Circuit breaker and method for detecting its operating state

Abstract

Disclosed are a circuit breaker and a working state detection method thereof. The circuit breaker comprises a self-checking control module, an induction module, a leakage detection module and a protection module. The self-checking control module synchronously generates an analog leakage signal according to an alternating current signal and outputs the analog leakage signal to a zero line of the alternating current circuit. The induction module is coupled with a live line of the alternating current circuit and generates a trigger signal according to a change in magnetic flux at the coupling position. The leakage detection module is connected with the induction module to obtain the trigger signal and generates a conduction signal according to the trigger signal. The protection module is connected with the live line of the alternating current circuit, the leakage detection module and the self-checking control module, respectively, and is used for generating a first detection signal according to the alternating current signal and generating a second detection signal according to the conduction signal, and outputting the first detection signal and the second detection signal to the self-checking control module. The self-checking control module judges the working state of the circuit breaker according to the received first detection signal and second detection signal, so as to quickly detect whether the circuit breaker can perform leakage protection. The whole process is automatically completed after power-on, and is efficient and simple.

Description

Technical Field

[0001] This article relates to the field of power electronics, specifically to circuit breakers and their operational status detection methods. Background Technology

[0002] Appliance residual current circuit breakers (ALCIs) have residual current protection functions, which can effectively prevent electric shock and fire accidents, and are therefore widely used in household appliances. However, appliance residual current circuit breakers themselves may also malfunction, such as the end of the lifespan of internal components, leading to the loss of residual current protection functions. In such cases, continued use of the device may result in electric shock or fire accidents.

[0003] Therefore, existing ALCI systems require manual testing to ensure they function correctly. Figure 1 A schematic circuit diagram of a circuit breaker according to the prior art is shown, such as Figure 1 As shown, the AC circuit is connected between the power supply and the load. An induction coil N1 is coupled to the live and neutral wires of the AC circuit. The leads of coil N1 are connected to the leakage current protection module 10. The leakage current protection module 10 is connected to the control terminal of the thyristor SQ. The anode of the thyristor SQ is connected to the solenoid L, and the cathode is grounded. The solenoid L is connected to the main line of the AC circuit, controlling the opening and closing of switches S1 and S2. The rectifier bridge BD supplies power to the leakage current protection module. A manual detection button BT and a resistor R connected in series with it are also connected to the main line. When a circuit fault occurs, such as a factor affecting the main line current at node Q, causing the vector sum of the currents between the live and neutral wires of the AC circuit to be non-zero, the magnetic flux in the induction coil N1 changes, inducing an induced electromotive force, which is sent to the leakage current protection module 10. The leakage current protection module 10 sends a conduction signal to the control terminal of the thyristor SQ, connecting the thyristor SQ and the solenoid L. The solenoid L then opens switches S1 and S2, cutting off the AC circuit and providing protection. The manual test switch BT can be used to manually test whether a circuit breaker is working properly.

[0004] However, in practice, manual testing is often neglected or forgotten, which may lead to potential failures of some key components in the ALCI system, potentially causing electric shock accidents. Moreover, manual testing is often inconvenient and needs improvement. Summary of the Invention

[0005] In view of the above, the purpose of this invention is to provide a circuit breaker suitable for AC circuits and a detection method thereof, providing a self-test control module that sends a simulated leakage current signal and detects the voltage of the thyristor anode, thereby determining whether the circuit can work normally and realizing automatic circuit detection.

[0006] According to a first aspect of the present invention, a circuit breaker for an AC circuit is provided, comprising:

[0007] The self-test control module synchronously generates a simulated leakage current signal based on the AC signal and outputs it to the neutral wire of the AC circuit.

[0008] The sensing module is coupled to the main line of the AC circuit and generates a trigger signal based on the change in magnetic flux at the coupling point;

[0009] A leakage current detection module is connected to the sensing module to obtain the trigger signal and to generate a conduction signal based on the trigger signal; and

[0010] The protection module is connected to the live wire of the AC circuit, the leakage current detection module, and the self-test control module, respectively. It generates a first detection signal based on the AC signal and a second detection signal based on the conduction signal, and outputs both the first and second detection signals to the self-test control module.

[0011] The self-test control module determines the operating status of the circuit breaker based on the received first detection signal and second detection signal.

[0012] Preferably, the protection module includes:

[0013] A solenoid, connected between the live wire and the silicon controlled rectifier (SCR) of the AC circuit, is used to disconnect or connect the AC circuit; and

[0014] A thyristor is connected between the solenoid and ground, and the control electrode of the thyristor is connected to the leakage current detection module to receive the conduction signal.

[0015] Preferably, during the positive half-cycle of the AC power supply, when the change in the current vector sum on the main line of the AC circuit causes a change in magnetic flux at the coupling point, the sensing module generates the trigger signal and outputs it to the leakage current detection module. The leakage current detection module receives the trigger signal and outputs a conduction signal to the control electrode of the thyristor. The thyristor conducts according to the conduction signal and disconnects the AC circuit through the solenoid.

[0016] Preferably, the protection module further includes:

[0017] A first diode is connected in series between the thyristor and the solenoid, with the cathode of the first diode connected to the anode of the thyristor. The first diode is used to block the connection between the thyristor and the solenoid during the negative half-cycle of the AC power supply.

[0018] Preferably, the circuit breaker begins fault detection for at least one AC cycle after the AC circuit is powered on for a preset time, and performs fault detection once at regular intervals. The fault detection includes continuous connectivity detection and simulated leakage detection.

[0019] Preferably, the connectivity detection of the protection module is performed during the positive half-cycle of the AC power supply. The AC signal passes through the solenoid to the anode of the thyristor, causing the first detection signal to be generated at the first node between the thyristor and the first diode.

[0020] The self-test control module compares the voltage value of the first detection signal with the first threshold voltage and determines whether the circuit breaker has malfunctioned.

[0021] Preferably, during the positive half-cycle of the AC power supply, when the voltage value of the first detection signal is less than the first threshold voltage, the circuit breaker performs the connectivity test for multiple AC cycles. When the voltage value of the first detection signal remains less than the first threshold voltage during the connectivity test for multiple AC cycles, the self-test control module generates an alarm signal.

[0022] Preferably, during the positive half-cycle of the AC power supply, when the voltage value of the first detection signal is greater than or equal to the first threshold voltage, the simulated leakage current detection is performed during the negative half-cycle of the AC power supply.

[0023] Preferably, the simulated leakage current detection is performed during the negative half-cycle of the AC power supply. The self-test control module sends the generated simulated leakage current signal to the sensing module. The leakage current detection module receives the trigger signal generated by the sensing module and outputs a conduction signal to the thyristor to turn on the thyristor, so that a second detection signal is generated at the first node.

[0024] Preferably, during the negative half-cycle of the AC power supply, when the self-test control module receives the second detection signal, the fault detection ends; when the self-test control module does not receive the second detection signal, the circuit breaker performs the simulated leakage current detection for multiple AC cycles. If the self-test control module does not receive the second detection signal within the preset multiple AC cycles, the self-test control module generates an alarm signal.

[0025] Preferably, the first detection signal is high level and the second detection signal is low level.

[0026] Preferably, the circuit breaker further includes:

[0027] The rectifier bridge is connected to the main line of the AC circuit and is used to provide power to the self-test control module and the leakage current detection module.

