Intelligent electric energy meter circuit of M-BUS host communication interface

Abstract

The utility model relates to an intelligent electric energy meter circuit of an M-BUS host communication interface. The intelligent electric energy meter circuit comprises a host controller U4 and a physical layer interface connected with the host controller U4. The input end of the host controller MCU is electrically connected with a metering unit, a power management module and a key module; the output end of the host controller U4 is electrically connected with an LCD display module, an indicating lamp and a load switch. The host controller U4 is electrically connected with a host communication interface, an M-bus host communication interface unit and an uplink module communication interface; the metering unit is electrically connected with a power module; the power module is electrically connected with the battery module; the power module and the battery module are electrically connected with the power management module; the device is reasonable in design, compact in structure and convenient to use.

Description

Technical Field

[0001] The utility model relates to an intelligent electric energy meter circuit of an M-BUS host communication interface. Background Art

[0002] In the process of the development of smart meters, especially smart water meters, smart gas meters and smart heat meters, there are two core problems: 1. The power supply problem of smart meters: At present, the commonly used method is to configure a power supply for each meter separately, or rely on energy storage devices such as batteries for power supply, but this increases the maintenance cost to a certain extent, and the battery life and replacement issues have become factors that restrict its long-term stable operation. 2. User data transmission problem: The data collected by each meter usually has an independent transmission link to upload to the main station, which increases the complexity of network construction and maintenance to a certain extent. At the same time, how to ensure the security, stability and efficiency of data transmission is also a technical challenge that needs to be optimized. To solve these problems, the industry is actively exploring new energy collection technologies, low-power wireless communication technologies and data encryption transmission technologies, striving to reduce operation and maintenance costs while ensuring the efficient operation of smart meters, improve user experience, and promote the construction of smart city infrastructure to a new level. Utility Model Content

[0003] The technical problem to be solved by the utility model is generally to provide a smart energy meter circuit with an M-BUS host communication interface. The energy meter can not only perform its own electric energy metering tasks, but also play multiple functions through the integrated M-Bus host communication interface. The smart energy meter of the utility model integrates an M-Bus host communication module and provides an M-Bus bus interface; the power supply function of the smart energy meter is integrated, and the smart energy meter can not only power itself, but also power other smart meters through the M-Bus bus interface; the smart energy meter enhances the data interaction capability between the smart energy meter and other smart meters through the M-Bus bus interface.

[0004] In order to solve the above problems, the technical solution adopted by the utility model is:

[0005] An intelligent electric energy meter circuit with an M-BUS host communication interface includes a host controller U4 and a physical layer interface connected to the host controller U4; a metering unit, a power management module and a key module are electrically connected to an input end of the host controller MCU;

[0006] The output end of the host controller U4 is electrically connected to an LCD display module, an indicator light and a load switch;

[0007] The host controller U4 is electrically connected to the host communication interface, the M-bus host communication interface unit and the uplink module communication interface;

[0008] The metering unit is electrically connected to a power module; the power module is electrically connected to a battery module; the power module and the battery module are electrically connected to a power management module.

[0009] Furthermore, the power management module includes a rectifier D1, a power chip U1, a transformer RN1, and an optocoupler UN1;

[0010] The power supply is divided into two paths through the rectifier D1;

[0011] The first path passes through the series resistors R3 and R15 and connects to the PRO channel through PRO; the second path is connected to the primary coil of the transformer RN1, and a diode is connected in series after the parallel capacitor C5 and resistor R4 between the primary coils of the transformer RN1;

[0012] One path of the output end of the primary coil of the transformer RN1 is connected to SOURCE through the capacitor C13, and the second path is connected to pin 14 of the power chip U1;

[0013] In the chip U1, pin 5 is connected to the PRO channel, pin 6 is connected to the optocoupler UN1, pin 9 is connected to SOURCE, and pin 3 is connected to the resistor R29;

[0014] One end of the first secondary coil of the transformer RN1 is grounded, and the other end is connected to the resistor R29 after passing through the unit of the series resistor R26 and capacitor C21 and the parallel diode D12;

[0015] The second secondary coil of the transformer RN1 is connected to SPN+, and the third secondary coil is connected to VCC for power supply;

[0016] The optocoupler UN1 is connected to SPM+ for triggering the power chip U1.

