KR20230011128A - Smart power meter - Google Patents

Abstract

According to the present invention, a smart power meter comprises: a measuring unit measuring a power consumption; a processing unit controlling the smart power meter; and a peripheral device interface unit interfacing peripheral devices of the smart power meter. The peripheral device interface unit includes: a peripheral device interface interfacing the processing unit and the peripheral device interface; a device control unit controlling the peripheral devices connected to the peripheral device interface; a communication unit; and a time control unit. The peripheral devices include wired and wireless communication peripheral devices. The smart power meter allows a user to control the smart power meter through network. Therefore, the power consumption at home can be controlled from a remote place.

Description

Smart power meter {SMART POWER METER}

The present invention relates to a smart watt-hour meter, and more specifically, charges for each time slot and real-time power usage charges can be checked, a user can remotely check domestic power consumption, and remotely control the smart watt-hour meter to save domestic power. It is about a smart power meter that can be controlled.

As an intelligent power grid, the smart grid is a complex system that dramatically contributes to improving energy efficiency through real-time interaction between producers and consumers in the existing supplier-centered unilateral power market. Smart Grid is inducing the participation of various market participants as it is expanding not only to the existing power fields of power generation, transmission and distribution, but also to telecommunications, new and renewable energy, electric vehicles, home appliances, and construction industries.

Since 2000, the direction of electricity meter has been changed from mechanical type to electronic type for the purpose of improving the accuracy of metering. Early electronic watt-hour meters, like mechanical watt-hour meters, were centered on accurate metering and measurement of basic power consumption, but with the development of electronic communication technology, remote meter reading technology is gradually being developed.

As the functional advancement of electronic watt-hour meters is promoted, centered on Korea Electric Power Corporation (KEPCO), it becomes possible to analyze the amount of electricity used by consumers over time in simple AMR (Automatic Meter Reading), and personal privacy such as consumer power usage patterns from used power information. As it is treated as related information, the internal information (power usage information) of the watt-hour meter is treated as personal information related to personal privacy.

In the flow of such technology, multifunctional smart devices that can charge for each time of use and check real-time power usage rates, allow users to remotely check power consumption in the home, and remotely control the smart watt-hour meter to control the power in the home. A power meter is required.

There is a problem to be solved by an electronic watt-hour meter, and the present invention is to solve this technical problem. The present invention is to provide a smart watt-hour meter that enables charging of power usage time slots, can check power usage charges that change in real time, enables remote meter reading regardless of communication environment, and has expanded functions through firmware update. It is for

The technical problems to be achieved by the present invention are not limited to the above-mentioned technical problems, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description of the present invention. .

The smart watt-hour meter of the present invention includes a metering unit that measures the amount of power consumed, a processing unit that controls the smart watt-hour meter, and a peripheral device interface unit that interfaces the peripheral device of the smart watt-hour meter. The peripheral device interface interfaces the processing unit and the peripheral device interface. A peripheral device interface for controlling peripheral devices, a device controller for controlling peripheral devices connected to the peripheral device interface, a communication controller, and a time controller. You can control the electricity meter.

The present invention has been made to solve the above-mentioned problems of the prior art, and is a smart watt-hour meter, the smart watt-hour meter, a metering unit for measuring the amount of power consumed; a processing unit controlling the smart watt-hour meter; and a peripheral device interface unit that interfaces the peripheral device of the smart watt-hour meter, wherein the peripheral device interface unit controls a peripheral device interface that interfaces the processing unit and the peripheral device interface and peripheral devices connected to the peripheral device interface. A device control unit, a communication control unit, and a time control unit are provided, the peripheral devices include wired and wireless communication peripheral devices, and the smart watt-hour meter allows a user to control the smart watt-hour meter through a network. Provides a smart watt-hour meter.

In the present invention, it is preferable that the smart watt-hour meter measures the amount of power consumed for each usage time and usage date, and separately measures the amount for each rate.

In the present invention, the smart watt-hour meter further includes a plurality of current sensors and one or more voltage sensors, and the metering unit preferably measures reactive power, apparent power, voltage, frequency, power factor, and total harmonic distortion.

In the present invention, the smart watt-hour meter further includes a plurality of current sensors and one or more voltage sensors, and the metering unit preferably measures reactive power, apparent power, voltage, frequency, power factor, and total harmonic distortion.

