Isolated leakage overcurrent protection board, control method and device thereof and storage medium

Abstract

The embodiment of the application provides an isolated electric leakage overcurrent protection board, a control method and equipment thereof and a storage medium, and belongs to the technical field of protection circuits. The isolated electric leakage overcurrent protection board comprises an electric leakage protection circuit, an overcurrent protection circuit, a thyristor and a magnetic latching relay. The electric leakage protection circuit is used for detecting the current difference between the zero line and the live line, converting the magnetic field generated by the current difference into a first voltage signal, and outputting a high level to the thyristor when the first voltage signal reaches a preset electric leakage threshold. The overcurrent protection circuit is used for detecting the live line current of the live line, converting the magnetic field generated by the live line current into a second voltage signal, and outputting a high level to the thyristor when the second voltage signal reaches a preset overcurrent threshold. The thyristor is used for performing a shutdown operation on the magnetic latching relay according to the received high level, cutting off the zero line and the live line at the input end, and can integrate electric leakage and overcurrent protection without a micro control unit, thereby improving the anti-interference ability and safety of the circuit.

Description

Technical Field

[0001] This application relates to the field of protection circuit technology, and in particular to an isolated leakage current overcurrent protection board and its control method, device and storage medium. Background Technology

[0002] With the widespread use of electrical equipment, electrical safety accidents occur frequently. These include improper grounding of work areas, which can cause leakage of electricity from the metal casing to the ground through the human body, resulting in electric shock, and serious overcurrent or short circuits in equipment, leading to fires and other serious consequences.

[0003] Current circuit breakers can only protect against overcurrent or short circuits, but cannot effectively cut off leakage current. Meanwhile, residual current devices (RCDs) cannot effectively cut off severe overcurrent or short circuits, and therefore cannot simultaneously provide both leakage current protection and overcurrent protection.

[0004] In addition, in related technologies, protection circuits are usually controlled by microcontroller units (MCUs). In equipment with high interference, MCUs are prone to malfunctions or crashes, causing the protection function to fail and making it impossible to provide protection in subsequent operations. Summary of the Invention

[0005] The main objective of this application is to propose an isolated leakage and overcurrent protection board and its control method, device and storage medium, which integrates leakage and overcurrent protection without the need for a microcontroller unit, thereby improving the circuit's anti-interference capability and safety.

[0006] To achieve the above objectives, one aspect of this application provides an isolated leakage and overcurrent protection board, including a leakage protection circuit, an overcurrent protection circuit, a thyristor, and a magnetic latching relay;

[0007] The leakage protection circuit is used to detect the current difference between the neutral wire and the live wire, convert the magnetic field generated by the current difference into a first voltage signal, and output a high level to the thyristor when the first voltage signal reaches a preset leakage threshold.

[0008] The overcurrent protection circuit is used to detect the live wire current of the live wire, convert the magnetic field generated by the live wire current into a second voltage signal, and output a high level to the thyristor when the second voltage signal reaches a preset overcurrent threshold.

[0009] The thyristor is used to turn off the magnetic latching relay according to the received high level, cutting off the neutral and live wires at the input terminal.

[0010] In some embodiments, the leakage protection circuit includes a zero-sequence current transformer, a first sampling resistor, and a first detection chip; the overcurrent protection circuit includes a common current transformer, a second sampling resistor, and a second detection chip.

[0011] The zero-sequence current transformer is used to detect the current difference between the neutral wire and the live wire, and converts the magnetic field generated by the current difference into a first current signal.

[0012] The first sampling resistor is used to convert the first current signal into the first voltage signal;

[0013] The first detection chip is used to detect the first voltage signal. By comparing the first voltage signal with the preset leakage threshold, it outputs a high level to the thyristor when the first voltage signal reaches the preset leakage threshold.

[0014] The ordinary current transformer is used to detect the live wire current and convert the magnetic field generated by the live wire current into a second current signal.

[0015] The second sampling resistor is used to convert the second current signal into the second voltage signal;

[0016] The second detection chip is used to detect the second voltage signal. By comparing the second voltage signal with the preset overcurrent threshold, it outputs a high level to the thyristor when the second voltage signal reaches the preset overcurrent threshold.

[0017] In some embodiments, the isolated leakage overcurrent protection board further includes a step-down module, a charging circuit, a delay circuit, a voltage judgment circuit, and a differentiating circuit;

[0018] The step-down module is used to step down and split the mains power to obtain the first step-down power and the second step-down power.

[0019] The charging circuit is used to charge the driving capacitor of the magnetic latching relay according to the first step-down voltage.

[0020] The delay circuit includes a delay resistor and a delay capacitor, and the delay circuit is used to charge the delay capacitor according to the second step-down voltage;

[0021] The voltage judgment circuit is used to judge the voltage of the delay circuit. When the voltage of the delay circuit reaches a preset voltage threshold, the differential circuit controls the field-effect transistor of the magnetic latching relay to conduct once, so as to reset the magnetic latching relay.