[0028] A protective resistor is connected between the live wire and the neutral wire in the AC circuit.

[0029] A switch is used to disconnect or connect the AC circuit under the control of the solenoid.

[0030] Preferably, the circuit breaker further includes a manual self-test module connected between the live wire and the neutral wire of the AC circuit for manually testing the operating status of the circuit breaker.

[0031] Preferably, the manual self-test module includes an eighth resistor and a first self-test button connected in series.

[0032] Preferably, the leakage current detection module includes:

[0033] A leakage current detection chip, the leakage current detection chip including multiple pins, for receiving the trigger signal and outputting the conduction signal;

[0034] The first resistor is connected to the sixth pin of the leakage current detection chip;

[0035] The second resistor is connected between the first pin of the leakage current detection chip and the sensing module.

[0036] A first capacitor is connected between the fourth and fifth pins of the leakage current detection chip; and

[0037] The second capacitor is connected between the fifth and sixth pins of the leakage current detection chip.

[0038] Preferably, the sensing module includes an induction coil coupled to the trunk of the AC circuit, and a third resistor connected between one end of the induction coil and the second resistor. The third resistor is also connected to the second pin of the leakage current detection chip, and the other end of the induction coil is connected to the third pin of the leakage current detection chip.

[0039] Preferably, the self-test control module includes a self-test control chip, and the self-test control chip includes multiple pins, wherein...

[0040] The fault pin is used to output the analog leakage signal;

[0041] The detection pin is used to receive the first detection signal and the second detection signal;

[0042] The alarm pin is used to output the alarm signal;

[0043] The clock pin is used to receive AC signals from the AC circuit and generate a clock signal to start the faulty pin.

[0044] The power supply pin is used to receive voltage signals from the rectifier bridge to power the self-test control chip.

[0045] Preferably, the self-test control module further includes:

[0046] A fourth resistor is connected between the detection pin and the first node;

[0047] The fifth resistor is connected between the power supply pin and the rectifier bridge;

[0048] The sixth resistor is connected between the clock pin and the live wire of the AC circuit;

[0049] The seventh resistor is connected between the fault pin and the neutral wire of the AC circuit;

[0050] A third capacitor is connected between the power supply pin and ground; and

[0051] The second diode is connected in parallel across the fourth resistor.

[0052] Preferably, the second diode of the self-test control module is cut off during the positive half-cycle of the AC power supply, and during the negative half-cycle of the AC power supply during the simulated leakage current detection, the detection pin detects the second detection signal of the first node.

[0053] Preferably, after the detection pin of the self-test control module receives the second detection signal, it stops sending the simulated leakage current signal of the fault pin, and the simulated leakage current detection is completed. According to a second aspect of the present invention, a method for detecting the operating status of a circuit breaker is provided, comprising:

[0054] Perform connectivity testing and generate a first detection signal based on the AC signal;

[0055] Simulated leakage current detection is performed by generating a simulated leakage current signal during the negative half-cycle of the AC signal, which causes a change in magnetic flux.

[0056] Obtain a trigger signal generated based on the change in magnetic flux, and generate a conduction signal based on the trigger signal;

[0057] A second detection signal is generated based on the conduction signal; and

[0058] The operating status of the circuit breaker is determined based on the received first detection signal and second detection signal.

[0059] Preferably, the detection method further includes: starting fault detection for at least one AC cycle after a preset power-on time, wherein the fault detection includes the continuous connectivity detection and the simulated leakage current detection.

[0060] Preferably, the connectivity detection, and the generation of a first detection signal based on the AC signal, includes:

[0061] During the positive half-cycle of the AC power supply, the AC signal passes through the first node to generate the first detection signal;

[0062] The voltage value of the first detection signal is compared with the first threshold voltage;

[0063] When the voltage value of the first detection signal is greater than or equal to the first threshold voltage, the simulated leakage current detection is performed;

[0064] When the voltage value of the first detection signal is less than the first threshold voltage, a connectivity test is performed for multiple AC cycles. If the voltage value of the first detection signal is still less than the first threshold voltage during the multiple AC cycles of connectivity test, an alarm signal is generated.

[0065] Preferably, generating a second detection signal based on the conduction signal, and determining the operating state of the circuit breaker based on the received second detection signal includes:

[0066] During the negative half-cycle of the AC power supply, the trigger signal is generated based on the simulated leakage current signal;

[0067] A conduction signal is generated based on the trigger signal;

[0068] The output of the conduction signal causes a second detection signal to be generated at the first node;

[0069] The fault detection ends when the second detection signal is received.

[0070] If the second detection signal is not received, the simulated leakage current detection is performed for one or more AC cycles. If the second detection signal is not received within the preset multiple AC cycles, an alarm signal is generated.

[0071] Preferably, after receiving the second detection signal, the simulated leakage signal stops being sent, and the simulated leakage detection is completed.

[0072] Preferably, the detection method further includes:

[0073] During the positive half-cycle of the AC power supply, when the change in current on the main line of the AC circuit generates a change in magnetic flux, the trigger signal is output.

[0074] Receive the trigger signal and output a conduction signal;

[0075] The AC circuit is disconnected according to the conduction signal.

[0076] Preferably, the first detection signal is high level and the second detection signal is low level.

[0077] This circuit breaker uses a protection module to generate a first detection signal based on the AC signal of the AC circuit, and a simulated leakage current signal provided by a self-test control module to activate the leakage current detection module, activate the protection module, and jointly determine the working status of the circuit breaker based on the second detection signal generated by the protection module. It can detect whether the circuit breaker can perform normal leakage current protection. The whole process is completed automatically after power-on, without manual intervention, which improves efficiency and protects the personal safety of users.

[0078] After a preset power-on time, the circuit breaker begins fault detection for at least one AC cycle. During fault detection, the connectivity of the protection module is tested separately during the positive half-cycle of the AC power supply to ensure that the protection circuit can alarm in time when a fault occurs. During the negative half-cycle of the AC power supply, a simulated leakage current test is performed separately to check whether the leakage current detection module and the protection module can play a leakage current protection role when a leakage current occurs in the circuit. The two tests are performed alternately during the positive and negative half-cycles of the AC power supply. When the circuit breaker malfunctions, an alarm signal is generated to prompt the user to replace the circuit breaker and ensure safety in a timely manner.

[0079] The simulated leakage signal generated by the self-test control module can enable the circuit breaker to perform protective actions when a leakage occurs in the circuit, but it will not affect the normal protection function of the circuit breaker when a real circuit fault occurs. When a leakage occurs in the circuit, the power supply can be cut off in time through the protection module.

[0080] This circuit breaker determines whether it can work properly by detecting the voltage of the thyristor anode, thus protecting the circuit. The method is simple and efficient, the test results are intuitive, and the judgment can be made quickly. Attached Figure Description

[0081] The above and other objects, features and advantages of the present invention will become clearer from the following description of embodiments of the invention with reference to the accompanying drawings.

[0082] Figure 1 A schematic circuit diagram of a circuit breaker according to the prior art is shown.

[0083] Figure 2 A schematic block diagram of a circuit breaker according to an embodiment of the present invention is shown.

[0084] Figure 3a and Figure 3bA schematic block diagram and a schematic circuit diagram of a circuit breaker according to yet another embodiment of the present invention are shown respectively.