In the present invention, the peripheral device further includes a latch relay connected to the device in the user's premises, and the user remotely controls the latch relay included in the smart watt-hour meter to supply or cut off power to the device in the premises. desirable.

In the present invention, it is preferable that the wired and wireless communication peripheral devices receive the firmware of the smart watt-hour meter from a network, and the processing unit updates the firmware of the smart watt-hour meter with the firmware received through a bootloader.

In the present invention, the smart watt-hour meter further includes a security unit, and the security unit preferably includes an encryption engine that encrypts and decrypts transmitted and received data according to an AES-128 security algorithm.

In the present invention, it is preferable that the smart watt-hour meter transmits the amount of power consumed on a predetermined date to a power supplier.

In the present invention, the metering unit includes an analog to digital converter (ADC) that converts a value measured using a current sensor and a voltage sensor into digital, and the analog to digital converter performs 3-fold oversampling it is desirable

In the present invention, the analog-to-digital converter is preferably implemented as a programmable gate array (PGA).

According to the smart watt-hour meter according to the present invention, the advantage of being able to check the real-time power usage fee and charge for each time period is provided. Furthermore, according to the present embodiment, the user can remotely check power consumption in the home and control the home power by remotely controlling the smart watt-hour meter.

The effects of the present invention are not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

1 is an exemplary view showing the front of a smart watt-hour meter 100 according to this embodiment in a state covered with a cover.
2 is a diagram illustrating an internal design of the smart watt-hour meter 100 with the cover removed.
3 is a block diagram illustrating the structure of a smart watt-hour meter 100 according to this embodiment.
FIG. 4(a) is an exemplary diagram illustrating a process of transmitting the amount of electricity measured to a provider through a wired and wireless communication peripheral device (Comm) included in the smart watt-hour meter 100 and a network.
4(b) is an exemplary diagram schematically illustrating a process of receiving firmware necessary for driving the smart electricity meter 100 from a supplier through a network;
4(c) is an exemplary diagram schematically illustrating a process in which a user remotely controls the smart watt-hour meter 100 through a network.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms or words used in this specification and claims should not be construed as being limited to the usual or dictionary meaning, and the inventor appropriately uses the concept of the term in order to explain his/her invention in the best way. It should be interpreted as a meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined. Therefore, the embodiments described in this specification and the configurations shown in the drawings are only the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention, so various alternatives can be made at the time of this application. It should be understood that there may be equivalents and variations.

1 is a view showing the front of the smart watt-hour meter 100 according to this embodiment in a state covered with a cover, and FIG. 2 is a diagram illustrating an internal design of the smart watt-hour meter 100 with the cover removed. . Referring to FIGS. 1 and 2, the smart watt-hour meter 100 includes a display unit 110 that displays measurement values measured by the smart watt-hour meter 100, set values of the smart watt-hour meter 100, input values, and output values. do. In one embodiment, the display unit 110 may be a liquid crystal display device.

The alarm unit 112 may notify an operating state and a failure state of the smart watt-hour meter 100, or display a case in which the amount of power used is less than a preset value or exceeds a preset value. In one embodiment, the alarm unit 112 may include a plurality of light emitting elements.

The user sets the operation of the smart watt-hour meter 100 through the button unit 120. As an embodiment, the user can set the wireless communication access AP name of the smart watt-hour meter 100, a password, and a power measurement method such as single-phase two-wire or three-phase four-wire through the button unit 120.

As illustrated in FIGS. 1 and 2 , the smart watt-hour meter 100 of this embodiment may be housed in a housing H including a cover and have a waterproof structure. For example, the smart watt-hour meter 100 of this embodiment can satisfy IP54 waterproof regulations and can be installed and used outside the user's home. The smart watt-hour meter 100 according to this embodiment may be made of a PC (Polycarbonate) material having strong impact resistance, abrasion resistance, and light resistance.

Referring to FIG. 2, the cable insertion part 130 of the present invention contains 15 to 40% by weight of silicone resin, 12 to 30% by weight of triphenyl phosphate, 5 to 20% by weight of decabromodiphenylethane, It may be coated with a coating composition containing 0.5 to 5% by weight of 3-mercaptopropyl methyldimethoxysilane as a silane coupling agent, 1 to 7% by weight of one or more of the group consisting of magnesium carbonate and calcium carbonate, and the remainder solvent. .