[0022] In some embodiments, the isolated leakage current overcurrent protection board further includes a control board interface, which is used to output a continuous high level to an external device after the magnetic latching relay is turned off.

[0023] In some embodiments, the isolated leakage overcurrent protection board further includes a first rectifier circuit and a power-on status detection circuit, and the control board interface includes a first port;

[0024] The first rectifier circuit is used to rectify the live wire at the input terminal to obtain the first rectified signal;

[0025] The power-on status detection circuit includes a first current-limiting resistor and a first optocoupler. The power-on status detection circuit is used to convert the mains power access status into a first level signal and output it to the first port according to the first rectified signal through the first current-limiting resistor and the first optocoupler.

[0026] The first port is used to output the first level signal to the external device.

[0027] In some embodiments, the isolated leakage overcurrent protection board further includes a second rectifier circuit and a relay status detection circuit, and the control board interface further includes a second port;

[0028] The second rectifier circuit is used to rectify the live wire at the rear end of the magnetic latching relay to obtain a second rectified signal;

[0029] The relay status detection circuit includes a second current-limiting resistor and a second optocoupler. The relay status detection circuit is used to convert the mains power status of the magnetic latching relay into a second level signal and output it to the second port based on the second rectified signal through the second current-limiting resistor and the second optocoupler.

[0030] The second port is used to output the second level signal to the external device.

[0031] In some embodiments, the isolated leakage current overcurrent protection board further includes a third optocoupler, and the control board interface further includes a third port;

[0032] The third port is used to receive the active shutdown signal sent by the external device;

[0033] The third optocoupler is used to transmit the active turn-off signal to the thyristor so that the magnetic latching relay performs a turn-off operation, cutting off the neutral and live wires at the input terminal.

[0034] To achieve the above objectives, another aspect of this application proposes a control method for an isolated leakage overcurrent protection board, the control method comprising the following steps:

[0035] The leakage protection circuit detects the current difference between the neutral wire and the live wire, converts the magnetic field generated by the current difference into a first voltage signal, and outputs a high level to the thyristor when the first voltage signal reaches a preset leakage threshold.

[0036] The overcurrent protection circuit detects the live wire current, converts the magnetic field generated by the live wire current into a second voltage signal, and outputs a high level to the thyristor when the second voltage signal reaches a preset overcurrent threshold.

[0037] The thyristor shuts off the magnetic latching relay based on the received high level, cutting off the neutral and live wires at the input terminal.

[0038] To achieve the above objectives, another aspect of this application provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the control method described above.

[0039] To achieve the above objectives, another aspect of the embodiments of this application proposes a computer-readable storage medium storing a computer program that, when executed by a processor, implements the control method described above.

[0040] The embodiments of this application include at least the following beneficial effects: This application provides an isolated leakage current and overcurrent protection board and its control method, device and storage medium. The isolated leakage current and overcurrent protection board includes a leakage current protection circuit, an overcurrent protection circuit, a thyristor and a magnetic latching relay. The leakage current protection circuit is used to detect the current difference between the neutral wire and the live wire, convert the magnetic field generated by the current difference into a first voltage signal, and output a high level to the thyristor when the first voltage signal reaches a preset leakage current threshold. The overcurrent protection circuit is used to detect the live wire current, convert the magnetic field generated by the live wire current into a second voltage signal, and output a high level to the thyristor when the second voltage signal reaches a preset overcurrent threshold. The thyristor is used to turn off the magnetic latching relay according to the received high level, cutting off the neutral wire and the live wire at the input terminal. It can integrate leakage current and overcurrent protection, and does not require a microcontroller unit, improving the anti-interference capability and safety of the circuit. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the structure of the isolated leakage overcurrent protection board provided in the embodiments of this application;

[0042] Figure 2 This is a circuit diagram of the input terminal of the isolated leakage and overcurrent protection board provided in the embodiments of this application;

[0043] Figure 3 This is a circuit diagram of the output terminal of the isolated leakage and overcurrent protection board provided in the embodiments of this application;

[0044] Figure 4 This is a circuit diagram of the magnetic latching relay control circuit provided in the embodiments of this application;

[0045] Figure 5 This is a circuit diagram of a zero-sequence current transformer for detecting current difference provided in an embodiment of this application;

[0046] Figure 6 This is a circuit schematic diagram of the first detection chip provided in an embodiment of this application;

[0047] Figure 7 This is a circuit diagram of a common current transformer for detecting live wire current provided in an embodiment of this application;

[0048] Figure 8 This is a circuit schematic diagram of the second detection chip provided in an embodiment of this application;

[0049] Figure 9 This is a circuit schematic diagram of the step-down module provided in the embodiments of this application;

[0050] Figure 10 This is a circuit diagram of the power-on self-reset circuit provided in the embodiments of this application;

