Remote switch system of cable branch box

Abstract

The utility model discloses a remote switch system for a cable branch box, and relates to the technical field of power equipment. The problems that an existing system is insufficient in anti-interference capacity, unstable in wireless signal and high in power supply dependence are solved. In the scheme, the control module integrates the dual-core processor and the nonvolatile storage unit, and high-frequency noise conduction is blocked through a four-stage isolation driving circuit; the communication module is fused with a power line carrier and a dual-frequency wireless transceiver circuit to realize signal blind area automatic switching and multi-channel complementary transmission; the multi-source power supply module adopts a main power supply, a standby power supply and a photovoltaic unit to cooperatively supply power, and combines a bidirectional DC / DC module to dynamically deploy energy; the split type execution module doubly guarantees the reliability of the switch based on a magnetic latching relay and a redundant drive circuit; according to the scheme, the anti-interference capability in a complex electromagnetic environment is remarkably improved, control failure caused by signal disconnection is effectively avoided, and the continuous operation capability in a power-off scene is ensured through a multi-source energy supply mechanism.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of electric power equipment, and more exactly relates to a cable branch box remote switch system. BACKGROUND

[0002] In modern electrical distribution systems, the demand for cable branch box remote switch systems stems from the pursuit of safety, efficiency, and manageability in industrial and utility environments. Traditionally, operating switches and controls for cable branch boxes required personnel to be on-site, often in dangerous or hard-to-reach areas. The advent of remote switch systems has addressed these challenges, allowing operators to manage electrical distribution from a safe distance. This development is part of the trend towards electrical engineering automation and digitization, benefiting from advances in communication technology and the demand for more reliable, maintenance-friendly systems.

[0003] Cable branch box remote switch systems primarily employ wired and wireless technologies. Wired systems use control cables for signal transmission, making them suitable for scenarios requiring high reliability; wireless systems use radio frequency (RF) communication, offering flexibility in installation and suitability for highly mobile environments. Both are integrated with SCADA systems, providing centralized management and real-time monitoring, and include safety features such as emergency stops and status feedback, in line with relevant electrical standards. However, while existing cable branch box remote switch systems offer convenience in terms of functionality, they have some drawbacks in actual implementation and use: First, current remote switch systems primarily rely on electronic relays and wireless signals for control. However, in strong electromagnetic environments such as high-voltage substations and factories, wireless signals are susceptible to harmonic interference and high-frequency noise, leading to abnormal control commands or signal loss. Although existing systems use shielding and filtering techniques, they may still trigger false actions or system restarts in response to high-frequency electromagnetic pulses such as lightning strikes or short-circuit transient impacts. Additionally, existing cable branch box remote switch systems rely on wireless communication technologies such as 4G / 5G and LoRa. However, in environments with weak signal coverage such as underground, tunnels, and mountainous areas, wireless data transmission may experience delays, packet loss, or disconnections, leading to switch operation failure or excessively long response times. Furthermore, in high-concurrency environments, existing systems lack local computing capabilities and rely entirely on cloud control, causing system performance to decline when the network is congested. Second, wired systems require continuous power supply, while wireless systems rely on batteries with limited lifespan. In the event of power grid failure, equipment maintenance, or unexpected power outages, the system may lose remote control capabilities if there is no reliable backup power source (302). Although some systems use lithium batteries or ultra-low power consumption technology, the battery life is limited, and the system still faces energy shortages in the event of prolonged power outages; therefore, there is a need to disclose a cable branch box remote switch system. SUMMARY

[0004] The purpose of this invention is to design a remote switch system for cable branch boxes to address the shortcomings mentioned in the background art.

[0005] To achieve the above-mentioned technical effects, the present invention adopts the following technical solution:

[0006] A remote switching system for a cable branch box includes: a control module comprising a dual-core processor, a non-volatile memory unit, and a four-level isolation drive circuit;

[0007] The communication module includes a power line carrier circuit, a dual-frequency wireless transceiver circuit, and a hardware switching circuit.

[0008] The multi-source power supply module includes a main power supply, a backup power supply, a photovoltaic supplement unit, and a bidirectional DC / DC module;

[0009] The separate execution module includes a magnetic latching relay and redundant drive circuitry.

[0010] The input terminal of the control module is connected to an external control signal, and the output terminal is connected in sequence to the communication module and the split execution module; the multi-source power supply module provides independent power to each module.

[0011] Furthermore, the communication module, control module, and multi-source power supply module are each housed in an independent metal shielded enclosure. Power filtering is achieved between the enclosures via feedthrough capacitors, and high-frequency signals are transmitted via SMA connectors. The inner wall of the communication module enclosure is covered with a copper mesh shielding layer, and aluminum alloy heat dissipation fins are welded to the outside. The control module enclosure uses an aluminum-magnesium alloy shell, and the interior is filled with conductive foam to isolate high-frequency interference. The inner wall of the multi-source power supply module is coated with an iron-silicon-aluminum magnetic powder coating.

[0012] Furthermore, the dual-core processor includes an ARM main control chip, a RISC-V coprocessor, and a transient suppression protection circuit; the ARM main control chip and the RISC-V coprocessor are connected via a magnetically isolated bus; the transient suppression protection circuit includes a TVS diode array and a common-mode choke, and the transient suppression protection circuit is connected in series on the power supply pins of the ARM main control chip and the RISC-V coprocessor.

[0013] Furthermore, the four-stage isolation drive circuit includes an optocoupler isolation unit, a capacitor isolation unit, a pulse transformer, and a gas discharge tube connected in sequence; the input terminal of the optocoupler isolation unit is connected in series with a current-limiting resistor; the capacitor isolation unit is composed of a Y capacitor and a common-mode choke connected in parallel; a Zener diode is connected in parallel on the primary side of the pulse transformer, and the secondary side is connected to the drive signal output terminal; the gas discharge tube is connected across the output terminal and the ground copper plate.