[0085] Figure 4 Show Figure 3a and Figure 3b A detailed schematic circuit diagram of the circuit breaker.

[0086] Figure 5 The diagram shows the operating waveform of the circuit breaker when it is functioning normally during simulated leakage current detection according to an embodiment of the present invention.

[0087] Figure 6 The diagram shows the operating waveform of the circuit breaker when a fault occurs during simulated leakage current detection according to an embodiment of the present invention.

[0088] Figure 7a and Figure 7b The diagrams show the operating waveforms of the circuit breaker according to an embodiment of the present invention when the thyristor is short-circuited and the solenoid is open-circuited during connectivity testing. Detailed Implementation

[0089] Various embodiments of the invention will now be described in more detail with reference to the accompanying drawings. In the various drawings, the same elements are indicated by the same or similar reference numerals. For clarity, the various parts in the drawings are not drawn to scale.

[0090] Figure 2 A schematic block diagram of a circuit breaker according to an embodiment of the present invention is shown. The circuit breaker includes a sensing module 101, a self-test control module 102, a leakage current detection module 103, and a protection module 104. Figure 2 As shown, the live wire L and neutral wire N in the main line of the AC circuit are connected to the power supply terminal and the load terminal, and the AC circuit is switched on and off by switches S1 and S2.

[0091] The self-test control module 102 is connected to the live wire L to obtain an AC signal, and generates an analog leakage signal Vleak synchronously based on the AC signal, and outputs it to node Q2 of the neutral wire N of the AC circuit, causing a change in magnetic flux at the coupling point between the induction module 101 and the main line of the AC circuit.

[0092] The sensing module 101 is coupled to the main line of the AC circuit and is used to convert the change in magnetic flux at the coupling point into a trigger signal Vtri and output it to the leakage current detection module 103. When the vector sum of the currents on the main line of the AC circuit is not zero, it will cause a change in magnetic flux, and the sensing module 101 will generate a trigger signal Vtri according to the change in magnetic flux.

[0093] The leakage current detection module 103 is connected to the sensing module 101 to obtain the trigger signal Vtri generated by the sensing module 101 according to the change of magnetic flux, and to generate a conduction signal Vcon according to the trigger signal Vtri, which is then output to the protection module 104.

[0094] The protection module 104 is connected between the live wire of the AC circuit and the leakage current detection module 103. It is used to generate a first detection signal VS1 based on the AC signal from the AC circuit and a second detection signal VS2 based on the conduction signal Vcon from the leakage current detection module 103. The protection module 104 is electrically connected to the self-test control module 102. The self-test control module 102 determines the operating status of the circuit breaker based on the received first detection signal VS1 and second detection signal VS2.

[0095] The circuit breaker begins fault detection for at least one AC cycle after a preset time following power-on of the AC circuit. Fault detection includes continuous connectivity detection and simulated leakage current detection during the positive and negative half-cycles of the AC power supply. Preferably, during the positive half-cycle of the AC power supply, the protection module 104 generates a first detection signal VS1 based on the AC signal from the AC circuit. The self-test control module 102 receives the first detection signal VS1 and determines whether the protection module 104 is functioning normally. During the negative half-cycle of the AC power supply, the self-test control module 102 outputs a simulated leakage current signal Vleak to the sensing module 101. The sensing module 101 generates a trigger signal Vtri based on the change in magnetic flux caused by the simulated leakage current signal Vleak. The leakage current detection module 103 generates a conduction signal Vcon based on the trigger signal Vtri and outputs it to the protection module 104. The protection module 104 generates a second detection signal VS2 based on the conduction signal Vcon from the leakage current detection module 103. The self-test control module 102 receives the second detection signal VS2 and determines whether the leakage current detection module 103 and the protection module 104 are functioning normally.

[0096] Preferably, when the self-test control module 102 is not working, if the current on the live wire or neutral wire at node Q2 changes, causing a change in the current vector sum on the main line of the AC circuit, it will also cause a change in the magnetic flux in the sensing module 101. The sensing module 101 generates a trigger signal Vtri and outputs it to the leakage current detection module 103. The leakage current detection module 103 receives the trigger signal Vtri and outputs a conduction signal Vcon to the protection module 104. The protection module 104 receives the conduction signal Vcon and accordingly turns off switches S1 and S2 to disconnect the AC circuit.

[0097] Figure 3a and Figure 3b A schematic block diagram and a schematic circuit diagram of a circuit breaker according to another embodiment of the present invention are shown respectively. The circuit breaker is... Figure 2 The optimization scheme, and Figure 2 The same embodiment is used. The circuit breaker includes a sensing module 110, a self-test control module 120, a leakage current detection module 130, and a protection module 140. In addition, it also includes a rectifier bridge 150 and a manual self-test module 160.

[0098] like Figure 3a and Figure 3b As shown, the live wire L and neutral wire N in the main line of the AC circuit are connected to the power supply terminal and the load terminal, and the on / off state of the main line of the AC circuit is controlled by switches S1 and S2. The self-test control module 120 is connected to the live wire L to obtain the AC signal. The self-test control module 120 synchronously generates an analog leakage current signal Vleak based on the AC signal and outputs it to the sensing module 110. The sensing module 110 is coupled to the main line of the AC circuit and is used to generate a trigger signal Vtri based on the change in magnetic flux. The leakage current detection module 130 is connected to the sensing module 110 to obtain the trigger signal Vtri and generate a conduction signal Vcon based on the trigger signal Vtri. The protection module 140 is connected between the live wire L and the leakage current detection module 130 and is used to generate a first detection signal VS1 based on the AC signal of the AC circuit and a second detection signal VS2 based on the conduction signal Vcon. The self-test control module 120 determines the operating state of the circuit breaker based on the received first detection signal VS1 and second detection signal VS2.

[0099] The input terminal of rectifier bridge 150 is connected to the main line of the AC circuit to provide power to self-test control module 120 and leakage current detection module 130. One end of the input terminal of rectifier bridge 150 is connected to the neutral line N, and the other end is connected to the live line L. One of the two output terminals of rectifier bridge 150 is grounded, and the other output terminal supplies power to self-test control module 120 and leakage current detection module 130 respectively, providing voltage signals.

[0100] The manual self-test module 160 is connected between the live wire L and the neutral wire N of the AC circuit main line. Its first end is connected to the live wire L in the AC circuit main line, and its second end is connected to the neutral wire N in the AC circuit main line. It is used to manually test the operating status of the circuit breaker. For example, the manual self-test module 160 includes a resistor R8 connected in series and a self-test button B1, which allows manual testing of the circuit breaker's operating status.

[0101] The circuit breaker in this embodiment further includes a protective resistor RV, connected between the live wire L and the neutral wire N, for protection. Switches S1 and S2 are connected in series with the live wire L and the neutral wire N, respectively, to disconnect or connect the AC circuit.

[0102] Furthermore, the sensing module 110 includes an induction coil SC1 coupled to the main line of the AC circuit, and a resistor R3 connected between one end of the induction coil SC1 and the leakage current detection module 130. The other end of the induction coil SC1 is also connected to the leakage current detection module 130. The induction coil SC1 can sense the current vector sum on the main line of the AC circuit. For example, when a factor affecting the current on the main line of the AC circuit occurs at node Q2, causing the current vector sum between the live wire L and the neutral wire N of the AC circuit to be non-zero, a change in magnetic flux will be generated in the coil SC1. The sensing module 110 generates a trigger signal Vtri based on the change in magnetic flux, and outputs it to the leakage current detection module 130 after passing through the resistor R3.

