Box-meter integrated metering device and signal processing method

Abstract

The embodiment of the invention discloses a box-meter integrated metering device and a signal processing method, and the device comprises an electric energy metering module which comprises a first signal collection circuit connected with a power line, and is configured to execute electric energy metering calculation based on the input of the first signal collection circuit and generate metering data; and the second signal acquisition circuit and the first signal acquisition circuit are connected in parallel to the power line, comprise voltage and current transformers connected in parallel and in series to the power line, and output original voltage and current signals. The original signal output module is directly connected with the secondary side of the mutual inductor, is provided with an analog signal channel, converts original signals into 0-5V or 4-20mA analog signals and outputs the analog signals; the analog-to-digital conversion unit is connected in parallel with the analog channel, converts an original signal into a digital signal, and outputs a data stream in an SP I / I 2C format through the digital signal channel. The device can output unprocessed original analog or digital signals, and the application scene of the metering device is expanded.

Description

Technical Field

[0001] This application relates to the technical field of power metering equipment, and specifically to an integrated box and meter metering device and a signal processing method. Background Art

[0002] In the current field of power metering equipment, traditional metering devices mostly adopt a decentralized structure. Their function interfaces are limited and can only output digital quantity data processed by a metering chip, unable to provide original signals or unprocessed digital signals, which restricts advanced applications such as fault diagnosis and energy efficiency analysis, and limits the expansion of application scenarios for metering devices. Summary of the Invention

[0003] This application aims to solve at least one technical problem existing in the prior art. To this end, embodiments of this application provide an integrated box and meter metering device and a signal processing method, which solve the problem of being unable to provide original signals or unprocessed digital signals in the prior art.

[0004] The object of this application can be achieved through the following technical solutions:

[0005] In a first aspect, this application provides an integrated box and meter metering device, and the metering device includes:

[0006] An electric energy metering module, including a first signal acquisition circuit connected to a power line, and the electric energy metering module is configured to perform electric energy metering calculation based on the input of the first signal acquisition circuit and generate metering data;

[0007] A second signal acquisition circuit, connected in parallel with the first signal acquisition circuit to the power line, including a voltage transformer and a current transformer. The primary side of the voltage transformer is connected in parallel to the power line, and the secondary side outputs an original voltage signal; the primary side of the current transformer is connected in series to the power line, and the secondary side outputs an original current signal;

[0008] An original signal output module, directly electrically connected to the secondary sides of the voltage transformer and the current transformer, including:

[0009] An analog signal channel, configured to convert the original voltage signal into a 0 - 5V original analog signal for output or convert the original current signal into a 4 - 20mA original analog signal;

[0010] An analog-to-digital conversion unit, arranged in parallel with the analog signal channel, and converts the original voltage signal and the original current signal into digital signals;

[0011] A digital signal channel, configured to output an SPI / I²C format data stream containing digital signals.

[0012] Optionally, the original signal output module includes:

[0013] The signal acquisition unit is directly connected to the secondary sides of the voltage transformer and the current transformer through a shielded cable;

[0014] The signal isolation and filtering circuit eliminates electromagnetic interference from the acquired original signals.

[0015] Optionally, the original signal output module further includes a protocol conversion unit that supports the conversion of Modbus, DL / T645, and MQTT communication protocols.

[0016] Optionally, the original signal output module further includes:

[0017] The software-defined interface unit is used to receive remote instructions and configure the signal output type and dynamically adjust the sampling frequency of the analog-to-digital conversion unit. The types include original analog signals, digital signals, or metering data;

[0018] Among them, the original signal output module can request and obtain metering data from the electric energy metering module through an internal bus or a communication interface.

[0019] Optionally, the original signal output module further includes:

[0020] The signal quality monitoring unit monitors the waveform distortion of the real-time original signal;

[0021] The channel switching unit automatically switches the output to the backup digital channel when it detects that the signal distortion exceeds the threshold. The backup digital channel is used to output the digital signal processed by the electric energy metering module.

[0022] Optionally, the original signal output module further includes:

[0023] The hardware encryption unit encrypts the output signal;

[0024] The device authentication unit verifies the legality of the access device through a digital certificate.

