KR102381582B1 - Energy Management Method and Device for Base Station using Smart Grid - Google Patents

Abstract

A system for controlling charging and discharging of a battery of a base station according to an embodiment of the present invention arranges time zones of the day in the order of a charging unit for charging or discharging a battery and an electricity rate, and at least one of the arranged time zones with the lowest electricity price selecting a time zone as a charging time, selecting one or more time zones with the highest electricity price among the sorted time zones as a discharging time, controlling the charging unit to charge the battery at the selected charging time, and at the selected discharging time By including a control unit for controlling the charging unit to discharge the battery, it is possible to reduce the operating cost of the base station.

Description

Energy Management Method and Device for Base Station using Smart Grid

The present invention relates to a method and apparatus for managing base station energy using a smart grid, and more particularly, to a method and apparatus for utilizing a battery used for a backup purpose in a mobile communication base station for a smart grid energy storage purpose.

The smart grid system is a power distribution system for optimizing energy efficiency by digitizing the power grid. It includes a function of using a battery as a power source when electricity prices are high and charging the battery when electricity prices are low. do.

As an example of the use of the smart grid function, the energy storage system in a building is used to store energy in advance according to DR (Demand Response) when electricity prices are low, and then control to utilize the stored energy during times when electricity prices are high. system as an example.

The following documents contain content on control technologies that reduce electricity costs using smart grid functions.

KR, 10-2013-0092430, Power control device and power control method, Eiichiro Kubota (Sony)

KR, 10-2013-0094925, Energy control method of energy management system, Jeong-in Lee (Electronics and Telecommunications Research Institute, Korea)

The above documents include information on what kind of energy source to use in a distributed power environment in which charging/discharging only considers electricity cost when using a battery, or in a distributed power environment that can use renewable energy.

The energy storage system included in the base station is used only for backup in special situations where the base station power cannot be used, and the smart grid function is not considered. The present invention proposes a method of applying a smart grid function in consideration of the base station operating environment (base station power consumption pattern).

The present invention also provides a charging/discharging control method in consideration of battery characteristics related to battery life.

A method for controlling charging and discharging of a battery of a base station according to an embodiment of the present invention includes the steps of arranging time zones of a day in the order of electricity bills, and selecting one or more time zones with the lowest electricity rates among the sorted time zones as a charging time. selecting one or more time zones with the highest electricity price among the sorted time zones as a discharging time, and charging the battery at the selected charging time and discharging the battery at the selected discharging time characterized in that

In a system for controlling charging and discharging of a battery of a base station according to an embodiment of the present invention, the time of day is arranged in the order of the charging unit for charging or discharging the battery, and the electricity price, and among the sorted time zones, the electricity price is the cheapest Selecting one or more time zones as a charging time, selecting one or more time zones with the highest electricity price among the sorted time zones as a discharging time, controlling the charging unit to charge the battery at the selected charging time, and the selected discharging time It characterized in that it comprises a control unit for controlling to discharge the battery in the charging unit.

It is possible to reduce the operating cost of the base station and extend the life of the base station battery. It is possible to operate the optimal base station energy storage system by providing three different operating methods according to the user's needs.

1 illustrates an energy management system of a base station.
2A, 2B, 2C, and 2D show a method of controlling the system according to the electricity rate priority mode.
3A, 3B, 3C, 3D show a method of controlling a system according to a battery life priority mode.
Figures 4a, 4b, 4c, 4d show a method of controlling the system according to the total cost optimization mode.
5 shows a procedure for selecting a charging time and a discharging time.
6 is a graph comparing battery life, annual electricity cost, and total cost, respectively, when the algorithm of the present invention is applied.
7 is a graph showing power consumption, electricity cost, temperature, and whether charging/discharging is performed by time of day.
8 shows a procedure for performing a smart grid function for a battery of a base station.

In this specification and claims, “comprising” does not mean excluding other elements or acts. In this specification and claims, singular nouns may include plural nouns unless specifically stated otherwise. For example, “battery” may refer to one battery or may include two or more batteries. Also, “time zone” may refer to one time zone or may include two or more time zones. In the present specification and claims, the suffix "part" for a component is given or mixed in consideration of only the ease of writing the specification, and does not have a meaning or role distinct from each other by itself. In this specification and claims, "first, second, and third" are used to distinguish similar elements, and are not necessarily used to describe sequentially or chronologically.

