KR101559293B1 - Device for measuring residual capacity of battery and apparatus for controlling battery power using the same - Google Patents

Abstract

Disclosed are an apparatus for measuring state of charge of a battery and a battery power controlling apparatus using the same which can assure the reliability of a battery power source in a solar cell independent power system such as a photovoltaic street lamp system and an independent lighting system using sunlight. The apparatus for measuring the state of charge of battery includes: a storage part which is connected to a charging control part charging the battery by a pulse width modulation (PWM) charging method, and stores PWM duty ratio of the charging control part; and an extraction part which extracts a specific PWM duty ratio stored at the last time in a previously established time period among PWM duty ratios stored in the storage part, and then outputs the specific PWM duty ratio.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a battery remaining capacity measuring device and a battery power control device using the battery remaining capacity measuring device.

Embodiments of the present invention relate to a battery remaining capacity measuring apparatus, and more particularly, to a battery residual capacity measuring apparatus, a battery capable of securing the reliability of battery power in a solar cell independent power source type apparatus such as a solar street lamp system, A remaining capacity measuring device and a battery power control device using the same.

A battery is a device that converts chemical energy into electrical energy. The battery basically has a structure in which an anode and a cathode, which are two electrodes, are disposed with an electrolyte interposed therebetween, and have a non-rechargeable form or a rechargeable form.

In a variety of mobile electronic devices such as mobile phones, notebook computers, portable game machines, and electronic books, and automobiles, various industrial and household facilities, and independent power source streetlight devices, the battery is used as a power source. Commercial power from utility companies can only be supplied if the infrastructure of electrical equipment is available, so batteries are an excellent alternative to power supplies where the electrical infrastructure is not properly equipped. Since a battery used in various environments stores a limited amount of electric charges, power can be supplied only for a limited period of time. There are various alternative energy sources besides the commercial power source for storing power in the battery, among which the most useful alternative energy is solar light.

When all the charge in the battery is discharged, the electronic devices can no longer operate, and if the battery is overdischarged, the service life of the battery may be shortened. Therefore, the electronic device should measure the remaining amount of the battery in real time and output it so that the user can check it. This allows users to check the remaining amount of the battery and selectively use the functions of the electronic device according to the remaining amount of the battery or charge the battery so that the battery is not discharged. Therefore, in order to make such judgment of users, a technique of accurately measuring the remaining amount of the battery is required. For example, in the case of an electric vehicle, since power supplied from a battery is used as power, it is very important to accurately measure the remaining amount of the battery.

In particular, in the case of solar street lamps, even if the solar panel can not generate electricity due to rain or clouds, it is necessary to be able to light the lamp (LED lamp, etc.) for a predetermined time or the number of days. In the case of a solar streetlight system, the number of days of relief is set so that it can normally be turned on for at least 10 hours for 3 days.

A method of calculating a state of charge (SoC) of a battery includes calculating a state of charge (SoC) by subtracting a used capacity from a predetermined reference capacity based on a relationship between a used current Ampere and a time (hour) An impedance measurement method for calculating the remaining battery level in relation to the internal impedance of the battery and the remaining battery level, and the like.

The current integration method is a method of estimating the remaining capacity by a product of a discharge current and time, and there is a disadvantage that an error with respect to the battery remaining amount measurement increases as time goes by due to accumulation of current or time error. That is, when the current or time is measured to be smaller than the actual value, the estimated value of the remaining battery capacity may be measured to be larger than the actual remaining battery capacity with the passage of time. Further, when the current or time is measured to be larger than the actual value, the estimated value of the remaining battery power may be measured to be smaller than the actual remaining battery power with the passage of time.

The impedance measurement method calculates the residual capacity of the battery by detecting the change of the internal impedance of the battery when the battery is being charged or discharged, that is, when the current is flowing. Therefore, the calculation is performed according to the changing internal impedance. There is a disadvantage that estimation can not be performed.

Furthermore, the above-described conventional battery residual quantity measurement method is not a method of measuring the open circuit voltage (OCV) of the battery in the battery management system, but rather a method of measuring the closed circuit voltage (CCV) As a method of measuring the remaining amount of the battery, there is a problem that a large amount of error occurs due to deterioration of the battery.

Further, in the battery power control apparatus using the above-described conventional battery remaining amount measuring method, since the output of the battery is controlled by using the remaining battery residual amount measuring method with a large error, In addition, not only can the battery efficiency of the solar-powered power-supply type lighting system be reduced, but also the proper discharge control can not be performed according to the battery state, thereby shortening the life of the battery, The reliability of the power supply type illumination system is deteriorated.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a battery remaining capacity measuring device capable of reliably measuring a battery remaining capacity in an embodiment of the present invention.