[0051] Figure 11 This is a circuit schematic diagram of the control board interface provided in an embodiment of this application;

[0052] Figure 12 This is a circuit schematic diagram of the first rectifier circuit provided in the embodiments of this application;

[0053] Figure 13 This is a circuit schematic diagram of the power-on state detection circuit provided in an embodiment of this application;

[0054] Figure 14 This is a circuit schematic diagram of the second rectifier circuit provided in the embodiments of this application;

[0055] Figure 15 This is a circuit schematic diagram of the relay status detection circuit provided in the embodiments of this application;

[0056] Figure 16 This is a circuit diagram of the active shutdown circuit provided in the embodiments of this application;

[0057] Figure 17 This is a circuit diagram of the chip power supply circuit provided in the embodiments of this application;

[0058] Figure 18 This is a circuit schematic diagram of the TP test point provided in the embodiments of this application;

[0059] Figure 19 This is a flowchart of the control method for the isolated leakage overcurrent protection board provided in the embodiments of this application;

[0060] Figure 20 This is a schematic diagram of the hardware structure of the electronic device provided in the embodiments of this application. Detailed Implementation

[0061] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit it. In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with those of this application; they are merely examples of apparatuses and methods consistent with some aspects of the embodiments of this application as detailed in the appended claims.

[0062] It is understood that the terms “first,” “second,” etc., used in this application may be used herein to describe various concepts, but unless otherwise stated, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another. For example, without departing from the scope of the embodiments of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the words “if,” “when,” or “in response to a determination” as used herein may be interpreted as “when…” or “when…” or “in response to a determination.”

[0063] As used in this application, the terms "at least one", "multiple", "each", "any", etc., "at least one" includes one, two or more, "multiple" includes two or more, "each" refers to each of the corresponding multiples, and "any" refers to any one of the multiples.

[0064] Before providing a detailed description of the embodiments of this application, the terms used in the embodiments of this application will be explained as follows.

[0065] Network tags: Network tags are a method used in circuit schematics to simplify wiring. By adding a name tag to one end of a wire and then adding a name tag with the same name to the other end of a wire, the electrical logic is connected, thereby improving the readability and neatness of the circuit diagram.

[0066] 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 application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0067] The control method for an isolated leakage current overcurrent protection board provided in this application relates to the field of protection circuit technology. The control method for the isolated leakage current overcurrent protection board provided in this application can be applied to a terminal, a server, or software running on a terminal or server. In some embodiments, the terminal can be a smartphone, tablet, laptop, desktop computer, smart speaker, smartwatch, or vehicle terminal, but is not limited thereto; the server can be configured as an independent physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server providing basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, CDN, and big data and artificial intelligence platforms. The server can also be a node server in a blockchain network; the software can be an application implementing the control method for the isolated leakage current overcurrent protection board, but is not limited to the above forms.

[0068] This application can be used in a wide variety of general-purpose or special-purpose computer system environments or configurations. Examples include: personal computers, server computers, handheld or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, set-top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, and distributed computing environments including any of the above systems or devices. This application can be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform specific tasks or implement specific abstract data types. This application can also be practiced in distributed computing environments where tasks are performed by remote processing devices connected via a communication network. In distributed computing environments, program modules can reside in local and remote computer storage media, including storage devices.

[0069] Reference Figure 1 , Figure 1 This is a schematic diagram of the structure of the isolated leakage current and overcurrent protection board provided in the embodiment of this application. The isolated leakage current and overcurrent protection board includes a leakage current protection circuit, an overcurrent protection circuit, a thyristor, and a magnetic latching relay.

[0070] The leakage protection circuit is used to detect the current difference between the neutral wire and the live wire, convert the magnetic field generated by the current difference into a first voltage signal, and output a high level to the thyristor when the first voltage signal reaches the preset leakage threshold.

[0071] The overcurrent protection circuit is used to detect the live wire current, convert the magnetic field generated by the live wire current into a second voltage signal, and output a high level to the thyristor when the second voltage signal reaches the preset overcurrent threshold.

[0072] The thyristor is used to turn off the magnetic latching relay based on the received high level, cutting off the neutral and live wires at the input terminal.

[0073] Specifically, such as Figure 2 As shown, the high-current onboard connector J2 is used as the input terminal of the isolated leakage and overcurrent protection board, connected to the neutral and live wires. In the circuit schematic, pins 1 and 3 of the high-current onboard connector are connected via the network label LINE_NEUTRAL, and pin 4 is connected via the network label LINE_HOT to a pin in the circuit with the same network label. Figure 3 As shown, the high-current onboard connector J3 is used as the output terminal of the isolated leakage and overcurrent protection board and connected to the high-power equipment.