[0017] Furthermore, the power management module also includes an MCU system power supply, a clock power supply, and an interface power supply system;

[0018] The MCU system power supply includes a chip UQ1; in the chip UQ1, pin 1 is connected to the VCC power supply, pin 1 is connected to the resistor RQ1 and then to pin 6, pin 6 outputs 3V3 through the filter unit inductor LQ1 and capacitor C3; 3V3 is grounded through the zener diode EQ1; pin 3 is connected to 3V3 through the resistor RQ2;

[0019] The interface power supply system includes a chip UQ2, and the input voltage SPM+ outputs +5V through the chip UQ2;

[0020] The clock power supply includes a battery BAT1. One path of the battery BAT1 outputs 3V3 through the diode D11, and the other path outputs BAT ADC through the resistor R27.

[0021] Furthermore, the uplink module communication unit includes a chip U5 and a chip U6, and the host controller U4 is electrically connected to the interface RS1 through the series-connected chips U5 and U6;

[0022] The metering unit includes a metering pulse output unit, which includes metering unit chips UO1 and UO2; the metering unit chips UO1 and UO2 are respectively connected to channels PF and QF, and the output is connected to interface JO1;

[0023] The M-bus host communication interface unit includes optocouplers U9 and U10, and chip U7; the optocouplers U9 and U10 are connected to the corresponding channels of the host controller U4; the optocoupler U9 is connected to the chip U7, and the chip U7 is connected to interface J2;

[0024] The optocoupler U10 is connected to interface J2 after passing through the secondary control triode group Q11 and Q12.

[0025] Furthermore, the host controller U4 is connected to a magnetic field detection system, and the magnetic field detection system includes a chip U8 electrically connected to the host controller U4 to detect the influence of the magnetic field on the circuit;

[0026] The metering unit includes a chip U15; the chip U15 is connected to the 3V3 voltage, and the chip U15 is electrically connected to the host controller U4.

[0027] Furthermore, the metering unit is electrically connected to a current sampling circuit and a voltage sampling circuit;

[0028] In the current sampling circuit, there are I+ acquisition terminals and I- acquisition terminals. The I+ acquisition terminal is divided into two paths. One path is grounded through a resistor R85, and the other path is connected to a resistor R77. The output terminal of the resistor R44 is respectively connected to the chip U15 and grounded through a capacitor C55;

[0029] The I- acquisition terminal is divided into two paths. One path is grounded through a resistor R91, and the other path is connected to a resistor R93. The output terminal of the resistor R93 is respectively connected to the chip U15 and grounded through a capacitor C58;

[0030] In the voltage sampling circuit, the voltage terminal UN is divided into two paths through a resistor R74; one path is connected to the VLP of the chip U15, and the other path is grounded after being connected in parallel with a resistor R75 and a capacitor C51. The VLN of the chip U15 is grounded through a parallel combination of a resistor R86 and a capacitor C57.

[0031] Furthermore, the host controller U4 is electrically connected to a load switch control detection circuit;

[0032] The load switch control detection circuit includes a relay WJ and a coil control circuit electrically connected to the relay WJ;

[0033] The coil control circuit includes a chip U13 and an optocoupler U14 respectively electrically connected to the host controller U4;

[0034] The chip U13 and the optocoupler U14 are respectively electrically connected to the relay WJ;

[0035] The load switch control detection circuit is electrically connected to the metering unit; the metering unit is electrically connected to the relay WJ;

[0036] The host controller U4 is also electrically connected to the infrared communication interface and the radio frequency communication interface;

[0037] The button module includes a liquid crystal display screen and buttons.

[0038] The utility model meets the requirements of power supply and data transmission, realizes integrated power supply and meter user data transmission, can realize data transmission and power supply of multiple metering devices on a single twisted pair wire, and significantly reduces the wiring cost and complexity. It can not only provide stable power supply for itself, but also provide power for other intelligent meters through the same line, and synchronously collect and transmit the usage data of these meters. In this way, not only the installation process is simplified, the hardware investment is reduced, but also the efficiency of data collection and transmission is greatly improved, and it is also convenient for centralized management and maintenance. This integrated design scheme effectively solves the power supply problem and technical bottleneck in the practical application of intelligent meters, and strongly promotes the overall development of the intelligent meter industry and the pace of smart city construction. Brief Description of the Drawings

[0039] Figure 1 It is a schematic diagram of the host communication module of the utility model.