Another embodiment of the present invention is to provide a battery power control apparatus capable of improving the reliability of a system using the above-described remaining battery capacity measuring apparatus.

According to an aspect of the present invention, there is provided an apparatus for measuring remaining capacity of a battery, comprising: a storage unit connected to a charge control unit for charging a battery in a pulse width modulation (PWM) charging mode and storing a PWM duty ratio of the charge control unit; And an extracting unit for extracting and outputting a specific PWM duty ratio stored at a latest time among a preset time interval among the PWM duty ratios stored in the storage unit.

In one embodiment, the PWM charging scheme may include a scheme of charging the battery under constant voltage conditions, such as reducing the amount of charging current for the battery in response to the remaining battery capacity that increases with the elapse of charging time. Here, the specific PWM duty ratio may correspond to a specific battery remaining capacity.

According to another aspect of the present invention, there is provided an apparatus for controlling a battery power, comprising: a charge controller for charging the battery under a constant voltage condition by a pulse width modulation (PWM) charging method; A memory system for storing a decrementing PWM duty ratio corresponding to a remaining battery capacity of the memory system; a memory system for extracting a most recently stored specific PWM duty ratio within a predetermined time interval among the PWM duty ratios stored in the memory system, An extraction unit that extracts a specific battery remaining amount of the battery corresponding to the battery remaining amount, and a discharge control unit that controls the consumed power of the battery based on the specific battery remaining amount.

In one embodiment, the control unit or charge / discharge control circuit of the battery power control apparatus extracts a battery operation mode corresponding to a specific battery remaining amount, and controls the discharge operation of the battery according to a preset operation mode in the extracted battery operation mode .

In one embodiment, the control unit of the battery power control apparatus or the charge / discharge control circuit can perform a dimming control for the lamp according to a predetermined operation mode of the battery operation mode, the lamp connected to the battery.

In one embodiment, the control unit or charge / discharge control circuit of the battery power control apparatus is controlled by a predetermined time period according to the lapse of the relief day so that the solar power system including the solar street lamp system to which the lamp is coupled Or to control the operation of the lamp in a plurality of different battery operating modes each day.

According to the present invention, it is possible to provide a remaining battery capacity measuring device capable of reliably measuring the remaining battery capacity. That is, the remaining capacity of the battery can be efficiently and reliably measured by measuring the remaining capacity of the battery using a charging technique that efficiently charges the generated power of the solar cell to the battery.

In addition, according to the present invention, it is possible to provide a battery power control apparatus capable of improving reliability of battery power in a system using battery power as a sole power source or a main power source. Particularly, the battery power control apparatus of the present embodiment predicts the remaining capacity of the battery based on the data obtained from the remaining battery capacity measuring apparatus, and sets the driving characteristics of the system according to the predicted remaining battery capacity to control the discharge power of the battery, It has the effect of increasing the efficiency, preventing the damage of the battery, and substantially extending the life of the battery.

1 is a block diagram of an apparatus for measuring remaining capacity of a battery according to an embodiment of the present invention.
FIG. 2 is a graph for explaining the operation principle of the charge control unit of the remaining battery capacity measuring apparatus of FIG.
FIG. 3 is a flowchart showing the operation of the remaining battery capacity measuring device of FIG. 1
FIGS. 4 to 6 are illustrations of battery charge / discharge curves that can be used in the battery remaining capacity measuring device of FIG.
7 is a schematic diagram of a stand-alone solar power system employing a battery power control apparatus according to another embodiment of the present invention
8 is a block diagram of the battery power control apparatus of FIG.
Fig. 9 is a flowchart of the operation of the battery power control apparatus of Fig.
10 is an exemplary diagram of an operation mode that can be employed in the battery power control apparatus of FIG.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. Like reference numerals are used for like elements in describing each drawing.

The terms first, second, A, B, etc. may be used to describe various elements, but the elements should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as being consistent with the meanings in the context of the relevant art and are not to be construed as ideal or overly formal meanings unless explicitly defined in the present application.

1 is a block diagram of an apparatus for measuring remaining capacity of a battery according to an embodiment of the present invention. FIG. 2 is a graph for explaining the operation principle of the control unit of the remaining capacity measuring apparatus of FIG. 1; FIG.

Referring to FIG. 1, the apparatus 10 for measuring remaining capacity of a battery according to the present embodiment includes a charge control unit 11, a storage unit 12, and an extraction unit 13.

