Big Dipper positioning-based dual-mode communication operation and maintenance system

Abstract

The invention discloses a dual-mode communication operation and maintenance system based on Beidou positioning, and relates to the field of power system operation and maintenance, and the system comprises a strong and weak current interface module, a power management module, a dual-mode MCU chip, a signal processing module and a Beidou positioning module. The strong and weak current interface module is used for realizing energy interaction and information interaction between the dual-mode communication operation and maintenance system and an external environment; the power management module is used for providing stable power; the dual-mode MCU chip is used for controlling dual-mode switching and data transmission of power line carrier communication and wireless radio frequency communication and processing positioning information uploaded by the Beidou positioning module; the signal processing module is used for performing transmitting amplification, receiving filtering, matched filtering and transmitting-receiving switching on the power line carrier signal and the radio frequency signal; the Beidou positioning module is used for receiving Beidou satellite positioning information and sending the positioning information to the dual-mode MCU chip. The technical problems of time and labor consumption, poor accuracy, dependence on an overseas positioning system and the like of a low-voltage transformer area operation and maintenance method are solved.

Description

A dual-mode communication operation and maintenance system based on BeiDou positioning Technical Field

[0001] This invention relates to the field of power system operation and maintenance technology, and in particular to a dual-mode communication operation and maintenance system based on BeiDou positioning. Background Technology

[0002] With the rapid expansion of power system construction, the structure of low-voltage distribution lines is becoming increasingly complex. Frequent line changes due to the addition, cancellation, and relocation of low-voltage users make the operation and maintenance of low-voltage distribution areas exceptionally difficult. The attribution relationships of low-voltage distribution network areas within the system are often incomplete or incorrect. This leads to chaotic management of meter equipment assets, abnormal line loss calculations, difficulties in fault diagnosis and location, and unbalanced three-phase loads. Traditional methods for distribution area operation and maintenance mainly include the following:

[0003] 1) Manual Inspection and Maintenance: Currently, inspection scenarios mainly fall into two categories: one is overhead line areas, primarily in rural power grid areas, where the relationships between substations can be clarified through manual inspection due to the clearly visible overhead lines; the other is buried line areas, primarily in urban power grid areas, where manual inspection is difficult due to the underground location of the cables. Manual inspection is not only time-consuming and labor-intensive but also prone to errors, making it difficult to meet the requirements of real-time performance and accuracy.

[0004] 2) Instantaneous power outage maintenance: When the lines are complex, power outages can be used to confirm the relationship between transformer substations. However, power outages not only affect the user's electricity experience, but also make it difficult to carry out power outages in certain specific situations, such as key users like factories or hospitals.

[0005] 3) Identification and maintenance method based on electrical signal distortion: It is suitable for power supply areas with short power supply radius and relatively stable load. It has a high identification accuracy, but the equipment is difficult to miniaturize, and signal distortion poses a risk to power supply quality and reliability.

[0006] 4) GPS-based operation and maintenance: Although GPS positioning serves the world, its accuracy is relatively low. Furthermore, the power industry is a matter of national security. Because the GPS system is controlled by the United States and can be jammed against civilian signals, national infrastructure security is completely dependent on others, which is detrimental to social and economic stability.

[0007] Therefore, given the shortcomings of existing low-voltage distribution area operation and maintenance methods, such as being time-consuming and labor-intensive, having poor accuracy, affecting users' electricity experience, posing safety hazards, and relying on overseas positioning systems, it is necessary to provide a system that can achieve high-precision positioning and efficient communication of electricity meter equipment. Summary of the Invention

[0008] This invention provides a dual-mode communication operation and maintenance system based on BeiDou positioning, which can solve the technical problems of existing low-voltage distribution area operation and maintenance methods, such as being time-consuming and labor-intensive, having poor accuracy, affecting user power experience, posing safety hazards, and relying on overseas positioning systems. The technical solution is as follows:

[0009] In a first aspect, embodiments of the present invention provide a dual-mode communication operation and maintenance system based on BeiDou positioning, comprising: a strong and weak current interface module, a power management module, a dual-mode MCU chip, a signal processing module, and a BeiDou positioning module;

[0010] The strong and weak current interface module is used to realize energy interaction and information interaction between the dual-mode communication operation and maintenance system and the external environment.

[0011] The power management module is connected to the strong and weak current interface module and is used to provide a stable power supply for the dual-mode MCU chip, signal processing circuit and Beidou positioning module.

[0012] The dual-mode MCU chip is connected to the signal processing circuit and the Beidou positioning module respectively, and is used to control the dual-mode switching and data transmission of power line carrier communication and wireless radio frequency communication, and to process the positioning information uploaded by the Beidou positioning module.

[0013] The signal processing module is used to transmit and amplify, receive and filter, match filter and switch transmit and receive power line carrier signals and radio frequency signals.