[0074] Furthermore, such as Figure 1 As shown, a leakage current protection circuit measures the current difference between the two AC power lines (live and neutral) at the input terminal to determine if there is current leakage. If there is current leakage, the current difference between the neutral and live wires will not be zero, thus generating a magnetic field in the power lines. The leakage current protection circuit converts this magnetic field into a first voltage signal. When this first voltage signal reaches a preset leakage threshold, it indicates that the leakage current has reached a certain intensity. Therefore, the leakage current protection circuit outputs a high level to the thyristor. Figure 4 As shown, a unidirectional thyristor PCR606 is used as thyristor D8. When thyristor D8 receives a high level, thyristor D8 is turned on, driving magnetic latching relay HFE10 to cut off the neutral and live wires at the input terminal.

[0075] Meanwhile, the overcurrent protection circuit detects the current of a single AC power line (live wire). The core of overcurrent protection is to detect whether the total current in the circuit exceeds the safety threshold. The live wire current is a direct reflection of the total current. By detecting the live wire current, it is determined whether there is an overcurrent. If there is an overcurrent, the magnetic field generated by the live wire current is converted into a second voltage signal. When the second voltage signal reaches the preset overcurrent threshold, it means that the current on the live wire has reached a certain intensity. Therefore, the overcurrent protection circuit outputs a high level to the thyristor D8.

[0076] It should be noted that, in order to ensure accuracy in high-power scenarios and to control the size of the structure, the embodiments of this application adopt an isolated measurement mode to reduce power consumption so that it can be applied to higher-power devices.

[0077] This embodiment integrates leakage protection and overcurrent protection using hardware circuitry. The hardware circuitry does not rely on the logic control of the microcontroller unit, thus avoiding the risk of program crashes or freezes and improving the anti-interference capability and safety of the protection circuitry.

[0078] In some embodiments, the leakage protection circuit includes a zero-sequence current transformer, a first sampling resistor, and a first detection chip, while the overcurrent protection circuit includes a general current transformer, a second sampling resistor, and a second detection chip.

[0079] Zero-sequence current transformers are used to detect the current difference between the neutral wire and the live wire, and convert the magnetic field generated by the current difference into a first current signal.

[0080] The first sampling resistor is used to convert the first current signal into a first voltage signal.

[0081] The first detection chip is used to detect the first voltage signal. By comparing the first voltage signal with a preset leakage threshold, a high level is output to the thyristor when the first voltage signal reaches the preset leakage threshold.

[0082] A standard current transformer is used to detect the live wire current and convert the magnetic field generated by the live wire current into a second current signal.

[0083] The second sampling resistor is used to convert the second current signal into a second voltage signal.

[0084] The second detection chip is used to detect the second voltage signal. By comparing the second voltage signal with a preset overcurrent threshold, it outputs a high level to the thyristor when the second voltage signal reaches the preset overcurrent threshold.

[0085] Specifically, refer to Figure 5 The leakage protection circuit uses an isolated zero-sequence current transformer J1 to detect the current difference between the neutral and live wires to determine whether there is current leakage from the downstream power terminal. When leakage occurs, there will be a current difference between the neutral and live wires, which will cause the magnetic field generated by the power line to not be completely canceled. The zero-sequence current transformer is used to convert the generated magnetic field into a first current signal, and a sampling resistor R4 (i.e., the first sampling resistor) is used to convert the first current signal into a first voltage signal.

[0086] After obtaining the first voltage signal, as Figure 6 As shown, the leakage protection circuit uses the first detection chip U2 to detect the first voltage signal. When the first voltage signal reaches the preset leakage threshold, the first detection chip U2 sends a high level to the thyristor D8 through pin 5 to turn off the two magnetic latching relays (K1 and K2), thereby cutting off the neutral and live wires at the input terminal.

[0087] Overcurrent detection solutions in related technologies typically involve directly connecting a sampling resistor in series in the circuit and indirectly calculating the current by measuring the voltage across the resistor. This approach suffers from severe heat generation in high-power devices, affecting system stability. To address the issue of excessive resistor heating during overcurrent detection under high current conditions, this embodiment first uses a current transformer to generate an induced current, and then converts this induced current into a voltage through the sampling resistor. As can be understood, a current transformer is a non-contact current sensing device that can convert large currents into smaller ones, enabling the detection of large currents without causing severe heat generation.

[0088] For example, refer to Figure 7 The overcurrent protection circuit uses an isolated ordinary current transformer ZHT123A-CP to detect the current of the live wire, obtain the current of the downstream power supply terminal, convert it into a second current signal through an ordinary current transformer, and then use a sampling resistor R2 (i.e., the second sampling resistor) to perform voltage conversion to obtain a second voltage signal.

[0089] After obtaining the second voltage signal, as follows Figure 8 As shown, the overcurrent protection circuit uses the second detection chip U7 to detect the second voltage signal. When the second voltage signal reaches the preset overcurrent threshold, the second detection chip U7 sends a high level to the thyristor D8 through pin 5, which turns off the two magnetic latching relays (K1 and K2), thereby cutting off the neutral and live wires at the input terminal.

