An electric drop-out fuse low-power consumption current detection system and method

Abstract

The application discloses a kind of low-power current detection system and method of electric drop-out fuse, belong to electric drop-out fuse technical field, including microcontroller, current transformer, rectifier bridge, small capacity capacitor, first comparator, farad capacitor, wireless communication module, LED indicator, GPIO interface, ADC module, flow-break comparator, capacitor charging circuit and power management unit, current transformer is powered from low to 0.3A line current, is built by small capacity capacitor after rectification Fast voltage, first comparator drives PMOS tube to charge and power supply for farad capacitor, flow-break comparator is directly connected with the external interrupt pin of microcontroller, instantaneously wakes up system when line current drops suddenly, on the method, after power-on initialization, enter main loop, judge GPIO initialization, flow-break, power-on current, alarm, capacitor full power wake-up and manual wake-up flag in turn, execute data acquisition, wireless transmission or capacitor charging, the present application does not need external battery, realize ultra-low power consumption and flow-break instantaneous response.

Description

Technical Field

[0001] This invention relates to the field of electrically operated drop-out fuse technology, specifically to a low-power current detection system and method for electrically operated drop-out fuses. Background Technology

[0002] Regarding the existing patent for a fuse tube and electric drop-out fuse with current detection function (authorization announcement number CN219370961U), due to the need to consider the real-time signaling when the primary current is very small (usually <0.4A) and the constraints of the overall product size, which limit the use of large-capacity batteries and the need to meet strict low-power requirements, only a trigger circuit is set when the fuse blows (fewer components mean lower power consumption). However, in actual product installation, because the primary current is very small, the entire PCBA requires a long time to charge the internal supercapacitor to the wake-up threshold. Although this does not affect the main function of the product, it will cause confusion in actual installation work, since waiting for this charging time for every installation is impractical.

[0003] To address the aforementioned issues, modifications were made to the original PCB circuit. A power-on wake-up circuit was added to the original circuit. For the system, when the current changes from 0 to present (>=0.1A), a system wake-up is triggered to send a data frame. Although this increases the complexity and power consumption of the system circuit, by selecting components suitable for strictly low-power scenarios, it is still possible to balance cost, power consumption, and functionality while making appropriate modifications to the original circuit.

[0004] Meanwhile, in order to meet the needs of rural power grid applications, the original current detection range of 1A-50A is no longer sufficient to meet the accuracy requirements of the lower limit value of the detection. The minimum current detection value needs to reach the corresponding detection range of 0.3A-50A.

[0005] Furthermore, existing fuses require mercury switches during the tripping process. During tripping, the capacitor must first be charged before the trip can be triggered, resulting in a long wake-up time and insufficiently sensitive and rapid triggering response. Current conventional methods merely shorten the charging time by improving the capacitor's application requirements, characteristics, and charging methods. Mercury switches also suffer from: 1. slow triggering response; 2. limited acceleration recognition conditions; 3. poor overall stability and minimal power consumption reduction during application.

[0006] To address this, the present invention employs an integrated data acquisition unit, which uses the MODBUS protocol and overall setup logic program to solve the aforementioned technical problems and achieve independent monitoring and identification of individual phase currents. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art and provide a low-power current detection system and method for electric drop-out fuses, thereby solving the problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a low-power current detection system and method for an electrically operated drop-out fuse, comprising a microcontroller; a current transformer for sensing line current; a rectifier bridge connected to the secondary side of the current transformer for converting alternating current into pulsating direct current; a small-capacity capacitor connected to the output of the rectifier bridge for rapidly establishing voltage under line currents as low as 0.3A, wherein the capacitance value of the small-capacity capacitor and the capacitance value of the farad capacitor satisfy: C_small (small capacitance value) ≤ 0.1 × C_farad (large capacitance value), so that the small-capacity capacitor can establish a voltage exceeding the reference voltage within 100ms when the line current is ≥ 0.3A; a first comparator connected to the output of the small-capacity capacitor for generating a start signal when the voltage of the small-capacity capacitor exceeds the reference voltage; and a farad capacitor connected to the output of the first comparator via a PMOS transistor for storing electrical energy and supplying power to the system. The system includes: a wireless communication module connected to the microcontroller for data transmission and reception; LED indicators to show the wireless module's detection error or operating status; a GPIO interface for connecting external devices and detecting input signals; an ADC module integrated within the microcontroller or set up independently externally for acquiring current or voltage signals; a current interruption comparator whose power supply is directly connected to the output of the rectifier bridge or the positive terminal of the small-capacity capacitor, used to detect current interruption events and generate a falling-edge interrupt, with its output directly connected to the external interrupt pin of the microcontroller, and the output signal of the current interruption comparator independent of the charging state of the supercapacitor; a capacitor charging circuit for charging the current interruption detection capacitor; and a power management unit controlled by the microcontroller for switching between sleep and wake-up modes. The output signal of the current interruption comparator is independent of the charging state of the supercapacitor and can instantly wake up the microcontroller when the line current drops sharply below a threshold.

