KR102311062B1 - Device for providing backup power of advanced metering infrastructure system - Google Patents

Abstract

The present invention relates to a backup power supply device of an advanced metering infrastructure (AMI) system. An objective of the present invention is to enable a normal battery discharge operation by raising the temperature of a battery to 0℃ using heat generated by forcibly operating a cell balancing circuit even when a power failure occurs at the low temperature below zero. For example, the backup power supply device of an AMI system includes a battery unit including a plurality of cells; a battery management unit for charging the battery unit with commercial power supplied to load facilities, wherein the battery management unit is configured to discharge the battery unit when a power failure is detected to supply power to the load facilities and to perform cell balancing when the temperature of the battery unit is less than or equal to the preset temperature or a voltage difference between cells is greater than or equal to a preset value; and a communication unit for transmitting a power outage signal to an AMI server in the event of a power outage.

Description

DEVICE FOR PROVIDING BACKUP POWER OF ADVANCED METERING INFRASTRUCTURE SYSTEM

An embodiment of the present invention relates to a backup power supply device used in an intelligent power metering infrastructure system, and more specifically, using a battery management system including a backup power function from a battery even in a blackout state where AC commercial power is not supplied. It relates to a backup power supply that can supply or cut off power to a load facility.

The intelligent power metering infrastructure system (AMI (Advanced Metering Infrastructure) System) remotely reads the usage of various meters installed in consumers who consume energy, such as electricity, gas, water, hot water, and heat, while automatically reading the information from the upper system. It refers to a device for a two-way communication infrastructure that collects, analyzes, and processes data and provides it back to consumers.

In such a typical AMI system, the amount of usage of the electronic watt-hour meter installed on the consumer side is collected from a data concentration unit (DCU) using a slave modem and a master modem for AMI, and then transmitted to the AMI server.

In such a case (DCU, power information and file management do not work normally due to damage to each element or loss of stored data when power failure occurs.

To this end, in the existing system, a battery and a battery management system are installed in the event of a power outage, and the battery management system uses a heating heater for internal heat generation at low temperatures, but this increases the overall volume of the device and prevents cell balancing when using power. factor that can cause problems.

Laid-open Patent Publication No. 10-2017-0048991 (published date: May 10, 2017) Laid-open Patent Publication No. 10-2015-0071194 (published date: June 26, 2015) Registered Patent Publication No. 10-1551088 (Registration Date: September 01, 2015)

An embodiment of the present invention is an intelligent power metering infrastructure that enables normal battery discharging operation by raising the temperature of the battery to 0°C using the heat generated by forcibly operating the cell balancing circuit even if a blackout occurs at a low temperature below zero. Provides a backup power supply for the system.

A backup power supply of an AMI according to an embodiment of the present invention includes: a battery unit including a plurality of cells; When the battery unit is charged with commercial power supplied to the load facility, the battery unit is discharged when a power failure is detected to supply power to the load facility, and the temperature of the battery unit is below a preset temperature or when the voltage difference between cells is greater than or equal to a preset value a battery manager performing cell balancing; and a communication unit that transmits a power outage occurrence signal to an AMI (Advanced Metering Infrastructure) server when a power outage occurs.

In addition, the battery management unit, a relay switch unit for receiving commercial power or power from the battery unit and transferring it to a load facility; AC/DC converter for receiving commercial power and converting it into direct current; a DC/AC inverter that converts the DC power supplied from the battery unit into AC and transmits the relay switch unit; a temperature sensor for measuring the temperature of the battery unit; a cell balancing circuit unit performing cell balancing of the battery unit; a cell voltage difference measuring unit measuring a voltage difference between cells of the battery unit; and charging the DC power converted through the AC/DC converter to the battery unit, and controlling the DC power of the battery unit to be transferred to the relay switch unit through the DC/AC inverter when a power failure occurs, and measuring the temperature sensor When the temperature value is equal to or less than a preset reference temperature value or when the voltage difference measured by the cell voltage difference measuring unit is equal to or greater than a preset reference voltage difference, a battery controller configured to control the cell balancing circuit unit to operate.