Hereinafter, various embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, only the parts necessary to understand the operation according to the embodiment of the present invention are described, and the description of other parts is simplified or omitted so as not to obscure the gist of the present invention. Here, the features of the present invention are not limited to the above-described examples, and may include a change in the shape of each configuration described below, or even additional functions. In the drawings, the sizes of some elements may be enlarged for illustration, and are not drawn to scale.

The present invention proposes a method of controlling an energy storage device of a base station for smart grid use by specializing in the base station operating environment. In addition, we present a control method for extending the lifespan of a battery (eg, a lithium battery) used as an energy storage device.

The present invention proposes three different charging/discharging control schemes for this purpose. The purpose of each charge/discharge control method is to minimize the electricity cost of the base station, maximize the battery life, or minimize the cost in consideration of both the battery life and the electricity bill.

The present invention controls the charge/discharge of the battery so as not to restrict the normal operation of the base station, and additionally utilizes a control technique that increases the battery temperature by itself to prevent deterioration and damage of the battery at low temperature It is suggested to raise the battery temperature in advance (at an inexpensive time). Through these methods, it is possible to reduce the total cost of ownership (TCO) of the base station.

1 illustrates an energy management system of a base station.

Referring to FIG. 1 , the energy management system 100 of the base station may include the configuration of a charging unit 110 , a battery unit 120 , a sensing unit 130 , a load 140 , and a control unit 150 . .

The charging unit 110 may include an AC/DC rectifier. For example, the charging unit 110 may receive commercial power (eg, 220V AC) 160 to charge the battery unit 120 or supply power to the load 140 . The charging unit 110 may be referred to as a charging/discharging unit.

The battery unit 120 may include a lithium battery that is greatly affected by temperature. The lithium battery may include a lithium ion (Li-ion), lithium polymer (Li-po), or lithium iron phosphate (Li-Fe ₄ ) battery. The battery unit does not include only the lithium battery, and may include other batteries such as lead (Pb) batteries. The battery unit 120 may supply energy to the base station during peak hours of electricity rates and store energy during late-night hours when electricity rates are low.

The sensing unit 130 may be referred to as a battery management system (BMS). The sensing unit 130 may sense a battery state of charge (SOC), a charge/discharge current, a battery cell, an external temperature, and the like, and transmit the sensing result to another unit.

The load 140 may include a base station. The base station includes devices necessary for performing mobile communication with the terminal. The base station may be referred to as a Radio Network Subsystem (RNS), a Base Transceiver Station (BTS), a wireless access point, a nodeB, or an evolved NodeB (eNodeB).

The controller 150 may include an LTE system manager (LSM). The control unit 150 may control the output current of the charging unit 110 based on the information received from the sensing unit 130 and the electricity rate for each time period.

In FIG. 1 , the energy management system 100 of the base station consists of a charging unit 110 , a battery unit 120 , a sensing unit 130 , a load 140 , and a control unit 150 as separate blocks, and each block Although described as performing these different functions, this is only for technical convenience, and each function is not necessarily divided in this way.

The control unit 150 may include a charge/discharge timing control unit that considers the electricity price, a charge/discharge control unit that considers temperature/Depth of Discharge (DOD)/rate of charge or discharge (C-rate), and an idle state control unit. . The control unit 150 may be located inside the load 140 or may correspond to a separate external controller (server). The controller 150 may control the charging and discharging of the charging unit 110 by dividing the electric charge priority mode, the battery life priority mode, and the total cost optimization mode according to the user's selection. The energy storage system of the mobile communication base station and the control system for managing the same are set to operate as auxiliary power (for backup) in a situation where commercial power cannot be supplied. The above three modes may be utilized as a charging and discharging control method for using the base station system for a smart grid purpose.

2A, 2B, 2C, and 2D show a method of controlling the system according to the electricity rate priority mode.

