Multi-channel intelligent three-phase electric meter and circuit

Abstract

The utility model discloses a kind of multi-channel intelligent three-phase electric meter and circuit, belong to three electric meter technical field, including electric meter shell, the top bolt of the electric meter shell is fixed with three-phase electric metering controller, the bottom bolt of the electric meter shell is fixed with three-phase electric current transformer, the three-phase electric current transformer is provided with several groups, the inner chamber of the electric meter shell is respectively provided with circuit board and energy storage device, the circuit board is connected with energy storage device electric wire, the surface of the circuit board is provided with bluetooth module, analog switch, remote wireless communication module and microcontroller, the demand of simultaneously monitoring of multiple lines, multiple areas under complex power consumption scene can be met by above-mentioned scheme, the adaptability of intelligent three electric meter is improved, can be flexibly adapted in wiring inconvenient, transmission distance far scene, improve the transmission efficiency and stability of data.

Description

Technical Field

[0001] This utility model relates to the field of three-phase electricity meter technology, specifically a multi-channel intelligent three-phase electricity meter and its circuit. Background Technology

[0002] Three-phase meters, a general term for electrical instruments, are meters used to measure electrical energy. They are also called electricity meters, watt-hour meters, or kilowatt-hour meters. Currently, smart meters are mainly used to measure the three-phase active power of low-voltage networks and to monitor various types of electricity consumption. They are widely used in industries such as smart transportation, charging piles, smart streetlights, energy consumption detection, smart factories, and remote power monitoring, providing functions such as electricity metering, remote telemetry, intelligent data statistics, and analysis.

[0003] However, existing smart meters have many technical limitations: First, they only support single-channel three-phase power monitoring, which makes it difficult to meet the needs of simultaneous monitoring of multiple lines and multiple areas in complex power consumption scenarios, greatly limiting their application in a wider range of scenarios; Second, they have a single communication method, supporting only wired communication or short-range wireless communication, which cannot be flexibly adapted to scenarios where wiring is inconvenient and transmission distances are long, seriously affecting data transmission efficiency and stability. Therefore, we need to propose a multi-channel smart three-phase meter and circuit. Utility Model Content

[0004] The purpose of this invention is to provide a multi-channel intelligent three-phase electricity meter and circuit. By setting up several sets of three-phase current transformers, multiple lines can be connected. Then, a hub is connected to an analog switch. By controlling the analog switch, the three-phase electricity metering controller can perform multi-line detection. With the cooperation of a remote wireless communication module and a Bluetooth module, data transmission can be carried out in long-distance scenarios. The above solution can meet the needs of simultaneous monitoring of multiple lines and multiple areas in complex power consumption scenarios, improve the adaptability of the intelligent three-phase electricity meter, and flexibly adapt to scenarios where wiring is inconvenient and transmission distances are long. It also improves the data transmission efficiency and stability, thereby solving the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a multi-channel intelligent three-phase electricity meter, comprising a meter housing, wherein a three-phase electricity metering controller is bolted to the top of the meter housing, and a three-phase current transformer is bolted to the bottom of the meter housing; several groups of the three-phase current transformers are provided, and the several groups of the three-phase current transformers are connected to an analog switch through a hub; a circuit board and an energy storage device are respectively provided in the inner cavity of the meter housing; the circuit board is wired to the energy storage device; a Bluetooth module, an analog switch, a remote wireless communication module, and a microcontroller are provided on the surface of the circuit board; the meter housing includes a front shell and a rear shell, and a connection mechanism for convenient connection is provided between the front shell and the rear shell.

[0006] Preferably, the connecting mechanism includes an elastic connecting plate, which is fixedly connected to the outer surface of the front shell. The surface of the elastic connecting plate is provided with a slot, and the inner cavity of the slot is provided with a locking block that matches the slot. The locking block is fixed to the outer surface of the rear shell.

[0007] Preferably, the end of the card block near the elastic connecting plate has a beveled surface, which is located on the outer side wall of the card block.

[0008] Preferably, a positioning block is fixedly connected to the surface of the front shell, and a positioning groove adapted to the positioning block is opened on the surface of the rear shell, and the surface of the positioning block is engaged with the inner cavity of the positioning groove.

[0009] Preferably, connecting plates are fixedly connected to both sides of the front shell, and a connecting groove adapted to the connecting plate is opened on the surface of the rear shell, and the surface of the connecting plate slides into the inner cavity of the connecting groove.