[0014] The BeiDou positioning module is used to receive BeiDou satellite positioning information and send the positioning information to the dual-mode MCU chip.

[0015] In some embodiments of the present invention, the high-voltage and low-voltage interface module includes a low-voltage interface and a high-voltage interface;

[0016] The low-voltage interface is used to connect and communicate with the electricity meter and obtain the electricity meter's operating power.

[0017] The high-voltage interface is used to couple carrier signals to the power line.

[0018] In some embodiments of the present invention, each signal line of the low-voltage interface includes an RC protection circuit; each RC protection circuit includes a series resistor and a parallel capacitor.

[0019] In some embodiments of the present invention, the power management module includes a DC-DC circuit and an LDO circuit;

[0020] The DC-DC circuit is used to step down and convert the input voltage provided by the meter to obtain a converted voltage value.

[0021] The LDO circuit is connected to the output of the DC-DC circuit and is used to regulate the converted voltage value to obtain a stable voltage, which is then provided to the dual-mode MCU chip, the signal processing circuit, and the Beidou positioning module.

[0022] In some embodiments of the present invention, the signal processing module includes an HPLC signal processing circuit and an HRF signal processing circuit;

[0023] The HPLC signal processing circuit is connected between the dual-mode MCU chip and the high-voltage interface, and is used to transmit, amplify and receive the original carrier signal emitted by the dual-mode MCU chip.

[0024] The HRF signal processing circuit is connected between the dual-mode MCU chip and the antenna, and is used to perform matched filtering and transmit / receive switching on the radio frequency signal transmitted by the dual-mode MCU chip.

[0025] In some embodiments of the present invention, the HPLC signal processing circuit includes a carrier transmission amplification circuit and a carrier signal coupling and receiving filtering circuit;

[0026] The carrier transmission amplification circuit includes a carrier power amplification chip, which is used to amplify the power of the carrier signal output by the dual-mode MCU chip;

[0027] The carrier signal coupling and receiving filtering circuit includes a coupling transformer, a filtering network, and a clamping protection circuit, used to couple the amplified carrier signal to the power line and filter out out-of-band noise from the carrier signal received from the power line.

[0028] In some embodiments of the present invention, the HRF signal processing circuit includes a radio frequency switch, a matching inductor, and a filter capacitor;

[0029] The matching inductor and filter capacitor form an RF matching network, which is used for impedance matching and out-of-band noise suppression of RF signals.

[0030] The radio frequency switch is used to control the switching of the radio frequency signal transmission and reception paths.

[0031] In some embodiments of the present invention, the dual-mode MCU chip is a dual-mode communication chip that supports broadband power line carrier and Sub-GHz wireless transceiver functions.

[0032] In some embodiments of the present invention, the BeiDou positioning module includes a power decoupling capacitor, a serial port signal RC filter, and an electrostatic discharge protection tube.

[0033] In some embodiments of the present invention, an early warning unit is also included, which is used to detect the meter displacement threshold through a dual-mode MCU module and report the position offset data through a signal processing module.

[0034] The beneficial effects of the technical solutions provided by some embodiments of the present invention include at least the following: By integrating a strong and weak current interface module, a power management module, a dual-mode MCU chip, a signal processing module, and a Beidou positioning module; based on the high-precision positioning of the Beidou positioning module and the combination of dual-mode communication, real-time acquisition and transmission of meter location information and electricity consumption data are realized, improving the efficiency of equipment asset management, fault diagnosis, inspection and patrol, power outage repair and other operation and maintenance work, and reducing the workload of operation and maintenance personnel. Furthermore, by adopting a standardized strong and weak current interface design module, it achieves plug-and-play compatibility with the vast majority of existing electricity meters, eliminating the need for large-scale modification of existing electricity meter equipment, significantly reducing the implementation difficulty and promotion cost of the solution; and the integrated system is applicable to different types of low-voltage distribution areas such as overhead line distribution areas and underground line distribution areas, while also being able to cope with emergency scenarios of conventional communication interruptions, solving the problem of limited applicability of existing operation and maintenance methods. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 is a system architecture diagram of an embodiment of the dual-mode communication operation and maintenance system based on Beidou positioning provided by the present invention;

[0037] Figure 2 is a schematic diagram of an embodiment of the dual-mode communication operation and maintenance system based on Beidou positioning provided by the present invention;

[0038] Figure 3 shows the strong and weak current interface circuit of the present invention;

[0039] Figure 4 shows the DC-DC power supply circuit of the present invention;

[0040] Figure 5 shows the LDO power supply circuit of the present invention;

[0041] Figure 6 shows the carrier signal processing circuit of the present invention;

[0042] Figure 7 shows the carrier transmission amplifier circuit of the present invention;

[0043] Figure 8 shows the radio frequency matching circuit of the present invention;

[0044] Figure 9 shows the dual-mode MCU peripheral circuit of the present invention;