The charging control unit 11 controls the power supplied from an external power source such as a solar cell to charge the battery when the battery is charged. The charge control unit 11 can control the amount of charge charged in the battery by controlling the pulse width by a PWM (Pulse Width Modulation) method that adjusts the duration of the pulse according to the voltage of the signal wave (sinusoidal wave or the like).

In particular, the charge control unit 11 controls the charge of the battery by controlling the pulse width in accordance with the remaining amount (SOC) of the battery. For example, as shown in FIG. 2, when the battery control unit 11 charges the battery by the PWM control method, the duty ratio of the PWM becomes 0% or 0% as the remaining battery level (SOC) approaches 100% And the PWM duty ratio is set to a value that is directly proportional to the increase in the battery residual amount by utilizing the value that is close to the value, thereby controlling the charging of the battery while reliably estimating the residual amount of the battery. Here, when the battery remaining amount is the minimum value (MIN, Minimum), the charge control section 11 operates the switch of the charging circuit under the condition of the maximum pulse width (MAX, Maximum) It can be charged.

The charging control unit 11 described above may be a PWM control unit including a semiconductor switch, but is not limited thereto. The charge control unit 11 may be a unit that performs PWM control or a component that performs a function corresponding to this means. For example, the charge control unit 11 may be implemented with at least some functional units or components of a control device using a logic circuit using a flip-flop, a microcomputer, or a microprocessor. Here, the control device may include an arithmetic logic unit (ALU) for performing calculations, a register for temporarily storing data and instructions, and a controller for controlling or managing the inter-middleware interface device.

The storage unit 12 stores the duty ratio of the pulse width modulation of the charge control unit 11. [ In addition, the storage unit 12 may store data related to the battery remaining amount corresponding to the duty ratio. Data on the correspondence relationship between the PWM duty ratio and the battery remaining amount can be stored in the storage unit 12 in the form of a look-up table.

In addition, the storage unit 12 may store the recorded program of the remaining battery capacity measurement method implemented in the battery remaining capacity measurement apparatus, but is not limited thereto. Such a program may be temporarily stored in the storage unit 12 through a user interface (not shown) such as an input device or a communication unit (not shown) connected to the network. The storage unit 12 may include a main memory in the form of a storage medium such as a RAM (Random Access Memory) and a ROM (Read Only Memory), a long-term memory such as a floppy disk, a hard disk, a tape, a CD- term < / RTI > storage medium.

The extracting unit 13 extracts a specific PWM duty ratio stored in the storage unit 12 at the latest time of the charging interval among the PWM duty ratios stored in the battery charging period. The extraction unit 13 extracts a specific PWM duty ratio corresponding to the latest time in a predetermined time period or PWM charging mode section while comparing the duty ratio of the charge control unit 11 in real time, It is possible to output a signal for a specific battery remaining amount corresponding to the duty ratio. The extractor 13 may be embodied as at least some of the functional units and components of the control unit connected to the storage unit 12.

On the other hand, in the present embodiment, it is described that the remaining battery capacity measuring device includes the charge controller 11, but the present invention is not limited to this. For example, the remaining battery capacity measuring device is a control device such as a solar battery charge control device or a battery power control device, and is connected to a device for controlling the charge / discharge of the battery so as to control the PWM duty ratio for battery charging Or at least some of the functionalities and components of the system.

In this embodiment, the rechargeable battery includes a secondary battery, a lead-acid battery, a Ni-Cd battery, a Ni-MH battery, and the like. In particular, the battery applicable to the present embodiment may include a characteristic in which the PWM duty ratio is proportionally reduced according to the remaining battery level during the constant voltage charging of the PWM system, or all the batteries having at least a constant characteristic interval.

3 is an operational flowchart of the remaining battery capacity measuring device of FIG.

3, in order to effectively control an apparatus (a solar street lamp system or the like) which is driven by battery power by accurately estimating the remaining capacity of the battery effectively, a battery residual capacity measuring apparatus according to the present embodiment includes the following series of It can be operated according to the procedure.

In the present embodiment, the stand-alone solar streetlight system will be mainly described for the convenience of explanation. However, the present embodiment is not intended to limit the present invention as a most preferred embodiment. The battery remaining capacity measuring device of the present embodiment is applicable to various devices that are charged by a PWM control method and driven by using battery power as a single power source or a main power source.

First, the remaining battery capacity measuring device charges the battery through PWM control using the control device or the charge control section (S31). The charge control unit may be configured to automatically set a duty ratio (D / R) for PWM control according to a load characteristic indicated by a battery charging circuit or a battery connected to the charge / discharge circuit. Here, the load characteristic may include a characteristic that a required amount of current varies depending on a preset voltage and a battery charging state when the battery is charged at a constant voltage.