[0040] Figure 2 It is a schematic structural diagram of the host communication module of the utility model.

[0041] Figure 3 It is a schematic structural diagram of the communication interface of the utility model.

[0042] Figure 4 It is a schematic diagram of the MCU module of the utility model.

[0043] Figure 5 It is a schematic structural diagram of the power supply module of the utility model.

[0044] Figure 6 It is a schematic structural diagram of the power module of the utility model.

[0045] Figure 7 It is a schematic diagram of the communication module of the utility model.

[0046] Figure 8 It is a schematic structural diagram of the metering pulse module of the utility model.

[0047] Figure 9 It is a schematic structural diagram of the M-BUS host communication of the utility model.

[0048] Figure 10 It is a schematic diagram of the magnetic field detection module of the utility model.

[0049] Figure 11 It is a schematic diagram of the voltage and current measurement and sampling module structure of the present utility model.

[0050] Figure 12 It is a schematic diagram of the switch control structure of the present utility model. Detailed implementation manners

[0051] As Figures 1-12 , the present utility model belongs to the technical field of intelligent electric meters, and specifically relates to a circuit technology of an intelligent electric energy meter with an M-Bus host communication interface. The core of this technical solution lies in designing and implementing an intelligent electric energy meter, which can not only perform its own electric energy measurement task, but also play multiple functions through the integrated M-Bus host communication interface. The utility model of this circuit is applied to the field of intelligent electric meters.

[0052] As Figures 1-12 , the design and implementation of a circuit of an intelligent electric energy meter with an M-Bus host communication interface are shown in Figure 1 , which includes a host controller and a physical layer interface. As Figure 4 , the host controller is the MCU (microprocessor), which is responsible for tasks such as packet packing and unpacking, error detection and correction, and protocol conversion; the physical layer interface is responsible for sending and receiving signals through the M-Bus bus. The design and implementation of the M-Bus host communication module are shown in Figure 2 .

[0053] Among them, the host controller MCU module U4: The host controller is the core part responsible for managing and executing the M-Bus protocol; the physical layer interface is mainly responsible for signal conversion and transmission to ensure that the electrical signals meet the requirements of the M-Bus standard. As the isolation part for communication with the electric energy meter, an optocoupler is mainly used for electrical isolation, which not only has a high transmission rate but also can avoid personal injury caused by abnormal electric energy meter leakage. It also includes signal shaping, level conversion, anti-interference design, and decoupling and matching of signals.

[0054] As Figure 5 , 6 , Power management: The switching power supply module is a very crucial component, which needs to provide a stable DC power supply, providing +24VDC for the host controller and the physical layer interface respectively, and +12V DC for the MCU. The isolation power topology structure is adopted to enhance the safety of the system and prevent high voltage from being introduced into the low voltage part, causing equipment damage or personal electric shock risk. Therefore, the selected power module should have good electrical isolation performance, meeting at least 4KV of AC withstand voltage and 6KV of impulse voltage protection level.

[0055] In addition to electrical isolation, there are also measures such as overload protection, short-circuit protection, and lightning protection to improve the stability and reliability of the entire module when working in a harsh environment. When designing the M-Bus communication module, not only the communication protocol needs to be implemented, but also the design and safety characteristics of the power supply system need to be ensured to make the overall solution meet both communication requirements and industry safety standards.

[0056] Voltage and current metering and sampling module, design of the metering module: This part is responsible for the accurate metering of electrical energy, including voltage and current sampling, as well as an electrical energy metering chip for calculating and recording the electricity consumption of users; for voltage sampling, a voltage division design using 7 high-precision, low-temperature-drift surface-mount resistors in 1206 packages is adopted, and for current sampling, a high-precision manganin shunt and a current transformer with a small angular difference are used. The effective maximum input differential signal rms value of the ADC of the selected metering chip is 1000 mV, and the dynamic range is 8000:1. It can be known that the minimum differential signal for effective metering of the metering chip is 0.125 mV, that is, the input of each sampling circuit is between 0.125 mV and 1000 mV, and the metering error ensures that the reactive power is < ±0.1%. The physical connection between the metering module and the MCU (microprocessor) is usually carried out through TXD (transmission data line) and RXD (reception data line); the baud rate is determined by setting relevant registers.