[0045] Figure 10 shows the circuit diagram of the Beidou positioning module of the present invention. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0047] The following will describe in detail the dual-mode communication operation and maintenance system based on BeiDou positioning provided in the embodiments of this application, with reference to Figure 1. Please refer to Figures 1 and 2, which provide a schematic diagram of the architecture of a dual-mode communication operation and maintenance system based on BeiDou positioning according to an embodiment of this application. As shown in Figure 1, the system of this embodiment includes: a strong and weak current interface module 11, a power management module 12, a dual-mode MCU chip 13, a signal processing module 14, and a BeiDou positioning module 15;

[0048] The strong and weak current interface module 11 is used to realize energy interaction and information interaction between the dual-mode communication operation and maintenance system and the external environment;

[0049] It should be noted that the external environment mainly refers to external devices such as electricity meters, including but not limited to electricity meters and electrical equipment. Energy interaction refers to the interaction of electrical energy with electricity meters or the power grid, while information interaction refers to the interaction of local data communication with smart meters and the reading of electricity consumption data.

[0050] The power management module 12 is connected to the strong and weak current interface module and is used to provide a stable power supply for the dual-mode MCU chip, signal processing circuit and Beidou positioning module.

[0051] The dual-mode MCU chip 13 is connected to the signal processing circuit and the Beidou positioning module respectively, and is used to control the dual-mode switching and data transmission of power line carrier communication and wireless radio frequency communication, and to process the positioning information uploaded by the Beidou positioning module.

[0052] It should be noted that a dual-mode MCU chip refers to a microcontroller chip that integrates a complete hardware system of two communication methods (power line carrier and radio frequency). The chip uses an internal communication module to switch between power line carrier (PLC) communication and radio frequency (RF) communication, and can automatically select the optimal communication method according to changes in the actual communication environment, ensuring the stability and efficiency of data transmission. The chip can monitor the communication quality (such as signal strength and bit error rate) of both power line carrier and radio frequency channels in real time. When the quality of one channel deteriorates, the system automatically switches the data to the other channel with better quality for transmission, ensuring the reliability of data transmission. The signal processing module 14 is used for transmitting amplification, receiving filtering, matched filtering, and transmitting / receiving switching of the power line carrier signal and the radio frequency signal.

[0053] It should be noted that, in one specific embodiment, the signal processing module 14 includes an HPLC signal processing circuit and an HRF signal processing circuit;

[0054] The HPLC signal processing circuit is connected between the dual-mode MCU chip and the high-voltage interface, and is used to transmit, amplify and receive the original carrier signal emitted by the dual-mode MCU chip.

[0055] The HRF signal processing circuit is connected between the dual-mode MCU chip and the antenna, and is used to perform matched filtering and transmit / receive switching on the radio frequency signal transmitted by the dual-mode MCU chip.

[0056] It should be noted that in a network composed of multiple modules, some modules can act as proxy coordinating nodes (PCOs) while simultaneously using HRF and HPLC. They can receive wireless signals from one direction and then forward them to the other direction via power lines, or vice versa, physically forming a hybrid power line + wireless mesh network, which greatly enhances the network's coverage and robustness.

[0057] The BeiDou positioning module 15 is used to receive BeiDou satellite positioning information and send the positioning information to the dual-mode MCU chip.

[0058] It should be noted that this application integrates the BeiDou module into the dual-mode communication and maintenance module, combined with the existing HPLC+HRF dual-mode communication method, to achieve high-precision positioning and efficient communication for electricity meter equipment. The BeiDou module is integrated into the dual-mode communication and maintenance module, which is plugged into the electricity meter. This allows for real-time acquisition of geographical information such as latitude, longitude, and altitude of the meter's installation location, thereby replacing traditional manual recording and realizing digital and spatially visualized management of electricity meter assets.

[0059] In this embodiment, by integrating a strong and weak current interface module, a power management module, a dual-mode MCU chip, a signal processing module, and a BeiDou positioning module, and combining the high-precision positioning of the BeiDou positioning module with dual-mode communication, real-time acquisition and transmission of meter location information and electricity consumption data are achieved. This improves the efficiency of equipment asset management, fault diagnosis, inspection and patrol, and power outage repair, while reducing the workload of maintenance personnel. Furthermore, the standardized strong and weak current interface design module enables plug-and-play compatibility with most existing electricity meters, eliminating the need for large-scale modifications to existing meter equipment and significantly reducing the implementation difficulty and promotion cost of the solution. The integrated system is applicable to different types of low-voltage distribution areas, such as overhead line areas and underground line areas, and can also handle emergency scenarios involving communication interruptions, solving the problem of limited applicability of existing maintenance methods.

[0060] In some embodiments of the present invention, the high-voltage and low-voltage interface module includes a low-voltage interface and a high-voltage interface;

[0061] The low-voltage interface is used to connect and communicate with the electricity meter and obtain the electricity meter's operating power.

