Leakage protection device

Abstract

The disclosure provides a leakage protection device. The leakage protection device comprises a switch module coupled between an input end and an output end of a power line and configured to control the power connection between the input end and the output end; a leakage detection module coupled to the power line and configured to detect a leakage current signal on the power line and output a detection signal; a leakage processing module coupled to the leakage detection module and configured to receive the detection signal and output a leakage fault signal corresponding to the amplitude and frequency of the detection signal; and a driving module coupled to the leakage processing module and the switch module and configured to receive the leakage fault signal and drive the switch module to disconnect the power connection between the input end and the output end in response to the leakage fault signal. The disclosure solves the problem of false tripping of the device under high-frequency use conditions and improves the user experience.

Description

Technical Field

[0001] The present disclosure relates to the field of electrical safety, and in particular to a leakage protection device. Background Art

[0002] With the increasing popularity of household appliances, people are paying more and more attention to their safety. Many appliances are now equipped with leakage protection devices (such as leakage protection plugs). The diverse range of household appliances on the market today, with complex internal circuits, can generate currents of varying frequencies in the main circuit. High-frequency currents are less harmful to the human body than low-frequency currents. However, in actual use, high-frequency currents can easily generate parasitic currents to the ground and significantly interfere with leakage protection devices, potentially causing product malfunctions during use, impacting the user experience and posing safety risks.

[0003] Therefore, there is an urgent need to propose a new type of leakage protection device to solve the problem of false tripping of existing leakage protection devices in an environment where high-frequency current is generated, improve user experience, and eliminate safety hazards. Summary of the Invention

[0004] To solve at least part of the problems in the prior art, the present disclosure proposes a leakage protection device. The leakage protection device includes: a switch module, which is coupled between an input end and an output end of a power line and is configured to control the power connection between the input end and the output end; a leakage detection module, which is coupled to the power line and is configured to detect a leakage current signal on the power line and output a detection signal; a leakage processing module, which is coupled to the leakage detection module and is configured to receive the detection signal, determine a target gain based on the frequency of the detection signal to perform a gain operation on the amplitude of the detection signal, and compare the result of the gain operation with a preset threshold, thereby outputting a leakage fault signal based on the comparison result; and a driving module, which is coupled to the leakage processing module and the switch module and is configured to receive the leakage fault signal and, in response to the leakage fault signal, drive the switch module to disconnect the power connection between the input end and the output end.

[0005] In some embodiments, the leakage processing module includes: a first leakage processing unit, configured to receive and process a first signal in a first frequency range in the detection signal; and a second leakage processing unit, configured to receive and process a second signal in a second frequency range in the detection signal.

[0006] In some embodiments, the first leakage current processing unit includes a leakage current chip, and the second leakage current processing unit includes a micro control unit.

[0007] In some embodiments, the leakage detection module includes a first filtering circuit. The detection signal is filtered by the first filtering circuit and then input into the leakage chip. The detection signal is amplified by the leakage chip and then input into the micro control unit.

[0008] In some embodiments, the leakage detection module includes an operational amplifier circuit and a second filtering circuit. The detection signal is amplified by the operational amplifier circuit and then input into the microprocessing unit. The detection signal is amplified by the operational amplifier circuit and then filtered by the second filtering circuit before being input into the leakage chip.

[0009] In some embodiments, the leakage protection device further includes a self-test module, which is coupled to the leakage detection module and the driving module, and is configured to generate a self-test signal to be sent to the leakage detection module, and to control the driving module to drive the switch module to disconnect the power connection when a failure occurs in the leakage detection module, the leakage processing module and / or the driving module.

[0010] In some embodiments, the power line includes a first current-carrying line connected to the live line of the power grid and a second current-carrying line connected to the neutral line of the power grid. The driving module includes a trip coil and a thyristor. The first end of the trip coil is connected to the first current-carrying line, and the second end of the trip coil is connected to the thyristor. The self-test module includes a protection diode and a protection resistor. The second end of the trip coil is connected to the control end of the thyristor via the protection diode and the protection resistor, so that when a fault occurs in the leakage processing module, the current passes through the first current-carrying line, the trip coil, the protection diode and the protection resistor to drive the thyristor to turn on, thereby driving the switch module to disconnect the power connection between the input end and the output end.