[0090] In this embodiment, the use of isolated sensors ensures the safety of the low-voltage circuitry, guarantees measurement accuracy, and integrates overcurrent and leakage protection onto the same board. Pure analog circuitry control avoids the risk of software malfunctions associated with using an MCU. Furthermore, for high-power applications, this reduces heat generation, improves product safety, and lowers overall device power consumption.

[0091] Optionally, the FM2147 chip can be used as the first detection chip U2 and the second detection chip U7. The FM2147 chip has a fast response time and can quickly trigger protection action when leakage or overcurrent is detected.

[0092] In some embodiments, the isolated leakage overcurrent protection board further includes a step-down module, a charging circuit, a delay circuit, a voltage judgment circuit, and a differentiating circuit.

[0093] The step-down module is used to step down and split the AC mains power to obtain the first step-down voltage and the second step-down voltage.

[0094] The charging circuit is used to charge the drive capacitor of the first step-down magnetic latching relay.

[0095] The delay circuit includes a delay resistor and a delay capacitor, and is used to charge the delay capacitor according to the second step-down voltage.

[0096] The voltage judgment circuit is used to judge the voltage of the delay circuit. When the voltage of the delay circuit reaches the preset voltage threshold, the field-effect transistor of the magnetic latching relay is controlled by the differentiating circuit to conduct once, so as to reset the magnetic latching relay.

[0097] Specifically, considering that manual reset of the switch is currently required after the protection is triggered, this embodiment designs a power-on self-reset circuit with automatic power-on reset protection function.

[0098] Reference Figure 9 The isolated leakage and overcurrent protection board also includes a step-down module U6. When the mains power is input, the 220V mains power is reduced to 12V by the step-down module U6. The stepped-down mains power is then split into the first stepped-down power and the second stepped-down power.

[0099] In this embodiment, a charging circuit is formed by a diode D1 and a driving capacitor C1. The charging circuit charges the driving capacitor C1 of the magnetic latching relay according to the first step-down voltage, and the driving capacitor C1 provides the energy required for the operation of the magnetic latching relay.

[0100] The other 12V (i.e., the second step-down voltage) is charged through an RC delay circuit, awaiting the charging of the drive capacitor. The RC delay circuit delays the triggering of the reset action, ensuring that the reset occurs only after the drive capacitor is fully charged. For example, refer to... Figure 10 The RC delay circuit consists of a delay resistor R7 and a delay capacitor C9. By charging the delay capacitor C9, the voltage of the RC delay circuit is increased.

[0101] When the voltage in the RC delay circuit rises, the voltage judgment circuit judges the voltage by a preset voltage threshold. When the voltage in the RC delay circuit reaches the voltage threshold, a capacitor C7 is used as a differentiating circuit to conduct the field-effect transistor Q2 of the magnetic latching relay once to trigger the single switching action of the magnetic latching relay, so that the magnetic latching relay is reset and waits for the next protection.

[0102] Alternatively, the voltage detection circuit can use a transistor and a Zener diode for detection, such as... Figure 10 As shown, the voltage detection circuit consists of transistor Q1 and Zener diode D5.

[0103] In this embodiment, the power-on self-recovery scheme is controlled by a purely hardware circuit. This ensures that the drive capacitor allows the magnetic latching relay to recover normally, and the materials used are very simple, reducing costs. This embodiment provides convenience for equipment recovery through the power-on self-recovery function, eliminating the need for manual intervention.

[0104] In some embodiments, the isolated leakage current overcurrent protection board also includes a control board interface for outputting a continuous high level to an external device after the magnetic latching relay is turned off.

[0105] Specifically, refer to Figure 11 The isolated leakage current overcurrent protection board also includes a control board interface J4. The control board interface J4 is used to output a continuous high level to external devices after the magnetic latching relay is turned off, thereby sending the status of whether the mains power is present and whether the magnetic latching relay is turned off when the mains power is present to other devices, so that the external status can read the protection status of the isolated leakage current overcurrent protection board.

[0106] In this embodiment, by transmitting a signal to an external device after the protection action is triggered, the status of the isolated leakage current overcurrent protection board can be monitored in real time so as to handle accidents in a timely manner.

[0107] In some embodiments, the isolated leakage current overcurrent protection board further includes a first rectifier circuit and a power-on status detection circuit, and the control board interface includes a first port.

[0108] The first rectifier circuit is used to rectify the live wire at the input terminal to obtain the first rectified signal.

[0109] The power-on status detection circuit includes a first current-limiting resistor and a first optocoupler. The power-on status detection circuit is used to convert the mains power access status into a first level signal and output it to the first port based on the first rectified signal through the first current-limiting resistor and the first optocoupler.

[0110] The first port is used to output a first-level signal to an external device.

[0111] Specifically, the isolated leakage current and overcurrent protection board also includes a first rectifier circuit and a power-on status detection circuit. The control board interface includes a first port. After the live wire at the input end is rectified by the first rectifier circuit, the power-on status detection circuit outputs the mains power connection status to the external device in the form of a level through the first port.