[0025] Optionally, it further includes an extended processor module. The extended processor module is integrated with the circuit of the original signal output module through a PCB board. The extended processor module is connected to the analog-to-digital conversion unit of the original signal output module through a parallel data bus to directly obtain digital signals. The control instruction output end of the extended processor module is connected to the software-defined interface unit of the original signal output module to dynamically adjust the sampling frequency of the analog-to-digital conversion unit or the signal channel enabling state.

[0026] Optionally, the first signal acquisition circuit includes:

[0027] The manganese copper shunt is connected in series to the primary side of the power line, and the secondary side outputs a power frequency current signal;

[0028] The residual current transformer has its primary side configured to simultaneously detect the phase current and neutral current of the power line, and its secondary side outputs a leakage current signal;

[0029] The voltage sampling circuit is connected in parallel to the power line and outputs a power frequency voltage signal;

[0030] The electric energy metering module further includes:

[0031] The metering core is connected to the manganese copper shunt, the residual current transformer and the voltage sampling circuit, and is configured to perform electric energy metering calculations on the power frequency current signal, the leakage current signal and the power frequency voltage signal;

[0032] The metering management core is communicatively connected to the metering core to obtain the electric energy calculation result and perform corresponding control.

[0033] Optionally, the metering device further includes:

[0034] The switch module is connected in series to the power line, and the control end of the switch module is connected to the electric energy metering module. When the detected leakage current exceeds the safety threshold, the switch module is triggered to cut off the power line;

[0035] The electric energy metering module, the original signal output module and the switch module are integrated in the box through a multi-layer PCB board.

[0036] In a second aspect, the present application provides a signal processing method for a metering device, including the following steps:

[0037] Collect the original signals of the power line through a voltage transformer and a current transformer;

[0038] Perform electromagnetic interference elimination processing on the original signals to generate preprocessed signals;

[0039] According to the preset output mode configuration, convert the preprocessed signals into the target signal type. When the analog signal mode is selected, output the original analog signals of 0-5V or 4-20mA; when the digital signal mode is selected, output the digital signals in SPI / I2C format;

[0040] Perform protocol encapsulation on the digital signal stream, and generate communication data packets compatible with the Modbus, DL / T645 or MQTT protocol through a protocol conversion unit;

[0041] Transmit the communication data packets to external Internet of Things devices.

[0042] One or more of the above embodiments of the present application have at least one or more of the following beneficial effects:

[0043] 1. By setting up the original signal output module, it can be directly connected to the secondary side of the voltage / current transformer to output the unprocessed original analog or digital signal. Different from the traditional device that can only output the processed digital signal, it can provide support for advanced data analysis such as fault diagnosis and energy efficiency analysis, expand the application scenarios of the metering device, and meet the intelligent needs of the power system.

[0044] 2. By setting up the software-defined interface unit, the signal output type and sampling frequency can be remotely configured, and users can flexibly select according to the scenario requirements, improving the adaptability of the device and meeting the diverse business needs.

[0045] 3. By integrating the electric energy metering module, the original signal output module and the switch module in the box through a multi-layer PCB board, it changes the problem of equipment redundancy caused by the separation of the meter box, the electric meter and the switch in the traditional metering device, reduces the cost, decreases the volume, saves the installation space, is convenient for transportation and installation, and improves the space utilization rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The following further describes the present application with reference to the drawings.

[0047] Figure 1 It is the principle block diagram of the metering device in one embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0048] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present application.

[0049] Please refer to Figure 1 As shown, in some embodiments, the present application provides an integrated meter-in-box metering device, and the metering device includes an electric energy metering module, a second signal acquisition circuit and an original signal output module.

[0050] Among them, the electric energy metering module includes a first signal acquisition circuit connected to the power line, and the electric energy metering module performs electric energy metering calculation based on the input of the first signal acquisition circuit and generates metering data.

[0051] The second signal acquisition circuit is connected in parallel with the first signal acquisition circuit to access the power line. The primary side of the voltage transformer is connected in parallel to the power line. In a high-voltage environment, using the principle of electromagnetic induction, the high voltage on the primary side is converted into a low voltage on the secondary side at a specific ratio, thereby outputting the original voltage signal; the primary side of the current transformer is connected in series to the power line, converting the large current on the primary side into a small current on the secondary side and outputting the original current signal.