[0057] The MCU controls the serial port through programming to send instructions and receive data according to the set communication protocol. The metering module responds to the corresponding data packets. The MCU can be interrupted and woken up when it receives data or is ready to send data, thereby improving the real-time performance and efficiency of the system and avoiding the waste of MCU resources caused by frequent polling. In short, according to the interface specifications of the specific metering module and the functional characteristics of the MCU, the corresponding driver program and communication protocol stack are written to ensure the stable and reliable serial communication between the two.

[0058] Power management module: An efficient switching power supply system is adopted to output two isolated DC power supplies. One is used to supply power to the electricity meter itself, and the other is to provide DC power externally through the M-Bus interface. In this way, it can provide electrical energy for intelligent water meters, gas meters or other similar metering devices connected to the same M-Bus bus. This method simplifies installation and wiring, reduces system costs, and realizes unified management and control. The M-Bus interface, as a standard communication interface, is not only used for data transmission but also plays a role in power supply. This is because the M-Bus protocol stipulates the design principle of sharing power lines and data lines and supports the Bus-Powered mode. In this mode, the intelligent electricity meter, as the master device, can not only read the data of slave devices (such as intelligent water meters, gas meters, etc.) but also provide the power required for their operation. Usually, a buck chip is used to provide 3.3V or 5V DC power for the slave device system. In this way, the entire metering system can achieve integrated and intelligent management, enhance the reliability and convenience of the system, reduce operation and maintenance costs, and is conducive to building an intelligent energy management system in a smart city.

[0059] Storage module: The external memory uses an EEPROM (electrically erasable programmable read-only memory) and a FLASH memory. The MCU operates the EEPROM through the I2C bus; the MCU operates the FLASH through the SPI bus. The external memory is used to store electricity metering data, configuration information and other important parameters. The advantage of the EEPROM is that it can be erased and written multiple times and the data retention time is long, which is very suitable for recording cumulative electricity data. The FLASH is another type of non-volatile memory, which is characterized by fast read and write speed, stronger durability, and lower power consumption, and is suitable for application scenarios that require frequent reading and writing of data.

[0060] MCU (Microcontroller Unit): Select an MCU based on the ARM Cortex-M0+ core to design the smart electricity meter. ARM Cortex-M0+ is a low-power, high-performance microcontroller core suitable for embedded applications that are sensitive to power consumption and require a certain level of processing power. The maximum clock frequency of this MCU can reach 64 MHz. It has a relatively fast data processing speed and real-time response ability, and can efficiently coordinate and control each module inside the electricity meter, such as the metering module, communication module, storage module, etc. It realizes data exchange with remote servers or cloud platforms for operations such as remote meter reading, status monitoring, and software upgrade. It records the operating status, fault information, power consumption events, etc. of the electricity meter in real time and stores this data in non-volatile memory for future reference and analysis. According to the preset rate table and time period, it performs time-of-use billing and supports various billing strategies such as tiered electricity prices and peak-valley electricity prices. Considering data security and privacy protection, the MCU can integrate or implement data encryption algorithms through software to encrypt the electricity data during transmission and storage to ensure information security. According to instructions and preset conditions, it realizes intelligent control of the operating status of the electricity meter. The MCU based on the ARM Cortex-M0+ core provides powerful core processing capabilities for the smart electricity meter, meeting the design requirements of modern smart meters with multiple functions, high reliability, and low power consumption.

[0061] VI. Communication Interfaces: The smart electricity meter has diverse communication interfaces to meet the requirements of power management systems in different scenarios and at different levels. In addition to the M-Bus communication interface, there are also the following communication interfaces: 1. Infrared communication interface: mainly used for close-range device configuration, on-site data reading, and fault diagnosis. It does not require additional wiring and is simple and fast to operate. 2. RS-485 interface: This is a typical half-duplex multi-point communication bus, commonly used to build a local distributed measurement and control network. It can support multiple devices to communicate on a single bus, and the transmission distance and the number of communication nodes are relatively large. 3. Radio Frequency (RF) communication: Transmits data through radio waves and is suitable for remote meter reading and wireless networking scenarios. 4. The uplink communication module can be hot-swappable and optional: There is a PLC (Power Line Communication) that uses the power line for data transmission to realize the networking of devices inside the home or building, and can achieve real-time data transmission without additional wiring; GPRS / 4G / 5G communication module: Provides mobile network communication to realize remote data transmission, suitable for power management systems with a wide coverage range, and supports functions such as remote meter reading, remote monitoring, and fault alarm; NB-IoT (Narrowband Internet of Things): Designed specifically for low-power, high-connection-density scenarios, suitable for large-scale deployment of smart meters, with characteristics such as wide coverage, low power consumption, and low cost. Through these different communication interfaces, the smart electricity meter can flexibly access power management systems at all levels to realize diversified management requirements such as real-time data reporting, remote control, and fault alarm.