In the electricity cost priority mode, charging and discharging of the battery is controlled in consideration of minimizing the electricity cost. In the case of a base station, the total electricity cost of the base station is calculated by multiplying the real-time electricity rate by the base station power consumption, and within the range allowed by the battery capacity, the battery is discharged when the electricity price is high and the battery is charged when the electricity price is low. can

Referring to FIG. 2A , first, the C-rate of the battery is selected as the maximum value ( 203 ), and the DOD of the battery is selected as the maximum value (eg, 100%) ( 206 ). It is determined whether the expected lifespan of the battery corresponding to the selected DOD is less than a predetermined period (eg, the minimum battery use period of 5 years) ( 209 ). When the expected lifespan of the battery corresponding to the selected DOD is not less than the predetermined period, the DOD is reduced by a predetermined value (eg, 1%) (212), and the expected lifespan of the battery corresponding to the reduced DOD is It is determined again whether it is smaller than the predetermined period. When the expected lifespan of the battery corresponding to the DOD is smaller than the predetermined period, the number of possible charge/discharge per day (for example, 3 times a day) is selected according to the C-rate (215), and the electricity bill is the lowest The battery charge/discharge time (eg, 01:00-02:00, 02:00-03:00, and 06:00-07:00) of the battery is selected as much as possible (218).

In a time other than the selected battery charge/discharge time, the idle state control method is applied to extend the life of the battery ( 221 ). As shown in FIG. 2B , in the idle state, it is first checked whether the temperature of the battery is less than a specific temperature (eg, 15 degrees Celsius) ( 224 ). If the temperature of the battery is less than the specific temperature, it is checked whether the SOC of the battery exceeds a specific value (eg, 90%) ( 227 ). When the SOC of the battery exceeds 90%, the battery is discharged (230). If the SOC of the battery is less than or equal to a specific value, it is determined whether the battery temperature exceeds the specific temperature ( 233 ). When the temperature of the battery is below a specific temperature, discharging is performed, and when the temperature of the battery exceeds the specific temperature, charging is performed. Even when the temperature of the battery is equal to or higher than the specific temperature in step 224, charging or discharging may be performed according to the SOC of the battery.

2c shows the operations of the time selected as the charging time. First, the C-rate of the battery is selected as the maximum value, and the voltage/current is calculated according to the selected C-rate and commanded to the rectifier. When the battery SOC is 100% and the battery is fully charged, the battery idle state is applied (the current command value is 0A) to prevent overcharging of the battery ( 236 ).

2D shows the operations of the time selected as the discharge time. A current command value with a value of 0A is transmitted to the rectifier. Discharging is performed only within the specified SOC range (eg, a value less than or equal to 100%-DOD) (the battery current (I_BAT) and the load current (I_LOAD) are commanded to 0A). If it is outside the range of the determined SOC, the idle state control method may be applied.

3A, 3B, 3C, 3D show a method of controlling a system according to a battery life priority mode.

Battery Life Priority mode controls the charging/discharging of the battery in consideration of maximizing the battery life expectancy. For example, consider the temperature, DOD, and C-rate of the battery.

- Charge/discharge control according to temperature

In consideration of the battery life, it is possible to control not to charge the battery below a specific temperature (eg, 10 degrees Celsius). Also, a charging/discharging method (eg shallow charging/discharging) that can raise the battery's own temperature can be used. Shallow charge/discharge means that the battery's internal temperature is raised by repeating the charging and discharging of the battery in a short cycle, while the DOD of the battery is used very small. /discharge technique. By using shallow charge/discharge, it is possible to control the temperature of the battery to be raised in advance at the shortest time.

- DOD adjustment

If the user sets the desired lifespan, it is possible to control the use of the battery with the maximum DOD that satisfies the corresponding condition. The lower the DOD, the longer the battery life, and the higher the DOD, the shorter the life.

- C-rate adjustment

Battery charging can be controlled with the minimum C-rate within the range that satisfies the battery life. The number of charge/discharge per day is selected based on the C-rate, and the C-rate can be increased if the charging capacity is not satisfied for a set time with the selected C-rate.