[0052] The original signal output module is directly electrically connected to the secondary sides of the voltage transformer and the current transformer. A dedicated signal conversion circuit is provided in the analog signal channel, which can convert the original voltage signal into an original analog signal output of 0 - 5V or convert the original current signal into an original analog signal of 4 - 20mA. This conversion facilitates the subsequent unified processing and transmission of signals because the original analog signals have better compatibility and stability during transmission and processing.

[0053] The analog - to - digital conversion unit is arranged in parallel with the analog signal channel and uses a high - precision analog - to - digital conversion chip. This unit can convert the original voltage signal and the original current signal into digital signals to meet the signal - processing requirements of digital devices. The digital signal channel is configured to output an SPI (Serial Peripheral Interface) / I²C (Inter - Integrated Circuit) format data stream containing these digital signals. SPI / I²C is a common high - speed and stable digital communication protocol. Outputting in this format facilitates efficient data communication with other digital devices.

[0054] In this application, the second signal acquisition circuit is connected in parallel with the first signal acquisition circuit to access the power line. On the one hand, it can meet basic requirements such as electricity billing; on the other hand, by setting up the original signal output module, it can be directly connected to the secondary sides of the voltage / current transformers to output unprocessed original analog or digital signals. Different from traditional devices that can only output processed digital signals, this original signal output function provides strong support for advanced data analysis. In the fault diagnosis scenario, the waveform, phase and other information of the original signal can be used to more accurately judge power system faults; in terms of energy efficiency analysis, the energy utilization efficiency of the power system can be evaluated by deeply analyzing the original voltage and current signals, tapping the energy - saving potential, expanding the application scenarios of the metering device, and meeting the needs of the intelligent development of the power system.

[0055] In some embodiments, the raw signal output module includes a signal acquisition unit and a signal isolation and filtering circuit. The signal acquisition unit is directly connected to the secondary sides of the voltage transformer and the current transformer through a shielded cable. The shielded cable has good shielding performance, which can effectively reduce the influence of external electromagnetic interference on the acquired raw signals, ensuring the accuracy and stability of the acquired signals. The signal isolation and filtering circuit is connected after the signal acquisition unit to perform electromagnetic interference elimination processing on the acquired raw signals. This circuit adopts various filtering techniques, such as capacitor filtering, inductor filtering, etc., to remove the clutter and interference signals in the signals, guarantee the signal quality, make the signals for subsequent processing and transmission more reliable, enable the acquired raw signals to more truly reflect the actual situation of the power line, and provide a reliable data basis for subsequent analysis and applications based on the raw signals.

[0056] In some embodiments, the raw signal output module further includes a protocol conversion unit, which supports the conversion of communication protocols such as Modbus (a serial communication protocol in the field of industrial automation), DL / T645 (a Chinese power industry standard (standard number DL / T645 - 2007)), and MQTT (Message Queuing Telemetry Transport, a lightweight message transmission protocol for the Internet of Things). When the digital signal channel outputs a digital signal stream in SPI / I2C format, the protocol conversion unit receives this signal stream. For different external Internet of Things devices or systems, the protocol conversion unit converts the SPI / I2C format signal into the corresponding Modbus, DL / T645, or MQTT protocol format according to the required communication protocol. For example, if the external device communicates using the Modbus protocol, the protocol conversion unit will re - package and encode the digital signal according to the provisions of the Modbus protocol, add the corresponding protocol header, address information, check code, etc., to make it meet the requirements of the Modbus protocol, realize communication with the external device, and thus achieve cross - platform interoperability. Supporting the conversion of multiple communication protocols enables the metering device to perform data interaction with Internet of Things devices with different communication protocols, improves the compatibility and versatility of the device, breaks the communication barriers between different systems and devices, and facilitates integration and use in various Internet of Things application scenarios.

[0057] In some embodiments, the original signal output module further includes a software-defined interface unit, which is used to receive remote instructions. This unit receives instructions from the remote control end through a network connection (such as Ethernet, wireless communication network, etc.). When an instruction is received, the software-defined interface unit configures the signal output type and dynamically adjusts the sampling frequency of the analog-to-digital conversion unit according to the instruction content. If the instruction requires the output of an original analog signal, the software-defined interface unit will control the analog signal channel to perform corresponding signal conversion and output; if the output of a digital signal is required, it will control the digital signal channel to output; if the output of measurement data is needed, the software-defined interface unit will obtain relevant data from the power measurement module and output it. Among them, data interaction between the software-defined interface unit and the power measurement module is carried out through an internal bus (such as SPI bus or I2 bus) or a communication interface (such as UART interface).