[0011] In some embodiments, the self-test module includes: a microcontroller unit, which is coupled to the leakage detection module and configured to periodically output an analog current signal to the leakage detection module and receive a corresponding feedback signal from the leakage detection module to output a self-test fault signal when a fault occurs in the leakage detection module and / or the leakage processing module to control the driving module to drive the switching module to disconnect the power connection between the input end and the output end.

[0012] In some embodiments, the self-test module further includes a self-test resistor coupled to the micro control unit and configured to pre-adjust the value of the analog current signal.

[0013] In some embodiments, the leakage processing module includes a leakage chip, which is configured to receive the detection signal, determine the target gain based on the frequency of the detection signal to perform a gain operation on the amplitude of the detection signal, and compare the result of the gain operation with a preset threshold, thereby outputting a leakage fault signal based on the comparison result.

[0014] The leakage protection device proposed in the present disclosure can perform different gain processing on the amplitude of the leakage current according to the frequency, making the device more sensitive to leakage currents with lower frequencies and relatively insensitive to leakage currents with higher frequencies, thereby effectively solving the problem of false tripping of the device under high-frequency use conditions, improving the user experience, and eliminating safety hazards. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The embodiments are shown and explained with reference to the accompanying drawings. These drawings are intended to illustrate the basic principles and only show aspects necessary for understanding the basic principles. The drawings are not to scale. In the drawings, the same reference numerals represent similar features. In addition, a line connecting each block in an architectural diagram indicates that the two blocks are electrically coupled; the absence of a line between two blocks does not indicate that the two blocks are not coupled.

[0016] Figure 1 The figure shows an architecture diagram of a leakage protection device according to an embodiment of the present disclosure.

[0017] Figure 2 A schematic diagram of a first embodiment of a leakage protection device according to the present disclosure is shown;

[0018] Figure 3 shows a principle diagram of a second embodiment of a leakage protection device according to the present disclosure;

[0019] Figure 4 A schematic diagram showing a third embodiment of a leakage protection device according to the present disclosure; and

[0020] Figure 5 A schematic diagram of a fourth embodiment of a leakage protection device according to the present disclosure is shown. DETAILED DESCRIPTION

[0021] In the following detailed description of the preferred embodiments, reference will be made to the accompanying drawings which form part of this disclosure. The accompanying drawings illustrate, by way of example, specific embodiments in which the present disclosure may be implemented. The illustrated embodiments are not intended to be exhaustive of all embodiments according to the present disclosure. It will be understood that other embodiments may be utilized and structural or logical modifications may be made without departing from the scope of the present disclosure. Therefore, the following detailed description is not restrictive, and the scope of the present disclosure is defined by the appended claims.

[0022] Before introducing the embodiments of the present disclosure, some terms involved in the present disclosure are first explained to facilitate a better understanding of the present disclosure.

[0023] As used herein, the terms "connect," "couple," or "coupled" and similar terms are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms "a," "a," or "a" and similar terms do not indicate a limitation of quantity, but rather indicate the presence of at least one.

[0024] The terms "include", "comprising" and similar terms used in this disclosure should be understood as open terms, that is, "including / includes but not limited to", indicating that other content may also be included. The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment" and so on. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in an appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0025] This disclosure aims to provide a leakage protection device. This device can apply different gain processing to the leakage current amplitude based on frequency, making the device more sensitive to leakage currents at lower frequencies and less sensitive to leakage currents at higher frequencies. This effectively resolves the issue of false tripping during high-frequency operation, improves the user experience, and eliminates safety hazards. This leakage protection device has a simple circuit structure, low cost, and high safety.

[0026] Figure 1 FIG. 1 shows an architecture diagram of a leakage protection device according to an embodiment of the present disclosure. Figure 1As shown, the leakage protection device 100 includes a switch module 103, a leakage detection module 104, a leakage processing module 105, and a driver module 106. The switch module 103 is coupled between the input terminal 101 and the output terminal 102 of the power line and is configured to control the power connection between the input terminal 101 and the output terminal 102. The leakage detection module 104 is coupled to the power line and is configured to detect a leakage current signal on the power line and output a detection signal. The leakage processing module 105 is coupled to the leakage detection module 104 and is configured to receive the detection signal, determine a target gain based on the frequency of the detection signal, perform a gain operation on the amplitude of the detection signal, compare the gain operation result with a preset threshold, and output a leakage fault signal based on the comparison result. The driver module 106 is coupled to the leakage processing module 105 and the switch module 103 and is configured to receive the leakage fault signal and, in response to the leakage fault signal, drive the switch module 103 to disconnect the power connection between the input terminal and the output terminal of the power line.

