be ensured at an appropriate level or higher.

1 shows a configuration of a power supply control circuit according to an embodiment of the present invention.
2A to 2F are circuit configuration diagrams for explaining the operation of the power supply control circuit according to the present embodiment.
3 is a conceptual diagram showing a change in a load output voltage according to a change in battery voltage in the power supply control circuit according to the present embodiment.
4 is a flowchart for explaining the operation of the power supply control circuit according to the present embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.

FIG. 1 is a circuit diagram of a power supply control circuit according to an embodiment of the present invention. FIGS. 2A to 2F are circuit diagrams for explaining the operation of the power supply control circuit according to the present embodiment. FIG. 5 is a conceptual diagram illustrating a change in a load output voltage according to a change in battery voltage in the power supply control circuit according to the present embodiment.

1, the power supply control circuit 100 according to the present embodiment is a circuit for controlling the power supplied from the battery 200 to the load, and includes a plurality of switches S1 to S7; A charging unit 20 charged by the battery voltage VBAT supplied from the battery 200; And a power supply controller 10 for controlling the load output voltage Vout output to the load 300 or the power supply to the charger 20 by controlling the plurality of switches S1 to S7. The power control unit 10 receives the load output voltage Vout and controls ON / OFF of the plurality of switches S1 to S7.

The power control unit 10 controls the plurality of switches S1 to S4 so as to output the battery voltage VBAT as the load output voltage Vout before the load output voltage Vout reaches the predetermined first reference voltage Vref1, S7. At this time, when the load output voltage Vout reaches the first reference voltage Vref1, the power control unit 10 charges the charging unit 20 to charge the pumping voltage pumped by the charging voltage charged to the charging unit 20, And controls the plurality of switches S1 to S7 to output them as the output voltage Vout.

As shown in FIG. 1, the charging unit 20 includes a first capacitor C1 and a second capacitor C2 connected in series via a switch S3.

The plurality of switches S1 to S7 may include a first switch S1 connected between the battery 200 and one side of the first capacitor C1; A second switch S2 connected between the battery 200 and one side of the second capacitor C2; A third switch S3 connected between the first capacitor C1 and the second capacitor C2; A fourth switch S4 connected between the battery 200 and the other side of the first capacitor C2; A fifth switch S5 connected between the first switch S1 and the load 300; A sixth switch S6 connected between the third switch S3 and the load 300; And a seventh switch S7 connected between the second switch S2 and the ground.

1, the power supply control circuit 100 according to the present embodiment may further include a main switch SO for switching power supply from the battery 200, Also controls on / off of the main switch S0. The main switch S0 is a switch for controlling the entire power supplied from the battery 200 to the load 300. [ When the load output voltage Vout reaches the fourth reference voltage Vref4 which is lower than the second reference voltage Vref2, the power supply control unit 10 turns off the main switch SO and supplies power to the load 300 Thereby ensuring a minimum amount of starting power.

4 is a flowchart for explaining the operation of the power supply control circuit according to the present embodiment. Hereinafter, the operation of the power supply control circuit according to the present embodiment will be described in detail with reference to Figs. 2A to 2F, Figs. 3 and 4. Fig. For reference, the battery voltage VBAT in this embodiment means the output voltage of the battery whose voltage level changes when the battery is discharged by use.

The power supply control unit 10 continuously turns on the main switch S0 until the load output voltage Vout is reduced to reach a fourth reference voltage Vref4 for ensuring starting power Respectively. That is, in the following description, it is assumed that the power source control section 10 is turned on while the main switch SO is kept in the ON state until the load output voltage Vout is reduced to reach the fourth reference voltage Vref4, (S1 to S7) are controlled.

When the start of the vehicle is turned off (S401), the power control unit 10 first supplies power from the battery 200 to the load 300 (S402). That is, as shown in FIGS. 2A and 3, before the load output voltage Vout reaches the first reference voltage Vref1 after the startup is turned off, the power control unit 10 controls the first and fifth switches S1 and S5 and turns off the remaining switches S2 to S4 and S6 and S7 to control the battery voltage VBAT to be outputted as the load output voltage Vout. That is, since the battery voltage VBAT can still supply stable power to the load 300 immediately after the start of the vehicle is turned off, the battery voltage VBAT is output as the load output voltage Vout without performing another voltage pumping operation.

3, when the load output voltage Vout reaches the first reference voltage Vref1, the power supply control unit 10 outputs the first, third, fifth, 7 switches S1, S3, S5 and S7 are turned on and the other switches S2, S4 and S6 are turned off to charge the first and second capacitors C1 and C2. Which is a voltage for supplying a stable voltage to the load 300 and which is a voltage before the load output voltage Vout reaches the second reference voltage Vref2 which can be referred to as a threshold voltage for stable operation of the load, (Vref1), the first and second capacitors C1 and C2 are charged. Accordingly, the battery voltage VBAT is charged in the charger 20, and if the capacitances of the first and second capacitors C1 and C2 are the same, a voltage corresponding to 0.5VBAT is charged in each capacitor. Of course, since the power supply must be supplied to the load 300 at this time, the fifth switch S5 is continuously turned on so that stable power supply to the load 300 is performed even during charging.