[0062] The high-voltage interface is used to couple carrier signals to the power line.

[0063] It should be noted that the strong and weak current interface circuits are shown in Figure 2. The weak current interface is mainly used for communication with the electricity meter and to obtain power from the meter. The strong current interface is mainly used for carrier coupling communication, providing a transmission medium channel for carrier communication. Each signal line on the weak current interface has an RC (resistor-capacitor) protection circuit, which can effectively prevent damage to the dual-mode chip caused by static electricity and transient impacts that may occur during hot-plugging. Among them, R1, R2, R3, R4, and R5 are series current-limiting protection resistors, and C1, C2, C3, C4, and C5 are parallel filter capacitors.

[0064] As shown in Figure 3, the high-voltage and low-voltage interface circuit consists of pins that connect to the electricity meter. The low-voltage interface is mainly used for communication with the electricity meter and to obtain power from it. The high-voltage interface is mainly used for carrier-coupled communication, providing a transmission medium channel for carrier communication. The signal flow of the low-voltage interface is as follows: 12V power flows into the low-voltage interface to power the subsequent DC-DC converter, with C44 connected in parallel to ground (GND) to filter out power ripple and provide a clean DC voltage; RXD-PLC is the serial port receive signal from the electricity meter to the module via the low-voltage interface, which is filtered by an RC filter composed of resistor R5 and capacitor C5 and then sent to the module MCU, connected to the RXD pin of the MCU; RST-PLC is the reset signal from the electricity meter to the module via the low-voltage interface, which is filtered by an RC filter composed of resistor R3 and capacitor C3 and then sent to the module MCU, connected to the RST pin of the MCU. Pins: EVENT-PLC is the event reporting signal from the meter to the module via the low-voltage interface. After being filtered by an RC filter composed of resistor R2 and capacitor C2, it is sent to the module MCU and connected to the EVENT pin of the MCU; STA is the status signal from the module MCU to the meter. After being filtered by an RC filter composed of resistor R4 and capacitor C4, it is sent to the low-voltage interface and connected to the STA-PLC pin of the meter; TXD is the serial port transmission signal from the module MCU to the meter. After being filtered by an RC filter composed of resistor R1 and capacitor C1, it is sent to the low-voltage interface and connected to the TXD-PLC pin of the meter.

[0065] In some embodiments of the present invention, the power management module includes a DC-DC circuit and an LDO circuit;

[0066] The DC-DC circuit is used to step down and convert the input voltage provided by the meter to obtain a converted voltage value.

[0067] The LDO circuit is connected to the output of the DC-DC circuit and is used to regulate the converted voltage value to obtain a stable voltage, which is then provided to the dual-mode MCU chip, the signal processing circuit, and the Beidou positioning module.

[0068] It's important to note that DC-DC converters are used for high-efficiency voltage conversion. They significantly step down the relatively high input voltage from the meter to an intermediate voltage, but the output power supply contains high-frequency ripple and noise due to switching operations, resulting in relatively poor voltage accuracy and transient response. Therefore, combining it with an LDO linear regulator provides high-precision linear regulation, stably adjusting the voltage to a very accurate value while filtering out high-frequency noise from the preceding stage. The DC-DC + LDO architecture combines the advantages of both: the DC-DC converter handles most of the voltage conversion with low power loss, ensuring high overall system efficiency. The LDO then refines the DC-DC output, providing the necessary clean power to sensitive circuits. Furthermore, the LDO itself, due to its small input-output voltage difference, keeps its power consumption and heat generation within acceptable limits. This clean power supply significantly reduces the risk of errors in analog circuits and digital cores due to power interference, ensuring the stability of communication and positioning.