[0058] Meanwhile, according to the sampling frequency setting in the instruction, the software-defined interface unit sends a control signal to the analog-to-digital conversion unit to dynamically adjust its sampling frequency to meet the requirements of signal acquisition frequency in different application scenarios. Users can remotely and flexibly configure the signal output type and sampling frequency according to the different requirements of the actual application scenario. For example, in a fault diagnosis scenario, it may be necessary to obtain original digital signals with a high sampling frequency to analyze signal details; in a regular monitoring scenario, original analog signals with a lower sampling frequency can be selected to reduce data transmission volume and processing complexity, improving the adaptability and flexibility of the device.

[0059] In some embodiments, the signal quality monitoring unit of the original signal output module monitors the waveform distortion degree of the original signal in real time. This unit calculates the waveform distortion degree of the signal by performing real-time analysis on the collected original voltage and current signals. When it detects that the signal distortion degree exceeds the preset threshold, the signal quality monitoring unit sends a switching signal to the channel switching unit. After receiving the switching signal, the channel switching unit automatically switches the output to the backup digital channel. The backup digital channel is connected to the power measurement module and is used to output the digital signals processed by the power measurement module. Since the power measurement module has processed the signals, these digital signals have high stability and accuracy. After switching, it can ensure the continuous and stable output of data, avoid data errors or losses caused by the distortion of the original signal, and ensure the reliability of signal output.

[0060] In some embodiments, the hardware encryption unit of the original signal output module encrypts the output signal. The hardware encryption unit adopts specific encryption algorithms (such as SM1 / SM4 / SM2 / SM3, etc.) to encrypt analog signals or digital signals before signal output. The original signal is transformed according to the rules of the encryption algorithm, and the ciphertext signal is generated before output. The device authentication unit verifies the legitimacy of the access device through digital certificates. When an external device attempts to access the metering device, the device authentication unit will obtain the digital certificate of the external device and verify the certificate. Information such as the issuing authority, validity period, and whether the certificate content is complete and legal is checked. Only the devices that pass the verification can perform data interaction with the metering device, preventing illegal devices from accessing and obtaining sensitive data, and enhancing data security.

[0061] In some embodiments, the metering device further includes an extended processor module, which is integrated with the circuit miniaturized PCB board of the original signal output module. The extended processor module is connected to the analog-to-digital conversion unit of the original signal output module through the circuit on the PCB board to directly obtain the digital signal; the control instruction output end of the extended processor module is connected to the software-defined interface unit of the original signal output module to dynamically adjust the sampling frequency or signal channel enabling state of the analog-to-digital conversion unit, improving the functional expandability of the device. The extended processor module dynamically adjusts the signal acquisition and output parameters by controlling the software-defined interface unit, enabling the device to better adapt to different application scenarios and functional requirements, and enhancing the intelligence and personalization capabilities of the device.

[0062] In addition, the function of the extended processor module is not limited to managing the original signal output module. It can also use the original digital signal for other extended applications. For example, it can perform power quality analysis using the original digital signal. The extended processor module can deeply analyze the original digital signal, and through complex algorithms and models, accurately calculate various quality indicators of electric energy, such as voltage fluctuation, harmonic content, power factor, etc., providing strong support for the stable operation and optimized management of the power system.

[0063] In some embodiments, the first signal acquisition circuit includes a manganese copper shunt, a residual current transformer, and a voltage sampling circuit. The primary side of the manganese copper shunt is connected in series to the power line to collect the power frequency current signal. The primary side of the residual current transformer is configured to detect the phase line and neutral line currents of the power line simultaneously. Under normal circumstances, the vector sum of the currents in the power line is zero, but when a leakage occurs, a residual current will be generated. The residual current transformer can sense this residual current and output a leakage current signal on the secondary side. The voltage sampling circuit is connected in parallel to the power line and collects the power frequency voltage signal in the power line through circuit means such as resistor voltage division and capacitor filtering.