[0009] Preferably, the wireless communication module is an NRF24L01 chip, and the microcontroller communicates with it through an SPI interface. The microcontroller has a built-in or external memory, which stores a computer program. When the program is executed by the microcontroller, it realizes the current detection of the electric drop-out fuse.

[0010] Preferably, the interrupt comparator is a VC2 comparator, whose falling edge output is used to wake up the microcontroller.

[0011] Preferably, the current transformer, under line current as low as 0.3A, activates the PMOS transistor through the small-capacity capacitor and the first comparator to charge the farad capacitor, enabling the system to obtain operating power from the weak line current.

[0012] Preferably, in the fourth step, the interruption delay detection is achieved by initializing a timer and calling a sampling function.

[0013] Preferably, in the fifth step, the first type of data is the data packet sent when the system is first powered on and current is detected (i.e., the device has just been powered on and started, and there is current flowing through the external load circuit).

[0014] Preferably, in the sixth step, the second type of data is the data packet sent when the system detects a current interruption alarm event (e.g., the external load circuit current suddenly becomes zero or falls below a threshold).

[0015] Preferably, in the seventh step, after the current interruption detection capacitor has finished charging, the wake-up packet sent has the same format as the wake-up packet in step S5, and the current data sent includes real-time sampled values.

[0016] Preferably, in the eighth step, the manual test function includes: LED indicator self-test, wireless communication module sending self-test data packet, and supercapacitor remaining power detection.

[0017] Preferably, in the tenth step, the wake-up source of the sleep mode includes: falling edge interrupt of the current cutoff comparator, level change interrupt of the wake-up pin when the capacitor is fully charged, external interrupt of manual key input, and periodic timer interrupt.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] 1. The problem of insufficient accuracy in low current detection: The original detection range of 1A–50A has been expanded to 0.3A–50A, which significantly improves the current monitoring capability in low-load scenarios of rural power grids and meets the accurate acquisition requirement of the lower limit of 0.3A.

[0020] 2. The problem of slow fuse tripping trigger response and long wake-up time: Abandoning the traditional mercury switch and the triggering method that relies on capacitor pre-charging, the system achieves rapid identification and wake-up of interruption events through an integrated data acquisition unit and optimized logic program, which greatly shortens the trigger response time.

[0021] 3. Stability and power consumption issues caused by inherent defects of mercury switches: The drawbacks of mercury switches, such as slow trigger response, limited acceleration recognition, poor overall stability, and insufficient power consumption reduction, are eliminated. Solid-state electronic detection and interrupt wake-up mechanisms are adopted to improve system reliability and reduce operating power consumption; the need for independent monitoring of single-phase current: Through integrated acquisition unit and MODBUS protocol communication, independent identification and monitoring of current in individual phases can be achieved, which facilitates distributed deployment and remote data interaction in rural power grids. Attached Figure Description

[0022] Figure 1 This is a circuit block diagram of the present invention;

[0023] Figure 2A This is the first part of the system flowchart of the present invention;

[0024] Figure 2B This is the second part of the system flowchart of the present invention;

[0025] Figure 2C This is the third part of the system flowchart of the present invention;

[0026] Figure 2D This is the fourth part of the system flowchart of the present invention;