[0103] Protection module 140 includes a solenoid SQL and a silicon controlled rectifier (SCR) SQ1. The solenoid SQL is connected between the live wire L of the AC circuit and the SCR SQ1, used to turn off or on the AC circuit by controlling the opening or closing of switches S1 and S2. The SCR SQ1 is connected between the solenoid SQL and ground. The anode of the SCR SQ1 is connected to one end of the solenoid SQL, and the other end of the solenoid SQL is connected to the live wire L. The cathode of the SCR SQ1 is grounded, and its control electrode is connected to the leakage current detection module 130 to receive the conduction signal Vcon for conduction. Protection module 140 also includes a diode D1, connected in series between the SCR SQ1 and the solenoid SQL. The cathode of the diode D1 is connected to the anode of the SCR SQ1. The diode D1 is used to block the connection between the SCR SQ1 and the solenoid SQL during the negative half-cycle of the AC power supply. A point is selected between the anode of the thyristor SQ1 and the cathode of the diode D1 as node Q1. The self-test control module 120 detects the first detection signal VS1 and the second detection signal VS2 from node Q1.

[0104] The operating state of the circuit breaker in this embodiment is the same as Figure 2 As described, the circuit breaker begins fault detection for at least one AC cycle after a preset time following AC circuit power-on, and performs fault detection at regular intervals to test whether the circuit breaker can function normally and provide circuit protection. Fault detection includes continuous connectivity testing and simulated leakage current testing during the positive and negative half-cycles of the AC power supply.

[0105] During fault detection, during the positive half-cycle of the AC power supply, the protection module 140 is tested for connectivity. The AC signal first passes through the solenoid SQL and diode D1 to reach the anode of the thyristor SQ1, generating a voltage on node Q1 as the first detection signal VS1. The self-test control module 120 receives the first detection signal VS1 from node Q1 and compares the voltage value of the first detection signal VS1 with the threshold voltage Vth1 to detect the connectivity between the solenoid SQL and the thyristor SQ1. When the voltage value of the first detection signal VS1 is less than the threshold voltage Vth1, it indicates that the solenoid SQL may be faulty. To avoid false alarms, connectivity tests will be performed in the following AC cycles, for example, repeatedly (e.g., 3 or more times, the number of tests depends on actual needs). If the voltage value of the first detection signal VS1 is less than the threshold voltage Vth1 in each connectivity test, the circuit breaker is considered faulty and leakage protection can no longer be performed. The self-test control module 120 generates an alarm signal to prompt the user to replace the circuit breaker. If the voltage value of the first detection signal VS1 reaches or exceeds the threshold voltage Vth1, the solenoid SQL and the thyristor SQ1 are connected normally, and a simulated leakage current test is performed in the negative half-cycle of the AC power supply. In the positive half-cycle of the AC power supply, the self-test control module 120 only receives the first detection signal VS1 and does not send a simulated leakage current signal Vleak.

[0106] During the negative half-cycle of the AC power supply, simulated leakage current detection is performed. The self-test control module 120 outputs a simulated leakage current signal Vleak to the induction module 110. In reality, the self-test control module 120 outputs the simulated leakage current signal Vleak to node Q2, causing a change in magnetic flux in the induction coil SC1. The induction module 110 generates a trigger signal Vtri based on the change in magnetic flux. The leakage current detection module 130 receives the trigger signal Vtri generated by the induction module 110 and outputs a conduction signal Vcon to the control terminal of the thyristor SQ1 of the protection module 140, turning on the thyristor SQ1 and generating a low voltage at node Q1, which serves as the second detection signal VS2. The self-test control module 120, connected to node Q1, receives the second detection signal VS2 and determines whether the leakage current detection module 130 and the protection module 140 are functioning normally. When the self-test control module 120 receives the second detection signal VS2, it indicates that the circuit breaker can perform normal leakage current protection, and the fault detection ends.

[0107] When the self-test control module 120 does not detect the second detection signal VS2, it indicates that the thyristor SQ1 is not conducting and there may be an internal fault in the circuit breaker. Therefore, it needs to be verified again. The circuit breaker will then undergo multiple (e.g., 3 or more, the number of tests depends on the actual needs) consecutive AC cycles of fault detection, and the simulated leakage current detection will be repeated multiple times. If the self-test control module 120 does not receive the second detection signal VS2 within the preset multiple AC cycles, it is determined that the circuit breaker has failed and leakage current protection can no longer be performed. At this time, the self-test control module 120 generates an alarm signal to prompt the user to replace the circuit breaker. Preferably, the second detection signal VS2 is low. For example, if the self-test control module 120 does not detect a low level at node Q1 during the first negative half-cycle of the AC power supply after a preset power-on time, then the fault detection for the second AC cycle is performed. If a low level is detected at node Q1, the fault detection ends. If a low level is still not detected at node Q1, then the fault detection for one or more AC cycles is performed, and the above steps are repeated until a preset number (e.g., the 4th) AC cycle of fault detection is performed and a low level is still not detected. Then, in the next AC cycle, the self-test control module 120 generates an alarm signal.

[0108] After power-on, the power supply delivers power to the circuit breaker and subsequent loads via the AC main line. After a preset power-on time, such as 1 or 2 seconds after power-on, fault detection begins. Continuous connectivity and simulated leakage current detection are performed alternately within one or more fixed positive and negative half-cycles of the AC power supply. Fault detection ends once the circuit breaker's leakage current protection function is confirmed to be normal. After the load has been operating for a period of time, such as 11.25 minutes, the circuit breaker re-enters alternating connectivity and simulated leakage current detection to continuously protect the user's safety. After another 11.25 minutes of normal power supply, fault detection resumes, and so on. For example, if an AC cycle is 20ms, then if the self-test control module 120 does not detect the second detection signal VS2 in the first AC cycle, it will continuously perform multiple preset (e.g., 3) AC cycles of simulated leakage current detection. If the second detection signal VS2 is still not detected after multiple (e.g., a total of 4) AC cycles of simulated leakage current detection, an alarm will be triggered after 80ms of fault detection (corresponding to 4 AC cycles). The alarm can be implemented in the form of LED flashing or buzzer beeping.

[0109] After a preset power-on time, connectivity testing and simulated leakage current testing begin. This testing only verifies the normal operation of the circuit breaker's leakage current protection function and does not affect its normal operation or leakage current protection function in the event of a leakage current. Furthermore, during any AC cycle of the AC power supply, when the current vector sum on the AC main line changes, a change in magnetic flux is generated at the coupling point between the main line and the induction coil SC1. The induction module 110 generates a trigger signal Vtri, which is output to the leakage current detection module 130. The leakage current detection module 130 receives the trigger signal Vtri and outputs a conduction signal Vcon to the control electrode of the thyristor SQ1 in the protection module 140. During the positive half-cycle of the AC circuit, diode D1 conducts, connecting the thyristor SQ1 and the solenoid SQL. The solenoid SQL generates electromagnetic force under the action of current, turning off switches S1 and S2, disconnecting the AC circuit, and preventing leakage current accidents.

