KR20060121328A - Apparatus and method for controlling charging and discharging - Google Patents

Abstract

An apparatus and a method for controlling charging and discharging are provided to control a charging of the other devices except for a battery by freely adjusting a current value flowing into the battery. In an apparatus for controlling charging and discharging, a precision current control unit(16) accurately controls current flowing from a generator(12) to a battery(14). A load driving unit(18) drives a load(30) by transferring power discharged from the battery(14) to the load(30). A first switch(20) controls supplying or blocking of the power originated in the generator(12) to the battery(14). A second switch(22) controls supplying or blocking of the power from the load driving unit(18) to the load(30) according to a charged state of the battery(14). And, a processor(24) controls the first and second switches(20,22) by monitoring a voltage level charged at the battery(14).

Description

Charge / discharge control device and charge / discharge control method {Apparatus and Method for Controlling Charging and Discharging}

1 is a block diagram showing the configuration of a charge and discharge control device according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a processor shown in FIG. 1.

3 is a view showing the hysteresis characteristics of the storage battery used in the charge and discharge control apparatus of the present invention.

4 is a view showing whether the first switch and the second switch on / off.

FIG. 5 is a flowchart illustrating a process of controlling charge and discharge of a storage battery using the charge and discharge control apparatus shown in FIG. 1.

<Description of the symbols for the main parts of the drawings>

10: charge and discharge control device 12: generator

14: battery 16: precision current control unit

18: load driver 20: first switch

22: second switch 24: processor

26: display unit 28: input voltage selector

The present invention relates to a charging device, and more particularly, to an apparatus and a method for controlling charging and discharging of a battery by monitoring a charging voltage state of the battery.

The charging and discharging device is a device that stores power provided from an external generator in a storage battery and supplies the power to a load if necessary. Here, a solar cell or a wind power generator is mainly used as an external generator for supplying power to a charge / discharge device. The conventional solar cell charging and discharging device is designed to convert solar energy into electrical energy and store it in a storage battery, and supply power stored in the storage battery to the load when power is required to the load. Control the output voltage differently according to weather and time zone.

However, such a conventional charging and discharging device is not uniform in the intensity of sunlight, so the charging and operating point of the battery is constantly changing, the battery is repeatedly charged and discharged, not only to reduce the performance of the battery but also to supply a stable power to the load There was a problem.

In addition, the existing charging and discharging device resumes charging even when the voltage of the battery is slightly lower than the voltage at full charge, and ends charging when the voltage at the time of full charge again is reached, and resumes discharging even if it is slightly higher than the voltage at the time of discharge. When the voltage at the time of discharging was impossible again, the discharging was stopped, and thus there was a problem that charging and discharging was repeated.

In addition, the conventional charging and discharging device was to supply power to the load by controlling the charging voltage of the battery, there was a problem that can not control the charging voltage of various devices other than the battery.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and provides a charge / discharge control device capable of reducing repetitive charge / discharge caused by characteristics of a battery and controlling charge voltages of various devices in addition to the battery. It is a task.

Another object of the present invention is to provide a charge / discharge control method capable of reducing repetitive charge / discharge caused by the characteristics of a battery and controlling charge voltages of various devices in addition to the battery.

Charge and discharge control device according to an embodiment of the present invention for achieving the technical problem is a device for controlling the charge and discharge of the battery is charged using the power input from the generator, the current flowing into the storage battery from the generator Precision current control unit for precise control; A load driving unit which transfers electric power discharged from the battery to a load to drive the load; A first switch configured to supply or cut off power output from the generator to the storage battery; A second switch configured to supply or cut off power supplied to the load from the load driver according to the state of charge of the battery; And a processor configured to control the first switch and the second switch by monitoring a voltage level charged in the storage battery. It includes.

In a preferred embodiment, the processor includes a voltage level detector for monitoring the voltage level input from the generator and the battery to the processor; A voltage level storage unit for storing the voltage level sensed by the voltage level detection unit and reference voltage level information for controlling charge and discharge of the battery; A voltage level comparison unit comparing the voltage level sensed by the voltage detection unit with the reference voltage level; And a hysteresis processor configured to control the first switch and the second switch by monitoring the state of charge of the battery using the result of the voltage level comparator. It further includes.