The charging control unit includes a constant voltage charging section and a constant current charging section in accordance with the remaining amount of the battery. In the constant voltage charging section, the battery is charged to a constant voltage of a duty ratio automatically set according to the load state of the battery. It is possible to charge the battery with a constant current having a duty ratio that is automatically set in accordance with the duty ratio.

Next, the remaining battery capacity measuring apparatus stores the duty ratio (D / R) of the PWM control for a predetermined time through the storage unit (S32). The predetermined time may be 24 hours a day, a time less than 24 hours, such as 3, 6 or 12 hours, or a time greater than 24 hours, such as 36, 48 hours, and so on. In particular, the predetermined time in this embodiment may be a time period corresponding to at least a part of a period for charging the battery with a constant voltage. In this case, when the battery is charged with the constant voltage, the duty ratio can be repeatedly lowered slightly if the battery terminal voltage becomes larger than the reference voltage based on the reference voltage set to a specific voltage in the constant voltage charging mode. The battery charging mode can be controlled in such a manner that the duty ratio is decreased.

Next, the battery remaining capacity measuring apparatus extracts the latest duty ratio among the duty ratios (D / R) stored in the storage unit during at least a partial period of at least the constant voltage charging mode period (S33). The latest duty ratio is a duty ratio that is stored at a later time in time among the duty ratios stored in the storage unit within a predetermined time period.

Next, the remaining battery capacity measuring device extracts the remaining battery level (SOC) corresponding to the latest duty ratio (D / R) (S34). The remaining battery capacity measuring device may extract a specific battery remaining amount matched with the latest duty ratio by referring to the lookup table stored in the storage unit and output a signal corresponding to the specific remaining battery amount. The output signal may have a signal type or a level corresponding to a specific battery residual amount, but is not limited thereto.

4 to 6 are illustrations of battery charge / discharge curves that can be used in the battery remaining capacity measuring apparatus of FIG.

Referring to FIG. 4, the battery charge / discharge curve G1 shows an example of the remaining battery level (SOC) that varies from 0 to 24 hours on a specific battery.

That is, the battery is discharged from 0:00 to 6:00 and is charged through a battery charging circuit connected to the solar cell from 6:00 to 18:00, and then has a cycle of discharging again from 21:00 to 24:00. Also, the battery can draw discharge curves d1, d2, and d3 of different shapes (inclination, etc.) according to the difference in power consumption depending on the load in the discharge interval after 21:00.

In addition, in the battery charging section of the present embodiment, the battery charging circuit charges the battery with the first duty ratio from 6:00 to 9:00 to raise the remaining battery level (SOC) from about 40% to about 47% The battery charge is increased from about 47% to about 60% by charging the battery with the second duty ratio until the battery is charged at the third duty ratio from 12:00 to 14:00, and the remaining battery charge is increased from about 60% to about 90% , And may operate to charge the battery with the fourth duty ratio from 14:00 to 16:00 to raise the remaining battery level from about 90% to 100%. Here, the period from 12:00 to 14:00 corresponds to the maximum power generation period of the solar cell, whereby the third duty ratio of the battery charging circuit may be smaller than the first, second or fourth duty ratio.

According to the battery charging / discharging curve G1, the battery charging circuit or the charging controller gradually reduces the duty ratio according to the remaining battery power in the constant voltage charging section of the PWM system and can perform the constant voltage charging operation for the battery. The constant voltage charging period may be from 6 to 15 hours, but is not limited thereto.

In the case of a lead-acid battery, which is a type of battery, it is charged to 14.4 V at constant voltage charging. At this time, when the battery voltage is maintained at 14.4 V, the duty ratio of PWM is adjusted to limit the amount of current charged according to the remaining battery capacity. More specifically, for example, assuming that the duty ratio of PWM for constant voltage charging is 0.5 when the remaining battery level is 60%, the battery charged for a certain period of time is charged at a current duty ratio of 0.5 So that a voltage higher than 14.4 V is obtained. Therefore, the battery charging circuit or the charge control unit changes the duty ratio to a duty ratio different from 0.5 or less to charge the battery for constant voltage charging. Here, the other duty ratio may be a duty ratio smaller than the current duty ratio by a predetermined amount.

Thus, the charge control unit or the battery charging circuit can perform the battery charging operation while gradually reducing the duty ratio of the PWM by measuring the battery voltage that varies depending on the remaining battery level during the constant voltage charging operation. If the battery is fully charged or close to full charge, the duty ratio of the PWM can be close to 0 or 0%.