[0110] Figure 4 Show Figure 3a and Figure 3b A detailed schematic circuit diagram of the circuit breaker. The circuit breaker is an instantiation of the block diagram in Figure 3. The circuit breaker includes a sensing module 110, a self-test control module 120, a leakage current detection module 130, a protection module 140, a rectifier bridge 150, and a manual self-test module 160.

[0111] Combination Figure 3a and Figure 3b In this embodiment, the self-test control module 120 includes a self-test control chip IC1 and multiple resistors and multiple capacitors, and the leakage current detection module 130 includes a leakage current detection chip IC2 and multiple resistors and capacitors.

[0112] The self-test control chip IC1 includes multiple pins, with 6 pins shown in the figure. Among them, fault pin 1 is connected to node Q2 through a series resistor R7 to output an analog leakage signal Vleak to node Q2; detection pin 4 is connected to node Q1 through a parallel diode D2 and a resistor R4 to receive the first detection signal VS1 and the second detection signal VS2; clock pin 2 is connected to the live wire L of the AC circuit through a resistor R6 to receive the AC signal from the live wire L and start timing. After a preset time, fault detection begins. After the estimated timing time, such as 1 or 2 seconds, clock pin 2 receives the AC signal from the live wire and processes it inside the self-test control chip IC1 to obtain the clock signal. The falling edge of the clock signal causes fault pin 1 to start working and emit an analog leakage signal Vleak. Power pin 3 is connected to a non-grounded output terminal of rectifier bridge 150 through resistor R5 to receive the voltage signal from rectifier bridge 150 and provide power to self-test control chip IC1. Alarm pin 5 is used to output an alarm signal when the circuit breaker fails. Ground pin 6 is used for grounding, and power pin 3 and ground pin 6 are connected through capacitor C3.

[0113] The leakage current detection chip IC2 includes multiple pins, with six pins shown in the figure. Pins 1 and 2 are used to receive the trigger signal Vtri. Pin 4 is connected to the control electrode of the silicon controlled rectifier (SQ1) and is used to output the conduction signal Vcon. Pins 1 and 2 are both connected to resistor R3 of the sensing module 110, and a resistor R2 is connected in series between pin 1 and resistor R3. Pin 3 is directly connected to the end of the induction coil SC1 without resistor R3. Pin 5 is connected to ground and the cathode of the SQ1. Pin 6 is connected to the rectifier bridge 150 through resistor R1, and the live wire L of the AC circuit supplies power to the leakage current detection chip IC2 through pin 6. Capacitor C1 is connected between pins 4 and 5 of the leakage current detection chip IC2, and capacitor C2 is connected between pins 5 and 6 of the leakage current detection chip IC2.

[0114] Furthermore, the circuit breaker continuously performs connectivity testing and simulated leakage current testing for at least one AC cycle after a preset power-on time. During fault detection, connectivity testing is performed on the protection module 140 during the positive half-cycle of the AC power supply. The AC signal passes through the solenoid SQL and diode D1 to reach the anode of the thyristor SQ1 and node Q1, and simultaneously connects to the detection pin 4 of the self-test control chip IC1. A voltage is generated at node Q1, which is the first detection signal VS1. Due to the forward conduction and reverse cutoff function of diode D2 of the self-test control chip IC1, diode D2 is cut off during the positive half-cycle of the AC power supply, and the forward voltage drop of diode D1 is small. The voltage at node Q1 is close to the power supply voltage. When the detection pin 4 detects the voltage at node Q1... If the actual voltage of the first detection signal VS1 does not reach the preset threshold voltage Vth1 (e.g., 60V), it is assumed that the solenoid SQL and the thyristor SQ1 may not be connected. To prevent false alarms, connectivity checks will be performed in the following AC cycles, for example, repeatedly (e.g., 3 or more times, depending on actual needs). If the voltage value of the first detection signal VS1 is less than the threshold voltage Vth1 in each connectivity check, a fault is detected, and the alarm pin 5 of the self-test control chip IC1 generates an alarm signal. When the detection pin 4 detects that the voltage value of the first detection signal VS1 at node Q1 is greater than or equal to the threshold voltage Vth1, it is assumed that the solenoid SQL is connected normally, and a simulated leakage current detection is performed. The voltage value of the first detection signal VS1 is greater than the threshold voltage, for example, by a high level or a pulse.

[0115] After the connectivity test passes, a simulated leakage current test is performed during the negative half-cycle of the AC power supply. The clock pin 2 of the self-test control chip IC1 processes the AC signal from the live wire L of the AC circuit to obtain a clock signal. When the clock signal is at its falling edge, the fault pin 1 sends the generated simulated leakage current signal Vleak to node Q2. Due to the characteristics of diode D1, diode D1 is cut off during the negative half-cycle of the AC power supply. The thyristor SQ1 and the solenoid SQL do not conduct, but are connected to the detection pin 4 through node Q1. At this time, the power supply pin 3 inside the self-test control chip IC1 is electrically connected to the detection pin 4. The power supply pin 3 supplies power to the detection pin 4. The voltages of the two are similar, for example, 5V, which can be equivalent to the two pins being connected through a resistor. The induction coil SC1 generates a trigger signal Vtri accordingly. Pin 1 of the leakage current detection chip IC2 receives the trigger signal Vtri and outputs a conduction signal Vcon to the control electrode of the thyristor SQ1 via pin 4, which is preferably the SCR pin. After the thyristor SQ1 is turned on, diode D2 pulls down the voltage at node Q1, causing a second detection signal VS2 to be generated at node Q1. At this time, detection pin 4 is used to receive the second detection signal VS2. The electrical connection between detection pin 4 and power supply pin 3 is disconnected, but power supply pin 3 still supplies power to the entire self-test control chip IC1. When detection pin 4 of the self-test control chip IC1 receives the second detection signal VS2, the simulated leakage current signal Vleak of fault pin 1 stops being sent, and one simulated leakage current detection is completed. Preferably, the second detection signal VS2 is low, and the voltage at node Q1 detected by detection pin 4 changes from high to low from the positive half-cycle to the negative half-cycle of the AC power supply. If the detection pin 4 of the self-test control chip IC1 does not receive the low-level second detection signal VS2 during the negative half-cycle of the AC power supply, the circuit breaker will repeat the simulated leakage current detection for multiple AC cycles. If the detection pin 4 of the self-test control module 120 does not receive the low-level second detection signal VS2 within the preset multiple AC cycles, the self-test control module 120 will generate an alarm signal. For example, four AC cycles of simulated leakage current detection can be performed. If the second detection signal VS2 is not detected in all four tests, the circuit breaker is considered to have malfunctioned. At the end of the fourth cycle and the beginning of the fifth AC cycle, the alarm pin 5 of the self-test control chip IC1 will generate an alarm signal.

[0116] This circuit breaker uses a self-test control module to provide a simulated leakage current signal, which activates the leakage current detection module, turns on the protection module, and determines whether the circuit breaker can work normally by detecting the voltage of the thyristor anode of the protection module. It can detect whether the circuit breaker can perform normal leakage current protection and play a role in protecting the circuit. The whole process is completed automatically after power-on, without manual intervention, which improves efficiency and protects the personal safety of users.