[0069] As shown in Figure 4, the DC-DC converter circuit uses a power input to power the chip. Two parallel electrolytic capacitors, C6 and C7, have their positive terminals connected to 12VP and their negative terminals grounded (GND). Their function is to filter low-frequency ripple and high-frequency noise from the input power line and to store energy for the chip's instantaneous high current demands. The filtered 12VP is directly connected to the VIN pin of chip U1, powering the chip's internal control circuitry and switching transistors. The chip's EN pin is pulled high to 12VP through a resistor. The chip's SW pin is the output node of the internal switching transistor, which switches rapidly under chip control. One end of the L1 power inductor is connected to the SW pin, and the other end is connected to the 3V3 output terminal. When SW is high, current flows through L1 and charges the load and output capacitor, storing energy in the inductor. When SW is low, the inductor releases energy, and the current continues to flow to the load through a freewheeling diode (usually integrated inside U1). C11 and C10 are the main output filter capacitors, with their positive terminals connected to the 3V3 output terminal and their negative terminals grounded. Together with L1, it smooths the pulse voltage output from the SW pin into a stable DC voltage. C9 is a bootstrap capacitor connected between the VBST and SW pins. To efficiently drive the high-side N-channel MOSFET switch inside the chip, its gate voltage needs to be higher than its source (SW) voltage. When SW is low, the internal circuitry of U1 charges C9 from the VREG power supply through a diode. When driving the high-side transistor, the charge stored in C9 is released, providing a voltage higher than SW to the drive circuit, ensuring the switch is fully turned on and reducing losses. R8 and R9 form a precision voltage divider network. The 3V8 output voltage is divided by R8 and R9, resulting in a sampling voltage proportional to the output voltage at their junction. Different output voltages can be obtained by adjusting different resistor values. The VREG pin is the output of the chip's internal low-dropout linear regulator, typically providing a fixed voltage (such as 3.3V or 5V) to power the internal analog circuitry. C12 is a bypass / decoupling capacitor for the VREG lead, connected between VREG and GND to stabilize this power supply path. The SS pin is the soft-start control pin, grounded through a capacitor (C10). Upon power-up, a small internal current source supplies current to C8, causing the voltage on the SS pin to rise slowly. The internal control circuitry causes the switching current limit or reference voltage to increase as the SS voltage rises, thus achieving a smooth output voltage build-up and avoiding input inrush current and output voltage overshoot during startup. R7 and R6 are enable voltage divider resistors. One end of R7 is connected to 12Vp, and the other end is connected to the EN pin of the power supply chip. One end of R6 is connected to the EN pin of the power supply chip, and the other end is grounded. Adjusting the voltage divider value sets the output enable power supply of the power supply chip.

[0070] As shown in Figure 5, the LDO circuit uses the 3V8 DC voltage generated by the DC-DC circuit as its input power supply. C12 and C13 are connected in parallel at the input of U2, with one end connected to the VIN pin of U2 and the other end connected to ground (GND). C12 is used to filter out low-frequency ripple on the input power line and provide energy storage for instantaneous load changes of the LDO. C13 is used to filter out high-frequency noise on the input power supply and suppress interference introduced by wiring, providing high-frequency bypass for the LDO. The low dropout linear regulator chip VIN (power input pin) receives the voltage from 3V8 and filtered by C12 / C13, GND (ground pin) is connected to system ground, and VOUT (power output pin) outputs a stable and clean 3.3V voltage. C14 and C15 are connected in parallel at the output of U2, with one end connected to the VOUT pin of U2 and the other end connected to ground. C14 further smooths the output voltage and suppresses low-frequency fluctuations. C15 suppresses high-frequency noise generated by the LDO itself, improves the transient response of the load, and ensures high-frequency stability. The circuit diagrams on the right and bottom of Figure 5 are similar, providing output energy storage, low-frequency filtering, and high-frequency decoupling and noise suppression. LDOs provide extremely low ripple and noise power, making them particularly suitable for powering modules sensitive to power supply noise, such as the core of dual-mode MCU chips, DDR interfaces (1.8V), or high-speed analog circuits. Each LDO's input and output terminals are equipped with a "one large, one small" parallel capacitor combination for power supply decoupling. The large capacitor handles the low-frequency range, and the small capacitor handles the high-frequency range, ensuring sufficiently low power supply impedance across the entire frequency range. The two LDO circuits are independent and can power different loads separately, avoiding crosstalk between the digital core and I / O circuits and improving system stability.

[0071] In some embodiments of the present invention, the signal processing module includes an HPLC signal processing circuit and an HRF signal processing circuit;

[0072] The HPLC signal processing circuit is connected between the dual-mode MCU chip and the high-voltage interface, and is used to transmit, amplify and receive the original carrier signal emitted by the dual-mode MCU chip.

[0073] The HRF signal processing circuit is connected between the dual-mode MCU chip and the antenna, and is used to perform matched filtering and transmit / receive switching on the radio frequency signal transmitted by the dual-mode MCU chip.

[0074] In one specific embodiment, the HPLC signal processing circuit includes a carrier transmission amplification circuit and a carrier signal coupling and receiving filtering circuit;

[0075] The carrier transmission amplification circuit includes a carrier power amplification chip, which is used to amplify the power of the carrier signal output by the dual-mode MCU chip;

[0076] The carrier signal coupling and receiving filtering circuit includes a coupling transformer, a filtering network, and a clamping protection circuit, used to couple the amplified carrier signal to the power line and filter out out-of-band noise from the carrier signal received from the power line.