[0027] It should be noted that the leakage processing module 105 can implement the above-mentioned processing of the detection signal by configuring existing hardware such as a leakage chip, that is, receiving the detection signal, and performing a gain operation on the amplitude of the detection signal based on different target gains corresponding to different frequencies of the detection signal, and comparing the result of the gain operation with a preset threshold, thereby outputting a leakage fault signal based on the comparison result. In other examples, the above-mentioned processing of the detection signal can be implemented by combining and connecting existing hardware such as a selection switch, a proportional amplifier, and a comparator.

[0028] In some examples, the leakage protection device 100 further includes a self-test module 107. The self-test module 107 is coupled to the leakage detection module 104 and the driving module 106, and is configured to generate a self-test signal to be sent to the leakage detection module 104, and to control the driving module 106 to drive the switch module 103 to disconnect the power connection between the input and output ends of the power line when a fault occurs in the leakage detection module 104, the leakage processing module 105, and / or the driving module 106.

[0029] In some examples, the leakage processing module 105 includes a first leakage processing unit and a second leakage processing unit, wherein the first leakage processing unit is configured to receive and process a first signal in a first frequency range in a detection signal (first voltage signal); and the second leakage processing unit is configured to receive and process a second signal in a second frequency range in the detection signal. This example satisfies the requirements of the leakage protection device for different protection thresholds and different action response times corresponding to leakage currents of different frequencies by performing different signal processing. For example, the preset protection threshold is 6mA, and the first leakage processing unit can be configured to process a 60Hz leakage current signal, and output a leakage fault signal when the amplitude of the 60Hz leakage current signal is greater than 6mA; the second leakage processing unit can be configured to process leakage current signals of other higher frequencies such as 1kHz, 10kHz, 50kHz and / or 150kHz, and output a leakage fault signal when the amplitude of the 1kHz leakage current signal is divided by a gain of 1.2 is greater than 6mA, and output a leakage fault signal when the amplitude of the 10kHz leakage current signal is divided by a gain of 5 is greater than 6mA, and so on, and leakage current signals of other frequencies are divided by the corresponding gain. In some examples, the first leakage processing unit is a leakage chip, and the second leakage processing unit is a microcontroller unit. When the leakage current is detected, the leakage chip can control the switch module to disconnect the power connection of the power line in a shorter time (for example, within 40ms), and the leakage protection action has a faster response speed and higher safety.

[0030] In some examples, the leakage detection module 104 includes a first filter circuit, and the detection signal is filtered by the first filter circuit and input into the leakage chip, and then amplified by the leakage chip and input into the micro-control unit. In other examples, the leakage detection module 104 includes an op amp circuit and a second filter circuit, and the detection signal is amplified by the op amp circuit and input into the micro-processing unit, and then amplified by the op amp circuit and filtered by the second filter circuit and input into the leakage chip. The two types of examples can be respectively applied to the user's application needs in different scenarios, wherein the leakage protection device including the first filter circuit is suitable for application scenarios with a smaller leakage frequency protection range, and the leakage protection device including the second filter circuit is suitable for application scenarios with a larger leakage frequency protection range.