Here, the reference voltage level is a first reference voltage level and a second reference voltage level that is a reference voltage level for determining whether the battery is charged, and a third reference voltage level that is a reference voltage level for determining whether the battery is discharged. And a fourth reference voltage level, wherein the hysteresis processor ends the charging by opening the first switch when the charging voltage level is equal to or greater than the first reference voltage level, and closing the first switch when the charging voltage level becomes equal to or less than the second reference voltage level. Closes and resumes charging, and when the charge voltage level is less than or equal to the third reference voltage level, the second switch is opened to terminate the discharge; when the charge voltage level is greater than or equal to the fourth reference voltage level, the second switch is closed to resume discharging. It is done.

In a modified embodiment of the present embodiment, the charge / discharge control device further includes a display unit which displays a voltage level input from the generator or a charge voltage level input from the capacitor.

The charge / discharge control device may further include an input voltage selector configured to selectively display the voltage level input from the generator or the charge voltage level input from the capacitor through the display unit.

In another embodiment, the processor includes a voltage level sensing function for monitoring a voltage level output from the generator and the battery to the processor; A voltage level storing function for storing the voltage level sensed by the voltage level detecting unit and reference voltage level information for controlling charge and discharge of the battery; A voltage level comparison function for comparing the voltage level sensed by the voltage sensing unit with the reference voltage level; And a hysteresis processing function of controlling the first switch and the second switch by monitoring the state of charge of the battery using the result of the voltage level comparator. A program including a may be mounted in a firmware format.

Charge and discharge control method according to an embodiment of the present invention for achieving the above another technical problem,

(a) detecting a charge voltage level of the battery; (b) comparing the charging voltage level with a reference voltage level; And (c) a first switch for supplying or cutting off the power output from the generator to the storage battery or a second supplying or cutting off power supplied from the load driver to the load according to a state of charge of the storage battery according to a comparison result. Controlling the switch; It includes.

In a preferred embodiment, in step (b), the reference voltage level is a reference voltage level for determining whether the battery is charged or not and a reference for determining whether the battery is discharged. And a third reference voltage level and a fourth reference voltage level, which are voltage levels, and stop charging when the charging voltage level is equal to or greater than the first reference voltage level, and resume charging when the charging voltage level is less than or equal to the second reference voltage level. The discharge is terminated when the charge voltage level becomes less than or equal to the third reference voltage level, and resumes when the charge voltage level becomes equal to or greater than the fourth reference voltage level.

In addition, the step (a) further comprises the step of detecting the voltage level input from the generator,

(d) displaying one selected by a user from an output voltage level of the generator and a charging voltage level of the battery; It further includes.

In an exemplary embodiment, the method may further include precisely controlling a current flowing into the storage battery from the generator in any one of steps (a) or (c).

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

1 is a view showing the configuration of a charge and discharge control apparatus according to an embodiment of the present invention. Charge and discharge control device 10 according to the present invention receives the power generated from the generator 12 is stored in the storage battery 14 and controls the charging voltage of the storage battery. In one embodiment, the generator 12 may generate power by converting solar energy into electrical energy using a solar cell (not shown), and in a modified embodiment, wind energy using a wind generator (not shown). Can be converted into electrical energy to generate power.

Referring to FIG. 1, the charge / discharge control apparatus 10 according to the present invention includes a precision current controller 16, a load driver 18, a first switch 20, a second switch 22, a processor 24, and a display unit. And an input voltage selector 28.

The precision current controller 16 precisely controls the current flowing into the storage battery 14 from the generator 12. In one embodiment, the precision current control unit 16 detects the charging state of the device to be charged (not shown) when the device other than the battery 14 is charged using the charge / discharge control device 10 according to the present invention. It is possible to precisely control the current flowing into the device to be charged. At this time, the precision current controller 16 can control the charging voltage of various devices because the current value flowing from the generator 14 to the charged device can be arbitrarily set to allow a current having a specific value to flow into the charged device. have.

The load driver 18 transfers electric power discharged from the storage battery 14 to the load 30 to drive the load. The load driver 18 receives the control signal of the processor 24 according to the state of charge of the battery 14 to open and close the second switch 22 to transfer power to the load 30.

The first switch 20 is connected between the generator 12 and the processor 24 to supply or cut off power generated from the generator 12 to the storage battery 14 according to a control signal of the processor 24. The second switch 22 is connected between the load driver 18 and the load 30 to supply or cut off power stored in the battery 14 to the load 30 according to a control signal of the processor 24.