Also, the storage unit connected to the charge control unit can store the PWM duty ratio from 6:00 to 18:00 or from 6:00 to 15:00. The comparison unit connected to the charge control unit or the storage unit may extract the duty ratio having the smallest value among the PWM duty ratios of the charge control unit in the constant voltage charge period and output the extracted duty ratio information.

According to the above-described configuration, the remaining battery capacity measuring device can output specific duty ratio information corresponding to the battery remaining amount to provide the battery power control device and the like. The battery power control device, etc., The battery remaining amount (SOC) of the present battery can be estimated very effectively and reliably by extracting the battery remaining amount corresponding to the remaining battery remaining amount values stored in advance based on the non-information.

Referring to FIG. 5, the battery charge / discharge curve G2 shows an example of the remaining battery level (SOC) of a specific battery varying from 0 to 24 hours on a specific battery.

That is, the battery has an operation cycle of discharging from 0:00 to 6:00 and discharging from 14:00 to 24:00 after being charged through a battery charging circuit connected to the solar cell from 6:00 to 14:00.

The present embodiment can be applied to a case where the solar cell is generated from 6 to 14 o'clock due to weather or the like and the charge control unit charges the battery with the generated power of the solar cell from 6 to 14 o'clock.

According to the battery charge / discharge curve G2, the charge control section can charge the battery with a constant voltage from 6 o'clock to 14 o'clock. At this time, the duty ratio gradually decreases according to the remaining battery level, and the duty ratio has the smallest value at the time when charging stops within the constant voltage section. Therefore, in the present embodiment, the battery remaining capacity measuring device or the comparing unit can extract the duty ratio of the latest one of consecutive single constant voltage charging sections with a specific duty ratio for estimating the remaining battery capacity.

Referring to FIG. 6, the battery charge / discharge curve G3 shows an example of the remaining battery level (SOC) that varies from 0 to 24 hours on a specific date on a specific battery.

That is, the battery is discharged from 0:00 to 6:00, charged from the battery charging circuit connected to the solar cell from 6:00 to 9:00, charged and discharged from 9:00 to 17:00, and charged from 16:00 to 18:00 And has an operation cycle of discharging from 21:00 to 24:00 without being charged or discharged from 18:00 to 21:00.

According to the battery charge / discharge curve G3, the charge control section can have a first constant voltage charge section from 6:00 to 9:00 and a second constant voltage charge section from 16:00 to 18:00. At this time, the battery remaining capacity measuring device or the comparator can extract and output the PWM duty ratio of the latest one of the first and second constant voltage charging sections. The PWM duty ratio extracted in the present embodiment becomes a value immediately before the constant voltage charging is stopped at around 18 o'clock.

Meanwhile, in this embodiment, the PWM duty ratio extracted by the battery charge / discharge curve G3 may be the smallest value among the constant voltage charging sections, but the present invention is not limited thereto. For example, the PWM duty ratio of the latest time in the constant voltage charging section within a predetermined time according to the battery charging curve such as the shape having the discharge characteristic between 9 o'clock and 15 o'clock is the smallest value among the PWM duities in the constant- But can have a median value or a value close to the maximum value.

7 is a schematic configuration diagram of a stand-alone solar power system employing a battery power control apparatus according to another embodiment of the present invention.

7, the independent solar power system according to the present embodiment includes a solar array (PV array) 2, a DC / DC converter 4, a battery 6, a remaining battery capacity measuring device 10, And a battery power control device (20). The solar power system may further include another DC / DC converter or DC / AC converter 40 that converts the output power of the battery 6 according to the characteristics of the load 50. [

The solar array (PV array) 2, the DC / DC converter 4, and the battery 6 are well known in the art, so that detailed description thereof will be omitted.

The remaining battery capacity measuring apparatus 10 may be any one of the embodiments described above with reference to Figs.

The battery power control device 20 controls the charging of the battery 6 based on the generated power of the solar cell array 2 and controls the discharge of the energy stored in the battery 6 (6) can be controlled. Further, the battery power control device 20 acquires a specific PWM duty ratio from the remaining battery capacity measuring device 10, extracts the battery remaining amount corresponding to the previously obtained PWM duty ratio from the previously stored remaining battery power information, The current battery remaining amount of the battery can be stored beforehand, and the power consumption or discharge mode of the battery can be determined according to the current remaining battery amount.

The DC / DC converter 4, the remaining battery capacity measuring device 10, and the battery power control device 20 may be at least a part of the solar power control device 30.

8 is a block diagram of the battery power control apparatus of FIG.