[0031] Figure 2 FIG. 1 shows a schematic diagram of a first embodiment of a leakage protection device according to the present disclosure. Figure 2 As shown, the leakage protection device 200 includes a switch module 103, a leakage detection module 104, a leakage processing module 105, a driving module 106 and a self-test module 107. The power line includes a first current-carrying line 11 and a second current-carrying line 12. Figure 2As shown, the switch module 103 includes a reset switch RESET, which is used to control the power connection between the input and output ends of the first current-carrying line 11 and the second current-carrying line 12. The leakage detection module 104 includes zero-sequence current transformers CT1 and CT2, through which the first and second current-carrying lines 11 and 12 pass, as well as an operational amplifier U1 and its peripheral circuits. These are used to detect leakage current signals on the first and second current-carrying lines 11 and 12, amplify them through the operational amplifier circuit U1, and output corresponding detection signals. The leakage processing module 105 uses a microcontroller unit U2 to receive the detection signals, determine a target gain based on the frequency of the detection signals, perform a gain calculation on the amplitude of the detection signals, compare the gain calculation result with a preset threshold, and output a leakage fault signal based on the comparison result. The leakage processing module 105 also includes a power supply circuit (resistor R2 connected to the input end of the first current-carrying line 11, capacitor C3, rectifier DB1, and voltage regulator diode ZD1) to power the microcontroller unit U2. The driver module 106 includes a trip coil SOL1, a trip coil SOL2, and thyristors Q1 and Q2. SOL1 and SOL2 serve as backup devices for each other, and Q1 and Q2 serve as backup devices for each other. By controlling the conduction of Q1 and Q2, the current flowing through SOL1 and SOL2 is controlled, thereby driving the switch module 103 on and off. The self-test module 107 includes a microcontroller unit U2 and a self-test resistor R5. Pin 8 of the microcontroller unit U2 periodically outputs an analog current signal, which is coupled to CT1 via the self-test resistor R5 and receives the corresponding feedback signal from the leakage detection module 104. When a fault occurs in the leakage detection module 104 and / or the leakage processing module 105, the microcontroller unit U2 is output as a self-test fault signal, thereby controlling the driver module 106 to drive the switch module 103 to disconnect the power connection between the input and output ends of the power line. The microcontroller unit U2 in the self-test module 107 can also be replaced with another chip independent of the leakage processing module to implement the corresponding self-test function.

[0032] Under normal operating conditions, first current-carrying line 11 is connected to the live line of the power grid, second current-carrying line 12 is connected to the neutral line of the power grid, and switch module 103 is in a reset state (i.e., closed). The input and output terminals of first and second current-carrying lines 11 and 12 are connected, and auxiliary reset switch SW1 (linked to reset switch RESET) is disconnected. In this state, current flows through first current-carrying line 11, R2, C3, DB1, and ZD1 to establish a stable operating power supply, powering microprocessor unit U2 and op amp U1, and pins 7 and 5 of microprocessor unit U2 output a low level.

[0033] When the switch module 103 is in the off state, SW1 is closed by pressing the reset button, and the current drives Q1 and Q2 to turn on through DB1-R12-SW1, so that SOL1 and SOL2 are turned on, thereby driving the switch module 103 to unlock. The switch module 103 connects the power connection between the input and output ends of the power line, the device is reset successfully, and SW1 is disconnected.

[0034] When leakage occurs in the first current-carrying line 11 (L) and / or the second current-carrying line 12 (N), CT1 or CT2 detects a leakage current signal, which is amplified by U1 to generate a detection signal (a first voltage signal). The detection signal is transmitted to the AD conversion port (pin 1) of U2, and U2 processes the detection signal to obtain the frequency and amplitude of the detection signal, and converts the amplitude into a corresponding gain according to its frequency to obtain an equivalent leakage current value, and then compares the equivalent leakage current value with the stored equivalent tripping threshold (for example, the tripping threshold of the 60Hz leakage current is 6mA and the 1kHz leakage current is 6mA). When the tripping threshold for leakage current is 7.2mA and the tripping threshold for 10kHz leakage current is 30mA, an equivalent tripping threshold of 6mA is stored in U2. When the leakage current frequency is detected to be 60Hz, no attenuation gain calculation is performed on the current amplitude; when the leakage current frequency is detected to be 1kHz, the current amplitude is divided by 1.2 for attenuation gain calculation; when the leakage current frequency is detected to be 10kHz, the current amplitude is divided by 5 for attenuation gain calculation. Similarly, corresponding gain calculations are performed on the amplitudes of the leakage current signals at each frequency, and finally the calculated equivalent leakage current value is compared with the equivalent tripping threshold of 6mA. When the equivalent leakage current value after the gain calculation exceeds the equivalent tripping threshold, a high level is output through pin 5 of U2, triggering Q1 and Q2 to turn on, causing SOL1 and SOL2 to draw large current and generate a magnetic field to drive the switch module 103 to disconnect the power connection between the input and output ends of the power line.