If the cable insertion part 130 is configured with such a coating composition, heat resistance and high temperature and high humidity resistance in the housing of the smart watt-hour meter can be improved, thereby helping to improve operational stability and long lifespan of the smart watt-hour meter.

Meanwhile, referring to FIG. 1 , a corrosion-resistant and wear-resistant coating agent may be applied to the housing H of the smart watt-hour meter. That is, with respect to 100 parts by weight of PC (Polycarbonate) forming a smart watt-hour meter, powder containing 24.6 to 52.8 parts by weight of zirconium, 37.2 to 72.4 parts by weight of niobium, and 1.5 to 3.0 parts by weight of scandium or yttrium is sprayed. Thus, a corrosion-resistant and wear-resistant coating agent can be applied.

By applying such a corrosion-resistant and wear-resistant coating agent, durability, corrosion resistance, friction characteristics, wear characteristics, etc. of the housing of the smart watt-hour meter can be improved, so that the operation stability and longevity of the smart watt-hour meter can be promoted.

3 is a block diagram illustrating the structure of the smart watt-hour meter 100 according to this embodiment. Referring to FIG. 3, the smart watt-hour meter 100 includes a processing unit 220 that controls the smart watt-hour meter 100, a metering unit 210 that measures the amount of power consumed through a cable inserted into the cable insertion unit 130, and , Encryption unit 230 including an encryption engine 232 that encrypts transmitted and received data, inputs and outputs data such as the amount of power currently used, the accumulated amount of power used so far, the user's set value, firmware, and rates so far A peripheral device interface unit 300 that interfaces with peripheral devices such as one or more current sensors, voltage sensors, power supplies, latch relays, auxiliary terminals, and wired and wireless communication peripherals. It includes devices (Comm.) and the like.

The metering unit 210 includes a current sensor, an analog to digital converter (ADC) 212 that converts a value measured using a voltage sensor into a digital value, and a digital signal processor that calculates and processes the converted digital value. (DSP, digital signal processor, 214) is included.

In one embodiment, the analog-to-digital converter 212 is implemented as a programmable gate array (PGA), and may be implemented as an analog-to-digital converter capable of 3-fold oversampling. In addition, the analog-to-digital converter 212 receives the reference voltage Vref and the measured temperature value. Accordingly, deviation of values measured by the current sensor and the voltage sensor due to the temperature and the reference voltage can be reduced.

Furthermore, by performing 3-fold oversampling, it is possible to measure the error rate of 2% of reactive power measured by a conventional watt-hour meter and the error rate of active power of 1% to 1% of error rate of reactive power and 0.5% of active power error rate. Compared to this, it has improved error rate characteristics.

Furthermore, the conventional watt-hour meter could measure only active power, but the metering unit 210 of the smart watt-hour meter 100 according to this embodiment is connected to a plurality of current sensors and a plurality of voltage sensors to measure reactive power, apparent power, Measurement of voltage, frequency and power factor is possible.

The processing unit 220 includes a processor 222, a memory 224, a high-speed data transmission unit 226, and an interface controller 228, and measures the amount of power measured by the metering unit 210 through the interface 310. Provided, or process the value provided through the interface 310. In addition, the processing unit 220 controls the operation of the smart watt-hour meter 100 and controls the smart watt-hour meter 100 as set by the user through the button unit 120.

In one embodiment, the processor 222 may be a general-purpose microprocessing unit (MCU) capable of general-purpose calculation and processing, and in this embodiment, the processor 222 may be a Cortex M3-based MCU.

In one embodiment, the memory 224 may be a random access memory (RAM), and may store commands and operation results necessary for processing. For example, the storage capacity of the memory 224 may be 128 KB. In the illustrated embodiment, the processing unit 220 may be connected to an external memory (Ext. memory) to expand the storage capacity.