[0027] Figure 3 for Figure 2A A schematic diagram of the startup and self-test phases in the process;

[0028] Figure 4 for Figures 2A to 2B A schematic diagram of the beginning phase of the main loop in the code;

[0029] Figure 5 for Figures 2A to 2C A partial schematic diagram of alarm flag processing within the main loop;

[0030] Figure 6 for Figure 2B A partial schematic diagram of the fully charged capacitor wake-up process in the image;

[0031] Figure 7 for Figure 2C A partial schematic diagram of the manual wake-up flag processing in the image;

[0032] Figure 8 for Figures 2A to 2C A partial schematic diagram of pin detection and judgment within the main loop;

[0033] Figure 9 for Figure 2D A partial schematic diagram of the system's low-power sleep and wake-up mechanism;

[0034] Figure 10 This is a circuit diagram of the present invention;

[0035] Figure 11 for Figure 10 The main control circuit diagram;

[0036] Figure 12 for Figure 10 Circuit diagram of the reset and wake-up section;

[0037] Figure 13 for Figure 10 Circuit diagram of the battery voltage detection and current interruption alarm section;

[0038] Figure 14 for Figure 10 Circuit diagram of the current energy harvesting and energy storage management section;

[0039] Figure 15 for Figure 10 The circuit diagram of the wireless module interface and debugging interface. Detailed Implementation

[0040] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0041] Example 1

[0042] like Figure 1-9 As shown, this embodiment discloses a low-power current detection system and method for an electrically operated drop-out fuse, including a microcontroller, a current transformer, a rectifier bridge, a small-capacity capacitor, a first comparator, a supercapacitor, a wireless communication module, an LED indicator, a GPIO interface, an ADC module, a current interruption comparator, a capacitor charging circuit, and a power management unit. The current transformer senses and draws power from a line current as low as 0.3A. After rectification, the voltage is quickly established by the small-capacity capacitor. After the voltage reaches the target, the first comparator charges the supercapacitor through a PMOS transistor and supplies power to the system. The current interruption comparator is directly connected to the external interrupt pin of the microcontroller, which can instantly wake up the microcontroller from sleep when the line current drops sharply.

[0043] In terms of methodology, after the system is powered on and initialized, it enters the main loop and sequentially judges the GPIO initialization flag, current cut-off flag, power-on current flag, alarm flag, capacitor full charge wake-up flag, and manual wake-up flag. Based on the flag, it performs corresponding data acquisition, wireless transmission, or capacitor charging operations. When there is no task, it shuts down peripherals, configures GPIO to sleep and enables the current cut-off comparator, enters deep low-power mode, and is woken up by the falling edge of the current cut-off or by a manual button.

[0044] In this invention, the microcontroller serves as the core control unit. This embodiment uses the CW32L011K8U6 low-power ARM Cortex-M0+ microcontroller, which has a maximum operating frequency of 96MHz, 64KB of built-in FLASH and 6KB of SRAM, and supports multiple low-power modes. The wireless communication module uses an NRF24L01 chip, connected to the microcontroller via an SPI interface. LED indicators are used to show the wireless module's detection error or operating status. The GPIO interface is used to connect external devices and detect input signals. The ADC module is integrated inside the microcontroller, with 12-bit precision and 16 input channels, used to acquire current or voltage signals. The current interruption comparator uses a VC2 comparator to detect current interruption events and generate a falling edge interrupt. The capacitor charging circuit charges the current interruption detection capacitor. The power management unit is controlled by the microcontroller to switch between sleep and wake-up modes.

[0045] Example 2

[0046] like Figure 1-9 As shown, this embodiment discloses a low-power current detection system and method for electrically operated drop-out fuses. The low-power workflow of this invention is as follows:

[0047] Step 1: After the system is powered on and reset, perform hardware initialization; initialize the clock, GPIO, SPI, ADC and NRF24L01 wireless communication module.