[0014] Furthermore, the power line carrier circuit includes a coupling transformer and a noise cancellation sub-circuit; the primary side of the coupling transformer is connected in series with an LC matching network, and the secondary side is connected to a differential amplifier; the noise cancellation sub-circuit consists of an analog multiplier and an operational amplifier forming a closed-loop feedback, the feedback signal is taken from the secondary side of the coupling transformer, and the output is connected to the switching circuit via a π-type filter.

[0015] Furthermore, the dual-frequency chip TI CC1352R of the dual-frequency wireless transceiver circuit is connected to the waveguide antenna, which is composed of a rectangular waveguide with a cutoff frequency of 3GHz and an embedded ferrite absorbing layer.

[0016] Furthermore, the hardware switching circuit includes an electromagnetic field strength probe and a switching execution unit; the electromagnetic field strength probe is used to detect the field strength in the 10kHz-3GHz frequency band, and its output is connected to a voltage comparator; the switching execution unit includes a parallel RF relay and a light-controlled MOS transistor, the RF relay is connected to the output of the voltage comparator through a Schmitt trigger, and the gate of the light-controlled MOS transistor is controlled by optocoupler isolation.

[0017] Furthermore, the main power supply uses an AC / DC conversion circuit to connect to the mains power, with an EMI filter RN112 connected in series at the front end; the backup power supply consists of a lithium iron phosphate battery pack and a supercapacitor pack connected in parallel; the photovoltaic supplement unit consists of a monocrystalline silicon solar panel connected to the backup power supply through an MPPT controller; the bidirectional DC / DC module is used for charging and discharging switching between the main power supply and the backup power supply.

[0018] Furthermore, the supercapacitor bank consists of six 2.7V / 500F capacitors connected in series to form a 16.2V module, with each capacitor connected in parallel to an equalizing resistor. The three modules are connected in parallel via diodes and then connected to the energy storage bus. A MOSFET switch is connected in series in the discharge circuit of the supercapacitor bank, and the current is controlled by a voltage monitoring chip LTC6804. An anti-reverse current diode is connected in series between the output of the MPPT controller and the lithium iron phosphate battery pack.

[0019] Furthermore, the redundant drive circuit is driven by two independent optocoupler isolation channels connected in parallel to drive the same relay coil; the two optocoupler input signals of the redundant drive circuit are checked for consistency through an XOR gate.

[0020] In summary, due to the adoption of the above technical solution, the beneficial effects of this utility model are:

[0021] First, through hardware redundancy design of power line carrier and dual-band wireless communication, the communication medium is automatically switched in strong electromagnetic environments to avoid command loss or malfunctions caused by high-frequency noise and harmonic interference. Simultaneously, a four-level isolation drive circuit blocks transient voltage surges, ensuring stable system operation under lightning strikes or short-circuit impacts. Second, power line carrier communication provides a stable transmission channel in wireless signal dead zones such as underground locations and tunnels, while dual-band wireless communication achieves rapid response in conventional scenarios. The two complement each other through a hardware switching mechanism, completely resolving control failures caused by signal disconnection. Furthermore, the dual-core processor and non-volatile memory unit form a local computing core, enabling independent operation in high-concurrency scenarios. The system completes logical judgment and command execution, eliminating complete reliance on cloud control and avoiding response delays caused by network congestion. The multi-source power supply module, through intelligent coordination of the main power supply, backup power supply, and photovoltaic supplementary unit, prioritizes the photovoltaic unit to maintain basic power supply in the event of grid failure or unexpected power outage. At the same time, the backup power supply dynamically supplements the gap through a bidirectional DC / DC module, completely solving the risk of remote control interruption caused by insufficient battery life in traditional systems. The split execution module reduces the impact of electromagnetic interference on the magnetic latching relay through physical isolation layout. The redundant drive circuit automatically activates the backup channel in the event of a single-channel failure, preventing switch malfunction due to interference or component damage. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model 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 this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0023] Figure 1 This is a diagram of the overall working architecture of this utility model;

[0024] Figure 2 This is a schematic diagram of the architecture of the communication module of this utility model;

[0025] Figure 3 This is a schematic diagram of the architecture of the multi-source power supply module of this utility model;

[0026] The diagram is labeled as follows: 100, Control Module; 200, Communication Module; 300, Multi-Source Power Supply Module; 400, Split-Type Execution Module; 201, Power Line Carrier Circuit; 202, Dual-Frequency Wireless Transceiver Circuit; 203, Hardware Switching Circuit; 301, Main Power Supply; 302, Backup Power Supply; 303, Photovoltaic Supplement Unit; 304, Bidirectional DC / DC Module. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0028] To make the above-mentioned objects, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.

[0029] It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediary element present. Conversely, when an element is said to be "directly" connected to another element, there is no intermediary element. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0030] In this solution, a remote switch system for a cable branch box includes:

[0031] The control module 100 includes a dual-core processor, a non-volatile memory unit, and a four-level isolation drive circuit;

[0032] The communication module 200 includes a power line carrier circuit 201, a dual-frequency wireless transceiver circuit 202, and a hardware switching circuit 203.

[0033] The multi-source power supply module 300 includes a main power supply 301, a backup power supply 302, a photovoltaic supplement unit 303, and a bidirectional DC / DC module 304;

[0034] The split execution module 400 includes a magnetic latching relay and redundant drive circuitry.