Referring to FIG. 3A, first, the life period (eg, 20 years) of the battery desired by the user is input (303), and the initial C-rate value of the battery is selected as the minimum value (eg, 0.1) (306), A DOD corresponding to the input lifetime is selected ( 309 ). Thereafter, it is determined whether the expected life span of the battery corresponding to the selected DOD is smaller than the life span input in step 303 ( 312 ). If the expected life span of the battery corresponding to the selected DOD is not smaller than the life period selected in step 303, the DOD is reduced by a predetermined value (eg, 1%) (315), and the expected life of the battery corresponding to the reduced DOD is It is judged again whether the lifetime is smaller than the lifetime selected in step 303 . When the expected lifespan of the battery corresponding to the DOD is smaller than the lifespan selected in step 303, the charging/discharging time of the battery is selected so that the lifespan of the battery is optimal under the condition of charging/discharging once a day ( 318 ).

In a time other than the selected battery charge/discharge time, the idle state control method is applied to extend the life of the battery ( 321 ). As shown in FIG. 3B , in the idle state, it is first checked whether the temperature of the battery is less than a first specific temperature (eg, 15 degrees Celsius) ( 324 ). When the temperature of the battery is less than the first specific temperature, it is checked whether the SOC of the battery exceeds a specific value (eg, 90%) ( 327 ). When the SOC of the battery exceeds 90%, the battery is discharged (330). When the SOC of the battery is less than or equal to a specific value, it is determined whether the battery temperature exceeds a second specific temperature (eg, 10 degrees Celsius) ( 333 ). When the temperature of the battery is below the second specific temperature, discharging is performed, and when the temperature of the battery exceeds the second specific temperature, charging is performed. Even when the temperature of the battery is equal to or higher than the first specific temperature in step 324 , charging or discharging may be performed according to the SOC of the battery.

3C shows the operations of the time selected as the charging time. First, when charging the battery, whether charging is possible is determined according to the temperature range ( 336 ). That is, charging is not performed when the battery temperature is below a specific temperature. When it is determined that the battery temperature exceeds a specific temperature, the optimal C-rate is selected in consideration of the battery life, and the voltage/current is calculated according to the selected C-rate and commands the rectifier. When the battery SOC is 100% and the battery is fully charged, the battery idle state is applied (the current command value is 0A) to prevent overcharging of the battery (339).

3D shows the operations of the time selected as the discharge time. Discharging is performed only within the specified SOC range (eg, a value less than or equal to 100%-DOD) (the battery current (I_BAT) and the load current (I_LOAD) are commanded to 0A). If it is outside the range of the determined SOC, the idle state control method may be applied.

Figures 4a, 4b, 4c, 4d show a method of controlling the system according to the total cost optimization mode.

In the total cost optimization mode, the charging/discharging of the battery is controlled to minimize the cost by considering both the electricity cost used by the base station and the battery depreciation cost.

As shown in FIG. 4A , first, the initial C-rate value of the battery is selected as the minimum value (eg, 0.1) (403), and the DOD corresponding to the expected lifespan (eg, 10 years) of the battery is selected ( 406). It is determined whether the expected life of the battery corresponding to the selected DOD is less than a predetermined period (eg, 10 years) ( 409 ). When the expected lifespan of the battery corresponding to the selected DOD is not less than the predetermined period, the DOD is reduced by a predetermined value (eg, 1%) (412), and the expected lifespan of the battery corresponding to the reduced DOD is the It is judged again whether it is less than the predetermined period. If the expected life of the battery corresponding to the DOD is smaller than the life period selected in step 403, the charge/discharge time of the battery at which the total cost including the electricity charge and the battery deterioration cost becomes the minimum value under the condition of charging/discharging once a day is selected. (415).

In a time other than the selected battery charging/discharging time, the idle state control method is applied to extend the battery life ( 418 ). As shown in FIG. 4B , in the idle state, it is first checked whether the temperature of the battery is less than a first specific temperature (eg, 15 degrees) ( 421 ). If the temperature of the battery is less than the first specific temperature, it is checked whether the SOC of the battery exceeds a specific value (eg, 90%) ( 424 ). When the SOC of the battery exceeds 90%, the battery is discharged (427). When the SOC of the battery is less than or equal to a specific value, it is determined whether the battery temperature exceeds a second specific temperature (eg, 10 degrees Celsius) ( 430 ). When the temperature of the battery is below the second specific temperature, discharging is performed, and when the temperature of the battery exceeds the second specific temperature, charging is performed. Even when the temperature of the battery is equal to or higher than the first specific temperature in step 324 , charging or discharging may be performed according to the SOC of the battery.