The first reference voltage Vref1 is a voltage higher than the second reference voltage Vref2 and is a reference voltage for starting the charging of the charger 20, and the voltage value is a battery capacity, a load capacity, And the like.

Next, as shown in FIG. 3, it is determined whether the load output voltage Vout during charging of the charger 20 is lower than the first reference voltage Vref1 and reaches the second reference voltage Vref2 2C, the power supply controller 10 discharges the charging unit 20 to output the first pumping voltage to the plurality of switches S1 to S7, (S404).

That is, when the load output voltage Vout reaches the second reference voltage Vref2, which is a threshold voltage for stable operation of the load, the power supply control unit 10 outputs the second, And sixth switches S2, S4, S5 and S6 are turned on and the remaining switches S1, S3 and S7 are turned off so that the first and second capacitors C1 and C2, which are pumped by the charge voltage charged in the first and second capacitors C1 and C2, And controls the pumping voltage to be output as the load output voltage Vout.

Accordingly, when the capacitances of the first and second capacitors C1 and C2 are equal to each other, the first pumping voltage corresponding to 1.5VBAT (1.5 times the battery voltage) Is output as the load output voltage Vout so that the stable supply of voltage to the load 300 is achieved (see FIG. 3). Of course, depending on the embodiment, it is also possible to configure to generate only the first pumping voltage by discharging any one of the first and second capacitors C1 and C2 at this time.

3, when the load output voltage Vout falls again to reach the third reference voltage Vref3, the power supply control unit 10 outputs the first pumping voltage as shown in FIG. 2D Similarly, the third, fourth, and seventh switches S3, S4, and S7 are turned on to charge the second capacitor C2 again. Of course, since the power supply must be supplied to the load 300 also, the first and fifth switches S1 and S5 are continuously turned on so that stable power supply to the load 300 is performed even during charging. The second capacitor C2 is provided to supply a stable voltage to the load 300. When the third reference voltage Vref3 is a voltage before the load output voltage Vout reaches the second reference voltage Vref2, . Accordingly, the battery voltage VBAT is charged in the second capacitor C2 of the charging unit 20. [

The third reference voltage Vref3 is a reference voltage for resuming charging of the charger 20 as a voltage higher than the second reference voltage Vref2 and the voltage value is a battery capacity, And the like. The third reference voltage Vref3 may be equal to or different from the first reference voltage Vref1 as shown in FIG.

Next, it is determined whether the load output voltage Vout during charging of the second capacitor C2 of the charging unit 20 falls further than the third reference voltage Vref3 and reaches the second reference voltage Vref2 again (S405),

2E, when the load output voltage Vout reaches the second reference voltage Vref2, the power supply control unit 10 discharges the second capacitor C2 of the charging unit 20, The plurality of switches S1 to S7 are controlled so as to output the two pumping voltages (S406). That is, as shown in FIG. 3, when the load output voltage Vout reaches the second reference voltage Vref2 which is a threshold voltage for stable operation of the load, the power supply control unit 10 The second and sixth switches S2 and S6 are turned on and the remaining switches S1, S3, S4, S5 and S7 are turned off to set the second pumping voltage pumped by the charge voltage charged in the second capacitor C2 And outputs it as the load output voltage Vout. Accordingly, a second pumping voltage corresponding to 2VBAT (twice the battery voltage) is output as the load output voltage Vout by the charging voltage charged in the second capacitor C2, and a stable voltage (See Fig. 3).

After the second pumping voltage output, as shown in FIG. 3, whether the load output voltage Vout falls again reaches a fourth reference voltage Vref4 lower than the second reference voltage Vref2 (S407).

When the load output voltage Vout reaches the fourth reference voltage Vref4 as a result of the determination, the power supply control unit 10 turns off the main switch S0 and supplies power to the load 300 as shown in FIG. 2F (S408). This is for securing a minimum starting power source for starting, thereby preventing the battery voltage VBAT from becoming too low by discharging the battery completely.

As described above, in the power supply control circuit according to the present embodiment, when the voltage level of the power source supplied from the battery of the vehicle to the load falls below a certain level, the power source control circuit pumped it by the charging voltage, In addition, the battery of the vehicle is prevented from being excessively discharged, so that the starting power of the vehicle of an appropriate level or higher can be ensured.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, It belongs to the scope of right.