The processor 24 monitors the state of charge of the battery 14 to control the first switch 20 and the second switch 22 to reduce repetitive charging and discharging of the battery 14. The configuration of the processor 24 will be described in detail with reference to FIG. 2. As illustrated, the processor 24 includes a voltage level detector 32, a voltage level storage unit 34, and a voltage level comparison unit 36. ) And a hysteresis processing unit 38.

The voltage level detector 32 monitors the voltage level input from the generator 12 and the battery 14 to the processor 24. That is, the voltage level detector 32 measures the voltage level input from the generator 12 to the processor 24 and the charging voltage level input from the battery 14 to the processor 24 at predetermined time intervals. The result is stored in the voltage level storage 34.

The voltage level storage unit 34 stores the input voltage level from the generator 12 measured by the voltage level detector 32, the input voltage level from the storage battery 14, and the reference voltage level. Here, the reference voltage level means a reference voltage level used to determine whether the storage battery 14 is charged or discharged. The reference voltage level is a value input in advance according to the voltage characteristics of the storage battery 14.

In one embodiment, the reference voltage level includes a first reference voltage level, a second reference voltage level, a third reference voltage level, and a fourth reference voltage level. The first reference voltage level means a voltage level when the battery 14 is fully charged, and the second reference voltage level means a voltage level when the battery 14 resumes charging, and the third reference voltage level. Means a voltage level when the battery 14 cannot discharge power to the load 30, and the fourth reference voltage level indicates that the battery 14 resumes discharging to supply power to the load 30. It means the possible voltage level.

The voltage level comparing unit 36 compares the charging voltage level of the storage battery 14 detected by the voltage level detecting unit 32 with the reference voltage level, and provides the result to the hysteresis processing unit 38 to thereby provide the hysteresis processing unit 38. It is to determine whether or not the storage battery (14).

The hysteresis processor 38 determines whether the battery 14 is charged or discharged by controlling the first switch 20 and the second switch 22 using the voltage level comparison result received from the voltage level comparator 36. . For example, it is assumed that the first reference voltage level is 14.4V, the second reference voltage level is 13.8V, the third reference voltage level is 10.8V, and the fourth reference voltage level is 12.4V. Referring to the case of charging 14, when the charge voltage level of the battery 14 detected by the voltage level detector 32 is 14.4 V or more, the hysteresis processor 38 opens the first switch 10 to generate a generator ( No power is supplied to the charge / discharge control device 10 from 12).

When the voltage of the battery 14 decreases again due to the discharge and the detected charge voltage level of the battery 14 is 13.8V or less, the hysteresis processor 38 closes the first switch 20 to resume power from the generator 12. The battery 14 is charged by being supplied.

Next, the case of supplying power to the load 30 by discharging the power stored in the battery 14, the hysteresis when the charge voltage level of the battery 14 sensed by the voltage level detecting unit 32 is 10.8V or less The processor 38 opens the second switch 22 to prevent the power of the storage battery 14 from being discharged to the load 30. After the discharge is stopped, when the voltage of the storage battery 14 increases due to charging and the detected voltage level of the storage battery 14 becomes 12.4 V or more, the hysteresis processing unit 38 closes the second switch 22 to store the storage battery 14. Power is discharged to the load 30.

3 shows the hysteresis characteristics of the storage battery 14 used in the charge / discharge control device 10 of the present invention. Referring to FIG. 3 (a) illustrating the state of charge of the battery 14, when the charge voltage level of the battery 14 is 14.4 V or higher, a low level signal is output to stop the charge and the charge voltage level is 13.8 V. If it decreases, it will be high level and charging will resume. Referring to FIG. 3 (b) illustrating the discharge state of the battery 14, when the charge voltage level of the battery 14 is 10.8 V or less, the battery 14 becomes low level when the discharge is stopped and the charge voltage level rises to 12.4 V. It can be seen that the discharge is resumed at the high level.

In one embodiment, when the charge / discharge control device 10 of the present invention charges the storage battery 14 by using the power generated from the solar cell, the storage battery 14 is supplied to the load 30 during the day time when the storage battery 14 is charged. In order to cut off the power, the hysteresis processor 38 preferably closes the second switch 22. In this case, the hysteresis processor 38 may detect a voltage level input from the generator 12 to classify time zones. In a modified embodiment, the hysteresis processor 38 may include a light sensor (not shown) to classify time zones.

The change of the charge / discharge of the battery according to the time period is described with reference to whether the first switch 20 and the second switch 22 are turned on or off through 4, first, the first switch 20 is used during the day and at night. Irrespective of the result of the comparison between the charging voltage level of the battery 14 and the reference voltage level, the battery 14 is turned on and off. As shown in the figure, it can be seen that the charging operation of the battery 14 is stopped when the charging voltage level of the battery 14 is 14.4V or more.