[0048] Step 2: Check if the wireless communication module is working properly; if the check fails, control the LED to flash (error indicator) and continue to indicate; if the check succeeds, control the LED to flash 7 times quickly (success indicator), and then enter the main loop; the status indicator unit uses RGB tri-color LEDs, and its control logic is as follows:

[0049] Green flashing: System is operating normally and there is line current; Red flashing: Wireless communication module malfunction;

[0050] Blue flashing 7 times: System power-on self-test successful; Red and blue flashing alternately: Manual test mode; Red and green flashing alternately: Battery low voltage, insufficient power.

[0051] Step 3: In the main loop, check the GPIO initialization flag; if GPIO_INIT_FLAG is 0 (not initialized), then reinitialize GPIO and delay for 50ms, repeat this process until initialization is complete.

[0052] Step 4: Check the interruption flag; if the interruption flag (IO_FLAG) is valid, perform the following operations:

[0053] Disable the current interrupt comparator interrupt; clear the current interrupt flag; enable current interrupt delay detection; initialize the timer and perform current sampling.

[0054] Step 5: Determine the power-on current flag. If the power-on current flag is valid, disable the interruption of the current cutoff comparator, clear the power-on current flag, send a wake-up packet, and send the first type of data through the wireless communication module.

[0055] Step 6: Determine the alarm flag; if the alarm flag (DROP_FLAG) is valid, then: issue an alarm; clear DROP_FLAG; send a wake-up packet; send alarm data (type 0) through the wireless communication module.

[0056] Step 7: Check the capacitor full charge wake-up flag; if the capacitor full charge wake-up flag (C_WAKE_FLAG) is valid, then:

[0057] Disable VC2 interrupt; charge the current interrupt detection capacitor; set the corresponding GPIO pin to working mode (IO_Pin_In_Work_Mode); clear C_WAKE_FLAG; send wake-up packet and current data.

[0058] Step 8: Check the manual wake-up flag; if the manual wake-up flag (M_WAKE_FLAG) is valid, then:

[0059] Clear the flag; enter manual test mode and execute the TEST function.

[0060] Step 9: Detect the input level of the capacitor full charge wake-up pin; if the C_WAKE pin is low, then: set the capacitor full charge wake-up flag (C_WAKE_FLAG=1); clear the data flag (DATA_FLAG).

[0061] Step 10: Check the timer flag; if IO_TIMER_FLAG == 0 (timer invalid), prepare to enter sleep mode: turn off the battery ADC switch; clear all flag bits; set NRF24L01 to sleep mode; perform deinitialization operations on SPI and GPIO, and configure GPIO to sleep state;

[0062] Enable the current cutoff comparator; execute DeepSleep to sleep and wait for a wake-up source (VC2 interrupt, U2 falling edge, manual button press); if IO_TIMER_FLAG != 0, return to the main loop to continue execution.

[0063] Example 3

[0064] like Figure 11-15 As shown in the figure, this embodiment discloses a low-power current detection system and method for an electric drop-out fuse, which includes a main control unit, a power management unit, a battery voltage monitoring unit, a non-contact status detection unit, a debugging interface unit, and a status indication unit.

[0065] like Figure 11 As shown, the main control unit, or microcontroller, is a 32-bit ARM Cortex-M0+ microcontroller (U1) manufactured by Wuhan Xinyuan Semiconductor Co., Ltd., model CW32L011K8U6. This microcontroller operates from 1.8V to 3.6V and integrates 64KB FLASH, 6KB SRAM, a 12-bit 1M SPS ADC, multiple low-power UARTs, and an SPI interface. Its power supply pins VDD and VCC are connected, and VSS is connected to GND; the reset pin RST is connected to an external reset circuit; the ADC input pin PA0 is connected to the output BAT_ADC of the battery voltage monitoring unit; the general-purpose input / output pin PB0 is connected to the output of the non-contact status detection unit; and the SWCLK and SWDIO pins are connected to the debug interface unit.

[0066] like Figure 12 As shown, the power management unit includes a first low-dropout linear regulator U6 and a second low-dropout linear regulator U7. U6 is a ME6214C33 model, with its input VIN connected to the positive terminal VBAT of an external battery, and its output OUT providing a 3.3V system power supply VCC. The enable terminal CE is connected to VIN, and the ground terminal VSS is connected to GND. U7 is a ME6214C18 model, with its input VIN connected to VCC, and its output OUT providing a 1.8V power supply 1V8, which is used for the microcontroller core or low-voltage peripherals.