8, the battery power control apparatus 20 according to the present embodiment includes a charge / discharge circuit 21, a switch 22, a charge control section 23, a discharge control section 24, a memory system 26, A receiving unit 27 and an extracting unit 28. The charge / discharge circuit 21, the switch 22, the charge control section 23, and the discharge control section 24 may be at least a part of the charge / discharge control circuit 25.

The charge / discharge circuit 21 is connected to a solar cell array mounted on the solar power system under the control of the charge controller 23 in the charge mode to store the solar power in the battery. The charge / discharge circuit 21 supplies energy stored in the battery to the load under the control of the discharge control section 24 in the discharge mode.

The charge control unit 23 controls the charging of the battery according to the generated power of the solar cell array or the state of charge of the battery when the solar power is stored in the battery in the charge mode. The charge control unit 23 includes a PWM control unit. As the remaining capacity of the battery increases, the duty ratio of PWM (Pulse Width Modulation) becomes shorter and the battery can be charged at a constant voltage. The PWM duty ratio information is stored in the battery remaining capacity measuring device. The battery remaining capacity measuring device outputs a specific PWM duty ratio of the latest time among the PWM duty ratios stored for a preset time, have. In this embodiment, the charge control section 23 may be substantially the same as the charge control section described in FIG. 1, but is not limited thereto.

The discharge control unit 24 controls discharge for energy stored in the battery in the discharge mode. The discharge control unit 24 can control the discharge of the battery according to the charged state of the battery. For this, the discharge controller 24 according to the present embodiment can control the battery discharge according to any one of preset discharge modes according to the specific PWM duty ratio received from the remaining battery capacity measuring device. That is, the discharge controller 24 extracts or selects an operation mode for maintaining the operating state of the battery for a predetermined period (for example, three days) based on the remaining battery capacity corresponding to the specific PWM duty ratio, The output voltage, output current or output power of the battery can be controlled in a predetermined manner.

The memory system 26 may be connected to the charge controller 23 to store a PWM duty ratio for a predetermined time. The memory system 26 may be implemented with a storage area capable of storing a PWM duty ratio of at least 24 hours. The memory system 26 includes a main memory in the form of a storage medium such as a RAM (Random Access Memory) and a ROM (Read Only Memory) and a long-term memory such as a floppy disk, a hard disk, a tape, a CD- And may include an auxiliary memory in the form of a storage medium. Also, the memory system 26 may include a recording medium, and the recording medium may store data or a program in which the remaining battery capacity measurement method according to the present embodiment or a battery power control method using the method is recorded.

In addition, the memory system 26 not only stores the PWM duty ratio of the charge control section 23, but also can store the remaining battery capacity value corresponding to each value of the PWM duty ratio. Here, the PWM duty ratio value and the remaining battery capacity value may correspond one-to-one in the form of a look-up table or may be stored so that the interval and the interval correspond to each other. At least a portion of such a memory system 26 may correspond to the storage previously described in FIG.

The receiving unit 27 may include a communication unit connected to the battery remaining capacity measuring device and receiving a signal having specific PWM duty ratio information output from the remaining battery capacity measuring device, or an input end for recognizing the received signal. The receiving unit 27 may have an analog-to-digital converter for signal conversion or a digital-analog converter depending on the type of signal (analog, digital, etc.) input from the battery remaining capacity measuring device.

The extracting unit 28 extracts the remaining battery capacity corresponding to the PWM duty ratio information received or recognized through the receiving unit 27. [ The extracting unit 28 can extract the specific battery remaining capacity corresponding to the battery remaining capacity information extracted from the remaining battery capacity values stored in the memory system 26. [ An output signal of the extracting unit 28 including information on the extracted remaining battery capacity may be transmitted to the discharge control unit 24 and used to set an operation mode for the battery discharge.

FIG. 9 is an operation flowchart of the battery power control apparatus of FIG. 7; FIG.

Referring to FIG. 9, the battery power control apparatus according to the present embodiment first receives a signal including a specific PWM duty ratio or a specific PWM duty ratio from the remaining battery capacity measuring apparatus (S91).

The specific PWM duty ratio can be obtained from the battery remaining capacity measuring device described above with reference to Figs. In the present embodiment, the specific PWM duty ratio is a ratio of the PWM duty ratio changing to maintain the battery voltage constant according to the remaining capacity of the battery when the generated power of the solar cell array is charged in the constant voltage mode, The duty ratio of the PWM duty ratio can be matched.

Next, the battery power control device extracts the remaining battery capacity corresponding to the specific PWM duty ratio (S92). The data related to the correspondence between the PWM duty ratio and the remaining battery capacity can be stored in advance in the memory system in a predetermined form.