[0035] In such Figure 1As shown, the system's operational connections are as follows: the input terminal of the control module 100 is connected to an external control signal, and the output terminal is sequentially connected to the communication module 200 and the split-type execution module 400; the multi-source power supply module 300 provides independent power to each module. The communication module 200, control module 100, and multi-source power supply module 300 are each housed in an independent metal shielded enclosure. Power filtering is achieved between the enclosures via a feedthrough capacitor, and high-frequency signals are transmitted via an SMA connector. The inner wall of the communication module 200 enclosure is covered with a copper mesh shielding layer, and aluminum alloy heat dissipation fins are welded to the outside. The control module 100 enclosure uses an aluminum-magnesium alloy shell, with conductive foam filling the interior to isolate high-frequency interference. The inner wall of the multi-source power supply module 300 is coated with an iron-silicon-aluminum magnetic powder coating.

[0036] In one embodiment of this system applied in a high-voltage substation, the specific workflow is as follows:

[0037] First, remote control commands are transmitted to the communication module 200 via dual-band wireless 915MHz / 2.4GHz or power line carrier. When the electromagnetic field probe detects that the environmental interference intensity exceeds the threshold, such as >50V / m, the hardware switching circuit 203 automatically switches to power line carrier communication within <5ms and transmits the signal to the control module 100 through the coupling transformer T1.

[0038] After receiving instructions, the dual-core processor ARM Cortex-M7+RISC-V of the control module 100 performs local decision-making by combining the preset logic in the non-volatile memory unit MRAM+EEPROM, with a response time of <50ms. The four-level isolation drive circuit 204 outputs the processed PWM signal to the execution module after four-level isolation through optocoupler 6N137, capacitive isolation Y capacitor + common mode choke, pulse transformer T2 and gas discharge tube G1.

[0039] When the mains power is normal, the main power supply 301 provides power and charges the battery / capacitor with a constant current of 1A; after the mains power is interrupted, the supercapacitor provides a peak current of 20A within 5ms of instantaneous discharge, and the photovoltaic system prioritizes power supply for illumination ≥200W / m². 2 Output ≥15W; the battery only starts when the capacitor voltage is <10V, and the battery life is ≥72 hours.

[0040] The magnetic latching relay of the split execution module 400 operates after receiving the drive signal. If the main drive circuit fails, the redundant drive circuit is automatically activated, with a switching time of <10ms.

[0041] In this embodiment, the dual-band wireless chip TI CC1352R and the power line carrier circuit 201 are placed on opposite sides of the shielded enclosure, while the waveguide antenna ANT1 is exposed on the top of the enclosure. A copper-nickel alloy cavity with a thickness of 1.5mm is used to isolate interference. The dual-core processor and the isolated drive circuit are arranged in layers, with the magnetic isolation bus ADuM5402 spaced less than 3cm away from the processor to reduce signal attenuation. The multi-source power supply module 300, the main power supply 301 (220V to 12V / 10A), and the bidirectional DC / DC module 304LT8705 are installed at the bottom of the enclosure. The 12.8V / 40Ah lithium iron phosphate battery and the 16.2V / 100F supercapacitor are placed in a waterproof enclosure. The 18V / 200W photovoltaic panel is led to the top of the enclosure through flange holes, and the bidirectional DC / DC module 304 (efficiency >95%) is mounted on an aluminum heat sink substrate. The 250A magnetic latching relay contacts are independently packaged in a steel enclosure with heat sink fins, with a distance >10cm between them and the drive circuit to reduce electromagnetic coupling.

[0042] In practice, this system, through hardware redundancy design, multi-source power supply architecture and physical isolation layout, achieved a 99.99% communication success rate and 48-hour power outage recovery in actual tests at high-voltage substations, which is significantly better than traditional solutions.

[0043] In the above embodiments, the dual-core processor includes an ARM main control chip, a RISC-V coprocessor, and a transient suppression protection circuit; the ARM main control chip and the RISC-V coprocessor are connected via a magnetically isolated bus; the transient suppression protection circuit includes a TVS diode array and a common-mode choke, and is connected in series on the power supply pins of the ARM main control chip and the RISC-V coprocessor. The four-stage isolation drive circuit includes an optocoupler isolation unit, a capacitor isolation unit, a pulse transformer, and a gas discharge tube connected in sequence; a current-limiting resistor is connected in series at the input terminal of the optocoupler isolation unit; the capacitor isolation unit is composed of a Y capacitor and a common-mode choke connected in parallel; a Zener diode is connected in parallel on the primary side of the pulse transformer, and the secondary side is connected to the drive signal output terminal; the gas discharge tube is connected across the output terminal and the ground copper plate.

[0044] In practical implementation, the ARM main control chip STM32H743VIT6 and the RISC-V coprocessor GD32VF103VBT6 achieve cross-power domain data interaction through the ADUM1201AR magnetically isolated bus. The ARM chip is responsible for running the FreeRTOS real-time operating system, parsing remote instructions and scheduling tasks, and its GPIO pins PA0-PA15 are connected to the external communication interface; the RISC-V coprocessor is dedicated to signal preprocessing and anomaly detection, and reads and writes data to the non-volatile memory unit W25Q256JVSIQ through the SPI interface SCK / MISO / MOSI pins. The transient suppression protection circuit integrates a TVS diode array SMAJ5.0A and a common-mode choke DLW21SN121SQ2L. The TVS diodes are connected in parallel to the 3.3V power supply pin of the dual-core processor, with a clamping voltage ≤6.4V. The common-mode choke is connected in series at the power input terminal. Combined with a π-type filter network, a 10μF electrolytic capacitor C1 and a 0.1μF ceramic capacitor C2, high-frequency noise is suppressed. The four-stage isolation drive circuit consists of an optocoupler isolation unit TLP291-4, a 2.2nF Y capacitor and a 15mH common-mode choke connected in parallel, a pulse transformer PE-65612NL, and a gas discharge tube 3R090 connected in series. The optocoupler input receives the PWM signal PC6 pin of the ARM chip through a 1kΩ current-limiting resistor. The output drives the pulse transformer after the differential-mode interference is filtered out by the Y capacitor. The secondary side outputs a 12V pulse signal to the drive terminal J1. The gas discharge tube is connected between the output and a 2mm thick grounding copper plate to discharge lightning overvoltage.