[0064] The electric energy metering module further includes a metering core and a metering management core. The metering core is connected to a manganese copper shunt, a residual current transformer, and a voltage sampling circuit, and receives the signals collected by these components. A complex electric energy metering algorithm is integrated inside the metering core. According to the amplitude, phase, and other information of these signals, and in accordance with the principles and algorithms of electric energy metering, electric energy metering calculations are performed to generate metering data. The metering management core is communicatively connected to the metering core, obtains the electric energy calculation results of the metering core through a UART (Universal Asynchronous Receiver-Transmitter) interface, and then performs corresponding controls based on these results, such as controlling the on / off of the subsequent switch module, to achieve the protection and management of the power system.

[0065] The metering management core also works in cooperation with the extended processor module, and the two are connected through SPI or other communication methods. The extended processor module can use the electric energy data provided by the metering management core to establish a traceability system for charging data and legal metrology data, providing a solid data foundation for subsequent metering verification, cost settlement, etc.

[0066] In some embodiments, the electric energy metering module further includes a power supply unit, a security unit, a storage unit, a Bluetooth communication unit, a display unit, a power detection unit, and a carrier unit.

[0067] The power supply unit serves as the power supply hub of the entire metering device. It undertakes the task of converting the externally input electrical energy into an electrical energy form suitable for the use of various components inside the device, and can convert the unstable input power supply into a stable DC power output. By precisely adjusting the voltage and current, it provides stable and reliable power support for various chips, modules, and circuits in the device, ensuring the stable operation of the device under different working conditions. The power supply unit includes the first branch power supply and the second branch power supply. The first branch power supply mainly powers the metering management core. The metering management core is the core of the device operation control and data processing, responsible for obtaining, storing the electrical energy calculation results, and controlling and coordinating various parts of the device. The first branch power supply provides continuous and stable power for it, enabling the metering management core to execute instructions, process data, and control other components normally. When storing data, the first branch power supply ensures that the metering management core has enough power to accurately write the data into the storage unit; when communicating data, it ensures normal communication with other modules such as the carrier module and the Bluetooth communication module, realizing data transmission and interaction. The second branch power supply is dedicated to providing electrical energy for the metering core. The metering core is the key component for realizing electrical energy metering. It accurately calculates electrical energy by collecting and processing voltage / current signals. The second branch power supply provides stable power for it, ensuring that the metering core can accurately collect and process signals, thereby ensuring the accuracy of electrical energy metering. When the voltage transformer and current transformer collect signals, the second branch power supply ensures that the metering core can stably receive and process these signals without being interfered by power fluctuations, thus ensuring the reliability of the electrical energy metering result.

[0068] The security unit is connected to the metering management core through SPI or other communication methods. When the metering management core performs operations such as data storage and transmission, the security unit will encrypt the data and at the same time verify the legality of external devices or data access, ensuring the security of data during transmission and storage.

[0069] The storage unit is connected to the metering management core through interfaces such as SPI or I2C. The storage unit is used to store metering data, configuration information, and historical data during the operation of the device, etc. The metering management core stores data such as electrical energy calculation results, calibration parameters of the device, and user settings into the storage unit. When the device loses power or historical data needs to be queried, the metering management core can read the data from the storage unit to ensure the persistence and traceability of the data.

[0070] The Bluetooth communication unit is connected to the metering management core through communication interfaces such as UART. The Bluetooth communication module is mainly used to realize short-distance wireless communication. With the help of the Bluetooth communication module unit, the metering management core can perform data interaction with external devices with Bluetooth functions (such as mobile phones, handheld terminals, etc.). On-site maintenance personnel can use a mobile phone to connect to the device via Bluetooth, read metering data, view the device status, and can also perform operations such as parameter setting on the device, improving the convenience of on-site operations.

[0071] The display unit is connected to the metering management core through I2C or other control buses. The display unit is used to visually display the operating status and metering data of the device. The display unit includes indicator lights and buttons. The metering management core sends relevant information to the display unit. The indicator lights can display the working status of the device (such as power status, communication status, etc.), and the buttons allow users to interact with the device. Users can query metering data for different periods, switch display interfaces, etc. through the buttons, enhancing the human-computer interaction ability of the device.