[0035] Furthermore, the leakage current treatment device 200 implements a self-test function through the self-test module 107. Specifically, the processor U2 regularly outputs a high level at pin 8, which is coupled to CT1 through the self-test resistor R5 and then grounded to form a current loop to generate an analog leakage current signal. Under normal circumstances, when CT1 collects the analog leakage current signal, it is amplified by U1 and transmitted to the microprocessor unit U2. U2 receives the feedback signal to keep the pin 7 output low, Q1 and Q2 are not turned on, and the switch module 103 remains in the on state. When the original components such as CT1 and / or U1 are damaged, U2 does not receive the feedback signal, and the pin 7 of U2 is set to a high level, so that Q1 and Q2 are turned on, and the switch module 103 disconnects the power connection between the input and output ends of the power line. When components such as R2, C3, DB1 and / or ZD1 in the power supply circuit are damaged, causing U2 to fail to work, or when U2 itself is damaged, pin 7 of U2 cannot output a low level, and the current drives the thyristor Q1 and / or Q2 to turn on through the first current-carrying line 11, the trip coil SOL1 and / or SOL2, the protection diode D2 and the protection resistor R8, so that SOL1 and / or SOL2 obtain a large current and generate a magnetic field, driving the switch module 103 to disconnect the power connection between the input end and the output end of the power line.

[0036] Figure 3 FIG. 2 shows a schematic diagram of a second embodiment of a leakage protection device according to the present disclosure. Figure 3 As shown, the leakage protection device 300 includes a switch module 103 , a leakage detection module 104 , a leakage processing module 105 , a driving module 106 and a self-test module 107 . Figure 3 and Figure 2 The working principle is similar, only the differences are explained here. Figure 3 and Figure 2 The difference is that Figure 2 The output end includes the socket end and the load end. Figure 3 The output end is the socket end, that is Figure 2 and Figure 3 The leakage protection devices are suitable for different products. Figure 2 The load-end products have higher requirements for leakage protection. Figure 3 Only the socket end product is higher. Therefore, Figure 3 The auxiliary reset switch SW1 (normally closed switch) can be connected in series between the input end of the first current-carrying line 11 and the tripping coil SOL1. Figure 3 The driver module 106 in the device has only one trip coil SOL1. The leakage protection device 300 may also include a fault indication circuit R13 and a light-emitting diode (LED). R13 and the LED are connected in series, with the first end of R13 connected to SOL1, the second end of R13 connected to the input of the LED, and the output of the LED grounded. When a fault occurs, the LED turns off, indicating a circuit failure.

[0037] Figure 4 FIG. 1 shows a schematic diagram of a third embodiment of a leakage protection device according to the present disclosure. Figure 4 As shown, the leakage protection device 400 includes a switch module 103 , a leakage detection module 104 , a leakage processing module 105 , a driving module 106 and a self-test module 107 . Figure 4 and Figure 2 The working principle is similar, only the differences are explained here. Figure 4 The leakage detection module 104 does not include the operational amplifier circuit U1. Figure 4 The leakage processing module 105 adds a leakage chip U3 to amplify the leakage current signal, and the first voltage signal of some frequency bands is also processed by the built-in circuit of the leakage chip U3. During normal operation, the current establishes a stable working power supply through R2-C3-DB1-ZD1 to power U2 and the leakage chip U3. The leakage detection module 104 adds a first filtering circuit. Specifically, the first end of the secondary side of CT1 is connected to pin 1 of U3 via inductor L1 and capacitor C8, the second end of the secondary side of CT1 is connected to pin 3 of U3 via inductor L2, the first end of capacitor C10 is connected to pin 7 of U3, and the second end of capacitor C10 is connected to pin 1 of U3. L1 and C8 form a first filtering circuit to filter the detected leakage current signal and then input it into the leakage chip U3.