4C shows the operations of the time selected as the charging time. First, when charging the battery, it is determined whether charging is possible according to the temperature range ( 433 ). That is, charging is not performed when the battery temperature is below a specific temperature (eg, 10 degrees Celsius). When it is determined that the battery temperature exceeds a specific temperature, the optimal C-rate is selected in consideration of the battery life, and the voltage/current is calculated according to the selected C-rate and commands the rectifier. When the battery SOC is 100% and the battery is fully charged, the battery idle state is applied (the current command value is 0A) to prevent overcharging of the battery (436).

4D shows the operations of the time selected as the discharge time. Discharging is performed only within the specified SOC range (eg, a value less than or equal to 100%-DOD) (the battery current (I_BAT) and the load current (I_LOAD) are commanded to 0A). If it is outside the range of the determined SOC, the idle state control method may be applied.

5 shows a procedure for selecting a charging time and a discharging time.

One or more time zones in which electricity prices are most expensive for each time zone are selected as the discharge time (510). The discharge amounts of the discharge times selected so far are summed up ( 520 ). It is checked whether discharging is additionally possible based on the battery capacity ( 530 ). If additional discharge is possible, the time zone with the next highest electricity price for each time period is additionally selected as the discharge time.

If discharging is not possible additionally, an amount that can be charged in 1 hour is selected based on the set C-rate ( 540 ). One or more time zones having the lowest electricity rates for each time zone are selected as the charging time ( 550 ). The charging amount of the charging time selected so far is summed up (560). It is determined whether the summed charge amount is smaller than the summed discharge amount (570). If the summed total charge amount is less than the total discharge amount, the charge time is additionally selected. When the summed total charge amount is greater than or equal to the total discharge amount, the selected charge time and discharge time are stored ( 580 ).

In FIG. 5 , the total amount of discharge is calculated before the total amount of charge, but it is also possible to calculate the total amount of discharge later than or simultaneously with the total amount of charge.

Table 1 shows the battery life and cost when the algorithm of the present invention is applied.

mode life expectancy
(year) annual electricity bill
($) Annual savings in electricity bills
($) total cost per year
($) Total cost optimization 10.64 277.9 43.93 300.23 battery life first 19.64 299.7 22.12 313.45 electricity cost priority 5.15 273.0 81.01 317.09

To obtain the results of Table 1, the hourly temperature (four seasons) and real-time electricity rates for a specific day in Tokyo, Japan were applied, and a lithium battery with a maximum base station power consumption of 149W and a battery capacity of 384W was used, and the set DOD was 90%. was calculated under the condition that .

6 is a graph comparing battery life, annual electricity cost, and total cost, respectively, when the algorithm of the present invention is applied.

6 shows the same conditions and results as in Table 1. In the case of the total cost optimization mode, the expected lifetime is about 10 years, and it can be seen that the total cost of 10 years is the lowest among the three modes. In the case of the battery life priority mode, it can be seen that the battery life expectancy is the largest among the three modes. In the case of electricity rate priority mode, it can be seen that the annual electricity cost saving is the highest among the three modes.

7 is a graph showing power consumption, electricity cost, temperature, and whether charging/discharging is performed by time of day.

Referring to FIG. 7 , it can be seen that charging was performed in all three modes from 02:00 to 04:00 when the electricity rate is low, and all three modes were discharged from 12:00 to 13:00 when the electricity rate was high.

Table 2 shows the difference in impedance and life expectancy depending on whether or not the algorithm of the total cost optimization mode is applied.

Algorithm applied battery Algorithm not applied battery initial impedance 121.64 mΩ 122.09 mΩ Impedance after experiment 131.64 mΩ 200.69 mΩ life expectancy 7.93 years 0.98 years

In order to obtain the results of Table 2, charging/discharging experiments were repeated for 2 weeks at -10°C for 3 hours and 15°C for 2 hours.