[0117] This circuit breaker begins fault detection for at least one AC cycle after a preset power-on time. During fault detection, the protection module is tested for connectivity during the positive half-cycle of the AC power supply to ensure timely alarm response in case of a fault. Simulated leakage current detection is performed during the negative half-cycle to check whether the leakage current detection module and protection module can provide leakage protection in case of a fault. These two tests are performed alternately during the positive and negative half-cycles of the AC power supply. An alarm signal is generated when the circuit breaker malfunctions, prompting the user to replace the circuit breaker and ensuring safety. Furthermore, this does not affect the normal protection function of the circuit breaker when a real circuit fault occurs; in the event of leakage current, the protection module can promptly disconnect the power supply.

[0118] Figure 5 The diagram shows the operating waveform of the circuit breaker when it is functioning normally during simulated leakage current detection according to an embodiment of the present invention. Figure 5 yes Figure 4 The embodiment describes the signal waveform diagrams of each pin of the circuit breaker during fault detection, combined with Figure 4 and Figure 5 The clock pin 2 of the self-test control chip IC1 is connected to the live wire L of the AC circuit through resistor R6. Therefore, it receives the AC signal from the live wire L and processes it into a clock signal CLK. The clock signal CLK is generated synchronously with the AC circuit. The clock signal CLK is a high-level square wave signal of approximately 6V. The period of the clock signal CLK represents the AC cycle of the AC circuit. The AC power supply is, for example, 110V / 60Hz or 220V / 50Hz. After a preset power-on time, the circuit breaker performs fault detection. The falling edge of the clock signal CLK transmitted by clock pin 2 causes fault pin 1 to send a simulated leakage current signal Vleak to node Q2 (at time t1 as shown in the figure), initiating simulated leakage current detection. When fault pin 1 does not generate the simulated leakage current signal Vleak, it is in a high-impedance state when the neutral voltage is greater than 0V, and the voltage is clamped near 0V when the neutral voltage is less than 0V.

[0119] like Figure 5 As shown, the t0-t1 time period is the positive half-cycle of the AC power supply. During the connectivity test, the AC signal reaches the anode of the thyristor SQ1 through the solenoid SQL and diode D1. The anode voltage of the thyristor SQ1 is relatively high, for example, 150V, and the detection pin 4 detects a high level.

[0120] At time t1, the negative half-cycle of the AC power supply begins, and simulated leakage current detection starts. This embodiment mainly describes the voltage changes of the signals received or generated by each pin during simulated leakage current detection. At the falling edge of the clock signal CLK, fault pin 1 sends a simulated leakage current signal Vleak to node Q2. During the negative half-cycle of the AC power supply, diode D1 is turned off, the anode voltage of the thyristor SQ1 drops, and the voltage detected by detection pin 4 decreases. However, detection pin 4 is connected to power supply pin 3 inside the self-test control chip IC1, and the detection voltage of detection pin 4 is basically the same as the voltage of power supply pin 3. Therefore, the detected voltage drops slightly and then rises again. The anode of the thyristor SQ1 is connected to detection pin 4 through node Q1, diode D2, and resistor R4. The voltage at node Q1 is about 0.7V lower than the voltage at detection pin 4 (the forward conduction voltage of diode D2).

[0121] Before time t2, the simulated leakage signal Vleak pulls down the voltage of the normal neutral line N. The induction coil SC1 generates a trigger signal Vtri based on the simulated leakage signal Vleak. The AC amplitude of the trigger signal Vtri is approximately 5mV. At this time, the detection voltage of detection pin 4 first decreases slightly and then increases again. At time t2, pin 1 of the leakage detection chip IC2 receives the trigger signal Vtri and outputs a conduction signal Vcon to the control electrode of the thyristor SQ1 through pin 4 (SCR pin). The conduction signal Vcon is a short pulse, approximately 700mV. The control electrode of the thyristor SQ1 receives the conduction signal Vcon and conducts. The internal electrical connection between detection pin 4 and power supply pin 3 is broken. Detection pin 4 detects the voltage of node Q1. At this time, detection pin 4 receives the second detection signal VS2 of node Q1. Since diode D2 is conducting, node Q1 pulls down the voltage of detection pin 4 through diode D2, so the voltage received by detection pin 4 drops to a low level. Therefore, it can be determined that the circuit breaker can perform normal leakage protection. The voltage of alarm pin 5 is low, so the fault detection ends. Fault pin 1 stops sending the simulated leakage signal Vleak. The effect of the simulated leakage signal Vleak on the voltage of the neutral line L disappears and returns to the original high level (about 150V). The trigger signal Vtri also returns to the original potential, and the fault detection ends.

[0122] The period from t0 to t1 is the positive half-cycle of the AC power supply, and the period from t1 to t3 is the negative half-cycle of the AC power supply. For example, if the AC cycle is 16.67ms, then the negative half-cycle of the AC power supply is approximately 8.33ms.

[0123] Figure 6 The diagram shows the operating waveform of the circuit breaker when a fault occurs during simulated leakage current detection according to an embodiment of the present invention.

[0124] Figure 6 yes Figure 4The embodiment described above illustrates the signal waveforms of each pin during fault detection in a circuit breaker that still performs fault detection even when an internal module malfunctions. The internal fault scenarios described here do not include open circuits in the solenoid SQL and short circuits in the thyristor SQ1; that is, the connectivity detection during the positive half-cycle is unaffected. Short circuits in the thyristor SQ1 and open circuits in the solenoid SQL will be addressed in the following scenarios. Figure 7a and Figure 7b Explanation will be provided. (In conjunction with...) Figure 4 and Figure 5 Fault detection begins at time t0, and connectivity testing is performed during the time interval t0-t1. The waveforms of each signal are shown below. Figure 5 The same applies. This embodiment mainly describes the voltage changes of the signals on each pin when a circuit breaker fault is detected during simulated leakage current detection.

[0125] At time t1, the negative half-cycle of the AC power supply begins, and the simulated leakage detection starts. Diode D1 is cut off, the anode voltage of the thyristor SQ1 drops, and the voltage of node Q1 detected by detection pin 4 drops. On the falling edge of the clock signal CLK, fault pin 1 sends a simulated leakage signal Vleak to node Q2. Detection pin 4 is connected to power pin 3 inside the self-test control chip IC1, and the voltages are similar, so a voltage waveform that changes from high to low and then rises again appears.

[0126] The analog leakage signal Vleak generated by fault pin 1 is related to the neutral voltage. It is a calculated voltage signal, obtained by subtracting the voltage waveform after the neutral voltage is pulled down from the normal neutral voltage waveform. Figure 6 The waveform of the simulated leakage current signal Vleak is shown in the figure.

[0127] During the time interval t1-t2, if the sensing module 110 functions normally, the induction coil SC1 generates a trigger signal Vtri based on the simulated leakage signal Vleak. Pin 1 of the leakage detection chip IC2 receives the trigger signal Vtri. However, due to a fault in other parts of the circuit breaker (e.g., a fault in the leakage detection chip IC2), the leakage detection chip IC2 cannot output a conduction signal Vcon to the control electrode of the thyristor SQ1. The level of the SCR pin remains low. At this time, since the thyristor SQ1 is not conducting, the voltage detected by the detection pin 4 remains unchanged, and the voltage of the detection pin 4 remains high. At this time, the circuit breaker prepares to perform fault detection for the next AC cycle to verify whether the circuit breaker has indeed malfunctioned. Therefore, the detection continues. At time t2, the positive half-cycle of the AC power supply begins, and the simulated leakage signal Vleak will not be generated.