[0077] As shown in Figure 6, in the carrier signal processing circuit, R11 is connected in parallel at the signal input terminal. Its main functions are impedance matching and current limiting, reducing signal reflection and limiting the current flowing into subsequent circuits. D1 and D2 are clamping protection diodes, clamping the voltage of the SSCIN signal relative to ground within the forward voltage drop range of the diodes (e.g., ±0.7V), preventing excessive static electricity or transient voltage from entering from the signal line and protecting the subsequent communication chip. The two parallel capacitors C23 and C24, with one end connected to the common point of D1 / D2 (or the signal line) and the other end grounded, form a low-pass filter. Together with components such as R11, they filter out high-frequency noise outside the carrier frequency band, making the signal cleaner. Using parallel capacitors reduces the equivalent series inductance, improving the high-frequency filtering effect. L3, together with C23 / C24, forms an LC filter network, further enhancing the suppression capability for noise outside the specific frequency band. The capacitors C21 and C22 connected to L3 are also part of the filter network, ensuring that the impedance seen from the communication chip is optimal at the carrier frequency while blocking signals of non-carrier frequencies. T1 is a coupling transformer connected to the aforementioned filter network (L3, C21, C22, etc.), transmitting signals through magnetic coupling and achieving electrical isolation between the primary (equipment side) and secondary (power grid side). This allows for better matching of the output impedance of the communication circuit with the characteristic impedance of the power line, improving signal transmission efficiency. L2 is connected in series in the carrier receiving path, presenting high impedance to high-frequency signals to ensure effective reception of the carrier signal. C20 is a high-voltage safety capacitor connected in series with the live wire L, forming an LC filter with the primary inductance of the coupling transformer T1. It is mainly used to filter out power frequency signals, providing a low-impedance path for high-frequency carrier signals between L and N, enabling differential transmission of signals on the power line and enhancing anti-interference capabilities. TVS1 is a transient suppression diode connected in parallel across the weak current winding of transformer T1. When the line is subjected to high-voltage surges caused by lightning strikes, inductive load switching, etc., TVS1 can quickly break down and conduct, dissipating the surge energy and thus protecting transformer T1 and subsequent communication circuits from high-voltage breakdown. Resistor R10 is connected in parallel to the weak current side of transformer T1 or in series in the circuit. Its main function is damping and matching; it can absorb some reflected signals, prevent signal oscillation at the transformer ports, and make the circuit characteristics more stable. C25 is connected to the neutral (N) line or used as a DC blocking capacitor to filter out the DC component on the carrier received signal.

[0078] As shown in Figure 7, the carrier transmission amplifier circuit is powered by the 12V output from the power management module, directly connected to the Vddb and Vdda pins of the chip. C30 is a power supply decoupling capacitor connected between the Vddb pin and ground (GND) to filter out high-frequency noise on this power supply path, providing transient large current to the chip and ensuring the stability of the output stage. C49 is another power supply decoupling capacitor connected between the Vdda pin and ground (GND) to provide a clean and stable voltage to the internal analog small-signal processing circuits (such as the preamplifier and bias circuits) of the chip. SSC_ON / OFF is the digital control signal of the main control chip (such as a dual-mode MCU), connected to the En pin of the chip through resistor R12. When this signal is high, the chip U4 is enabled and starts working; when it is low, the chip enters shutdown or low-power mode, realizing energy saving and silent control of communication. A+ and A- are differential carrier signal pairs from the main control chip. Components R14, R15, C26, and C27 together form the input matching and filtering network. They are typically connected symmetrically between the two differential input terminals A+ and A-, and between the input terminals and Vmid (internal reference midpoint voltage) or ground. Their function is to match the output impedance of the main control chip with the input impedance of the power amplifier chip, achieving maximum power transfer and reducing signal reflection. The differential-to-single-ended converter / filter works in conjunction with the internal circuitry to convert the single-ended input signal into a differential signal processed internally by the chip, and filters out out-of-band noise. The Vmid midpoint reference voltage generated internally by the chip is typically half the power supply voltage (e.g., 6V). It is filtered by a capacitor to provide a stable DC bias point for the input stage, ensuring that the AC signal is amplified at its optimal operating point. SEND is the chip's final power output pin, from which the high-power carrier signal, after internal multi-stage amplification, is output. R17 is the output series resistor, which limits the maximum current flowing out of the chip to prevent damage in case of a short circuit or abnormality. Together with the inductance and distributed capacitance of the subsequent coupling transformer, it adjusts the impedance characteristics of the output network, suppressing potential resonance peaks and making the output flatter and more stable. SSCOUT_A is the carrier power amplification input signal. C26, C27, R14, and R15 form the input matching network. R16 is the feedback resistor, connected in parallel with C28 to form a low-pass filter. The amplification factor is adjusted by the ratio of R16 / R15. C29 is the DC blocking capacitor at the carrier amplification output, filtering out the DC component of the carrier signal.

[0079] Therefore, the carrier amplifier (PA) chip amplifies the received analog signal, giving it enough energy to be transmitted through the power line, while overcoming interference from line noise, attenuation, and impedance changes, ensuring reliable signal transmission to the receiving end.