Next, the second switch 22 is always off during the daytime, so that the discharge of the battery 14 does not occur, and at night, except for the case of 10.8 V or less, which is the voltage level of the non-dischargeable state of the rechargeable battery 14. It can be seen that it is turned on to supply power to the load 30.

Referring back to FIG. 1, the display unit 26 displays the voltage level input from the generator 12 or the storage battery 14 to the processor 24. In an exemplary embodiment, the display unit 26 may be implemented as a seven segment, which is a light emitting device. The input voltage selector 28 allows a user to select an input voltage to be displayed through the display unit 26 between the input voltage from the generator 12 and the input voltage from the storage battery 14.

Referring to FIG. 5, a method of controlling charge / discharge of the storage battery 14 by using the charge / discharge control apparatus 10 of the present invention as described above, first, the voltage level detecting unit 32 of the current storage battery The charging voltage level is sensed and the detected voltage level is stored in the voltage level storage unit 34 (operation 100). The charging state of the current rechargeable battery is determined by comparing the voltage level detected by the voltage level detecting unit 32 with a reference voltage level previously stored in the voltage level storing unit 34 (step 110). . When the charging voltage level is greater than the first reference voltage level, the first switch 20 is opened (step 130) to terminate charging (step 140). When the charging voltage level is smaller than the second voltage level, the first switch ( 20) and charging is resumed (step 150).

In one embodiment, when the charge / discharge control device 10 of the present invention receives power from a solar cell (not shown) to charge the storage battery 14, the hysteresis processor 38 determines day and night (the Step 170). If the determination result is low, the second switch is opened (step 180) and the discharge is terminated to cut off the power supplied to the load 30 (step 190). At night, first, when the charge voltage level is smaller than the third reference voltage level, the second switch 22 is opened (step 200) to end the discharge (step 210), and the charge voltage level is greater than the fourth reference voltage level. If the second switch 22 is closed (step 220), the discharge is resumed and power is supplied to the load 30 (step 230).

In the modified embodiment, when the charge / discharge control device 10 of the present invention receives power from a generator of a type other than a solar cell to charge the storage battery 14, the charge voltage level and the power supply do not need to be determined. The discharge can be determined by comparing the third and fourth reference voltage levels.

Meanwhile, when the charging voltage level or the input voltage from the generator 14 is to be displayed through the display unit 28, the output voltage level from the generator 14 is detected following the 100th step of detecting the charging voltage level ( Step 240). Next, a user's selection is input through the input voltage selector 28 (operation 250). When the user selects the display of the input voltage level from the generator 14, the input voltage level from the generator 14 is displayed. In operation 260, when the user selects an output display of the charging voltage level of the battery 14, the charging voltage level is displayed (operation 270).

Meanwhile, the charging and discharging control method of the present invention further includes the step of precisely controlling the current flowing into the storage battery 14 from the generator 12 in any one of the above-described steps to prevent charge and discharge of various devices. Can be controlled.

In the present embodiment, the charging voltage level is measured first, but in the modified embodiment, it is obvious that the input voltage level from the generator 14 may be measured first or both voltage levels may be measured simultaneously. to be.

In another embodiment, the charge / discharge control device 10 according to the present invention includes a time setting unit (not shown), so that the user may arbitrarily set a discharge time in consideration of seasonal characteristics and use environment, and the generator 12 ) Is implemented as a solar cell (not shown), the user may set the sunrise and sunset times.

Those skilled in the art should understand that the present invention can be implemented in other specific forms without changing the technical spirit or essential features of the present invention. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

For example, although the voltage level detecting unit, the voltage level storing unit, the voltage level comparing unit, and the hysteresis processing unit are described as separate components constituting the processor, in the modified embodiment, the voltage level detecting unit, the voltage level storing unit, Voltage level comparison and hysteresis processing can be implemented as a program that is embedded in the processor in the form of firmware. In this case, the processor may be implemented in PIC, and the program may be written using a high-level language dedicated to a PIC microprocessor called CSCC-C. The written source program is compiled into a machine language and then stored in EEPROM, a memory inside the microprocessor. Therefore, the stored program can remain even after the power supply of the PIC is removed.

The scope of the invention is indicated by the following claims rather than the above description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the invention. do.