[0112] For example, refer to Figure 12 The AC power input at pin 4, LINE_HOT, is converted into DC power output at pin 1, 220IN (i.e., the first rectified signal), by a single-phase bridge rectifier U8.

[0113] like Figure 13As shown, the DC power 220IN is converted into a first level signal SIN_220V through the first current-limiting resistor R16 and the first optocoupler U9. The first level signal SIN_220V is output from the first port to the external device through pin 3 of the control board interface J4.

[0114] In some embodiments, the isolated leakage overcurrent protection board further includes a second rectifier circuit and a relay status detection circuit, and the control board interface further includes a second port.

[0115] The second rectifier circuit is used to rectify the live wire at the rear of the magnetic latching relay to obtain the second rectified signal.

[0116] The relay status detection circuit includes a second current-limiting resistor and a second optocoupler. The relay status detection circuit is used to convert the mains power status of the magnetic latching relay into a second level signal and output it to the second port based on the second rectified signal through the second current-limiting resistor and the second optocoupler.

[0117] The second port is used to output a second-level signal to an external device.

[0118] Specifically, the isolated leakage current and overcurrent protection board also includes a second rectifier circuit and a relay status detection circuit. The control board interface also includes a second port. After the live wire at the rear end of the magnetic latching relay is rectified by the second rectifier circuit, the relay status detection circuit outputs the mains power status at the rear end of the relay to the external device in the form of a level through the second port.

[0119] For example, refer to Figure 14 The live AC power input at pin 3, LINE_HOT_LLL, is converted into DC power output at pin 1, 220DC (i.e., the second rectified signal), by a single-phase bridge rectifier U1.

[0120] like Figure 15 As shown, the 220DC DC power is converted into a second-level signal SIN_Relays through the second current-limiting resistor R18 and the second optocoupler U3. The second-level signal SIN_Relays is output to the external device from the second port through pin 2 of the control board interface J4.

[0121] In some embodiments, the isolated leakage current overcurrent protection board further includes a third optocoupler, and the control board interface further includes a third port.

[0122] The third port is used to receive active shutdown signals sent by external devices.

[0123] The third optocoupler is used to transmit the active turn-off signal to the thyristor so that the magnetic latching relay can perform a turn-off operation, cutting off the neutral and live wires at the input terminal.

[0124] Specifically, the isolated leakage current and overcurrent protection board also includes a third optocoupler, and the control board interface also includes a third port. External devices transmit an active shutdown signal to the thyristor through the third optocoupler, causing the driven magnetic latching relay to perform a shutdown operation, thereby enabling the external device to shut down the isolated leakage current and overcurrent protection board.

[0125] For example, refer to Figure 11 The active shutdown signal CON_Relays sent by the external device is transmitted from pin 4 of the control board interface J4 to the third optocoupler U5 via the third port. For example... Figure 16 As shown, the active turn-off signal CON_Relays is converted into a turn-off signal CON Close through resistor R15, the third optocoupler U5, and resistor R19 and transmitted to thyristor D8 to turn off the magnetic latching relay, thereby cutting off the neutral and live wires at the input terminal.

[0126] Reference Figure 17 In some embodiments, the isolated leakage and overcurrent protection board also includes a chip power supply circuit. This circuit steps down the 12V voltage to 5V via a voltage regulator chip U4, supplying power to the FM2147 chips in the leakage protection circuit and overcurrent protection circuit through pins 2 and 4 respectively.

[0127] Reference Figure 18 In some embodiments, the isolated leakage overcurrent protection board also includes seven TP test points, which can be measured with equipment such as an oscilloscope to ensure proper circuit operation.

[0128] Figure 19 This is an optional flowchart of the control method for the isolated leakage overcurrent protection board provided in the embodiments of this application. Figure 19 The method may include, but is not limited to, steps S101 to S103.

[0129] Step S101: The leakage protection circuit detects the current difference between the neutral wire and the live wire, converts the magnetic field generated by the current difference into a first voltage signal, and outputs a high level to the thyristor when the first voltage signal reaches the preset leakage threshold.

[0130] Step S102: The overcurrent protection circuit detects the live wire current, converts the magnetic field generated by the live wire current into a second voltage signal, and outputs a high level to the thyristor when the second voltage signal reaches the preset overcurrent threshold.

[0131] In step S103, the thyristor turns off the magnetic latching relay based on the received high level, cutting off the neutral and live wires at the input terminal.

[0132] The solutions of the embodiments of this application will be described in detail and explained below with reference to specific application examples.

[0133] Taking the CZ100 tethered drone as an example, the ground-based tethered terminal requires 220V AC mains power, and its all-metal structure poses a risk of leakage. An isolated leakage and overcurrent protection board can be connected to the device's power input. Under extreme conditions, if leakage occurs, the leakage protection circuit detects the current difference between the neutral and live wires at the device's input to determine if leakage has occurred.