Next, the battery power control device extracts the battery operation mode corresponding to the extracted remaining battery capacity (S93). The battery operating mode may include a specific discharge mode of the battery or a specific power mode of the battery. The corresponding relationship between the battery remaining capacity and the battery operation mode, or the correspondence between the battery remaining capacity and the type related to the operation of the apparatus (such as the solar streetlight system) can be stored in advance in the memory system in the form of a lookup table or the like.

Next, the battery power control device controls the battery output in accordance with the extracted battery operation mode (S94). That is, the battery power control device can control the lamp lighting in a preset operation mode in order to effectively maintain the lamp lighting operation for the required number of days required by the solar street lamp system or the like, depending on the remaining capacity of the battery.

8 and 9, the battery power control apparatus 20 according to the present embodiment may be configured to charge the battery according to four stages of charging. Here, the four-stage charging step may include bulk charging, PWM absorption charging, equalizing charging, and floating charging.

In the above-described case, the charge control unit 23 controls the switch 22 of the charging and discharging circuit 21 in PWM mode to maintain the voltage of the lead accumulator battery at 14.4 V, Can be adjusted. The switch 22 may be fabricated by applying an FET, a metal oxide semiconductor field effect transistor (MOSFET), or the like. Further, as the battery is nearer to the full charge, the PWM duty ratio is gradually reduced and the amount of current is reduced. When the battery is fully charged, the switch 22 is in an open state with a duty ratio of 0%. On the other hand, when the duty ratio is 100%, it can be determined that the switch 22 operates in the bulk charging step of the first step.

As described above, according to the present embodiment, it is possible to predict the charged state (remaining capacity) of the battery with the PWM duty ratio at the time of constant voltage charging and to control the power consumption of the battery according to the remaining battery capacity, It is possible to apply the lighting section of the lamp differently in the street lamp system and the like.

Table 2 below shows the calculation of the power consumption per day according to the dimming control for each type assuming that a 50 W lamp is used and lights up for 10 hours a day.

As can be seen from Table 2, when simple ON / OFF control is performed without using simple dimming control or dimming irrespective of the remaining capacity of the battery, the consumed electric power of the battery is high and the battery is easily discharged , So the number of days of relief is relatively short. Generally, since the number of days to be provided by a predetermined device may be a case where the remaining capacity of the battery is assumed to be 100%, if the actual device does not control the battery discharge according to the remaining capacity of the battery, It may not operate normally.

In order to prevent such early battery discharge, the battery remaining capacity corresponding to the specific PWM duty ratio is predicted and the battery discharge is controlled in the A type to the E type according to the predicted battery remaining capacity as shown in Table 3 below. can do. For example, when the remaining battery level (SOC) is 395 Wh or more, type A is applied. When the SOC is 370 Wh or more and less than 395 Wh, type B is applied. When the SOC is 330 Wh or less and less than 370 Wh, C type is applied. And the D type is applied when the SOC is less than 330 Wh, and the E type when the SOC is less than 305 Wh.

As described above, in the present embodiment, the battery remaining capacity is reliably predicted based on the PWM duty ratio at the time of battery charging, and smart dimming control is performed for each section or type according to the predicted battery remaining capacity, It is possible to consume battery power in a suitable operation mode, thereby satisfying the conditions required by the solar streetlight system and the like (the number of days to be relieved, for example, three days). The number of days is the number of days required to prevent lamps from being turned off due to over discharge even if the days when the solar cells can not develop due to a rainy season or a cloud are involved.

Meanwhile, the existing dimming control is used simply to reduce the amount of power consumption to increase the number of days of idle time. However, since the remaining capacity of the battery is not considered, the lamp is turned off must do it. However, in this embodiment, the PWM duty ratio is approximated to 0% as the battery reaches the full charge in the PWM charging period, so that the remaining capacity of the battery is predicted with the PWM duty ratio and the dimming control of the LED lamp is performed at that night By differentiating them according to the sections, it is possible to realize an unattended system in an independent solar streetlight.

10 is an exemplary view of a battery operation mode that can be employed in the battery power control apparatus of FIG.

The operation mode of the battery power control apparatus according to the present embodiment is exemplified as applied to the solar streetlight system. The solar streetlight system is a system that charges electric power generated from a solar panel through a battery charge control device and lights an LED lamp by using power stored in the battery at night.

The battery power control device constantly senses the charge voltage of the solar panel and the voltage of the battery in the charge mode to protect the battery from overcharging and overdischarge, and in order to efficiently charge the battery, can do.