[0062] LCD and Buttons: The Liquid Crystal Display (LCD) indeed plays a crucial role in smart electricity meters. As the core component of the user interface, it can display various electricity parameters and relevant information in real-time, clearly, and intuitively. At the same time, smart electricity meters are equipped with buttons and keyboards for users to perform interactive operations, such as querying historical electricity consumption data, switching display pages, activating or deactivating the freeze state, and entering the electricity purchase password. The button design needs to be simple and clear, facilitating quick user understanding and operation, ensuring convenient access to electricity meter information and necessary control operations in daily use, and providing a more intuitive and user-friendly interaction experience.

[0063] Security Design: In the design of smart electricity meters, secure data transmission and accurate metering are indeed of utmost importance. A series of data encryption technologies and anti-stealing electricity design measures are taken at both the hardware and software levels: At the hardware level, a communication module with a relatively high security level is adopted to ensure the security of data during transmission; an anti-tampering and anti-unsealing packaging technology is used. Once the meter is illegally opened, the internal circuit will trigger a protection mechanism, record the tampering event, and may cause the meter to stop working; special protection measures are added to the current and voltage sampling circuits. For example, the current transformer adopts an anti-stealing electricity design to prevent illegal short-circuiting and bypass stealing of electricity; a secure data encryption algorithm is used to encrypt all data collected by the electricity meter. Whether stored locally or transmitted to a remote server, the privacy and integrity of the data are ensured. Through encrypted key management and authentication protocols, legitimate authentication is required to access electricity meter data, preventing unauthorized access and operations; a communication protocol with security functions is used to ensure that data is not intercepted and tampered with during transmission over the public network; an anomaly detection algorithm is implanted in the software to monitor the working status of the electricity meter and the reasonableness of metering data, and to promptly detect and record potential stealing electricity behaviors. Through a combination of software and hardware, smart electricity meters can achieve secure data transmission and accurate metering, ensuring the operational safety of the power system and a fair and just billing environment.

[0064] An intelligent electricity meter circuit with an M-Bus host communication interface realizes interconnection and interoperability with other energy metering devices such as water meters, gas meters, and heat meters through M-Bus bus technology. See Figure 3, the intelligent electricity meter circuit application of the M-Bus host communication interface. In this system, the intelligent electricity meter not only serves as its own electricity metering device but also acts as a data concentrator. The specific functions and working principles are as follows: 1. Electricity metering and data processing: The intelligent electricity meter first has the function of electricity metering, which can monitor and accurately measure the electricity consumption of users in real time, and at the same time perform data processing, such as time-of-use billing, power quality analysis, etc. 2. M-Bus master station function: The electricity meter integrates the M-Bus host communication interface and serves as the master station device of the M-Bus network, responsible for initiating communication, managing the network, receiving and forwarding data. 3. Data acquisition: Through the M-Bus bus, the electricity meter can communicate with slave devices such as water meters, gas meters, and heat meters connected to the same bus, and collect the metering data of these devices regularly or on demand according to the M-Bus protocol specification. 4. Power supply management: The M-Bus bus supports the "bus power supply" mode. In addition to its own electricity metering, the intelligent electricity meter can also provide DC power for the connected slave devices (such as water meters, gas meters, etc.) through the M-Bus interface, simplifying the system wiring and reducing the installation cost. 5. Data integration and storage: The various energy metering data collected by the electricity meter are integrated and processed internally, which may include data verification, error detection, data compression, etc., and then stored in non-volatile memory to ensure the integrity and reliability of the data. 6. Remote communication: In addition to M-Bus local communication, the intelligent electricity meter usually also has other remote communication capabilities, such as GPRS, LoRa, NB-IoT, PLC, etc., and uploads the integrated multi-meter data to the system master station, cloud server or energy management platform through these communication methods to achieve remote meter reading, data analysis and remote control. 7. Security protection and data encryption: To ensure data security, the electricity meter may adopt technologies such as encryption chips, secure communication protocols, and identity authentication mechanisms at the hardware and software levels to encrypt and protect the transmitted and stored data to prevent data from being stolen or tampered with. Through the above functions, it solves the factors of separately configuring power supplies for each meter or relying on energy storage devices such as batteries for power supply, reducing the maintenance cost and enabling each meter to operate stably for a long time; the data collected by each meter is uploaded to the system master station using the same transmission link, reducing the complexity of network construction and maintenance. This intelligent electricity meter circuit with an M-Bus host communication interface can realize the centralized monitoring and management of various energy consumptions, providing convenient and efficient energy data collection and analysis means for energy service providers, property management or users, supporting energy efficiency improvement, accurate cost settlement and intelligent energy management services.