[0080] In some embodiments of the present invention, the HRF signal processing circuit includes a radio frequency switch, a matching inductor, and a filter capacitor;

[0081] The matching inductor and filter capacitor form an RF matching network, which is used for impedance matching and out-of-band noise suppression of RF signals.

[0082] The radio frequency switch is used to control the switching of the radio frequency signal transmission and reception paths.

[0083] As shown in Figure 8, the RF matching circuit uses an HRF antenna for transmitting and receiving radio frequency signals (UHF band). A TVS3 transient voltage suppressor diode is connected between the antenna feed point and ground (GND) to discharge instantaneous high-voltage surges introduced by static electricity, lightning strikes, etc., protecting the extremely expensive RF chip from damage. An L6 RF anti-current coil / inductor is connected in series in the antenna path, providing a DC path for the RF signal. Together with a capacitor, it forms a matching network, blocking high-frequency noise from entering the power supply from the antenna end. A C31 DC blocking / coupling capacitor is connected in series in the antenna signal path, blocking the DC component and allowing only AC RF signals to pass through. It also participates in impedance matching. The core RF switch / filter chip (U5) switches the signal path between transmit (TX) and receive (RX) modes. VC1 and VC2 control voltage pins are connected to the MCU, which controls the RF switch to determine whether to enable wireless reception or transmission. GND is the ground pin of the chip. RF signal input pins are also shown. When the control logic of VC1 and VC2 is 0 or 1, the switching pins RFC and OUT1 of the RF switch are connected, the wireless signal is in receive mode, and the signal is sent from the antenna to the RFI direction, which is connected to the MCU. When the control logic of VC1 and VC2 is 1 or 0, the switching pins RFC and OUT2 of the RF switch are connected, the wireless signal is in transmit mode, the signal is sent from the RFO to the antenna, and the RFO is connected to the MCU. Simultaneously, in receive mode, the signal from the antenna also enters the chip through this path and is output from the RFI to the subsequent stage. C37 acts as DC blocking and impedance matching. L9 and C4 form an LC matching network. L9 (inductor) and C4 (capacitor) are connected in a specific form (usually a parallel capacitor C4 to ground and a series inductor L9) to perform conjugate matching with the chip's output impedance and the input impedance of the subsequent power amplifier, enabling RF power to be transmitted with maximum efficiency. After matching, the signal is sent to the direction marked RFO. VDDRF_PA is "RF power amplifier power supply," indicating that the matched signal will enter a power amplifier (PA) for amplification before finally being sent to the antenna for transmission through the switch. In the receiving path (RX Path - connected to OUT2), the signal is output from the OUT2 pin of U5 (during reception), and C36 acts as DC blocking and impedance matching. L4, C33, and C34 form a more complex LC filter matching network to filter out interference signals outside the operating frequency band (such as image frequencies and out-of-band noise) and simultaneously complete impedance matching. After matching, the signal is sent to the direction marked RFO. RFO usually stands for "RF Input / Output 0". VDDRF_PA is the power rail supplying the RF power amplifier (PA). To ensure stability under high current, good decoupling is usually required. L7 and C32 constitute the power supply decoupling network. L7 is a ferrite bead or a large inductor used to isolate noise from the digital power supply; C32 is a large-capacity capacitor used to store energy and filter low-frequency noise. Together, they provide a clean and stable power supply for the PA.

[0084] Therefore, the HRF signal processing circuit of this application is mainly responsible for filtering the radio frequency signal to ensure that the gain, attenuation, matching, and other indicators of the radio frequency signal meet the requirements during processing, thereby achieving efficient and stable radio frequency signal transmission. Because the dual-mode MCU chip integrates the radio frequency circuit internally, only a simple external matching circuit is needed to achieve wireless communication.

[0085] In some embodiments of this invention, the dual-mode MCU chip uses the self-developed dual-mode communication chip WTZ32, and the peripheral circuit of the chip is shown in Figure 9. WTZ32 is a highly integrated, cost-effective dual-mode chip that supports broadband power line carrier and SubG wireless transceiver. It integrates a 32-bit CPU, SRAM and ROM, rich peripheral interfaces (I2C, GPIO, UART, SPI, PWM, PSRAMC), OFDM-based PLC PHY and RF PHY, high-performance PLC analog front-end and RF analog front-end, watchdog timer, counter, clock and reset modules, and supports two LVD inputs. It is suitable for smart meters, remote meter reading devices, smart homes, charging stations, and energy management systems.

[0086] In some embodiments of the present invention, the BeiDou positioning module circuit is shown in Figure 10. The BeiDou positioning module is connected to an external GNSS antenna. The GNSS codec chip performs encoding and decoding of relevant positioning information. The positioning information is then transmitted to the main MCU module via serial communication. The main MCU module performs protocol conversion, converting the positioning information obtained from the GNSS codec chip into the extended DL / T645-2007 protocol, and then transmits it to an external system via serial communication. U6 is the BeiDou module; C39 and C40 are power supply decoupling capacitors used to filter out power supply noise; R21 and C41 are protection devices for the RST signal, preventing external interference from causing abnormal module reset; R19 and C42 are protection devices for the TX signal; R20 and C4 are protection devices for the RX signal; and the RC circuit forms a filter to prevent interference with the serial port signal; R18 is a BeiDou wireless signal debugging resistor; and TVS4 is an electrostatic discharge protection diode to prevent electrostatic damage to the BeiDou module.