[0045] During operation, remote commands are transmitted to the ARM main control chip via the RS485 bus MAX3485ESA chip, and stored in the W25Q256 non-volatile memory after CRC verification. The RISC-V coprocessor scans the memory area in real time, triggers an interrupt upon detecting a new command, and sends an execution request to the ARM via the magnetically isolated ADUM1201AR bus. The ARM parses the command and generates a 1kHz PWM waveform, which is converted into a 12V pulse signal to drive an external relay through a four-stage isolation drive circuit. When the power supply experiences ±200mV / μs transient noise, the TVS diode array quickly clamps the voltage, the common-mode choke suppresses interference above 10MHz, and the four-stage isolation drive blocks interference paths step by step: optocouplers eliminate common-mode noise, Y capacitors filter differential-mode interference, pulse transformers enhance drive capability, and gas discharge tubes discharge residual overvoltage. The RISC-V coprocessor continuously monitors the drive feedback signal PC8 pin. If a pulse loss or abnormal duty cycle is detected, it immediately notifies the ARM to start redundant instructions via the magnetic isolation bus. The non-volatile memory stores the most recent 100 operation logs, and the data can be retained for more than 10 years after power failure.

[0046] During hardware installation, the 180mm×120mm control module PCB board is fixed to the inner wall of the cable distribution box using M4 nylon screws, 300mm from the bottom of the box, with a 2mm thick PTFE insulating sheet between it and the metal enclosure. The dual-core processor and isolation drive circuit are centrally located on the left side of the PCB, the transient suppression circuit is near the power input, and the four-stage drive unit is near the output terminals. A 100mm×80mm×2mm grounding copper plate is soldered to the enclosure 16mm from the bottom. 2 The grounding busbar and power input line are both AWG18 twisted-pair shielded cables with single-end grounding. The drive output terminals are connected to the relay coil via silicone high-voltage wire with a withstand voltage of 1kV. The PCB surface is coated with 0.1mm conformal coating, and a 0.5mm aluminum shield is added to the optocoupler and pulse transformer areas. A 10mm isolation gap is reserved around the gas discharge tube. This design reduces the signal bit error rate to 0% under a 10kV / 1.2μs surge, achieves a dual-core collaborative processing instruction delay of <10μs, suppresses power supply noise to below 50mVpp, and allows for replacement within 15 minutes during installation and maintenance. It significantly improves the system's anti-interference capability, response speed, and maintenance efficiency, providing a reliable solution for cable branch box control in complex electromagnetic environments.

[0047] In the above embodiments, the power line carrier circuit 201 includes a coupling transformer and a noise cancellation sub-circuit; the primary side of the coupling transformer is connected in series with an LC matching network, and the secondary side is connected to a differential amplifier; the noise cancellation sub-circuit consists of an analog multiplier and an operational amplifier forming a closed-loop feedback, the feedback signal is taken from the secondary side of the coupling transformer, and the output is connected to the switching circuit via a π-type filter. The dual-frequency wireless transceiver circuit 202's dual-frequency chip TI CC1352R RF output is connected to a waveguide antenna, which is composed of a rectangular waveguide with a cutoff frequency of 3GHz and an embedded ferrite absorbing layer. The hardware switching circuit 203 includes an electromagnetic field strength probe and a switching execution unit; the electromagnetic field strength probe is used to detect the field strength in the 10kHz-3GHz frequency band, and its output is connected to a voltage comparator; the switching execution unit includes a parallel RF relay and a photoelectric MOS transistor, the RF relay is connected to the output of the voltage comparator via a Schmitt trigger, and the gate of the photoelectric MOS transistor is controlled by optocoupler isolation.

[0048] In practical implementation, the coupling transformer uses an EPCOS B82721J2102N1 high-frequency transformer with a 1MHz bandwidth and a primary inductance of 10mH. Its primary side is connected in series with an LC matching network L1 = 10μH, C1 = 220nF, and C2 = 470pF, directly connected to the 10kV main line voltage level of the cable branch box. The secondary side is connected to a differential amplifier AD8137, with pins 3 and 4 as inputs and pin 6 as the output, amplifying the carrier signal. The noise cancellation sub-circuit receives the secondary signal from pins X1 and Y1 of the analog multiplier AD835, and outputs the product signal from pin Z. This product signal is then fed back to the operational amplifier OPA2134, with pin 2 connected to a feedback resistor R1 = 10kΩ, and pin 6 outputting the canceled signal, forming a closed-loop feedback to eliminate common-mode noise on the cable in real time. The π-type filter consists of an L2 = 15μH inductor and capacitors C3 = 100nF and C4 = 100nF, filtering out high-frequency harmonics before outputting to the switching circuit. The dual-band chip TI CC1352R supports both 915MHz and 2.4GHz frequency bands. Its RF output pin RF_P is connected via a microstrip line to the TX port of the circulator (model SKYFR-000789), operating in the 0.7-3GHz frequency band. The receiver RF_N is connected to the RX port of the circulator. The waveguide antenna consists of a rectangular waveguide measuring 30mm × 15mm × 100mm, with a cutoff frequency of 3GHz and an embedded ferrite absorbing layer of 2mm thickness (model TDK HF50). The antenna interface is connected to the circulator's ANT port via an SMA connector (model R125.072.000). The split-type shielded cavity is made of a 1.5mm thick copper-nickel alloy and filled with conductive foam (Laird Technologies ECCOSTOCK HIK). The wireless circuit board is fixed to the bottom of the cavity with nylon screws. Electromagnetic field strength probe: A Langer EMV-Technik RF-R 3-3 probe with a frequency range of 10kHz-3GHz and a sensitivity of 1mV / (V / m) is used. Its output BNC interface connects to a voltage comparator TLV3501, pin 3 of which is the threshold setting terminal, with a setting voltage of 2.5V. RF relay G6K-2F with a switching time of 3ms. The coil is driven by the comparator output via a Schmitt trigger SN74LVC1G17 pin 2. Optically controlled MOSFET TLP190B with an on-resistance of 0.5Ω has its gate controlled by an optocoupler TLP521-4 pin 4, with its drain and source connected in parallel to the relay contacts.