[0065] In the field of smart meter technology, the present utility model proposes a technical solution for the circuit of a smart electricity meter that adopts an M-Bus host communication interface. The core of this technical solution lies in the design and implementation of a smart electricity meter that can not only perform its own electric energy metering task but also play multiple functions through the integrated M-Bus host communication interface. Specifically, this smart electricity meter has the following characteristics and advantages:

[0066] 1. Integrated power supply function: Through the M-Bus interface, the smart electricity meter can not only supply power to itself but also provide a stable DC power supply for other types of smart meters such as smart water meters, smart gas meters, or smart heat meters connected to it, thus saving the cost of independent wiring and realizing an integrated power supply solution for energy metering devices.

[0067] 2. Data interaction ability: The M-Bus bus protocol allows two-way data transmission on the communication line. The smart electricity meter uses the M-Bus host communication interface to be able to collect and upload the usage data of various smart meters to the background management system in real time, and at the same time, it can also receive instructions from the central system to realize multiple functions such as remote meter reading, rate adjustment, and fault alarm.

[0068] 3. System compatibility: Since M-Bus is an internationally recognized standard communication protocol, this smart electricity meter has good compatibility and expandability and can be easily connected to the smart grid and the Internet of Things system, which is conducive to building a comprehensive intelligent energy management system.

[0069] In summary, through the integration of M-Bus communication interface technology, this utility model has successfully developed a smart electricity meter that can act as both a power supply center and a data exchange hub, greatly improving the integration level and management level in the field of smart meters, and having significant significance for realizing the modernization of energy management in smart cities. In the attached drawings, only the main circuits are described, and conventional circuits such as keyboards and lighting are not exemplified. The processors involved are all existing components and can be achieved through the conventional operations of the processors.

[0070] The present utility model is fully described for a clearer disclosure, and the prior arts are not listed one by one.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present utility model, rather than to limit it; although the present utility model has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; as is obvious to those skilled in the art, multiple technical solutions of the present utility model can be combined. And these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present utility model. The technical content not elaborated in the present utility model is all well-known technology.

Claims

1. An intelligent electric energy meter circuit with an M-BUS host communication interface, characterized in that: It includes a host controller U4 and a physical layer interface connected to the host controller U4; the input end of the host controller MCU is electrically connected to a metering unit, a power management module, and a key module; The output end of the host controller U4 is electrically connected to an LCD display module, an indicator light, and a load switch; The host controller U4 is electrically connected to a host communication interface, an M-bus host communication interface unit, and an uplink module communication interface; The metering unit is electrically connected to a power module; The power module is electrically connected to a battery module; the power module and the battery module are electrically connected to the power management module.

2. The intelligent electric energy meter circuit of the M-BUS host communication interface according to claim 1, characterized in that: The power management module includes a rectifier D1, a power chip U1, a transformer RN1, and an optocoupler UN1; The power is divided into two paths through the rectifier D1; The first path passes through series resistors R3 and R15 and connects to the PRO channel through PRO; the second path is connected to the primary coil of the transformer RN1, and a diode is connected in series after a parallel capacitor C5 and resistor R4 between the primary coils of the transformer RN1; One path of the output end of the primary coil of the transformer RN1 is connected to SOURCE through the capacitor C13, and the second path is connected to pin 14 of the power chip U1; In the chip U1, pin 5 is connected to the PRO channel, pin 6 is connected to the optocoupler UN1, pin 9 is connected to SOURCE, and pin 3 is connected to the resistor R29; One end of the first secondary coil of the transformer RN1 is grounded, and the other end is connected to the resistor R29 after passing through a unit of a diode D12 in parallel after a series of resistor R26 and capacitor C21; The second secondary coil of the transformer RN1 is connected to SPN+, and the third secondary coil is connected to VCC for power supply; The optocoupler UN1 is connected to SPM+ for triggering the power chip U1.