[0010] Preferably, threaded holes are provided on both sides of the rear shell, the inner cavity of the threaded hole is connected to the inner cavity of the connecting groove, a locking screw is threadedly connected to the inner cavity of the threaded hole, a fixing hole adapted to the locking screw is provided on the surface of the connecting plate, and the surface of the locking bolt is engaged with the inner cavity of the fixing hole.

[0011] This embodiment also provides a circuit for a three-phase electricity meter, including digital and analog input circuits, digital isolation and analog conditioning circuits, and power frequency filtering and protection circuits.

[0012] Compared with the prior art, the beneficial effects of this utility model are: This utility model provides a multi-channel intelligent three-phase electricity meter and circuit. By setting up several sets of three-phase current transformers, these transformers can be connected to different lines. After being connected to the lines, they are connected to an analog switch via a hub. The analog switch is then controlled to enable the three-phase electricity metering controller to perform multi-line detection. A remote wireless communication module allows for data transmission over long distances. A Bluetooth module, working in conjunction with the wireless communication module, improves data transmission stability. This solution meets the need for simultaneous monitoring of multiple lines and areas in complex electricity usage scenarios, enhancing the adaptability of the intelligent three-phase electricity meter. It can flexibly adapt to scenarios with inconvenient wiring and long transmission distances, improving data transmission efficiency and stability.

[0013] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objectives and other advantages of this invention can be realized and obtained through the structures pointed out in the description and the accompanying drawings. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the system frame of this utility model; Figure 2 This is a circuit diagram of the three-phase electricity metering controller and analog switch circuit of this utility model; Figure 3 This is a schematic diagram of the overall structure of this utility model; Figure 4 This is a side view of the structure of this utility model; Figure 5 This is a schematic diagram of the disassembled structure of the present invention; Figure 6 This is a rear view structural schematic diagram of the present invention.

[0015] In the diagram: 1. Digital and analog input circuits; 2. Digital isolation and analog conditioning circuits; 3. Memory; 4. Bluetooth module; 5. Remote wireless communication module; 6. Microcontroller; 7. Isolated RS485 driver; 8. Digital isolator; 9. Three-phase electricity metering controller; 10. Analog switch; 11. Hub; 12. Three-phase current transformer; 13. Energy storage device; 14. Linear regulator A; 15. Linear regulator B; 16. Isolated AC-DC converter; 17. Power frequency filter protection circuit; 18. Front shell; 19. Rear shell; 20. Flexible connecting plate; 21. Slot; 22. Block; 23. Positioning block; 24. Positioning groove; 25. Connecting plate; 26. Connecting groove; 27. Threaded hole; 28. Self-locking screw; 29. ​​Fixing hole. Detailed Implementation

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0017] Example 1

[0018] Please see Figure 3-6This utility model provides a technical solution: a multi-channel intelligent three-phase electricity meter, including a meter housing, a three-phase electricity metering controller 9 is fixed to the top of the meter housing with bolts, a three-phase current transformer 12 is fixed to the bottom of the meter housing with bolts, a circuit board and an energy storage device 13 are respectively arranged in the inner cavity of the meter housing, the circuit board and the energy storage device 13 are connected by wires, a Bluetooth module 4, an analog switch 10, a remote wireless communication module 5 and a microcontroller 6 are arranged on the surface of the circuit board, several groups of three-phase current transformers 12 are arranged, and several groups of three-phase current transformers 12 are connected to the analog switch 10 through a hub 11, the meter housing includes a front shell 18 and a rear shell 19, and a connection mechanism for easy connection is provided between the front shell 18 and the rear shell 19; In use, several sets of three-phase current transformers can be connected to different lines. After being connected to the lines, they are connected to the analog switch 10 via the hub 11. Then, the analog switch 10 is controlled to enable the three-phase electricity metering controller 9 to perform multi-line detection. The detected data is transmitted remotely through the cooperation of the remote wireless communication module 5 and the Bluetooth module 4. The above solution can meet the needs of simultaneous monitoring of multiple lines and multiple areas in complex power consumption scenarios, improve the adaptability of smart three-phase electricity meters, and flexibly adapt to scenarios where wiring is inconvenient and transmission distance is long, thereby improving the data transmission efficiency and stability.