The expected lifespan was calculated based on the amount of change by measuring the impedance before and after the test of the battery. It can be seen that the expected lifespan differs by about 8 times when the algorithm is applied and not applied.

8 shows a procedure for performing a smart grid function for a battery of a base station.

The LSM may determine a charge/discharge rate (C-rate) of the battery and an expected lifespan of the battery ( 810 ). The LSM may correspond to the controller 150 of FIG. 1 . Although not shown in FIG. 1 , the system of FIG. 1 may further include an input unit capable of detecting a user's input. A user may select an electricity cost priority mode, a battery life priority mode, or a total cost optimization mode through the input unit. In the electricity rate priority mode, the charge/discharge rate is determined as the maximum value, and the determined expected lifespan is compared with the expected lifespan corresponding to the DOD. In the battery life priority mode, the expected lifespan is determined based on a user input. In the total cost optimization mode, the charge/discharge rate and expected lifespan are determined based on a user input. When a charge/discharge rate or an expected lifespan is determined without a user input, it may be determined as a predetermined value. The system may use the smart grid function by any one of the above modes or a mode in which any one of the above modes is partially changed. In this case, mode selection may not be required.

The LSM may sort the time zones of the day in the order of electricity rates ( 820 ). Here, the time zone is exemplified in a unit of one hour, but does not necessarily correspond to this, and may correspond to another unit of time (eg, unit of 20 minutes). Step 820 may be performed prior to or concurrently with step 810 .

The LSM may select one or more time zones with the lowest electricity price from among the sorted time zones as the charging time, and select one or more time zones with the highest electricity price from the sorted time zones as the discharge time ( 830 ). Taking the case of FIG. 7 as an example, the 02:00-03:00 and 03:00-04:00 time zones with the lowest electricity rates are selected as the charging time zones, and the 12:00-13:00 hours with the highest electricity rates are selected as charging time zones. The discharge time zone was selected. 2A, 3A, and 4A , the charging time and the discharging time may be selected based on the determined charging/discharging rate and expected lifespan. The selection of the charging time and the selection of the discharging time may be performed simultaneously, or either one may be performed first. The AC/DC rectifier charges the battery at the selected charging time and discharges the battery at the selected discharging time, under the control of the LSM. Charging and discharging of the battery may use a charge/discharge current of a battery management system (BMS).

According to an embodiment of the present invention, the LSM is an AC/DC rectifier so that the battery is not charged when the temperature of the battery is below a predetermined first temperature (eg, 10 degrees), regardless of whether the current time is the charging time. can control Accordingly, it is possible to prevent damage to the battery. According to another embodiment of the present invention, the LSM performs charging and discharging of the battery when the temperature of the battery is below a predetermined second temperature (for example, 15 degrees Celsius), regardless of whether the current time is the charging time or the discharging time. The AC/DC rectifier can be controlled to repeat (shallow charge/discharge) in short cycles. According to another embodiment of the present invention, the LSM may control the AC/DC rectifier to repeat charging and discharging of the battery in a short cycle (shallow charging/discharging) when the current electricity rate is lower than a predetermined rate.

An uninterruptible power supply (UPS) is a device that enables stable use of electricity even when the electricity supply from a power plant is cut off or a failure occurs. The system of FIG. 1 may be equipped with a UPS function. That is, when the supply of external power to the base station is stopped, power can be supplied to the base station through the battery.

Claims (20)