[0072] The power detection unit is connected to the metering management core and monitors the power status in real time. The power detection unit is responsible for monitoring parameters such as voltage and current of the first power supply and the second power supply, and feeding this information back to the metering management core. The metering management core judges whether the power supply is working properly according to the data provided by the power detection unit. When abnormal power supply is detected (such as too low voltage, too high voltage or abnormal current), the metering management core can take corresponding measures, such as issuing an alarm, saving important data or controlling the device to enter the low-power mode, to ensure the stable operation of the device under different power conditions.

[0073] The carrier unit is connected to the metering management core through communication interfaces such as UART. The carrier unit uses the power line as the communication medium for data transmission. The metering management core sends the data to be transmitted to the carrier unit, and the carrier unit modulates the data onto the power line for transmission, realizing functions such as remote meter reading and remote control, and playing an important role in the centralized meter reading of the power system network.

[0074] In some embodiments, the metering device includes a switch module. The switch module is connected in series on the power line, and its control end is connected to the metering management core in the electric energy metering module. When the residual current transformer in the electric energy metering module monitors that the leakage current exceeds the safety threshold, after receiving this information, the metering management core sends a cut-off signal to the switch module through the control end. After receiving the signal, the switch module quickly cuts off the power line to prevent safety accidents caused by electric leakage. The electric energy metering module, the original signal output module and the switch module are integrated in the box through a multi-layer PCB board. The box has an IP68 rating and provides physical protection and installation support for each module inside the box.

[0075] This application also provides a signal processing method based on the above metering device, and the specific steps are as follows:

[0076] First, collect the original signals of the power line through a voltage transformer and a current transformer. The voltage transformer converts the high voltage in the power line into a low voltage, and the current transformer converts the large current into a small current, and outputs the original voltage signal and the original current signal respectively.

[0077] Then, perform electromagnetic interference elimination processing on the collected original signal. Through signal isolation and filtering circuits, such as using techniques like capacitive filtering, inductive filtering, and optoelectronic isolation, remove the electromagnetic interference in the signal to generate a preprocessed signal and improve the signal quality.

[0078] Next, according to the preset output mode configuration, convert the preprocessed signal into the target signal type. When the analog signal mode is selected, the signal conversion circuit in the analog signal channel converts the preprocessed signal into an original analog signal of 0 - 5V or 4 - 20mA for output; when the digital signal mode is selected, the analog - to - digital conversion unit converts the preprocessed signal into a digital signal, and then the digital signal channel outputs a digital signal in SPI / I²C format.

[0079] After that, perform protocol encapsulation on the digital signal stream. The protocol conversion unit re - encodes and encapsulates the digital signal according to the preset communication protocol (Modbus, DL / T645, or MQTT), adding a protocol header, address information, checksum, etc., to generate a communication data packet compatible with the corresponding protocol.

[0080] This signal processing method ensures signal quality through electromagnetic interference elimination processing. Multiple output modes and protocol conversions meet the access requirements of different devices, achieve seamless docking between the metering device and Internet of Things devices, and improve the accuracy and compatibility of data transmission.

[0081] The above has described a detailed embodiment of the present application, but the content described is only a preferred embodiment of the present application and cannot be considered as limiting the scope of implementation of the present application. All equivalent changes and improvements made within the scope of the present application should still fall within the patent coverage scope of the present application.

[0082] It should be noted that the "first", "second", and similar terms used in the present application do not indicate any order, quantity, or importance, but are only used to distinguish different components. The descriptions of directions such as "left", "right", "left side", "right side", "upper part", "lower part", "top", "bottom", etc. in the present application are all defined based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the structure must be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation to the present application. In the description of the present application, "a plurality" means two or more, unless otherwise specifically defined.