In addition, the battery control unit operates in a low-temperature mode for a pre-stored period and when the low-temperature mode operates, compares the measured temperature value with the reference temperature value, and when the measured temperature value is equal to or less than the reference temperature value, the cell balancing circuit unit is controlled to operate, and when the measured temperature value exceeds the reference temperature value by comparing the measured temperature value with the reference temperature value, the cell voltage difference measuring unit is controlled to operate to obtain and obtain the measured voltage difference The measured voltage difference is compared with the reference voltage difference, and when the measured voltage difference is greater than or equal to the reference voltage difference, the cell balancing circuit unit is controlled to operate, and the measured voltage difference is compared with the reference voltage difference If it is less than the reference voltage difference, the operation of the low temperature mode may be restarted after a preset time.

In addition, the cell balancing circuit unit may be installed inside the battery unit to increase the temperature of the battery unit using heat generated by the cell balancing operation.

In addition, each cell of the battery unit may include a lithium iron phosphate (LiFePO ₄ ) secondary battery.

According to the present invention, an intelligent power metering infrastructure system that enables normal battery discharge operation by raising the temperature of the battery to 0°C using the heat generated by forcibly operating the cell balancing circuit even when a power failure occurs at a low temperature below zero. A backup power supply may be provided.

1 is a block diagram showing the overall configuration of a backup power supply of an AMI according to an embodiment of the present invention.
2 is a block diagram illustrating a detailed configuration and connection relationship of a battery management unit according to an embodiment of the present invention.
3 is a flowchart illustrating an operation of a battery controller according to an embodiment of the present invention.
Figure 4 is a front view of the backup power supply of the AMI according to an embodiment of the present invention.
5 is a side view of a backup power supply of an AMI according to an embodiment of the present invention.
6 is a side perspective view of a backup power supply of an AMI according to an embodiment of the present invention.

Terms used in this specification will be briefly described, and the present invention will be described in detail.

The terms used in the present invention have been selected as currently widely used general terms as possible while considering the functions in the present invention, but these may vary depending on the intention or precedent of a person skilled in the art, the emergence of new technology, and the like. In addition, in a specific case, there is a term arbitrarily selected by the applicant, and in this case, the meaning will be described in detail in the description of the corresponding invention. Therefore, the term used in the present invention should be defined based on the meaning of the term and the overall content of the present invention, rather than the name of a simple term.

When a part "includes" a certain element throughout the specification, this means that other elements may be further included, rather than excluding other elements, unless otherwise stated. In addition, terms such as "...unit" and "module" described in the specification mean a unit that processes at least one function or operation, which may be implemented as hardware or software, or a combination of hardware and software. .

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those of ordinary skill in the art can easily carry out the embodiments of the present invention. However, the present invention may be embodied in several different forms and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

1 is a block diagram showing the overall configuration of a backup power supply device of an AMI according to an embodiment of the present invention, FIG. 2 is a block diagram showing a detailed configuration and connection relationship of a battery management unit according to an embodiment of the present invention, FIG. 3 is a flowchart for explaining the operation of the battery controller according to an embodiment of the present invention.

Referring to FIG. 1 , the AMI backup power supply device 1000 according to an embodiment of the present invention may include at least one of a battery unit 100 , a battery management unit 200 , and a communication unit 300 .

The battery unit 100 may include a plurality of battery cells 110, and each battery cell 110 may be connected in a suitable form for supplying AMI backup power in series, parallel, or series/parallel mixed method. have.

The battery cell 110 may include a lithium iron phosphate (LiFePO ₄ ) secondary battery. These lithium iron phosphate (LiFePO ₄ ) secondary batteries can be recharged more than 1,000 times even after discharging up to 90% of their total capacity, and have a lifespan three times longer than that of conventional lead-acid batteries, and even after charging and discharging more than 1,000 times, more than 80% of the existing capacity it is possible to maintain Conventional lithium ion and lithium polymer batteries may cause rapid temperature rise and explosion during overcharging and overdischarging, but lithium iron phosphate batteries do not explode during overdischarge and overcharge and are relatively safe as they are only damaged internally. .