In one embodiment, processing unit 220 may include a high-speed data transmission unit 226 . The high-speed data transmission unit 226 is a direct memory access controller (DMAC) and is used with the peripheral device interface 310 and the peripheral devices 320, 321, ..., 329. For example, the high-speed data transmission unit 226, DMAC, performs data transmission through four data transmission channels. In one embodiment, the DMAC high-speed data transmission unit 226 may be used in conjunction with a timer and high-speed pulse output for high-speed data transmission with peripheral devices.

Data transmission and reception between the processor 222, the memory 224, and the high-speed data transmission unit 226 is performed according to the high-speed data bus, AHB bus (Advanced high-performance bus) interface standard. The AHB bus operates at a high system clock and enables data transmission and reception between the processor 222, the memory 224, and the high-speed data transmission unit 226 with high throughput.

The interface controller 228 includes a system controller 3200 included in the device control unit 320, a display controller 32010, an I2C communication controller 3212 included in the communication control unit 321, and an SPI interface controller (Serial periphral device interface, 3214), UART communication controller 3216, CAN communication controller 3218, and RTC 326 and timer 327 included in time controller 322 APB bus used in peripheral devices with low power consumption such as processor 222, the memory 224 and the high-speed data transfer unit 226 are mutually interfaced with the AHB bus, which is a high-speed data bus. Therefore, the data transfer throughput between the processor 222, memory 224 and high-speed data transfer unit 226 is not reduced, and the peripheral devices 320, 321, ..., 329 operate with low power, To interface with the processing unit 220.

The encryption unit 230 includes an encryption engine 232 that encrypts transmitted and received data. The encryption engine 232 may encrypt and protect transmitted/received data according to, for example, an AES-128 security algorithm.

The peripheral device interface unit 300 includes a peripheral device interface (Peri. Interface, 310), a device controller 320 that controls the smart watt-hour meter and peripheral devices, a communication controller 321 that controls communication between the smart watt-hour meter and peripheral devices, and smart and a time controller 322 that sets and shares the system clock of the time of the watt-hour meter system and the peripheral device. For example, the system controller 3200 and the display controller 3201 interface with the processing unit 220 through the peripheral device interface 310 to transmit and receive data. The system controller 3200 controls peripheral devices such as a smart power meter and/or a communication peripheral device (Comm.). The display controller 3201 controls the display unit 110 to display information to the user.

The communication control unit 321 includes an I2C communication controller 3212, an SPI communication controller 3214, a UART communication controller 3216, and a CAN communication controller 3218, and peripheral devices and peripheral devices connected through these communication controllers. Data is transmitted and received through the interface unit 300 .

For example, the communication control unit 321 may be connected to a wired and wireless communication peripheral device (Comm.) to receive driving firmware of the smart watt-hour meter 100 and perform an update. As another example, the communication control unit 321 may be connected to a wired and wireless communication peripheral device (Comm.) and transmit the amount of power measured by the smart watt-hour meter 100 to the power supplier.

The time controller 322 of the peripheral device interface unit 300 may include a real time clock (RTC) unit 3226 and a timer 3227 that provide a real time clock. For example, a direct memory access controller (DMAC), which is the high-speed data transmission unit 226, may perform high-speed data communication with an external peripheral device along with a timer and high-speed pulse output.

The smart watt-hour meter 100 according to this embodiment includes a latch relay. A conventional circuit breaker is essentially used in a power distribution network for safe power use, and is always used in conjunction with a relay or operated artificially by a person. However, in the smart watt-hour meter 100 according to this embodiment, the processor 222 included in the processing unit 220 is configured to block the relay when the instant power consumption measured by the metering unit 210 rapidly increases. ) through which a blocking command is provided, and the peripheral device interface unit 300 receives the blocking command and controls the latch relay to be blocked.

A typical relay requires continuous power supply to maintain a cut-off state or a conduction state. However, since the latch relay included in the smart watt-hour meter 100 of the present embodiment maintains the state without separate power even when the conduction state and the cutoff state are maintained, the load can be controlled remotely without separate power supply through wired and wireless communication. control is possible Furthermore, according to the present embodiment, load shedding may be performed by wire or wirelessly through the communication unit (Comm.) on its own according to the type of power use.

The operation of the smart watt-hour meter 100 having the above configuration will be described. 4(a) to 4(c) are schematic diagrams for briefly describing the operation of the smart watt-hour meter 100 according to the present embodiment.