[0049] During implementation, under normal conditions, the dual-frequency chip CC1352R receives remote commands via the 915MHz band. The signal is isolated by a circulator and radiated by a waveguide antenna. When a higher quality signal is detected in the 2.4GHz band, the chip automatically switches to high-speed mode. When the electromagnetic field probe detects an environmental interference intensity >50V / m, the voltage comparator TLV3501 outputs a high level, triggering the Schmitt trigger SN74LVC1G17, which switches the RF relay G6K-2F to the carrier path. Simultaneously, the optically controlled MOSFET TLP190B is turned on, forming dual-path redundancy. The power line carrier signal is coupled to the secondary side via the coupling transformer B82721J2102N1. The AD8137 differential amplifier amplifies the signal by 20dB before sending it to the noise cancellation loop. The AD835 multiplier multiplies the secondary-side noise sample with the original signal, and the result is inverted and superimposed by the OPA2134 operational amplifier to cancel common-mode interference. The processed signal is filtered by a π-type filter (L2+C3+C4) to remove high-frequency noise before being output to the control module 100. An electromagnetic field probe monitors the field strength in the 10kHz-3GHz frequency band in real time. When the detected value exceeds the threshold, the hardware switching circuit 203 completes path switching within <5ms. An RF relay handles the main path switching, while a photoelectric MOSFET provides a backup channel to ensure uninterrupted communication under extreme interference.

[0050] In this embodiment, the communication module 200 is installed within a 300mm × 200mm × 100mm cavity on the side wall of the cable branch box. The waveguide antenna is exposed on the top of the box, more than 50cm away from the high-voltage cable connector to avoid metal obstruction affecting radiation efficiency. The coupling transformer is fixed to a 2mm thick epoxy resin insulating board with M4 bolts. The primary side terminal block WAGO 221-613 is directly connected to the main cable line, and the secondary side leads use twisted-pair shielded cable Belden 8723 connected to the AD8137 amplifier. The π-type filter is positioned close to the switching circuit. Inductor L2 and capacitors C3 and C4 are surface-mounted with pad spacing greater than 5mm to reduce the impact of distributed capacitance. The dual-band chip CC1352R and the circulator SKYFR-000789 are housed together in a copper-nickel alloy shielded cavity. The cavity is bonded to the side wall of the enclosure with conductive adhesive 3M 9703. The waveguide antenna is exposed on the top of the enclosure via an SMA connector. The circuit board inside the shielded cavity is fixed with nylon screws, with a 3mm gap between the board and the cavity to avoid short-circuit risks. The electromagnetic field probe RF-R3-3 is vertically mounted at the opening on the side wall of the enclosure, with the probe tip extending 5cm out of the enclosure and facing the direction of the high-voltage cable. The RF relay G6K-2F and the optically controlled MOSFET TLP190B are soldered side by side to an independent daughterboard, which is connected to the main control board via a pin header socket for easy maintenance and replacement. The inner wall of the communication module 200 is covered with copper foil tape 3M 1181, and the seams are sealed with beryllium copper springs Chomerics CHO-SEAL 6504; all external cables passing through the compartment are equipped with Murata NFM18PC105B1H3, 1μF / 50V, and fitted with ferrite magnetic rings TDKMMZ1608D102BTA00.

[0051] Furthermore, the main power supply 301 uses an AC / DC conversion circuit to connect to the mains power, with an EMI filter RN112 connected in series at the front end; the backup power supply 302 consists of a lithium iron phosphate battery pack and a supercapacitor pack connected in parallel; the photovoltaic supplement unit 303 consists of a monocrystalline silicon solar panel connected to the backup power supply 302 via an MPPT controller; the bidirectional DC / DC module 304 is used for charging and discharging switching between the main power supply 301 and the backup power supply 302. The supercapacitor pack consists of six 2.7V / 500F capacitors connected in series to form a 16.2V module, and each capacitor is connected in parallel with a voltage equalization resistor. The three modules are connected in parallel via diodes and then connected to the energy storage bus; a MOSFET switch is connected in series in the discharge circuit of the supercapacitor pack, and the current is controlled by a voltage monitoring chip LTC6804; an anti-reverse current diode is connected in series between the output of the MPPT controller and the lithium iron phosphate battery pack.

[0052] In practical implementation, the main power supply 301 uses a UCC28070 interleaved PFC controller with pin VCC=12V and GND grounded. A front-end series EMI filter RN112 with a rated current of 10A and insertion loss of 60dB@10MHz suppresses high-frequency noise from the mains input. The AC / DC conversion circuit uses an IRFP460 MOSFET with a withstand voltage of 500V and an STTH8R06D fast recovery diode to convert 220V AC to 12V / 10A DC output. The backup power supply 302 includes a 12.8V / 40Ah lithium iron phosphate battery pack, a BYD LF12.8-40 battery, and six Maxwell 2.7V / 500F supercapacitors connected in series to form a 16.2V module. Each capacitor is connected in parallel with a 10kΩ / 2W voltage-equalizing resistor with 1% accuracy. The three modules are connected in parallel to the energy storage bus via a 100V MBR20100CT anti-reverse-feedback diode. In the supercapacitor discharge circuit, an IRF4905 MOSFET switch is connected in series, with its gate connected to the GPIO pin of an LTC6804-2 voltage monitoring chip. The LTC6804-2 pins C0-C5 monitor the voltage of each individual capacitor to control its on / off state and prevent over-discharge. The photovoltaic supplement unit 303 uses an EPever Tracer3210AN MPPT controller with an input voltage of 10-50V and an efficiency of 99%. Its output is connected to the positive terminal of the lithium iron phosphate battery pack via an MBR2045CT anti-reverse-feedback diode with a forward voltage drop of 0.3V. The solar panel is 24V / 200W, and the monocrystalline silicon is connected to the MPPT input terminal via a waterproof connector PG9.