The battery management unit 200 charges the battery unit with commercial power supplied to the load facility, discharges the battery unit when a power failure is detected to supply power to the load facility, and the temperature of the battery unit is below a preset temperature or a cell Cell balancing is performed when the voltage difference between the two is greater than or equal to a preset value.

To this end, the battery management unit 200 includes a relay switch unit 210 , an AC/DC converter 220 , a DC/AC inverter 230 , a temperature sensor 240 , and a cell balancing circuit unit 250 as shown in FIG. 2 . , at least one of a cell voltage difference measurement unit 260 and a battery control unit 270 .

The relay switch unit 210 may receive external commercial power or power from the battery unit 100 and transmit it to a load facility. The relay switch unit 210 operates to transmit external commercial power to the load equipment according to the first control signal of the battery control unit 270, or when a power outage occurs, DC / according to the second control signal of the battery control unit 270 AC power supplied from the battery unit 100 through the AC inverter 230 may be connected to be delivered to a load facility.

The AC/DC converter 220 receives some power from external commercial power under the control of the battery control unit 270 , converts it into direct current, and then transmits it to the battery unit 100 so that the battery unit 100 is charged. can do.

The DC/AC inverter 230 converts the DC power supplied from the battery unit 100 into AC and transmits the relay switch unit 210 , and is supplied from the battery unit 100 through the relay switch unit 210 . It can play a role as a means of conversion and mediation that provides AC power to load equipment.

The temperature sensor 240 may measure the internal temperature of the battery unit 100 , and the measurement temperature range is preferably -50°C to 100°C, but the specific temperature range is not limited.

The cell balancing circuit unit 250 may perform cell balancing of the battery unit 100 . The cell balancing circuit unit 250 may be implemented to operate in at least one of a passive method and an active method. Here, the passive type is a method of balancing the battery cells by consuming the charge of the overcharged battery cell through individual resistors, and the active type is a method of supplying more current to the undercharged battery cells with an individual charger to provide more current between the battery cells. A way to balance the When using a battery with a relatively small capacity, such as an intelligent power metering infrastructure system, it is preferable to adopt a passive method, and in particular, heat generated through power consumption using individual resistors is reduced to approximately -20°C in the battery unit 100 It is more preferable to adopt a passive method because it is suitable for raising the internal temperature of the

The cell voltage difference measurement unit 260 may measure a voltage difference between each cell of the battery unit 100 , and transmit the measured voltage difference value to the battery control unit 270 .

The battery control unit 270 controls the AC/DC converter 200 to charge the DC power converted through the AC/DC converter 220 in the battery unit 100, and when a power failure occurs, the battery unit 100 The DC/AC inverter 230 is controlled to transfer the DC power charged to the DC/AC inverter 230 to the relay switch unit 210 through the DC/AC inverter 230, and the AC power provided through the DC/AC inverter 230 is loaded. The relay switch unit 210 may be controlled to be transmitted to the facility.

When the measured temperature value of the temperature sensor 240 is less than or equal to a preset reference temperature value, or when the measured voltage difference of the cell voltage difference measuring unit 260 is greater than or equal to a preset reference voltage difference, the cell balancing circuit unit ( 250) can be controlled to perform a cell balancing operation.

More specifically, as shown in FIG. 3 , the battery control unit 270 operates in the low temperature mode for a pre-stored period (winter season). During this low temperature mode operation, the measured temperature value received from the temperature sensor 240 and the preset When the measured temperature value is less than or equal to the reference temperature value by comparing the reference temperature value (approximately -20 ° C), by controlling the cell balancing circuit unit 250 so that the cell balancing operation of the cell balancing circuit unit 250 is forcibly performed, the cell balancing circuit unit ( 250), the internal temperature of the battery unit 100 is raised to approximately 0° C. due to the heat generated by the cell balancing operation, so that the backup power supply 1000 of the AMI of the present embodiment operates normally.