FIG. 4(a) is a diagram illustrating a process of transmitting the measured amount of power to a supplier through a wired and wireless communication peripheral device (Comm) included in the smart watt-hour meter 100 and a network. Referring to FIG. 4 (a), the smart watt-hour meter 100 according to the present embodiment can transmit necessary data through wired and wireless communication peripheral devices (Comm). In one embodiment, the wired and wireless communication peripheral devices (comm.) may transmit the monthly amount of power used measured by the metering unit 210 to the power supplier on a fixed date every month. For example, the wired and wireless communication peripherals (comm.) provide necessary information according to wireless communication protocols such as LTE, Wi-Fi, Zigbee, and Bluetooth or wired communication protocols such as Ethernet and serial. can send Therefore, there is no need for a meter reader to visit and read the user one by one.

4(b) is a diagram schematically illustrating a process of receiving firmware necessary for driving the smart watt-hour meter 100 through a network from a supplier. The wired and wireless communication peripheral devices (comm.) can receive firmware necessary for driving the smart watt-hour meter 100 and update it automatically and remotely. From this, it is possible to easily perform a firmware update when a rate policy is changed or maintenance of the smart watt-hour meter 100 is performed. Therefore, an advantage is provided that it can be continuously used without unnecessary machine replacement. The processing unit 220 may receive a firmware update file from the communication unit (comm.), and perform an update from a bootloader formed in the processing unit 220.

Wired and wireless communication peripherals (comm.) are formed to correspond to wireless communication and wired communication protocols, for example, wireless communication protocols such as LTE, Wi-Fi, Zigbee, Bluetooth, or the like It conforms to wired communication protocols such as Ethernet and serial. Furthermore, the smart watt-hour meter 100 according to this embodiment can be connected to an external modem (ext. modem) through serial communication such as RS485, so that data can be transmitted and received using various modems.

As an embodiment, a wired and wireless communication peripheral device (comm.) may be connected to a data collection device (not shown) for integrated meter reading through wired or wireless communication. A wired and wireless communication peripheral device (comm.) may acquire metering values such as gas and water from an integrated meter reading data collection device and display them on the display unit 130 .

4(c) is a diagram schematically illustrating a process in which a user remotely controls the smart watt-hour meter 100 through a network. A user can receive a power supply status for a specific device in the home to a portable terminal through a network, and can cut off power to the corresponding device by controlling a latch relay to which the corresponding device is connected. Referring to FIG. 4(c), the smart watt-hour meter 100 may transmit the amount of power consumed in the home to the user through wired and wireless communication peripheral devices (Comm.). When a user recognizes that a large amount of power is consumed by a specific device (eg, a lighting fixture), a control command to cut off power supplied to the corresponding device may be transmitted to a portable terminal such as a mobile phone or tablet through a network. The wired and wireless communication peripheral devices (Comm.) receive a control command through the network and provide the control command to the processing unit 220 through the peripheral device interface unit 300 . The processing unit 220 may provide a latch relay control signal according to a control command to control a latch relay to cut off power to a target device.

As described above, the smart watt-hour meter 100 according to the present embodiment includes a latch relay, and since the latch relay maintains a state without a separate power even when maintaining a conduction state and a cutoff state, separate The advantage of being able to remotely control the load without supplying power is provided.

As described above, the smart watt-hour meter 100 according to the present embodiment measures voltage and current by performing 3-fold oversampling. From this, the error rate of the existing active power measurement can be reduced from 1% to 0.5%, and the error rate of the existing reactive power measurement can be reduced from 2% to 1%.

Furthermore, while conventional watt-hour meters could measure only active power, the smart watt-hour meter 100 according to this embodiment is connected to a plurality of current sensors and a plurality of voltage sensors to measure reactive power, apparent power, voltage, frequency, and power factor. measurement is possible

If the power supplied to the house contains a lot of distortion, high-frequency noise is generated in images and sounds output to a display device such as a TV and an audio device such as an audio device. As described above, the conventional watt-hour meter merely has a function of accumulating the amount of power consumed in the house. You can find out if it is included.

The price of electricity consumed in a time zone when the amount of generated power is abundant is lower than the price of electricity when the amount of generated power is not abundant. That is, the value of power varies according to time zone. However, conventional watt-hour meters only perform a function of accumulating the amount of power consumed by a user, and cannot discriminate the price for the amount of power used by using how much power at a certain time.