[0067] The input and output terminals of U6 and U7 are connected in parallel with filter capacitors, with the input capacitor C22 being 47μF and the output capacitor C4 being 10μF. In addition, the global decoupling capacitor array includes multiple 100nF ceramic capacitors (C5, C11, C12, C15, C16, C24) and multiple 100μF electrolytic capacitors (C18, C19, C20, C21), which are respectively arranged between VCC and the 1V8 power network and ground.

[0068] like Figure 14As shown, the battery voltage monitoring unit includes a voltage divider network and a voltage detection chip U8. The voltage divider network consists of a first resistor R16 (1.27MΩ), a second resistor R19 (1.27MΩ), a third resistor R17 (100kΩ), a fourth resistor R18 (100kΩ), and two N-channel MOSFETs Q5A and Q5B. The positive terminal VBAT of the battery is grounded sequentially through R16, Q5A, and R17, and simultaneously through R19, Q5B, and R18. The gates of Q5A and Q5B are connected to the GPIO pin SW of the microcontroller U1, and their sources are grounded. The drain connection points of the two MOSFETs output the BAT_ADC signal respectively. The voltage detection chip U8 is a CN301. Its positive input IN+ is connected to VBAT through the fifth resistor R23 (2MΩ), its negative input IN- is grounded through the sixth resistor R24 ​​(2MΩ), and its output OUT is connected to point B (i.e., the other ADC input of the microcontroller) through the seventh resistor R25 (1.27MΩ).

[0069] The power supply terminal VCC of U8 is connected to VCC, and the ground terminal GND is grounded. A filter capacitor C13 (100nF) is connected in parallel to its power supply pin. The working process of this unit is as follows: the microcontroller controls the conduction and cutoff of Q5A and Q5B through the SW pin to select different voltage divider paths; the BAT_ADC signal is sampled by the ADC of U1 to obtain the battery voltage value; at the same time, CN301 amplifies the differential voltage between VBAT and ground and outputs it to the microcontroller to realize redundant monitoring of the battery status.

[0070] like Figure 12 As shown, the non-contact status detection unit includes three omnipolar Hall switch chips. In this embodiment, chips U3, U9, and U10 of model DH629 are used. The power supply terminals VCC of chips U3, U9, and U10 are connected in parallel and then connected to VCC. The ground terminals GND are connected in parallel and then grounded. The output terminal OUT is connected to the M_WAKE pin of microcontroller U1. A decoupling capacitor C15 (100nF) is connected in parallel to the power supply pin of U3, a decoupling capacitor C10 (100nF) is connected in parallel to the power supply pin of U9, and a decoupling capacitor C17 (100nF) is connected in parallel to the power supply pin of U10.

[0071] With this wired-AND or OR logic connection, when any Hall switch detects a change in the external magnetic field (i.e., the fuse trips or drops), its output changes from high to low (or vice versa), causing a level change on the M_WAKE pin and immediately triggering the external interrupt wake-up of U1. This solution replaces the original mercury switch, with a response time of less than 5ms and no acceleration direction limitation. At the same time, the three Hall switches can be arranged in different mechanical positions of the fuse to achieve redundant detection or multi-point drop sensing.

[0072] like Figure 15As shown, the debugging interface unit is a standard 4-pin SWD interface J3. Pin 1 is connected to VCC, pin 2 is connected to SWCLK, pin 3 is connected to GND, and pin 4 is connected to SWDIO. After J4 is connected to an external emulator, the microcontroller U1 can be downloaded online and debugged in real time.

[0073] like Figure 12 As shown, the status indicator unit includes an RGB tri-color LED and its current-limiting resistor. The anode of the red LED is connected to the microcontroller's GPIO (e.g., PA0) via the eighth resistor R31 (1kΩ), the anode of the green LED is connected to another GPIO (e.g., PA1) via the ninth resistor R32 (1kΩ), and the anode of the blue LED is connected to the third GPIO (e.g., PA2) via the tenth resistor R33 (1kΩ). The cathodes of all LEDs are grounded together. The microcontroller outputs PWM signals with different duty cycles to make the RGB LEDs mix and display different colors to indicate the system's operating status, battery level, or communication status.