The first step is bulk charging, which is a charging method in which the maximum electric current generated in the solar cell is charged to a certain portion of the charging rate or a predetermined voltage V1 when the amount of electricity generated by the solar cell is insufficient. The duty ratio of the switch that operates in accordance with the control of the charge control unit in the bulk charge may be 100%.

The PWM absorption charging in the second stage includes a step of slowly charging and limiting the amount of current until the residual amount of the battery reaches 100% (full charge) after the bulk charging. In general, lead-acid batteries are charged at a constant voltage of 14.4V. At this time, the amount of current to be charged is limited by adjusting the PWM duty ratio in order to maintain the voltage of the battery at 14.4V. That is, as the battery gets closer to full charge, the PWM duty ratio becomes closer to 0%.

Equalize in the third stage is a case where a plurality of batteries are connected in series or in parallel to each other for a long time, the battery condition becomes uneven due to the difference between the self-discharge and the internal resistance of the battery cells inside the battery. This is a charging method that charges at a voltage slightly higher than the normal voltage once every 6 to 7 months. Equal charge can be charged up to 1V per battery based on 12V battery.

Floating in the fourth stage is a charging method that maintains the full charge state by advancing charging at a voltage of a lower level than the PWM charging.

According to this embodiment, the solar power control apparatus and the battery power control apparatus can efficiently charge the battery and maintain the charged state.

According to the above description, the battery power control apparatus according to the present embodiment can control the power consumption of the LED lamp so as to have a longer lighting time and a longer idle time at a limited capacity of the battery. Particularly, in the method of dimming control of the LED lamp, the current amount of the LED lamp driven by the constant current can be differentially controlled according to the remaining capacity of the battery.

For example, a conventional battery power control device controls the brightness of an LED lamp, so it consumes power at 100% brightness immediately after sunset, consumes 70% brightness after 3 hours, 50% It is possible to reduce the power consumption by about 30% compared with the case where only ON / OFF control is performed. In addition, according to the present embodiment, depending on the type (or battery operation mode) And the operation mode of the LED lamp is controlled step by step according to the newly determined type according to the remaining capacity of the battery, which is changed according to the number of days of operation, have.

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 will be understood that various combinations and permutations and applications not illustrated in the embodiments are possible. Therefore, it should be understood that the technical contents related to the modification and application that can be easily derived from the embodiments of the present invention are included in the present invention.

10: Battery remaining capacity measuring device
11:
12:
13:
20: Battery power control device
21: charge / discharge circuit
22: Switch
23:
24:
25: charge / discharge control circuit
26: Memory system
27: Receiver
28:

Claims (9)

A charge controller for charging the battery using pulse width modulation (PWM);
An extracting unit for extracting a specific PWM duty ratio among the PWM duty ratios of the charge control unit;
An estimator for predicting a battery remaining amount corresponding to the specific PWM duty ratio; And
And a discharge control unit for controlling the discharge or consumption power of the battery based on the battery remaining amount predicted by the estimating unit,
Wherein the discharge control unit controls the operation of the lamp connected to the battery so that the solar battery independent power source type device that is coupled with the battery and the lamp and charges the battery with the generated power of the solar battery operates at a predetermined number of days or more, Power control device. The method according to claim 1,
Wherein the discharge control unit determines a battery operation mode corresponding to the predicted battery remaining amount and controls discharge or consumption power of the battery according to a determined battery operation mode. The method of claim 2,
Wherein the discharge control unit controls the lamp connected to the battery to perform dimming control on the lamp according to the determined battery operation mode. delete The method according to claim 1,
And a memory system connected to the charge control unit and storing the PWM duty ratio of the charge control unit for a predetermined time. The method of claim 5,
Wherein the extractor extracts a specific PWM duty ratio most recently stored among the PWM duty ratios. A storage unit connected to a charge control unit for charging the battery using pulse width modulation (PWM) and storing the PWM duty ratio of the charge control unit for a preset time; And
An extracting unit for extracting a specific PWM duty ratio stored at a latest time among the PWM duty ratios stored in the storage unit;
/ RTI >
Wherein the specific PWM duty ratio is used to estimate a specific battery remaining capacity. The method of claim 7,
The charge control unit charges the battery under a constant voltage condition during PWM charging, and the PWM duty ratio is determined based on a battery residual capacity measurement (SOC) that decreases as the state of charge (SOC) of the battery increases to maintain the constant voltage condition Device. The method of claim 7,
Wherein the charge control unit charges the battery with generated power of a solar cell array provided in the solar streetlight system.

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