However, the smart watt-hour meter 100 according to this embodiment provides a Time of Use (TOU) function. This provides a function of classifying and metering for each case when each rate is different according to usage time and season, so that the user can consume power economically.

The smart watt-hour meter 100 according to the present embodiment may connect a real-time clock device as a peripheral device to measure the amount of power consumed by the user and the power use time together. From this, not only the advantage of being able to charge real time pricing (RTP), but also the burden of the entire power grid can be reduced by utilizing real time pricing (RTP) under the smart grid environment.

In addition, the smart watt-hour meter 100 according to this embodiment inserts a single-phase two-wire or three-phase four-wire cable into the cable insertion part 130 and manipulates the button part 120 to supply power in various power supply methods. The amount of power consumed can be easily measured.

Although the present invention has been described in relation to specific embodiments of the present invention, this is only an example and the present invention is not limited thereto. Those skilled in the art to which the present invention belongs may change or modify the described embodiments without departing from the scope of the present invention, and within the scope of equivalents of the technical spirit of the present invention and the claims to be described below Many modifications and variations are possible.

100: smart power meter 110: display
112: alarm unit 120: button unit
H: housing 130: cable insertion
210: metering unit 212: analog-to-digital converter
214: digital signal processor 220: processing unit
222: processor 224: RAM
226: high-speed signal data transmission unit 228: interface controller
230: security unit 232: encryption engine
300: peripheral device interface unit 310: peripheral device interface
320: device control unit 3200: system control unit
3201: display control unit 321: communication control unit
3212: I2C communication controller 3214: SPI interface controller
3216: UART communication controller 3218: CAN communication controller
322: time controller 3226: RTC (326)
3227: Timer

Claims (10)

As a smart watt-hour meter, the smart watt-hour meter,
a metering unit that measures the amount of power consumed;
a processing unit controlling the smart watt-hour meter; and
Including; a peripheral device interface unit that interfaces the peripheral devices of the smart watt-hour meter;
The peripheral device interface unit includes a peripheral device interface that interfaces the processing unit and the peripheral device interface, a device controller that controls peripheral devices connected to the peripheral device interface, a communication controller, and a time controller;
The peripheral devices include wired and wireless communication peripheral devices,
The smart watt-hour meter is a smart watt-hour meter in which a user can control the smart watt-hour meter through a network.
According to claim 1,
The smart watt-hour meter is a smart watt-hour meter, characterized in that the amount of consumed power is measured for each usage time and usage date and separately measured for each rate.
According to claim 1,
The smart watt-hour meter further includes a plurality of current sensors and one or more voltage sensors,
The smart watt-hour meter, characterized in that the metering unit measures reactive power, apparent power, voltage, frequency, power factor and total harmonic distortion.
According to claim 1,
The smart watt-hour meter further includes a plurality of current sensors and one or more voltage sensors,
The smart watt-hour meter, characterized in that the metering unit measures reactive power, apparent power, voltage, frequency, power factor and total harmonic distortion.
According to claim 1,
The peripheral device further includes a latch relay connected to the device in the user's home,
The smart watt-hour meter, characterized in that the user remotely controls a latch relay included in the smart watt-hour meter to provide or cut off power to the in-house device.
According to claim 1,
The wired and wireless communication peripheral devices receive the firmware of the smart watt-hour meter from the network,
The smart watt-hour meter, characterized in that the processing unit updates the firmware of the smart watt-hour meter with the firmware received through a bootloader.
According to claim 1,
The smart watt-hour meter further includes a security unit,
The security unit includes an encryption engine that encrypts and decrypts transmitted and received data according to an AES-128 security algorithm.
According to claim 1,
The smart watt-hour meter is a smart watt-hour meter, characterized in that for transmitting the amount of power consumed on a predetermined date to a power supplier.
According to claim 1,
The metering unit includes an analog to digital converter (ADC) that converts a value measured using a current sensor and a voltage sensor into digital,
The analog-to-digital converter performs 3-fold oversampling.
According to claim 9,
The analog-to-digital converter is a smart watt-hour meter, characterized in that implemented as a programmable gate array (PGA).

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