In addition, the battery control unit 270 compares the measured temperature value received from the temperature sensor 240 with a preset reference temperature value (approximately -20°C), and when the measured temperature value exceeds the reference temperature value, the cell voltage difference is measured After obtaining the measured voltage difference by controlling the unit 250 to operate, compare the obtained measured voltage difference with a preset reference voltage difference (approximately 30 mV), and if the measured voltage difference is greater than or equal to the reference voltage difference, the cell balancing circuit unit 250 By controlling the cell balancing circuit unit 250 so that the cell balancing operation of The backup power supply 1000 of the AMI of the embodiment is to operate normally.

In addition, as a result of comparison between the measured voltage difference received from the cell voltage difference measuring unit 250 and a preset reference voltage difference (approximately 30 mV), the battery controller 270 determines that the measured voltage difference is less than the reference voltage difference for a preset time (approximately 30 mV). 1 hour to 2 hours) after which the low-temperature mode operation can be resumed.

The communication unit 300, when a power outage occurs, transmits a power outage occurrence signal to an external AMI (Advanced Metering Infrastructure) server to report the power outage occurrence. In addition to this purpose, information such as the charge/discharge state of the battery unit 100 can be reported, and the AMI server can be connected for remote control. The communication unit 300 may apply an RS-485 communication method, and the specific configuration of the communication unit 300 is not limited in this embodiment.

Figure 4 is a front view of the backup power supply of the AMI according to an embodiment of the present invention, Figure 5 is a side view of the backup power supply of the AMI according to an embodiment of the present invention, Figure 6 is according to an embodiment of the present invention A side perspective view of the AMI's backup power supply.

4 to 6, the backup power supply 100 of the AMI according to an embodiment of the present invention includes a case 400, a power switch unit 500, a power terminal unit 600, and a battery remaining indicator lamp unit ( 700 ) and at least one of the communication cable terminal unit 800 .

The case 400 is a means for embedding the battery unit 100, the battery management unit 200, and the communication unit 300 described above and may be made of a substantially rectangular parallelepiped, but in this embodiment, the structure of the case 300 is It is not limited together, and can be implemented in various forms. The case 300 may be made of a double metal panel, and may include a nano-ceramic coating layer coated to a specific thickness on the inner surface of the double metal panel for insulation and heat insulation, and a heat insulating material filled between the nano-ceramic coating layer. The nano-ceramic coating layer has ultra-fine pores in a vacuum state and may be composed of nano-ceramics in which nano-ceramic ball particles and acrylic organic compounds are mixed with air injected into the ultra-fine pores, and the thickness of the nano-ceramic coating layer is 0.1 to 6 mm. It may be made, and the insulating material may include glass fiber, hard urethane or rock wool. Such a nano-ceramic coating layer insulates heat generated inside the case 400 and shields external heat, thereby minimizing damage due to freezing or high heat of a circuit or battery provided inside the case 400. .

The power switch unit 500 may be provided on the front of the case 400 to turn on/off the operation of the backup power supply 1000 of the AMI.

The power terminal unit 600 is a terminal terminal for receiving external power or supplying power to the outside.

The remaining battery indicator lamp unit 700 is a means for displaying the remaining amount of the battery unit 100, and the green lamp on the left turns on when the remaining battery level is 10% or more, and the red lamp on the right side indicates the remaining battery level of 10%. If it is less than, it can light.

The communication cable terminal unit 800 is connected to the internal communication unit 300 and may be connected to an external AMI server through a communication cable.

On the other hand, the cell balancing circuit unit 250 may be installed inside the battery unit 100 as shown in FIG. 6 to effectively increase the temperature of the battery unit 100 by using the heat generated by the cell balancing operation. have. More specifically, the cell balancing circuit unit 250 is installed at a position in direct contact with the battery cells 110 , and may be disposed between the battery cells 110 . It is possible to effectively raise the internal temperature of the battery cell 110 to 0°C.