[0074] like Figure 12 As shown, the reset circuit consists of an eleventh resistor R8 (10kΩ) and an eleventh capacitor C4 (10μF), forming a classic RC reset circuit. One end of R8 is connected to VCC, and the other end is connected to both the microcontroller's reset pin RST and the positive terminal of C4. The negative terminal of C4 is grounded. When powered on, C4 charges, causing the RST pin to remain at a low level briefly before going high, thus achieving a system power-on reset.

[0075] This embodiment achieves long-term autonomous operation of battery-powered equipment by employing an ultra-low-power MCU, a low-power LDO, and a low-power Hall switch; at the same time, it improves the accuracy and reliability of battery detection through redundant voltage monitoring and differential amplification circuits; and the omnipolar Hall switch simplifies the installation polarity requirements and reduces production and maintenance costs.

[0076] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0077] Based on the above circuit, the working process of this embodiment in the electrically operated drop-out fuse is as follows:

[0078] Low current energy extraction and detection: When the line current is ≥0.3A, the transformer output is rectified and quickly establishes voltage through C13. U8 starts and charges C3. Even if the current is only 0.3A, the system can work stably, realizing the expansion of the low current detection range.

[0079] Fast interruption response: Once the line current drops sharply below the interruption threshold, the DROP signal instantly triggers the MCU interrupt. The MCU is woken up within <100μs, immediately records the event and sends an alarm, without waiting for C3 to charge to V_H. Compared with traditional solutions, the response time is reduced by more than 90%.

[0080] Solid-state electronic wake-up: All wake-up sources (current cut-off, capacitor full charge, manual button press) are implemented through comparators or GPIO interrupts. There is no mercury switch, the average power consumption of the system is less than 2μA, and it can operate without maintenance for a long time.

[0081] Single-phase independent monitoring and communication: Each phase data collector works independently and reports information such as phase current and alarms to the concentrator through the MODBUS protocol, realizing refined phase-by-phase management.

[0082] Adaptive charging cycle: Under normal current conditions, the C3 voltage cycles between V_H and V_L. The MCU periodically wakes up and sends current data. The higher the line current, the higher the cycle frequency, achieving energy self-balancing. The entire system does not require an external power supply or mercury switch. It supports 0.3A low current start-up, has a rapid current interruption response, and single-phase monitoring data can be read remotely via MODBUS. It is particularly suitable for the intelligent transformation of fuses in rural power grids and distribution networks.

[0083] The foregoing has shown and described the basic principles and main features of the present invention and its advantages. It will be apparent to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, the embodiments should be regarded as exemplary and non-limiting in all respects. The scope of the present invention is defined by the appended claims rather than the foregoing description. Therefore, it is intended that all changes falling within the meaning and scope of the equivalents of the claims be included within the present invention, and no reference numerals in the claims should be regarded as limiting the scope of the claims.

[0084] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A low-power current detection system for an electrically operated drop-out fuse, characterized in that, include: microcontroller; Current transformers are used to sense line current; A rectifier bridge, connected to the secondary side of the current transformer, is used to convert alternating current into pulsating direct current. A small-capacity capacitor with a capacitance value ≤10μF is connected to the output terminal of the rectifier bridge to quickly establish voltage under line current as low as 0.3A. The first comparator is connected to the output terminal of the small-capacity capacitor and is used to generate a start signal when the voltage of the small-capacity capacitor exceeds the reference voltage. A farad capacitor, connected to the output of the first comparator via a PMOS transistor, is used to store electrical energy and supply power to the system. A wireless communication module, connected to the microcontroller, is used for data transmission and reception; LED indicator lights are used to indicate whether the wireless module has detected an error or is in operation. GPIO interface, used to connect external devices and detect input signals; The ADC module, either integrated inside the microcontroller or set up independently externally, is used to acquire current or voltage signals; A current interrupt comparator is used to detect current interruption events and generate a falling edge interrupt; it is directly connected to the external interrupt pin of the microcontroller. A capacitor charging circuit is used to charge the current-breaking detection capacitor. The power management unit, controlled by the microcontroller, is used to switch between sleep and wake-up modes; The output signal of the current interruption comparator is independent of the charging state of the farad capacitor and can instantly wake up the microcontroller when the line current drops sharply below the threshold.