As described above, according to the present invention, by sensing the voltage of the battery and effectively controlling the power supply between the generator and the battery, the battery and the load, it is possible to reduce the repetitive charging and discharging caused by the characteristics of the battery. It can be extended.

In addition, since the present invention can arbitrarily specify the value of the current flowing into the battery, it is possible to control the charging of other devices in addition to the battery, thereby having an effect of wide application range.

In addition, the present invention has the effect that the user can arbitrarily set the discharge time in consideration of the seasonal characteristics and the use environment.

Claims (10)

A device for controlling charging and discharging of a battery that is charged by using electric power input from a generator, Precision current control unit for precisely controlling the current flowing into the storage battery from the generator; A load driving unit which transfers electric power discharged from the battery to a load to drive the load; And A first switch configured to supply or cut off power output from the generator to the storage battery; A second switch configured to supply or cut off power supplied to the load from the load driver according to the state of charge of the battery; A processor configured to control the first switch and the second switch by monitoring a voltage level charged in the storage battery; Charge and discharge control device comprising a. The method of claim 1 wherein the processor is A voltage level detector for monitoring a voltage level input from the generator and the battery to the processor;  A voltage level storage unit for storing the voltage level sensed by the voltage level detection unit and reference voltage level information for controlling charge and discharge of the battery; A voltage level comparison unit comparing the voltage level sensed by the voltage detection unit with the reference voltage level; And A hysteresis processor configured to control the first switch and the second switch by monitoring the state of charge of the battery using the result of the voltage level comparator; Charge and discharge control device further comprising a. The method of claim 2, The reference voltage level may include a first reference voltage level and a second reference voltage level, which are reference voltage levels for determining whether the battery is charged, a third reference voltage level, which is a reference voltage level for determining whether the battery is discharged, and Including a fourth reference voltage level, The hysteresis processing unit ends the charging by opening the first switch when the charging voltage level is greater than or equal to the first reference voltage level, and restarts charging by closing the first switch when the charging voltage level is less than or equal to the second reference voltage level. When the charging voltage level is less than or equal to the third reference voltage level, the second switch is opened to terminate the discharge, and when the charge voltage level is greater than or equal to the fourth reference voltage level, the second switch is closed to resume discharging. . According to claim 2, wherein the charge and discharge control device And a display unit for displaying the voltage level input from the generator or the charging voltage level input from the capacitor. According to claim 4, wherein the charge and discharge control device And an input voltage selector configured to selectively display a voltage level input from the generator or a charge voltage level input from the capacitor through the display unit. The processor of claim 1, wherein the processor A voltage level sensing function for monitoring a voltage level output from the generator and the battery to the processor;  A voltage level storing function for storing the voltage level sensed by the voltage level detecting unit and reference voltage level information for controlling charge and discharge of the battery; A voltage level comparison function for comparing the voltage level sensed by the voltage sensing unit with the reference voltage level; And A hysteresis processing function of controlling the first switch and the second switch by monitoring the state of charge of the battery using the result of the voltage level comparator; Charge and discharge control device, characterized in that the program containing a firmware type. A method of controlling charging and discharging by using a device for controlling charging and discharging of a battery that is charged by using power output from a generator, (a) detecting a charge voltage level of the battery; (b) comparing the charging voltage level with a reference voltage level; And (c) a first switch for supplying or cutting off the power output from the generator to the storage battery according to a comparison result or a second switch for supplying or cutting off the power supplied from the load driving part to the load according to the state of charge of the storage battery; Controlling; Charge and discharge control method comprising a. The method of claim 7, wherein in step (b) The reference voltage level is a first reference voltage level and a second reference voltage level, which are reference voltage levels for determining whether to charge the battery, and a third reference voltage level and a fourth reference voltage level, which is a reference voltage level for determining whether the battery is discharged. Including the reference voltage level, When the charging voltage level is greater than or equal to the first reference voltage level, the charging is terminated. When the charging voltage level is less than or equal to the second reference voltage level, charging is resumed. Discharging is terminated when the charging voltage level is equal to or lower than the third reference voltage level, and discharging is resumed when the charging voltage level is equal to or greater than the fourth reference voltage level. The method of claim 7, wherein the step (a) further comprises the step of detecting the voltage level input from the generator, (d) displaying one selected by a user from an output voltage level of the generator and a charging voltage level of the battery; Charge and discharge control method characterized in that it further comprises. The charging and discharging control method of claim 7, further comprising precisely controlling a current flowing from the generator to the storage battery in any one of steps (a) and (c).

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