3. The intelligent electric energy meter circuit of the M-BUS host communication interface according to claim 2, characterized in that: The power management module also includes an MCU system power supply, a clock power supply, and an interface power supply system; The MCU system power supply includes a chip UQ1; in the chip UQ1, pin 1 is connected to the VCC power supply, pin 1 is connected to the resistor RQ1 and then to pin 6, pin 6 outputs 3V3 through a filtering unit inductor LQ1 and capacitor C3; 3V3 is grounded through a zener diode EQ1; pin 3 is connected to 3V3 through the resistor RQ2; The interface power supply system includes a chip UQ2, and the input voltage SPM+ outputs +5V through the chip UQ2; The clock power supply includes a battery BAT1, one path of the battery BAT1 outputs 3V3 through a diode D11, and the other path outputs BAT ADC through a resistor R27.

4. The intelligent electric energy meter circuit of the M-BUS host communication interface according to claim 3, characterized in that: The uplink module communication unit includes a chip U5 and a chip U6, and the host controller U4 is connected to the interface RS1 through a series connection of the chips U5 and U6; The metering unit includes a metering pulse output unit, including metering unit chips UO1 and UO2; the metering unit chips UO1 and UO2 are respectively connected to channels PF and QF, and the output is connected to the JO1 interface; The M-bus host communication interface unit includes optocouplers U9 and U10, and a chip U7; the optocouplers U9 and U10 are connected to the corresponding channels of the host controller U4; the optocoupler U9 is connected to the chip U7, and the chip U7 is connected to the interface J2; The optocoupler U10 is connected to the interface J2 through a two-stage control triode group Q11 and Q12.

5. The intelligent electric energy meter circuit of the M-BUS host communication interface according to claim 4, characterized in that: The host controller U4 is connected to a magnetic field detection system, and the magnetic field detection system includes a chip U8 electrically connected to the host controller U4 to detect the influence of the magnetic field on the circuit; The metering unit includes chip U15; chip U15 is connected to the 3V3 voltage, and chip U15 is electrically connected to the host controller U4.

6. The intelligent electric energy meter circuit of the M-BUS host communication interface according to claim 5, characterized in that: The metering unit is electrically connected to a current sampling circuit and a voltage sampling circuit; In the current sampling circuit, there are I+ and I- acquisition terminals. The I+ acquisition terminal is divided into two paths. One path is grounded through resistor R85, and the other path is connected to resistor R77. The output terminal of resistor R44 is respectively connected to chip U15 and grounded through capacitor C55; The I- acquisition terminal is divided into two paths. One path is grounded through resistor R91, and the other path is connected to resistor R93. The output terminal of resistor R93 is respectively connected to chip U15 and grounded through capacitor C58; In the voltage sampling circuit, the voltage terminal UN is divided into two paths through resistor R74; one path is connected to the VLP of chip U15, and the other path is grounded after being connected in parallel with resistor R75 and capacitor C51. The VLN of chip U15 is grounded through resistor R86 and capacitor C57 connected in parallel.

7. The intelligent electric energy meter circuit of the M-BUS host communication interface according to claim 6, characterized in that: The host controller U4 is electrically connected to a load switch control detection circuit; The load switch control detection circuit includes relay WJ and a coil control circuit electrically connected to relay WJ; The coil control circuit includes chip U13 and optocoupler U14 respectively electrically connected to the host controller U4; Chip U13 and optocoupler U14 are respectively electrically connected to relay WJ; The load switch control detection circuit is electrically connected to the metering unit; the metering unit is electrically connected to relay WJ; The host controller U4 is also electrically connected to an infrared communication interface and a radio frequency communication interface; The button module includes a liquid crystal display screen and buttons.

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