[0019] The connecting mechanism includes an elastic connecting plate 20, which is fixedly connected to the outer surface of the front housing 18. A slot 21 is provided on the surface of the elastic connecting plate 20, and a locking block adapted to the slot 21 is provided in the inner cavity of the slot 21. The locking block is fixed to the outer surface of the rear housing 19. By cooperating with the elastic connecting plate 20 and the locking block, the locking block is inserted into the inner cavity of the slot 21, which allows the front housing 18 and the rear housing 19 to be quickly combined. By pushing the elastic connecting plate 20 outward, the locking block is moved out of the inner cavity of the slot 21, which releases the connection between the front housing 18 and the rear housing 19, making it convenient to disassemble the meter.

[0020] The end of the card block near the elastic connecting plate 20 has a beveled surface. The beveled surface is located on the outer wall of the card block. With the beveled surface, when the front shell 18 is pressed against the rear shell 19, the elastic connecting plate 20 will first come into contact with the beveled surface of the card block. After contact, the elastic connecting plate 20 moves outward, allowing the card block to be inserted into the inner cavity of the card slot 21. After the card block is inserted into the inner cavity of the card slot 21, the elastic connecting plate 20 is reset, so that the front shell 18 and the rear shell 19 are assembled, which facilitates the disassembly of the meter.

[0021] A positioning block is fixedly connected to the surface of the front shell 18, and a positioning groove adapted to the positioning block is opened on the surface of the rear shell 19. The surface of the positioning block and the inner cavity of the positioning groove are engaged and locked. Through the engagement of the positioning block and the positioning groove, the connection between the front shell 18 and the rear shell 19 can be supported, thereby improving the stability of the connection between the front shell 18 and the rear shell 19.

[0022] Both sides of the front housing 18 are fixedly connected to connecting plates, and the surface of the rear housing 19 is provided with connecting grooves that are adapted to the connecting plates. The surface of the connecting plates slides into the inner cavity of the connecting grooves. Through the cooperation of the connecting plates and the connecting grooves, the upper and lower sides of the meter can be supported after connection, further improving the stability after connection.

[0023] Both sides of the rear shell 19 are provided with threaded holes. The inner cavity of the threaded hole is connected to the inner cavity of the connecting groove. A locking screw is threaded into the inner cavity of the threaded hole. The surface of the connecting plate is provided with a fixing hole that matches the locking screw. The surface of the locking screw is engaged with the inner cavity of the fixing hole. After the rear shell 19 and the front shell 18 are combined, the locking screw is inserted into the threaded hole and rotated clockwise to move the locking screw inward through the threaded hole. When the locking screw moves to the inner cavity of the fixing hole, the position of the connecting plate in the connecting groove can be positioned.

[0024] This embodiment also provides a circuit for a three-phase electricity meter, including a digital and analog input circuit 1, a digital isolation and analog conditioning circuit 2, and a power frequency filter protection circuit 17. When in use, the microcontroller 6 collects external sensor data through the digital and analog input circuit 1 and the digital isolation and analog conditioning circuit 2 according to the configuration information, determines whether the trigger threshold is reached, links the corresponding three-phase electricity measurement channel, and opens the corresponding three-phase current loop through the analog switch 10. The cloud platform establishes communication with the microcontroller 6 through the remote wireless communication module 5 to realize real-time data reporting; when the external three-wire power supply is interrupted, the smart three-phase meter provides temporary power through the internal energy storage device 13 to ensure that the power outage status of the equipment and related data are saved and uploaded in a timely manner. Power frequency filter protection circuit 17: This circuit consists of an EMS protection circuit and an EMI filter circuit. The EMS protection is mainly composed of a varistor and a power winding resistor, and the EMI is mainly composed of a common mode inductor and a safety capacitor.