[0128] During the time period t1-t2, if the sensing module 110 fails, the sensing coil SC1 cannot generate a trigger signal Vtri based on the simulated leakage current signal Vleak. The trigger signal Vtri is always 0, so the leakage current detection chip IC2 cannot output a conduction signal Vcon to the control electrode of the thyristor SQ1. The conduction signal Vcon on the SCR pin is always 0, consistent with the above description. At this time, the circuit breaker prepares to perform fault detection for the next AC cycle to verify whether the circuit breaker has indeed failed.

[0129] Therefore, regardless of which part of the circuit breaker malfunctions, if the detection pin 4 does not detect the low-level second detection signal VS2 at node Q1 after the thyristor SQ1 is turned on during the simulated leakage current detection phase, it is considered that the circuit breaker may be malfunctioning. Multiple cycles of simulated leakage current detection need to be performed again to confirm whether the circuit breaker is actually malfunctioning. Therefore, after time t2, whether the sensing module 110 is working normally has no effect on the voltage values ​​of other pins.

[0130] At time t2, a new AC cycle of fault detection begins. During the time period t2-t4, the trigger signal Vtri changes in the form of a half-sine wave, and the other signals are consistent with the waveform during the time period t0-t2.

[0131] Fault detection was performed in the third and fourth AC cycles during the time periods t4-t6 and t6-t8, respectively. The waveform changes of each signal during the time periods t4-t6 and t6-t8 were consistent with the waveform changes during the time period t2-t4.

[0132] At time t8, the fault detection of the fourth AC cycle ends. During the four simulated fault detection phases, the second low-voltage detection signal VS2 was not detected on detection pin 4, therefore the circuit breaker is considered faulty, and the fault detection ends. At this time, alarm pin 5 outputs an alarm signal, which is, for example, a square wave signal with a high level of 5V. The alarm signal can be represented by flashing LEDs or a buzzer; however, due to the short time period shown in the diagram, it is not shown as a square wave signal.

[0133] Figure 7a and Figure 7b The diagrams show the operating waveforms of the circuit breaker according to an embodiment of the present invention when the thyristor is short-circuited and the solenoid is open-circuited during connectivity testing.

[0134] like Figure 7aAs shown, connectivity testing begins at time t0. If the thyristor SQ1 is short-circuited, its anode voltage will remain 0, preventing it from conducting. The voltage detected by detection pin 4 will also remain 0, and no high-level first detection signal VS1 will be detected. Therefore, a potential circuit breaker malfunction is considered. Multiple AC cycles of connectivity testing are then required. Starting at time t2, another connectivity test is performed. After four AC cycles of connectivity testing (t0-t2, t2-t4, t4-t6, and t6-t8), no high-level first detection signal VS1 is detected by detection pin 4, confirming a circuit breaker malfunction. Therefore, at time t8, alarm pin 5 generates an alarm signal. The alarm signal is, for example, a square wave signal, displayed as a buzzer or a flashing LED. The high level of the square wave signal is, for example, 5V. Due to the short duration in the diagram, the square wave is not shown.

[0135] like Figure 7b As shown, connectivity testing begins at time t0. If the solenoid SQL is open, the anode voltage of the thyristor SQ1 will be 0 during connectivity testing, and the voltage detected by detection pin 4 will also be 0, indicating that the circuit breaker may be faulty. At time t1, the negative half-cycle of the AC power supply begins, and detection pin 4 detects the voltage of node Q1. Due to the presence of power supply pin 3, the voltage of detection pin 4 will be high.

[0136] At time t2, the positive half-cycle of the AC power supply begins again. To prevent false alarms, connectivity checks are performed for several other AC cycles, as shown in the time periods t2-t4, t4-t6, and t6-t8. During these three AC cycles, connectivity checks are repeated. In all three AC cycles, the voltage detected by detection pin 4 is 0, confirming a circuit breaker fault. Therefore, at time t8, a square wave alarm signal is generated.

[0137] The embodiments of the present invention are as described above. These embodiments do not exhaustively describe all details, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and variations can be made based on the above description. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to make good use of the present invention and modifications based on it. The scope of protection of the present invention should be determined by the scope defined in the claims of the present invention.

Claims

1. A circuit breaker for AC circuits, comprising: The self-test control module synchronously generates a simulated leakage current signal based on the AC signal and outputs it to the neutral wire of the AC circuit. The sensing module is coupled to the main line of the AC circuit and generates a trigger signal based on the change in magnetic flux at the coupling point; A leakage current detection module is connected to the sensing module to obtain the trigger signal and to generate a conduction signal based on the trigger signal; as well as The protection module is connected to the live wire of the AC circuit, the leakage current detection module, and the self-test control module, respectively. The protection module generates a first detection signal based on the AC signal during the positive half-cycle of the AC power supply, and generates a second detection signal based on the conduction signal during the negative half-cycle of the AC power supply, and outputs the first detection signal and the second detection signal to the self-test control module. The self-test control module determines the operating status of the circuit breaker based on the received first detection signal and second detection signal. During the positive half-cycle of the AC power supply, the self-test control module compares the voltage value of the first detection signal with the first threshold voltage and determines whether the circuit breaker has malfunctioned. During the negative half-cycle of the AC power supply, when the self-test control module receives the second detection signal, the fault detection ends; when the self-test control module does not receive the second detection signal, the circuit breaker performs simulated leakage current detection for multiple AC cycles to determine whether the circuit breaker has malfunctioned.

2. The circuit breaker according to claim 1, wherein, The protection module includes: A solenoid, connected between the live wire and the silicon controlled rectifier (SCR) of the AC circuit, is used to disconnect or connect the AC circuit; and A thyristor is connected between the solenoid and ground, and the control electrode of the thyristor is connected to the leakage current detection module to receive the conduction signal.

3. The circuit breaker according to claim 2, wherein, During the positive half-cycle of the AC power supply, when the change in the current vector sum on the main line of the AC circuit causes a change in magnetic flux at the coupling point, the sensing module generates the trigger signal and outputs it to the leakage detection module. The leakage detection module receives the trigger signal and outputs a conduction signal to the control electrode of the thyristor. The thyristor conducts according to the conduction signal and disconnects the AC circuit through the solenoid.

4. The circuit breaker according to claim 2, wherein, The protection module also includes: A first diode is connected in series between the thyristor and the solenoid, with the cathode of the first diode connected to the anode of the thyristor. The first diode is used to block the connection between the thyristor and the solenoid during the negative half-cycle of the AC power supply.

5. The circuit breaker according to claim 4, wherein, The circuit breaker begins fault detection for at least one AC cycle after the AC circuit is powered on for a preset time, and performs fault detection once at regular intervals. The fault detection includes continuous connectivity detection and simulated leakage current detection.

6. The circuit breaker according to claim 5, wherein, During the positive half-cycle of the AC power supply, the protection module is tested for connectivity. The AC signal passes through the solenoid to the anode of the thyristor, causing the first node between the thyristor and the first diode to generate the first detection signal.

7. The circuit breaker according to claim 6, wherein, During the positive half-cycle of the AC power supply, when the voltage value of the first detection signal is less than the first threshold voltage, the circuit breaker performs the connectivity test for multiple AC cycles. When the voltage value of the first detection signal remains less than the first threshold voltage during the connectivity test for multiple AC cycles, the self-test control module generates an alarm signal.