[0053] The main power supply 301 outputs 24V, which is connected to the positive terminal (BUS+) of the supercapacitor bank via the VIN pin of the bidirectional DC / DC module 304LM5170, while the negative terminal (BUS-) is grounded. The positive terminal of the lithium iron phosphate battery pack is connected to BUS+ via the PACK+ pin of the BQ76940, and the PACK- is directly grounded. The V+ pin of the LTC6804 is connected to the overall positive terminal of the supercapacitor bank, the V- pin is grounded, and the S pin communicates with the main control module via the ISO7640FM isolation chip. The positive terminal of the solar panel is connected to the PVIN pin of the BQ24650, and the negative terminal is grounded. The BAT pin of the BQ24650 is connected to BAT via the anode of the MBR20100CT diode, and the cathode is connected to BUS+ to charge the backup power supply 302. The GPIO1 pin of the LTC6804 is connected to the IN pin of the LTC4440. When the supercapacitor voltage is detected to be greater than 14V, the LTC4440 outputs a 12V drive signal to the gate of the IRFP4668PbF to turn on the discharge circuit. The MOSFET source current sampling resistor is 0.01Ω / 5W, which is fed back to the VREF pin of the LTC6804 to realize overcurrent protection.

[0054] The 220V AC mains input, after being filtered by the RN112 EMI filter to remove high-frequency interference, enters the PFC circuit controlled by the UCC28070. The output 12V DC is split into two paths: one directly powers the system, and the other charges the backup power supply 302 via the bidirectional DC / DC module 304LTC3789 (pins VIN=12V, VOUT=14.4V). Each of the three supercapacitor modules (16.2V / 83.3F) is connected in parallel via an MBR20100CT diode. The 16.2V energy storage bus and the 12.8V lithium iron phosphate battery pack are dynamically adjusted for charging and discharging via the LTC3789: when the mains power is normal, the LTC3789 boosts the 12V to 14.4V to charge the battery and capacitor; when the mains power is interrupted, the LTC3789 switches to buck mode, reducing the 16.2V from the supercapacitor to the 12V output. The LTC6804-2 chip's SPI interface pins SCK / MISO / MOSI connect to the main control unit, reporting capacitor voltage accuracy of ±0.25% in real time. If a single cell voltage is detected to be >2.75V or <2.2V, the IRF4905 MOSFET protection capacitor is immediately turned off. After the photovoltaic panel output is tracked for maximum power point by the MPPT controller, it is unidirectionally injected into the backup power supply 302 bus via the MBR2045CT diode to prevent reverse discharge of the battery at night.

[0055] Under normal mains power conditions, the main power supply 301 prioritizes power supply to the system and charges the supercapacitors and lithium iron phosphate batteries in constant current 5A mode via the LTC3789. At this time, the LTC6804-2 chip continuously monitors the voltage of each individual cell in the supercapacitor bank. If the voltage difference exceeds 50mV, its internal balancing circuit automatically balances the charge through a 100Ω resistor to ensure the lifespan of the capacitor bank. The photovoltaic panel operates at ≥200W / m² under sufficient sunlight. 2 The MPPT controller replenishes energy, with a maximum output power of 180W, prioritizing the charging of the supercapacitor to meet instantaneous high current demands. When mains power is interrupted or voltage fluctuations exceed ±20%, the bidirectional DC / DC module 304 immediately switches to backup power mode: the supercapacitor releases stored energy through the IRF4905 MOSFET, providing a peak current of 100A within 5ms to meet the instantaneous high power consumption demands of relay drives, etc. Simultaneously, the LTC3789 steps down the supercapacitor's 16.2V to 12V to continuously power the system. If the supercapacitor voltage drops to 2.0V per cell (12V), the LTC6804-2 automatically switches to lithium iron phosphate battery power to prevent over-discharge. During this process, the MPPT controller continues to collect solar energy to replenish the battery; in cases of insufficient sunlight, the battery can independently maintain system operation for ≥72 hours.

[0056] The multi-source power supply module 300 is installed in an independent compartment at the bottom of the cable branch box, measuring 400mm × 300mm × 200mm, with an IP67 protection rating. The specific layout is as follows: Main power supply 301 and bidirectional DC / DC module 304: The UCC28070 controller and IRFP460 MOSFET are fixed to a 5mm thick heat-dissipating aluminum substrate and mounted on the left side of the compartment using M4 screws. The AC input line is an AWG14 three-core shielded cable threaded through a Φ25mm metal flexible conduit and fitted with a RH3.5-16-10 magnetic ring to suppress conducted interference. Three parallel supercapacitor modules and a lithium iron phosphate battery pack are housed in a waterproof compartment. The supercapacitor modules are connected via copper busbars with a cross-sectional area of ​​25mm². 2 The battery packs are connected in parallel to the LTC3789 output via silicone wires that are temperature resistant from -40℃ to 150℃. The LTC6804-2 monitoring board is mounted flush against the capacitor bank and connected to each cell's voltage detection point via FFC cables with 0.5mm spacing. The EPever Tracer3210AN MPPT controller is fixed to a bracket on the top of the chamber. Its input terminals are connected to the roof solar panel at a 30° angle via IP68 waterproof connectors. The bracket is made of 6063 aluminum alloy. The output AWG12 twisted-pair cable is routed into the chamber via a cable tray and crimped to an MBR2045CT diode. The main power supply 301 heatsink is exposed on the side wall of the chamber, using a DC12V, 0.2A forced air cooling system with an axial fan. The supercapacitor bank is covered with a flame-retardant silicone sleeve, and the chamber is filled with nitrogen to reduce oxidation risk. All terminals are coated with MG832 conductive paste to prevent corrosion.