[0038] When leakage current occurs in the first current-carrying line 11 (L) and / or the second current-carrying line 12 (N), CT1 or CT2 detects the leakage current signal, which is amplified by U3 to generate a first voltage signal and transmitted to the AD conversion port (pin 2) of U2. The frequency and amplitude of the first voltage signal are obtained through U2 processing, and the amplitude is converted into an equivalent leakage current value according to its frequency. The equivalent leakage current value is compared with the stored equivalent tripping threshold. When the equivalent leakage current value exceeds the equivalent tripping threshold, a high level is output through pin 5 of U2, triggering Q1 and / or Q2 to turn on, so that SOL1 and / or SOL2 obtain a large current and generate a magnetic field to drive the switch module 103 to disconnect the power connection between the input and output ends of the power line. In addition, the first voltage signal of some frequency bands can be processed by the built-in circuit of the leakage chip U3: when the amplitude corresponding to the first voltage signal of the frequency band exceeds the built-in set threshold of U3, pin 5 of U3 outputs a high level, triggering Q1 and / or Q2 to turn on, so that SOL1 and / or SOL2 obtain a large current and generate a magnetic field to drive the switch module 103 to disconnect the power connection between the input and output ends of the power line.

[0039] Figure 5 FIG. 4 shows a schematic diagram of a fourth embodiment of a leakage protection device according to the present disclosure. Figure 5As shown, the leakage protection device 500 includes a switch module 103 , a leakage detection module 104 , a leakage processing module 105 , a driving module 106 and a self-test module 107 . Figure 5 and Figure 1 The working principle is similar, only the differences are explained here. Figure 5 The leakage detection module 104 in the system now includes a second filter circuit and a leakage chip U3. The second filter circuit includes an inductor L1 and a capacitor C8. The first end of L1 is connected to the output of op amp U1, and the second end of L1 is connected to ground via capacitor C8. The first and second ends of C8 are connected to pins 7 and 8 of U3, respectively. Pin 6 is the power supply for U3 (powered by the input of the first current-carrying line through R2, C3, and DB1). During normal operation, current flows through R2-C3-DB1-ZD1 to establish a stable operating power supply, powering U2, U1, and the leakage chip U3.

[0040] When leakage current occurs in the first current-carrying line 11 and / or the second current-carrying line 12, CT1 detects the leakage signal. The leakage current signal is amplified by U1 to generate a first voltage signal. The first voltage signal is transmitted to the AD conversion port (pin 1) of U2. U2 processes the frequency and amplitude of the first voltage signal and converts the amplitude into a corresponding gain according to its frequency to obtain an equivalent leakage current value. The equivalent leakage current value is compared with the stored equivalent tripping threshold. When the equivalent tripping threshold is exceeded, a high level is output through pin 5, triggering Q1 and / or Q2 to turn on, causing SOL1 and / or SOL2 to draw a large current and generate a magnetic field to drive the switch module 103 to disconnect the power connection between the input and output ends of the power line. The first voltage signal of a certain frequency band can also be processed by the built-in circuit of the leakage current chip U3. When the threshold exceeds the built-in set threshold of U3, a high level is output through pin 5 of U3, triggering Q1 and / or Q2 to turn on, causing SOL1 and / or SOL2 to draw a large current and generate a magnetic field to drive the switch module 103 to disconnect the power connection between the input and output ends of the power line. Among them, the first voltage signal can also be processed by the leakage chip U3 after filtering by L1 and C8. When the amplitude of the first voltage signal exceeds the built-in set threshold of U3, pin 5 of U3 outputs a high level, triggering Q1 and / or Q2 to turn on, so that SOL1 and / or SOL2 obtain a large current and generate a magnetic field to drive the switch module 103 to disconnect the power connection between the input end and the output end of the power line.

[0041] This document is described with reference to various exemplary embodiments. However, those skilled in the art will recognize that changes and modifications may be made to the exemplary embodiments without departing from the scope of this document. Although the principles of this document have been illustrated in various embodiments, many modifications of the structure, arrangement, proportions, elements, materials, and components that are particularly suitable for specific environments and operational requirements may be used without departing from the principles and scope of this disclosure. The above modifications and other changes or modifications are intended to be included within the scope of this document. The foregoing detailed description has been described with reference to various embodiments. However, those skilled in the art will recognize that various modifications and changes may be made without departing from the scope of this disclosure. Therefore, consideration of this disclosure will be in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within its scope. Similarly, the advantages, other advantages, and solutions to problems of the various embodiments have been described above. However, the benefits, advantages, solutions to problems, and any elements that produce these, or make them more specific, should not be interpreted as critical, required, or essential. As used herein, the term "comprise" and any other variations thereof are intended to be non-exclusive, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not expressly listed or not part of the process, method, system, article, or apparatus. Additionally, as used herein, the term "couple" and any other variations thereof refer to a physical, electrical, magnetic, optical, communicative, functional, and / or any other connection.