[0025] Example 2

[0026] Please see Figure 1-2A multi-channel intelligent three-phase electricity meter and circuit, comprising: 1. Digital and analog input circuits; 2. Digital isolation and analog conditioning circuits; 3. Memory; 4. Bluetooth module; 5. Remote wireless communication module; 6. Microcontroller; 7. Isolated RS485 driver; 8. Digital isolator; 9. Three-phase electricity metering controller; 10. Analog switch; 11. Hub; 12. Three-phase current transformer; 13. Energy storage device; 14. Linear regulator A; 15. Linear regulator B; 16. Isolated AC-DC converter; 17. Power frequency filtering and protection circuit; and multiple sets (each set monitors one three-phase circuit current) of three-phase current transformers 12. Hub 11 is connected to analog switch 10; microcontroller 6 collects external sensor data through digital isolation and analog conditioning circuit 2 based on configuration information and through digital and analog input circuit 1, determines whether the trigger threshold has been reached, links the corresponding three-phase power measurement channel, and opens the corresponding three-phase current loop through analog switch 10; cloud platform establishes communication with microcontroller 6 through remote wireless communication module 5 to realize real-time data reporting; when the external three-wire power supply is interrupted, the smart three-phase meter provides temporary power through internal energy storage device 13 to ensure that the power outage status of the equipment and related data are saved and uploaded in a timely manner.

[0027] The three-phase current transformer 12 draws power from the A-phase power supply and provides DC power to the smart three-phase meter through the power frequency filter protection circuit 17 and the isolation AC-DC converter 16. At the same time, the linear regulator B15 charges the energy storage device 13. When the external three-phase power is interrupted, the energy storage device 13 temporarily supplies power to the linear regulator A14, ensuring that the digital circuit of the smart three-phase meter can work for a certain period of time. The Bluetooth module 4 of the smart three-phase meter can be connected to the microcontroller 6 and the memory 3 via a mobile APP to enable near-end parameter configuration and data reading of the device.

[0028] Digital and analog input circuit 1: The input circuit mainly includes surge protection circuits, such as TVS diodes and PTC thermistors, to prevent damage to the smart three-phase meter when the external sensor input signal is over-voltage or over-current.

[0029] Digital isolation and analog conditioning circuit 2: The conditioning circuit mainly consists of two parts. The digital part uses optocoupler isolation and converts the voltage range of external digital signals into the range that the microcontroller 6 IO port can accept. The analog conditioning circuit mainly conditions the external voltage and current signals into the voltage measurement range of the built-in analog-to-digital converter of the microcontroller 6.

[0030] Memory 3: Large-capacity data storage uses solid-state SD cards. Compared with mechanical SD cards, solid-state SD cards are more reliable and will not be loosened by vibration, making them suitable for industrial applications.

[0031] Bluetooth module 4: Select a wireless communication module with a built-in protocol stack. Its internal data interface uses UART to communicate with microcontroller 6.

[0032] Remote wireless communication module 5: It can use cellular mobile communication networks such as 4G / NB-IoT, or it can be a remote wireless communication module 5 based on LoRaWAN. However, it works with a gateway to aggregate the data and send it to the cloud management platform.

[0033] Microcontroller 6: Since the smart three-phase electricity meter is a low-speed data processing device, the requirements for the microcontroller 6 are not high. A microcontroller 6 based on the Cortex-M3 core can be used to realize functions such as storage, communication, peripheral control, and reading of the three-phase electricity metering controller 9. At the same time, the built-in analog-to-digital converter can meet the measurement requirements of external analog signals.

[0034] Isolated RS485 Driver 7: The isolated RS485 driver 7 can employ an isolation chip solution that integrates communication and power supply. The external common-mode filter is primarily responsible for filtering out common-mode interference signals on the RS485 bus, preventing communication failure due to the RS485 common-mode voltage exceeding the chip's requirements. The surge protection circuit employs a two-stage surge protection system. The first stage typically uses a GDT to absorb large surges, while the second stage uses a TVS diode for precise clamping.

[0035] Digital Isolator 8: Since each data line of the SPI bus is a unidirectional communication, a four-channel unidirectional magnetic isolation, capacitive isolation, and optocoupler isolation type digital isolator 8 is sufficient.

[0036] Three-phase electricity metering controller 9: It adopts a three-phase electricity dedicated metering chip that can measure basic electrical quantities and electrical energy parameters, and realizes the measurement of parameters such as electrical energy, power, voltage, current and frequency.

[0037] Analog switch 10: See Figure 2 Solutions such as signal relays, analog switches, and multiplexers can be used. Figure 2 In this circuit, U2 is a 4:1 dual-channel multiplexer. Using four U2 chips can expand the three-phase current monitoring channels to four circuits. Similarly, using four 8:1 dual-channel multiplexers can achieve three-phase current monitoring of eight circuits. In practical use, to ensure measurement accuracy, the microcontroller 6 needs to control the switching speed of the analog switch 10 to meet the measurement requirements.