[0057] Furthermore, the redundant drive circuit is driven by two independent optocoupler isolation channels connected in parallel to drive the same relay coil; the two optocoupler input signals of the redundant drive circuit are checked for consistency through an XOR gate.

[0058] In practical implementation, the magnetic latching relay uses the TE Connectivity EV200AAANA with a contact capacity of 250A / 24VDC and a coil voltage of 24V. It employs a bistable magnetic latching structure, requiring only pulse drive to switch states. The instantaneous peak value of the coil drive current is 5A with a pulse width of 50ms, and no power supply is needed in steady state, reducing energy consumption.

[0059] The redundant drive circuit uses two independent optocouplers HCPL-0601 with a propagation delay of 300ns and an isolation voltage of 5kV RMS. The input pins 1-2 are connected to the GPIO1 main channel and GPIO2 spare channel of the control module 100, respectively. The output pins 5-6 are connected in parallel to drive the same MOSFET model, Infineon IRF540N, 100V / 33A.

[0060] The XOR gate verification uses the SN74LVC1G86 chip. Its input pin A1 is connected to GPIO1, input pin B2 is connected to GPIO2, and output pin Y3 is connected to the fault alarm circuit. When the two input signals are inconsistent, the XOR gate outputs a high level, triggering the alarm.

[0061] The optocoupler output of the MOSFET driver circuit is connected to the gate of the IRF540N via a gate resistor R1 = 10Ω, the source is grounded, and the drain is connected to the positive terminal of the relay coil. The negative terminal of the relay coil returns to the negative terminal of the power supply via a freewheeling diode MBR20100CT.

[0062] In implementation, the main control module's drive signal GPIO124V, which is active high, is connected to the anode of pin 1 of the first optocoupler HCPL-0601 via a current-limiting resistor R2 = 220Ω, while pin 2 is grounded. The backup channel signal GPIO2 is connected to the second optocoupler in the same way. The output pins 5 of the two optocouplers are connected in parallel and then connected to the MOSFET gate through a gate resistor R1, with pins 6 grounded together. The input pin A1 of the XOR gate verification circuit SN74LVC1G86 is connected to GPIO1 via a pull-up resistor R3 = 10kΩ, the input pin B2 is connected to GPIO2, and the output pin Y3 is connected to the alarm indicator LED and the piezoelectric buzzer via a series resistor R4 = 1kΩ, driven by 5V. In the relay coil circuit, the MOSFET drain is connected to the positive terminal of the relay coil EV200AAANA pin A1, and the coil negative terminal A2 is connected to A2 via the anode of the MBR20100CT diode, with the cathode connected to the negative power supply to form a freewheeling circuit, suppressing turn-off spikes.

[0063] During implementation, when the main control module sends a drive signal, GPIO1 and GPIO2 synchronously output a high level, the two optocouplers HCPL-0601 are turned on, driving the MOSFET IRF540N to turn on, and the relay coil receives a 24V voltage pulse with a 50ms pulse width. The contact state switches from normally open to normally closed. The XOR gate SN74LVC1G86 detects that both inputs are consistently high / low, and the output Y remains low, so the alarm circuit is not triggered. If the main channel GPIO1 fails, GPIO2 can still independently drive the backup optocoupler to ensure the MOSFET is turned on. If the XOR gate detects a difference between the two signals, such as GPIO1 being low and GPIO2 being high, it outputs a high level, lighting the alarm LED and triggering the buzzer, but the system can still complete the operation through the backup channel. When both signals are abnormal, such as simultaneous high-level conflict, the XOR gate outputs a high level to trigger the alarm, and the relay automatically locks due to abnormal drive pulses, such as excessively long pulse widths, to avoid malfunction.

[0064] In implementation, the split-type execution module 400 is independently installed on the outer wall of the cable branch box, at a distance greater than 50cm from the control module 100, and coaxially aligned with the high-voltage cable connector to reduce wire bending stress. The relay box has dimensions of 150mm × 100mm × 60mm, uses a 1.5mm thick 304 stainless steel shell, has an IP67 protection rating, and is internally filled with epoxy resin (Epotec 301) to fix the contact components.

[0065] During installation: Use M8 stainless steel bolts to fix the relay base to the bottom plate of the enclosure. The EV200AAANA contact terminal pin 1 / 2 passes through a copper busbar with a cross-sectional area of ​​25mm². 2 Connect to the cable connector; coil leads A1 / A2 are made of 14AWG silicone insulated wire with a magnetic ring TDK ZCAT2032-0930 and led out to the drive circuit board.

[0066] The redundant drive circuit board, mounted vertically on a double-layer FR4 substrate above the relay, has an optical coupler HCPL-0601 and MOSFET IRF540N spaced >15mm apart to avoid thermal coupling. The XOR gate chip SN74LVC1G86 is positioned close to the GPIO input terminals, with signal lines <3cm in length to reduce crosstalk. The MOSFET IRF540N is coated with Dow Corning TC-5625 thermal grease and mounted on an aluminum heatsink measuring 40mm × 30mm × 10mm. The interior of the enclosure is coated with Humiseal 1B73 conformal coating to prevent moisture and salt spray corrosion. The drive signal lines GPIO1 / GPIO2 use Belden 8723 twisted-pair shielded cable, with the shield grounded at one end to the enclosure's grounding copper plate. The alarm output lines (LED / buzzer) are led out through a waterproof connector PG9 to the status indicator panel on the outside of the enclosure.