2. The low-power current detection system for an electrically operated drop-out fuse according to claim 1, characterized in that: The wireless communication module is an NRF24L01 chip, and the microcontroller communicates with it via an SPI interface.

3. The low-power current detection system for an electrically operated drop-out fuse according to claim 1, characterized in that: The interrupt comparator is a VC2 comparator, whose falling edge output is directly connected to the external interrupt pin of the microcontroller for instantaneously waking the microcontroller from sleep mode.

4. The low-power current detection system for an electrically operated drop-out fuse according to claim 1, characterized in that: The current transformer, under line current as low as 0.3A, activates the PMOS transistor through the small-capacity capacitor and the first comparator to charge the farad capacitor, enabling the system to obtain operating power from the weak line current.

5. A method for using a low-power current detection system and method for an electrically operated drop-out fuse, characterized in that: It also includes the following steps: Step 1: After the system powers on and resets, hardware initialization is performed, including the initialization of the clock, GPIO, SPI, ADC and wireless communication modules; Step 2: Check if the wireless communication module is working properly. If not, output an error indication; if yes, enter the main loop. Step 3: In the main loop, check the GPIO initialization flag. If the flag indicates that the GPIO is not initialized, reinitialize the GPIO and delay until the GPIO initialization is complete. Step 4: Determine the current interruption flag. If the current interruption flag is valid, disable the current interruption comparator interrupt, clear the current interruption flag, enable current interruption delay detection, initialize the timer, and perform current sampling. Step 5: Determine the power-on current flag. If the power-on current flag is valid, disable the interruption of the current cutoff comparator, clear the power-on current flag, send a wake-up packet, and send the first type of data through the wireless communication module. Step 6: Determine the alarm flag. If the alarm flag is valid, clear the alarm flag and send the second type of data through the wireless communication module. Step 7: Determine the capacitor full charge wake-up flag. If the capacitor full charge wake-up flag is valid, then disable the current cut-off comparator interrupt, charge the current cut-off detection capacitor, set the corresponding GPIO pin to working mode, and send a wake-up packet and current data. Step 8: Determine the manual wake-up flag. If the manual wake-up flag is valid, clear the flag and execute the manual test function. Step 9: Detect the input level of the capacitor full charge wake-up pin. If the pin is low, set the capacitor full charge wake-up flag and clear the data flag. Step 10: Determine the timer flag. If the timer flag is invalid, disable battery ADC sampling, clear all flag bits, perform deinitialization operations on the wireless communication module, SPI and GPIO, configure GPIO to sleep mode, enable the current cut-off comparator, and then enter sleep mode and wait to be woken up. If the timer flag is valid, return to the main loop to continue execution.

6. The low-power current detection system and method for an electrically operated drop-out fuse according to claim 5, characterized in that: In the fourth step, the interruption delay detection is achieved by initializing a 200ms timer and calling the sampling function in the timer interrupt service function. If the sampling value is lower than the interruption threshold three times in a row within 200ms, the interruption event is confirmed.

7. The low-power current detection system and method for an electrically operated drop-out fuse according to claim 5, characterized in that: In the fifth step, the first type of data is the data packet sent when the system detects current upon initial power-up.

8. The low-power current detection system and method for an electrically operated drop-out fuse according to claim 5, characterized in that: In the sixth step, the second type of data is the data packet sent when the system detects a disconnection alarm event.

9. The low-power current detection system and method for an electrically operated drop-out fuse according to claim 5, characterized in that: In the seventh step, after the current interruption detection capacitor has finished charging, the wake-up packet sent has the same format as the wake-up packet in step S5, and the current data sent includes real-time sampled values.

10. The low-power current detection system and method for an electrically operated drop-out fuse according to claim 5, characterized in that: In the tenth step, the sleep wake-up source includes at least: falling edge interrupt of the interrupt comparator and manual key input.

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