As the conventional battery management system uses a heating heater for internal heat generation at low temperatures, it not only adds to the overall volume of the device, but also acts as a factor that can cause problems with cell balancing when using power. In the present embodiment, even if a power failure occurs at a low temperature below zero, the temperature of the battery is raised to 0° C. by using the heat generated by forcibly operating the cell balancing circuit without applying a heating heater, thereby enabling a normal battery discharge operation.

What has been described above is only one embodiment for implementing the backup power supply of the AMI according to the present invention, and the present invention is not limited to the above embodiment, and as claimed in the claims below, the present invention Without departing from the gist, it will be said that the technical spirit of the present invention exists to the extent that various modifications can be made by anyone with ordinary knowledge in the field to which the invention pertains.

1000: AMI's backup power supply
100: battery unit
110: battery cell
200: battery management unit
210: relay switch unit
220: AC/DC converter
230: DC/AC inverter
240: temperature sensor
250: cell balancing circuit unit
260: cell voltage difference measuring unit
270: battery control
300: communication department
400: case
500: power switch unit
600: power terminal unit
700: battery remaining indicator lamp unit
800: communication cable terminal part

Claims (5)

a battery unit including a plurality of cells;
When the battery unit is charged with commercial power supplied to the load facility, the battery unit is discharged when a power outage is detected to supply power to the load facility, and the temperature of the battery unit is below a preset temperature or when the voltage difference between cells is greater than or equal to a preset value a battery manager performing cell balancing; and
Including a communication unit that transmits a power outage signal to an AMI (Advanced Metering Infrastructure) server when a power outage occurs,
The battery management unit,
a relay switch unit receiving commercial power or power from the battery unit and transferring it to a load facility;
AC/DC converter for receiving commercial power and converting it into direct current;
a DC/AC inverter that converts the DC power supplied from the battery unit into AC and transmits the relay switch unit;
a temperature sensor for measuring the temperature of the battery unit;
a cell balancing circuit unit performing cell balancing of the battery unit;
a cell voltage difference measuring unit measuring a voltage difference between cells of the battery unit; and
The DC power converted through the AC/DC converter is charged to the battery unit, and when a power outage occurs, the DC power of the battery unit is controlled to be transferred to the relay switch unit through the DC/AC inverter, and the temperature measured by the temperature sensor When the value is equal to or less than a preset reference temperature value, or when the voltage difference measured by the cell voltage difference measuring unit is equal to or greater than a preset reference voltage difference, a battery control unit for controlling the cell balancing circuit unit to operate;
The battery control unit,
When the low-temperature mode is operated for a pre-stored period and the low-temperature mode is operated, the measured temperature value is compared with the reference temperature value, and when the measured temperature value is equal to or less than the reference temperature value, the cell balancing circuit unit is controlled to operate, When the measured temperature value exceeds the reference temperature value by comparing the measured temperature value with the reference temperature value, the cell voltage difference measuring unit is controlled to operate to obtain the measured voltage difference, and the obtained measured voltage difference and the If the measured voltage difference is greater than or equal to the reference voltage difference by comparing the reference voltage difference, the cell balancing circuit unit is controlled to operate, and by comparing the measured voltage difference with the reference voltage difference, if the measured voltage difference is less than the reference voltage difference, Backup power supply of AMI, characterized in that restarting the operation of the low temperature mode after a preset time.
delete delete According to claim 1,
The cell balancing circuit unit,
The backup power supply of the AMI, characterized in that installed inside the battery unit to increase the temperature of the battery unit using the heat generated by the cell balancing operation.
According to claim 1,
Each cell of the battery unit is a lithium iron phosphate (LiFePO ₄ ) Backup power supply of the AMI, characterized in that it comprises a secondary battery.

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