[0087] It also includes an early warning unit, which is used to detect the meter displacement threshold through the dual-mode MCU module and report the position offset data through the signal processing module.

[0088] The above description discloses only preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A dual-mode communication operation and maintenance system based on BeiDou positioning, characterized in that, include: Strong and weak current interface module, power management module, dual-mode MCU chip, signal processing module and Beidou positioning module; The strong and weak current interface module is used to realize energy and information interaction between the dual-mode communication operation and maintenance system and the external environment; the power management module is connected to the strong and weak current interface module and is used to provide stable power to the dual-mode MCU chip, signal processing circuit and Beidou positioning module; the dual-mode MCU chip is connected to the signal processing circuit and Beidou positioning module respectively, and is used to control the dual-mode switching and data transmission of power line carrier communication and wireless radio frequency communication, and process the positioning information uploaded by the Beidou positioning module; the signal processing module is used to amplify the power line carrier signal and the radio frequency signal, filter the receiver, match the filter and switch the transmit and receive; the Beidou positioning module is used to receive Beidou satellite positioning information and send the positioning information to the dual-mode MCU chip.

2. The dual-mode communication operation and maintenance system based on BeiDou positioning according to claim 1, characterized in that, The strong and weak current interface module includes a weak current interface and a strong current interface; the weak current interface is used to connect and communicate with the electricity meter and obtain the operating power of the electricity meter; the strong current interface is used to couple carrier signals to the power line.

3. The dual-mode communication operation and maintenance system based on BeiDou positioning according to claim 2, characterized in that, Each signal line of the low-voltage interface includes an RC protection circuit; each RC protection circuit includes a series resistor and a parallel capacitor.

4. The dual-mode communication operation and maintenance system based on BeiDou positioning according to claim 1, characterized in that, The power management module includes a DC-DC circuit and an LDO circuit. The DC-DC circuit is used to step down the input voltage provided by the meter to obtain a converted voltage value. The LDO circuit is connected to the output of the DC-DC circuit and is used to regulate the converted voltage value to obtain a stable voltage. The stable voltage is then provided to the dual-mode MCU chip, the signal processing circuit, and the Beidou positioning module.

5. The dual-mode communication operation and maintenance system based on BeiDou positioning according to claim 2, characterized in that, The signal processing module includes an HPLC signal processing circuit and an HRF signal processing circuit. The HPLC signal processing circuit is connected between the dual-mode MCU chip and the high-voltage interface, and is used to amplify and filter the original carrier signal emitted by the dual-mode MCU chip. The HRF signal processing circuit is connected between the dual-mode MCU chip and the antenna, and is used to perform matched filtering and transmit / receive switching on the radio frequency signal emitted by the dual-mode MCU chip.

6. The dual-mode communication operation and maintenance system based on BeiDou positioning according to claim 5, characterized in that, The HPLC signal processing circuit includes a carrier transmission amplification circuit and a carrier signal coupling and receiving filtering circuit. The carrier transmission amplification circuit includes a carrier power amplification chip for amplifying the carrier signal output by the dual-mode MCU chip. The carrier signal coupling and receiving filtering circuit includes a coupling transformer, a filtering network, and a clamping protection circuit for coupling the amplified carrier signal to the power line and filtering out out-of-band noise from the carrier signal received from the power line.

7. The dual-mode communication operation and maintenance system based on BeiDou positioning according to claim 5, characterized in that, The HRF signal processing circuit includes an RF switch, a matching inductor, and a filter capacitor; the matching inductor and the filter capacitor form an RF matching network, which is used for impedance matching and out-of-band noise suppression of the RF signal; the RF switch is used to control the switching of the RF signal's transmit and receive paths.

8. The dual-mode communication operation and maintenance system based on BeiDou positioning according to claim 1, characterized in that, The dual-mode MCU chip is a dual-mode communication chip that supports broadband power line carrier and Sub-GHz wireless transceiver functions.

9. The dual-mode communication operation and maintenance system based on BeiDou positioning according to claim 1, characterized in that, The Beidou positioning module includes a power decoupling capacitor, a serial port signal RC filter, and an electrostatic discharge protection tube.

10. The dual-mode communication operation and maintenance system based on BeiDou positioning according to claim 1, characterized in that, It also includes an early warning unit, which is used to detect the meter displacement threshold through the dual-mode MCU module and report the position offset data through the signal processing module.

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