8. The circuit breaker according to claim 6, wherein, During the positive half-cycle of the AC power supply, when the voltage value of the first detection signal is greater than or equal to the first threshold voltage, the simulated leakage current detection is performed during the negative half-cycle of the AC power supply.

9. The circuit breaker according to claim 8, wherein, The simulated leakage current detection is performed during the negative half-cycle of the AC power supply. The self-test control module sends the generated simulated leakage current signal to the sensing module. The leakage current detection module receives the trigger signal generated by the sensing module and outputs a conduction signal to the thyristor to conduct the thyristor, so that a second detection signal is generated at the first node.

10. The circuit breaker according to claim 9, wherein, When the self-test control module does not receive the second detection signal, the circuit breaker performs simulated leakage current detection for multiple AC cycles. If the self-test control module does not receive the second detection signal within the preset multiple AC cycles, the self-test control module generates an alarm signal.

11. The circuit breaker according to claim 1, wherein, The first detection signal is high level, and the second detection signal is low level.

12. The circuit breaker according to claim 10, wherein, Also includes: The rectifier bridge is connected to the main line of the AC circuit and is used to provide power to the self-test control module and the leakage current detection module. A protective resistor is connected between the live wire and the neutral wire in the AC circuit. A switch is used to disconnect or connect the AC circuit under the control of the solenoid.

13. The circuit breaker according to claim 1, wherein, Also includes: A manual self-test module is connected between the live wire and the neutral wire of the AC circuit to manually test the operating status of the circuit breaker.

14. The circuit breaker according to claim 13, wherein, The manual self-test module includes an eighth resistor and a first self-test button connected in series.

15. The circuit breaker according to claim 10, wherein, The leakage current detection module includes: A leakage current detection chip, the leakage current detection chip including multiple pins, for receiving the trigger signal and outputting the conduction signal; The first resistor is connected between the sixth pin of the leakage current detection chip and the rectifier bridge; The second resistor is connected between the first pin of the leakage current detection chip and the sensing module. A first capacitor is connected between the fourth and fifth pins of the leakage current detection chip; and The second capacitor is connected between the fifth and sixth pins of the leakage current detection chip. The sixth pin serves as a power supply pin, through which the AC circuit supplies power to the leakage current detection chip via the rectifier bridge, the first resistor, and the sixth pin; the fifth pin is grounded, serving as a grounding pin; and the fourth pin serves as an output pin, providing the conduction signal.

16. The circuit breaker according to claim 15, wherein, The sensing module includes an induction coil coupled to the main line of the AC circuit, and a third resistor connected between a first end of the induction coil and a second resistor; the first end of the third resistor is connected to the induction coil, and the second end is connected to the first pin through the second resistor, and also to the second pin of the leakage current detection chip; the second end of the induction coil is connected to the third pin of the leakage current detection chip. The first and second pins are combined as a signal receiving pin to receive the trigger signal generated by the first end of the induction coil; the third pin is directly connected to the second end of the induction coil as a reference pin.

17. The circuit breaker according to claim 12, wherein, The self-test control module includes a self-test control chip, which has multiple pins. The fault pin is used to output the analog leakage signal; The detection pin is used to receive the first detection signal and the second detection signal; The alarm pin is used to output the alarm signal; The clock pin is used to receive AC signals from the AC circuit and generate a clock signal to start the faulty pin. The power supply pin is used to receive voltage signals from the rectifier bridge to power the self-test control chip.

18. The circuit breaker according to claim 17, wherein, The self-test control module also includes: A fourth resistor is connected between the detection pin and the first node; The fifth resistor is connected between the power supply pin and the rectifier bridge; The sixth resistor is connected between the clock pin and the live wire of the AC circuit; The seventh resistor is connected between the fault pin and the neutral wire of the AC circuit; A third capacitor is connected between the power supply pin and ground; and The second diode is connected in parallel across the fourth resistor.

19. The circuit breaker according to claim 18, wherein, The second diode of the self-test control module is cut off during the positive half-cycle of the AC power supply, and during the negative half-cycle of the AC power supply during the simulated leakage current detection, the detection pin detects the second detection signal of the first node.

20. The circuit breaker according to claim 17, wherein, After the detection pin of the self-test control module receives the second detection signal, it stops sending the simulated leakage current signal of the fault pin, and the simulated leakage current detection is completed.

21. A method for detecting the operating status of a circuit breaker, comprising: Connectivity detection is performed during the positive half-cycle of the AC power supply, and the protection module generates the first detection signal based on the AC signal. The self-test control module performs simulated leakage current detection, generating a simulated leakage current signal during the negative half-cycle of the AC signal, which causes a change in magnetic flux. The leakage current detection module obtains a trigger signal generated based on the change in magnetic flux, and generates a conduction signal based on the trigger signal. During the negative half-cycle of the AC power supply, the protection module generates a second detection signal based on the conduction signal; as well as The self-test control module determines the operating status of the circuit breaker based on the received first and second detection signals. During the positive half-cycle of the AC power supply, the self-test control module compares the voltage value of the first detection signal with the first threshold voltage and determines whether the circuit breaker has malfunctioned. During the negative half-cycle of the AC power supply, when the self-test control module receives the second detection signal, the fault detection ends. When the self-test control module does not receive the second detection signal, the circuit breaker performs multiple AC cycles of simulated leakage current detection to determine whether the circuit breaker has malfunctioned.

22. The working status detection method according to claim 21, wherein, Also includes: After a preset power-on time, fault detection begins for at least one AC cycle, wherein the fault detection includes continuous connectivity detection and simulated leakage current detection.

23. The working status detection method according to claim 22, wherein, Connectivity testing is performed, and a first detection signal is generated based on the AC signal, including: During the positive half-cycle of the AC power supply, the AC signal passes through the first node to generate the first detection signal; When the voltage value of the first detection signal is greater than or equal to the first threshold voltage, the simulated leakage current detection is performed; When the voltage value of the first detection signal is less than the first threshold voltage, a connectivity test is performed for multiple AC cycles. If the voltage value of the first detection signal is still less than the first threshold voltage during the multiple AC cycles of connectivity test, an alarm signal is generated.

24. The working status detection method according to claim 22, wherein, Generating a second detection signal based on the conduction signal, and determining the operating state of the circuit breaker based on the received second detection signal includes: During the negative half-cycle of the AC power supply, the trigger signal is generated based on the simulated leakage current signal; A conduction signal is generated based on the trigger signal; Output the conduction signal to generate a second detection signal at the first node; If the second detection signal is not received, the simulated leakage current detection is performed for multiple AC cycles. If the second detection signal is not received within the preset multiple AC cycles, an alarm signal is generated.

25. The working status detection method according to claim 24, wherein, Upon receiving the second detection signal, the simulated leakage signal stops being transmitted, and the simulated leakage detection is completed.

26. The working status detection method according to claim 21, wherein, Also includes: During the positive half-cycle of the AC power supply, when the change in current on the main line of the AC circuit generates a change in magnetic flux, the trigger signal is output. Receive the trigger signal and output a conduction signal; The AC circuit is disconnected according to the conduction signal.

27. The working status detection method according to claim 21, wherein, The first detection signal is high level, and the second detection signal is low level.

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