[0067] While specific embodiments of this utility model have been described above, those skilled in the art should understand that these specific embodiments are merely illustrative. Those skilled in the art can omit, substitute, and modify the details of the above methods and systems in various ways without departing from the principles and essence of this utility model. For example, combining the above method steps to perform substantially the same function and achieve substantially the same result according to substantially the same method falls within the scope of this utility model. Therefore, the scope of this utility model is defined only by the appended claims.

Claims

1. A cable branch box remote switch system characterized by: The utility model relates to a kind of multi-source power supply system, including: Control module (100), including dual-core processor, nonvolatile storage unit and four-stage isolation driving circuit; Communication module (200), including power line carrier circuit (201), dual-frequency wireless transceiver circuit (202) and hardware switching circuit (203); Multi-source power supply module (300), including main power supply (301), backup power supply (302), photovoltaic supplementary unit (303) and bidirectional DC / DC module (304); Split type execution module (400), including magnetic latching relay and redundant driving circuit; The input end of the control module (100) is connected to an external control signal, and the output end is connected to the communication module (200) and the split type execution module (400) in turn;The multi-source power supply module (300) provides independent power supply for each module.

2. A cable branch box remote switch system according to claim 1, characterized in that: The communication module (200), control module (100) and multi-source power supply module (300) are respectively arranged in independent metal shielding cabins, and the cabins are electrically filtered by through-hole capacitors and transmit high-frequency signals through SMA connectors;The inner wall of the communication module (200) cabin is covered with a copper mesh shielding layer, and the outside is welded with aluminum alloy heat dissipation fins;The control module (100) cabin adopts an aluminum-magnesium alloy shell, which is filled with conductive foam to isolate high-frequency interference;The inner wall of the multi-source power supply module (300) is coated with an iron-silicon-aluminum magnetic powder coating.

3. A cable junction box remote switch system according to claim 1, wherein: The dual-core processor includes an ARM master chip, a RISC-V coprocessor and a transient suppression protection circuit;The ARM master chip is connected to the RISC-V coprocessor through a magnetic isolation bus;The transient suppression protection circuit includes a TVS diode array and a common-mode choke coil, and is connected in series to the power supply pins of the ARM master chip and the RISC-V coprocessor.

4. A cable junction box remote switch system according to claim 1, wherein: The four-stage isolation driving circuit includes an optocoupler isolation unit, a capacitor isolation unit, a pulse transformer and a gas discharge tube connected in turn;The input end of the optocoupler isolation unit is connected in series with a current-limiting resistor;The capacitor isolation unit is composed of a Y capacitor and a common-mode choke coil connected in parallel;The primary side of the pulse transformer is connected in parallel with a voltage stabilizing tube, and the secondary side is connected to a driving signal output end;The gas discharge tube is connected across the output end and a ground copper plate.

5. A cable junction box remote switch system according to claim 1, wherein: The power line carrier circuit (201) includes a coupling transformer and a noise cancellation sub-circuit;The primary side of the coupling transformer is connected in series with an LC matching network, and the secondary side is connected to a differential amplifier;The noise cancellation sub-circuit is composed of an analog multiplier and an operational amplifier in a closed-loop feedback, and the feedback signal is taken from the secondary side of the coupling transformer, and the output end is connected to a switching circuit through a π-type filter.

6. A cable junction box remote switch system according to claim 1, wherein: The dual-frequency chip TI CC1352R radio frequency output end of the dual-frequency wireless transceiver circuit (202) is connected to a waveguide antenna, which is composed of a rectangular waveguide tube with a cutoff frequency of 3 GHz and an embedded ferrite wave-absorbing layer.

7. A cable junction box remote switch system according to claim 1, wherein: The hardware switching circuit (203) comprises an electromagnetic field intensity probe and a switching execution unit; the electromagnetic field intensity probe is used for detecting field intensity in a frequency band of 10 kHz-3 GHz, and an output end is connected to a voltage comparator; the switching execution unit comprises a radio frequency relay and a light-controlled MOS tube in parallel, the radio frequency relay is connected to the output end of the voltage comparator through a Schmitt trigger, and a gate of the light-controlled MOS tube is controlled through an optical coupling isolation.

8. A cable junction box remote switch system according to claim 1, wherein: The main power supply (301) adopts an AC / DC conversion circuit to connect to a power supply, and a front end is connected in series with an EMI filter RN112; the backup power supply (302) is composed of a lithium iron phosphate battery group and a super capacitor group in parallel; the photovoltaic supplement unit (303) is connected to the backup power supply (302) through an MPPT controller by a monocrystalline silicon solar panel; the bidirectional DC / DC module (304) is used for charge-discharge switching between the main power supply (301) and the backup power supply (302).

9. A cable junction box remote switch system according to claim 8, wherein: The super capacitor group is formed by six 2.7V / 500F capacitors in series to form a 16.2V module, and each capacitor is connected in parallel with a voltage stabilizing resistor, three groups of modules are connected to an energy storage bus through diode parallel connection; a MOSFET switch tube is connected in series in a discharge loop of the super capacitor group, and a voltage monitoring chip LTC6804 is used for controlling current on-off; a reverse flow prevention diode is connected in series between an output end of the MPPT controller and the lithium iron phosphate battery group.

10. A cable junction box remote switch system according to claim 1, wherein: The redundant drive circuit drives the same relay coil through two independent optical coupling isolation channels in parallel; two optical coupling input signals of the redundant drive circuit are checked for consistency through an XOR gate.

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