[0134] Specifically, the leakage protection circuit converts the magnetic field generated by the current difference into a first voltage signal and compares the first voltage signal with a preset leakage threshold. If the first voltage signal is equal to or greater than the leakage threshold, it is determined to be a leakage. The leakage protection circuit outputs a high level to trigger the thyristor to conduct. After the thyristor conducts, it drives the magnetic latching relay to cut off the neutral and live wires at the input terminal, stop the power supply, and prevent the neutral and live wires of the subsequent circuit from touching the metal casing, which could lead to AC leakage and electric shock to the human body, thus achieving leakage protection.

[0135] Alternatively, if the device experiences a short circuit under extreme conditions, the current will rise sharply, and the overcurrent protection circuit can detect the live wire current to determine whether a short circuit has occurred.

[0136] Specifically, the overcurrent protection circuit converts the magnetic field generated by the live wire current into a second voltage signal and compares the second voltage signal with a preset overcurrent threshold. If the second voltage signal is equal to or greater than the overcurrent threshold, it is determined to be an overcurrent. The overcurrent protection circuit outputs a high level to trigger the thyristor to conduct. After the thyristor conducts, it drives the magnetic latching relay to cut off the neutral and live wires at the input terminal, stop the power supply, and prevent the continuous damage to the equipment caused by the short circuit between the live and neutral wires in the subsequent stage, thus achieving overcurrent protection.

[0137] The isolated leakage and overcurrent protection board can also transmit protection information to other devices via voltage levels after protection is activated, allowing other devices to perform corresponding operations.

[0138] Once the protection action is completed and the fault has been resolved, the isolated leakage and overcurrent protection board can perform self-reset upon power-up without manual intervention.

[0139] In summary, the isolated leakage and overcurrent protection board provided in this application integrates leakage protection, overcurrent protection, and power-on self-reset functions. It does not require MCU control, can be used in highly interference-prone environments, and its overcurrent detection scheme generates little heat, making it suitable for high-power devices. Furthermore, this isolated leakage and overcurrent protection board allows external devices to read the protection status.

[0140] This application also provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the control method of the isolated leakage current overcurrent protection board described above. This electronic device can be any smart terminal, including tablet computers, in-vehicle computers, etc.

[0141] It is understood that the content of the above method embodiments is applicable to this device embodiment. The specific functions implemented by this device embodiment are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0142] Please see Figure 20 , Figure 20 The hardware structure of an electronic device according to another embodiment is illustrated. The electronic device includes:

[0143] The processor 901 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this application.

[0144] The memory 902 can be implemented as a read-only memory (ROM), static storage device, dynamic storage device, or random access memory (RAM). The memory 902 can store the operating system and other application programs. When the technical solutions provided in the embodiments of this specification are implemented through software or firmware, the relevant program code is stored in the memory 902, and the processor 901 calls and executes the control method of the isolated leakage current and overcurrent protection board of the embodiments of this application.

[0145] The input / output interface 903 is used to implement information input and output.

[0146] The communication interface 904 is used to enable communication and interaction between this device and other devices. Communication can be achieved through wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.).

[0147] Bus 905 transmits information between various components of the device (e.g., processor 901, memory 902, input / output interface 903, and communication interface 904).

[0148] The processor 901, memory 902, input / output interface 903, and communication interface 904 are connected to each other within the device via bus 905.

[0149] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the control method of the isolated leakage current overcurrent protection board described above.

[0150] It is understood that the content of the above method embodiments is applicable to this storage medium embodiment. The specific functions implemented in this storage medium embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments.

[0151] Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. Furthermore, memory may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, memory may optionally include memory remotely located relative to the processor, and these remote memories can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0152] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0153] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of this application, and may include more or fewer steps than shown, or combine certain steps, or different steps.

[0154] The system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0155] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0156] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0157] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.

Claims

1. An isolated leakage overcurrent protection board, characterized in that, The leakage protection circuit, the overcurrent protection circuit, the thyristor and the magnetic latching relay are included. The leakage protection circuit is used for detecting the current difference between the zero line and the live line, converting the magnetic field generated by the current difference into a first voltage signal, and outputting a high level to the thyristor when the first voltage signal reaches a preset leakage threshold. The overcurrent protection circuit is used for detecting the live line current of the live line, converting the magnetic field generated by the live line current into a second voltage signal, and outputting a high level to the thyristor when the second voltage signal reaches a preset overcurrent threshold. The thyristor is used for performing shutdown operation on the magnetic latching relay according to the received high level, and cutting off the zero line and the live line of the input end. The isolation type leakage and overcurrent protection board further includes a voltage reduction module, a charging circuit, a delay circuit, a voltage judgment circuit and a differential circuit. The voltage reduction module is used for performing voltage reduction and shunt processing on the commercial power to obtain first and second voltage reduction electricity. The charging circuit is used for charging the driving capacitor of the magnetic latching relay according to the first voltage reduction electricity. The delay circuit includes a delay resistor and a delay capacitor, and the delay circuit is used for charging the delay capacitor according to the second voltage reduction electricity. The voltage judgment circuit is used for judging the voltage of the delay circuit, and when the voltage of the delay circuit reaches a preset voltage threshold, the field effect transistor of the magnetic latching relay is controlled to be turned on once by the differential circuit, so that the magnetic latching relay is reset.