[0083] In the description of the present application, unless otherwise clearly defined and limited, the terms "installed", "connected", and "coupled" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

Claims

1. A box-table integrated metering device, characterized in that, The metering device includes: An electric energy metering module, including a first signal acquisition circuit connected to a power line. The electric energy metering module is configured to perform electric energy metering calculations based on the input of the first signal acquisition circuit and generate metering data. A second signal acquisition circuit, connected in parallel with the first signal acquisition circuit to the power line, including a voltage transformer and a current transformer. The primary side of the voltage transformer is connected in parallel to the power line, and the secondary side outputs an original voltage signal. The primary side of the current transformer is connected in series to the power line, and the secondary side outputs an original current signal. An original signal output module, directly electrically connected to the secondary sides of the voltage transformer and the current transformer, including: An analog signal channel, configured to convert the original voltage signal into an original analog signal of 0 - 5V for output or convert the original current signal into an original analog signal of 4 - 20mA. An analog-to-digital conversion unit, arranged in parallel with the analog signal channel, converting the original voltage signal and the original current signal into digital signals. A digital signal channel, configured to output an SPI / I2C format data stream containing the digital signals.

2. The metering device according to claim 1, wherein, The original signal output module includes: A signal acquisition unit, directly connected to the secondary sides of the voltage transformer and the current transformer through a shielded cable. A signal isolation and filtering circuit, performing electromagnetic interference elimination processing on the acquired original signals.

3. The metering device according to claim 2, characterized in that, The original signal output module further includes a protocol conversion unit, supporting the conversion of Modbus, DL / T645, and MQTT communication protocols.

4. The metering device according to claim 1, characterized in that, The original signal output module further includes: A software-defined interface unit, used to receive remote instructions and configure the signal output type and dynamically adjust the sampling frequency of the analog-to-digital conversion unit. The types include original analog signals, digital signals, or metering data. Wherein, the original signal output module can request and obtain the metering data from the electric energy metering module through an internal bus or a communication interface.

5. The metering device according to claim 1, characterized in that, The original signal output module further includes: A signal quality monitoring unit, monitoring the waveform distortion degree of the real-time original signal. A channel switching unit, when detecting that the signal distortion degree exceeds a threshold, automatically switching the output to a backup digital channel, and the backup digital channel is used to output the digital signal processed by the electric energy metering module.

6. The metering device according to claim 1, characterized in that, The original signal output module further includes: A hardware encryption unit, encrypting the output signal. A device authentication unit, verifying the legality of the access device through a digital certificate.

7. The metering device according to claim 1, characterized in that, It further includes an extended processor module. The circuit of the extended processor module is integrated with the original signal output module through a PCB board. The extended processor module is connected to the analog-to-digital conversion unit of the original signal output module through a parallel data bus to directly obtain the digital signals. The control instruction output end of the extended processor module is connected to the software-defined interface unit of the original signal output module to dynamically adjust the sampling frequency of the analog-to-digital conversion unit or the signal channel enabling state.

8. The metering device according to claim 1, characterized in that The first signal acquisition circuit includes: A manganin shunt, with its primary side connected in series to the power line and its secondary side outputting a power frequency current signal. Residual current transformer, the primary side is configured to simultaneously detect the phase current and neutral current of the power line, and the secondary side outputs a leakage current signal; Voltage sampling circuit, connected in parallel to the power line, and outputs a power frequency voltage signal; The electric energy metering module further includes: Metering core, connected to the manganese copper shunt, residual current transformer and voltage sampling circuit, and configured to perform electric energy metering calculation on the power frequency current signal, leakage current signal and power frequency voltage signal; Metering management core, communicatively connected to the metering core, and obtains the electric energy calculation result for corresponding control.

9. The metering device according to claim 1, characterized in that, The metering device further includes: Switch module, connected in series on the power line, the control end of the switch module is connected to the electric energy metering module, and when the detected leakage current exceeds the safety threshold, the switch module is triggered to cut off the power line; The electric energy metering module, the original signal output module and the switch module are integrated in the box through a multi-layer PCB board.

10. A signal processing method for a metering device according to any one of claims 1-9, characterized in that, Including the following steps: Collect the original signal of the power line through a voltage transformer and a current transformer; Perform electromagnetic interference elimination processing on the original signal to generate a preprocessed signal; According to the preset output mode configuration, convert the preprocessed signal into the target signal type. When the analog signal mode is selected, output the 0-5V or 4-20mA original analog signal; when the digital signal mode is selected, output the SPI / I2C format digital signal; Perform protocol encapsulation on the digital signal stream, and generate a communication data packet compatible with the Modbus, DL / T645 or MQTT protocol through the protocol conversion unit; Transmit the communication data packet to an external Internet of Things device.

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