A method for controlling charging and discharging of a battery of a base station,
checking a control mode set to one of an electricity cost priority mode, a battery life priority mode, or a total cost optimization mode;
determining a C-rate and a depth of discharge of the battery based on the identified control mode;
selecting a charging time and a discharging time of the battery based on the charging/discharging rate and the discharging depth; and
charging the battery at the selected charging time and discharging the battery at the selected discharging time;
The step of selecting the charging time and discharging time of the battery comprises:
arranging time zones of the day in order of electricity price;
selecting one or more time zones with the lowest electricity price as a charging time from among the sorted time zones; and
and selecting, as a discharge time, one or more time zones in which the electricity price is the most expensive from among the sorted time zones. The method of claim 1,
Further comprising the step of determining an expected (expected) lifespan of the battery corresponding to the depth of discharge,
The charging/discharging control method according to claim 1, wherein the charging time and the discharging time are selected based on the determined charging/discharging rate and the expected lifespan. According to claim 1,
When the control mode is set to the electricity rate priority mode, the charge/discharge rate of the battery is determined as a maximum value, and the discharge depth is determined as a maximum value. According to claim 1,
When the control mode is set to the battery life priority mode, the battery charge/discharge control method further comprising the step of obtaining a life period of the battery desired by a user. 5. The method of claim 4,
The battery charge/discharge control method, characterized in that the charge/discharge rate of the battery is determined to be a minimum value, and a different discharge depth is determined based on the obtained life period. The method of claim 1,
Charging or discharging the battery at a time other than the selected charging time and discharging time, based on a temperature and a state of charge (SOC) value of the battery, further comprising the step of charging or discharging the battery. . 7. The method of claim 6,
When the temperature of the battery is less than a predetermined first temperature, further comprising the step of comparing the SOC value of the battery with a specific value,
When the SOC value is equal to or less than the specific value, the battery is discharged when the temperature of the battery is below a predetermined second temperature, and charging is performed when the SOC value exceeds the second temperature. . The method of claim 1 , wherein charging and discharging of the battery are repeated in a short period when the electricity rate is lower than a predetermined rate. The method of claim 1 , wherein the charging and discharging of the battery uses a charging/discharging current of a battery management system (BMS). The method of claim 1 , wherein when the supply of external power to the base station is stopped, power is supplied to the base station through the battery. In the system for controlling the charging and discharging of the battery of the base station,
Check a control mode set to one of an electricity rate priority mode, a battery life priority mode, or a total cost optimization mode, and based on the checked control mode, a C-rate and a depth of discharge of the battery ), and a control unit controlling to select a charging time and a discharging time of the battery based on the charging/discharging rate and the discharging depth; and
a charging unit for charging the battery at the selected charging time or discharging the battery at the selected discharging time;
The control unit aligns time zones of the day in the order of electricity bills, selects one or more time zones with the lowest electricity rates among the sorted time zones as the charging time, and discharges one or more time zones with the highest electricity prices among the sorted time zones A battery charge/discharge control system, characterized in that it controls to be selected by time. 12. The method of claim 11,
The control unit determines an expected (expected) lifespan of the battery corresponding to the depth of discharge,
The charging/discharging control system according to claim 1, wherein the charging time and the discharging time are selected based on the determined charging/discharging rate and the expected lifespan. 12. The method of claim 11,
The battery charge/discharge control system, characterized in that when the control mode is set to the electricity rate priority mode, the charge/discharge rate of the battery is determined as a maximum value and the discharge depth is determined as the maximum value. 12. The method of claim 11,
The battery charge/discharge control system according to claim 1, further comprising an input unit for receiving an input of the life period of the battery from a user. 15. The method of claim 14,
The battery charge/discharge control system, characterized in that when the control mode is set to the battery life priority mode, the charge/discharge rate of the battery is determined as a minimum value and the discharge depth is determined based on the input life period. 12. The method of claim 11,
The charging unit charges or discharges the battery at times other than the selected charging time and the discharging time, based on a temperature and a state of charge (SOC) value of the battery. 17. The method of claim 16,
Further comprising a sensing unit for sensing the temperature of the battery,
When the temperature of the battery sensed by the sensing unit is less than a predetermined first temperature, the control unit is set to compare the SOC value of the battery with a specific value, and
When the SOC value is equal to or less than the specific value, the charging unit discharges the battery when the temperature of the battery is less than or equal to a predetermined second temperature, and performs charging when the temperature of the battery exceeds the second temperature. discharge control system. The battery charge/discharge control system according to claim 11, wherein the charging unit repeats charging and discharging of the battery in a short cycle when the electricity rate is lower than a predetermined rate. The battery charge/discharge control system according to claim 11, wherein the charging and discharging of the battery use a charge/discharge current of a BMS (Battery Management System). The battery charge/discharge control system according to claim 11, wherein when the supply of external power to the base station is stopped, power is supplied to the base station through the battery.

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