2. The isolated electrical leakage and overcurrent protection panel according to claim 1, wherein, The leakage protection circuit includes a zero sequence current transformer, a first sampling resistor and a first detection chip, and the overcurrent protection circuit includes a general current transformer, a second sampling resistor and a second detection chip. The zero sequence current transformer is used for detecting the current difference between the zero line and the live line, and converting the magnetic field generated by the current difference into a first current signal. The first sampling resistor is used for converting the first current signal into the first voltage signal. The first detection chip is used for detecting the first voltage signal, and outputting a high level to the thyristor when the first voltage signal reaches the preset leakage threshold by comparing the first voltage signal with the preset leakage threshold. The general current transformer is used for detecting the live line current of the live line, and converting the magnetic field generated by the live line current into a second current signal. The second sampling resistor is used for converting the second current signal into the second voltage signal. The second detection chip is used for detecting the second voltage signal, and outputting a high level to the thyristor when the second voltage signal reaches the preset overcurrent threshold by comparing the second voltage signal with the preset overcurrent threshold.

3. The isolated electrical fault current protection panel of claim 1, wherein, The isolation type leakage and overcurrent protection board further includes a control board interface, which is used for outputting a continuous high level to an external device after the magnetic latching relay is turned off.

4. The isolated electrical overcurrent protection panel of claim 3, wherein, The isolation type leakage and overcurrent protection board further includes a first rectifier circuit and a power-on state detection circuit, and the control board interface includes a first port. The first rectifier circuit is used for rectifying the live line of the input end to obtain a first rectified signal. The power-on state detection circuit includes a first current-limiting resistor and a first optocoupler, and is configured to convert a mains power access state into a first level signal output to the first port according to the first rectified signal via the first current-limiting resistor and the first optocoupler. The first port is configured to output the first level signal to the external device.

5. The isolated electrical overcurrent protection panel of claim 3, wherein, The isolated leakage and overcurrent protection board further includes a second rectification circuit and a relay state detection circuit, and the control board interface further includes a second port. The second rectification circuit is configured to rectify a hot line at a back end of the magnetic latching relay to obtain a second rectified signal. The relay state detection circuit includes a second current-limiting resistor and a second optocoupler, and is configured to convert a mains power condition at the back end of the magnetic latching relay into a second level signal output to the second port according to the second rectified signal via the second current-limiting resistor and the second optocoupler. The second port is configured to output the second level signal to the external device.

6. The isolated electrical overcurrent protection panel of claim 3, wherein, The isolated leakage and overcurrent protection board further includes a third optocoupler, and the control board interface further includes a third port. The third port is configured to receive an active shutdown signal sent by the external device. The third optocoupler is configured to transmit the active shutdown signal to the thyristor, so that the magnetic latching relay performs a shutdown operation to cut off the zero line and the hot line at the input end.

7. A control method of an isolated leakage current overcurrent protection board, characterized by, The control method includes the following steps: detecting a current difference between the zero line and the hot line by a leakage protection circuit, converting a magnetic field generated by the current difference into a first voltage signal, and outputting a high level to the thyristor when the first voltage signal reaches a preset leakage threshold value; detecting a hot line current of the hot line by an overcurrent protection circuit, converting a magnetic field generated by the hot line current into a second voltage signal, and outputting a high level to the thyristor when the second voltage signal reaches a preset overcurrent threshold value; performing a shutdown operation on the magnetic latching relay by the thyristor according to the received high level, and cutting off the zero line and the hot line at the input end; performing voltage reduction and shunt processing on the mains power by a voltage reduction module to obtain first reduced voltage and second reduced voltage; charging the driving capacitor of the magnetic latching relay by a charging circuit according to the first reduced voltage; charging the delay capacitor by a delay circuit according to the second reduced voltage; judging the voltage of the delay circuit by a voltage judgment circuit, and controlling the field effect transistor of the magnetic latching relay to conduct once by a differential circuit when the voltage of the delay circuit reaches a preset voltage threshold value, so that the magnetic latching relay is reset.

8. An electronic device, comprising: The electronic device includes a memory and a processor, the memory stores a computer program, and the processor implements the control method of claim 7 when executing the computer program.

9. A computer-readable storage medium storing a computer program, the computer program comprising instructions that, when executed by a computer, cause the computer to perform the method of any one of claims 1 to 8. The computer program is executed by the processor to implement the control method of claim 7.

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