[0038] Hub 11: Its function is to gather the three pairs of wires (three pairs of differential wires, 6 wires) of the three-phase power of each circuit, so as to facilitate the connection to the smart three-phase power meter. It can be connected by junction box to RJ45 or plug-in connector.

[0039] Three-phase current transformer 12: A piercing-type switching current transformer can be used, which is convenient for installation and current measurement, and can simultaneously measure and extract three-phase voltage signals through the piercing lead. The specifications of the current transformer are selected according to the size of the three-phase load current being measured, such as a current transformer with a specification of 3*20 (100)A.

[0040] Energy storage device 13: Energy storage device 13 can use supercapacitors or lithium batteries, etc. Through a dedicated charging management chip, it can maintain a fully charged state when the monitored three-phase power supply is powered. When the monitored three-phase power supply is de-energized, the supercapacitor or lithium battery power supply is connected to the linear regulator A14 through an automatic switching circuit.

[0041] Linear regulator A14: It is mainly responsible for providing power to the microcontroller 6 and peripherals such as communication and memory 3. It is implemented using a low-power, low-dropout linear regulator.

[0042] Linear regulator B15: It is mainly responsible for powering the loads such as the three-phase electricity metering controller 9, analog circuit, isolation circuit, and conditioning circuit. It also adopts a low-power, low-dropout linear regulator.

[0043] Isolated AC-DC converter 16: Its function is to convert the AC power between phase A and neutral line N in a three-phase power supply into a low-voltage DC power supply. A dedicated isolated or non-isolated AC-DC converter 16 can be used.

[0044] Power frequency filter protection circuit 17: This circuit consists of an EMS protection circuit and an EMI filter circuit. The EMS protection circuit is mainly composed of a varistor and a power wire-wound resistor, while the EMI protection circuit is mainly composed of a common-mode inductor and a safety capacitor.

[0045] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A multi-channel smart three-phase electricity meter, characterized in that, include: The meter housing has a three-phase electricity metering controller (9) connected to the top of the meter housing and a three-phase current transformer (12) fixed to the bottom of the meter housing with bolts. The inner cavity of the meter housing is equipped with a circuit board and an energy storage device (13). The circuit board and the energy storage device (13) are connected by wires. The surface of the circuit board is equipped with a Bluetooth module (4), an analog switch (10), a remote wireless communication module (5), and a microcontroller (6). The three-phase current transformer (12) is provided in several groups, and the several groups of three-phase current transformers (12) are connected to the analog switch (10) through the hub (11); The meter housing includes a front housing (18) and a rear housing (19), and a connecting mechanism is provided between the front housing (18) and the rear housing (19) for easy connection.

2. The multi-channel intelligent three-phase meter according to claim 1, characterized in that: The connecting mechanism includes an elastic connecting plate (20) attached to the outer surface of the front shell (18). The surface of the elastic connecting plate (20) is provided with a slot (21), and the inner cavity of the slot (21) is provided with a locking block that is compatible with the slot (21).

3. A multi-channel intelligent three-phase meter according to claim 2, characterized in that: The end of the card block near the elastic connecting plate (20) has a beveled surface, and the beveled surface is located on the outer wall of the card block.

4. A multi-channel intelligent three-phase meter according to claim 1, characterized in that: The front shell (18) is fixedly connected to a positioning block, and the rear shell (19) is provided with a positioning groove that matches the positioning block.

5. A multi-channel intelligent three-phase meter according to claim 1, characterized in that: Both sides of the front shell (18) are fixedly connected to connecting plates, and the surface of the rear shell (19) is provided with connecting grooves that are adapted to the connecting plates.

6. A multi-channel intelligent three-phase meter according to claim 5, characterized in that: The rear shell (19) has threaded holes on both sides, the inner cavity of the threaded hole is connected to the inner cavity of the connecting groove, and the inner cavity of the threaded hole is threaded with a locking screw. The surface of the connecting plate is provided with fixing holes that are compatible with the locking screws.

7. A circuit for a multi-channel intelligent three-phase electricity meter, comprising the multi-channel intelligent three-phase electricity meter according to any one of claims 1-6, characterized in that, include: Digital and analog input circuits (1), digital isolation and analog conditioning circuits (2), and power frequency filtering and protection circuits (17).

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