100: power supply control circuit
10: power supply control unit 20:
200: Battery 300: Load
S0: Main switch
S1 to S7: first to seventh switches

Claims (18)

A power supply control circuit for controlling power supplied from a battery to a load,
A plurality of switches;
A charging unit including a first capacitor and a second capacitor charged by the battery voltage supplied from the battery and connected in series; And
And a power supply controller for controlling the load output voltage output to the load or the power supply to the charger by controlling the plurality of switches,
The plurality of switches may include: a first switch connected between the battery and one side of the first capacitor; A second switch connected between the battery and one side of the second capacitor; A third switch connected between the first capacitor and the second capacitor; A fourth switch connected between the battery and the other side of the first capacitor; A fifth switch connected between the first switch and the load; A sixth switch connected between the other side of the second capacitor and the load; And a seventh switch connected between the second switch and ground,
The power control unit controls the first and fifth switches to output the battery voltage as the load output voltage before the load output voltage reaches a predetermined first reference voltage, And controls the first, third, fifth, and seventh switches to charge the first and second capacitors when the first reference voltage is reached.
The method according to claim 1,
Wherein the power supply control unit discharges the charging unit when the load output voltage falls and reaches a second reference voltage lower than the first reference voltage to generate a first pumping voltage generated by the battery voltage and a discharging voltage discharged from the charging unit, And outputs a voltage as the load output voltage.
delete The method according to claim 1,
The power control unit controls the second switch, the fourth switch, the fifth switch, and the sixth switch when the load output voltage falls and reaches a second reference voltage lower than the first reference voltage, 2 capacitors to discharge the charged voltage and to output the discharge voltage and a first pumping voltage generated by the battery voltage as the load output voltage.
5. The method of claim 4,
Wherein the power control unit controls the third switch, the fourth switch, and the seventh switch when the load output voltage falls and reaches a third reference voltage higher than the second reference voltage after the first pumping voltage is output, 2 capacitor is charged again and when the load output voltage falls again to reach the second reference voltage, the second switch and the sixth switch are controlled to discharge the voltage charged in the second capacitor, And outputs a second pumping voltage generated by the battery voltage as the load output voltage.
6. The method of claim 5,
Wherein the first reference voltage and the third reference voltage are the same.
The method according to any one of claims 2, 4, 5, and 6,
Further comprising a main switch for switching power supply from the battery,
And when the load output voltage reaches a fourth reference voltage lower than the second reference voltage, the power supply control unit turns off the main switch to cut off the power supply to the load.
delete delete delete The method according to claim 1,
When the load output voltage reaches a second reference voltage lower than the first reference voltage during charging of the first and second capacitors, the power supply control unit controls the fourth and fifth switches to control the first capacitor And controls the second and sixth switches so as to control the charging voltage charged in the second capacitor and the battery voltage To output the first pumping voltage generated by the first pumping voltage as the load output voltage.
12. The method of claim 11,
After the first pumping voltage is output, the power control unit charges the second capacitor again when the load output voltage falls and reaches a third reference voltage higher than the second reference voltage, and when the load output voltage falls, And to discharge the voltage charged in the second capacitor when it reaches the second reference voltage again, and to output the discharge voltage and a second pumping voltage generated by the battery voltage as the load output voltage. Control circuit.
A charging unit including a first capacitor and a second capacitor charged by a battery voltage supplied from a battery and connected in series, and a control unit controlling at least a load output voltage output to the load or a power supply to the charging unit 1. A power supply control method performed by a power supply control circuit including a power supply control unit for controlling one of the power supply control units,
The plurality of switches may include: a first switch connected between the battery and one side of the first capacitor; A second switch connected between the battery and one side of the second capacitor; A third switch connected between the first capacitor and the second capacitor; A fourth switch connected between the battery and the other side of the first capacitor; A fifth switch connected between the first switch and the load; A sixth switch connected between the other side of the second capacitor and the load; And a seventh switch connected between the second switch and ground,
The power supply control method
Controlling the first and fifth switches to output the battery voltage as the load output voltage to the load when the startup is off;
Controlling the first, third, fifth, and seventh switches to charge the charging unit when the load output voltage reaches a first reference voltage; And
And when the load output voltage reaches a second reference voltage lower than the first reference voltage, the second switch, the fourth switch, the fifth switch, and the sixth switch are controlled to discharge the voltage charged in the charging unit, And outputting a first pumping voltage generated by the voltage and the battery voltage as the load output voltage.
delete 14. The method of claim 13,
Controlling to output the first pumping voltage as the load output voltage,
And to discharge the voltage charged in at least one of the first and second capacitors when the load output voltage reaches the second reference voltage so as to output the first pumping voltage by the discharge voltage. Power control method.
16. The method of claim 15,
After the step of controlling to output the first pumping voltage as the load output voltage,
Controlling the third switch, the fourth switch, and the seventh switch to charge the second capacitor again when the load output voltage falls and reaches a third reference voltage higher than the second reference voltage; And
The second switch and the sixth switch are controlled to discharge the voltage charged in the second capacitor when the load output voltage reaches the second reference voltage again, and the second pumping voltage generated by the discharge voltage and the battery voltage So as to output a voltage as the load output voltage.
17. The method of claim 16,
Wherein the first reference voltage and the third reference voltage are the same.
17. The method of claim 16,
After the step of controlling to output the second pumping voltage as the load output voltage,
And turning off the main switch to cut off power supply to the load when the load output voltage reaches a fourth reference voltage lower than the second reference voltage.

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