[0042] Those skilled in the art will recognize that many changes can be made to the details of the above embodiments without departing from the basic principles of the present disclosure. Therefore, the scope of the present disclosure should be determined solely by the claims.

Claims

1. A leakage protection device, characterized in that: include: a switch module coupled between an input end and an output end of the power line and configured to control a power connection between the input end and the output end; a leakage detection module coupled to the power line and configured to detect a leakage current signal on the power line and output a detection signal; a leakage processing module coupled to the leakage detection module and configured to receive the detection signal, determine a target gain based on the frequency of the detection signal to perform a gain operation on the amplitude of the detection signal, compare the result of the gain operation with a preset threshold, and output a leakage fault signal based on the comparison result; The driving module is coupled to the leakage processing module and the switch module and is configured to receive the leakage fault signal and drive the switch module to disconnect the power connection between the input terminal and the output terminal in response to the leakage fault signal.

2. The leakage protection device according to claim 1, characterized in that: The leakage processing module includes: a first leakage processing unit, configured to receive and process a first signal in a first frequency range in the detection signal; The second leakage processing unit is configured to receive and process a second signal in a second frequency range in the detection signal.

3. The leakage protection device according to claim 2, characterized in that: The first leakage processing unit includes a leakage chip, and the second leakage processing unit includes a micro control unit.

4. The leakage protection device according to claim 3, characterized in that: The leakage detection module includes a first filter circuit. The detection signal is filtered by the first filter circuit and then input into the leakage chip. The detection signal is amplified by the leakage chip and then input into the micro control unit.

5. The leakage protection device according to claim 3, characterized in that: The leakage detection module includes an operational amplifier circuit and a second filtering circuit. The detection signal is amplified by the operational amplifier circuit and then input into the micro control unit. The detection signal is amplified by the operational amplifier circuit and then filtered by the second filtering circuit before being input into the leakage chip.

6. The leakage protection device according to claim 1, characterized in that: Also includes: a self-test module coupled to the leakage detection module and the driving module and configured to generate a self-test signal to be sent to the leakage detection module, and to control the driving module to drive the switch module to disconnect the power connection when a failure occurs in the leakage detection module, the leakage processing module and / or the driving module.

7. The leakage protection device according to claim 6, characterized in that: The power line includes a first current-carrying line connected to the live line of the power grid and a second current-carrying line connected to the neutral line of the power grid. The driving module includes a trip coil and a thyristor. The first end of the trip coil is connected to the first current-carrying line, and the second end of the trip coil is connected to the thyristor. The self-test module includes a protection diode and a protection resistor. The second end of the trip coil is connected to the control end of the thyristor via the protection diode and the protection resistor. When a fault occurs in the leakage processing module, current passes through the first current-carrying line, the trip coil, the protection diode, and the protection resistor to drive the thyristor to conduct, thereby driving the switch module to disconnect the power connection between the input end and the output end.

8. The leakage protection device according to claim 6, characterized in that: The self-test module includes: a microcontrol unit coupled to the leakage detection module and configured to periodically output an analog current signal to the leakage detection module and receive a corresponding feedback signal from the leakage detection module so as to output a self-test fault signal when a fault occurs in the leakage detection module and / or the leakage processing module, thereby controlling the driving module to drive the switch module to disconnect the power connection between the input end and the output end.

9. The leakage protection device according to claim 8, characterized in that: The self-test module further includes: A self-test resistor is coupled to the micro control unit and is configured to pre-adjust the value of the analog current signal.

10. The leakage protection device according to claim 1, characterized in that: The leakage processing module includes a leakage chip, which is configured to: receive the detection signal, determine the target gain based on the frequency of the detection signal to perform a gain operation on the amplitude of the detection signal, and compare the result of the gain operation with a preset threshold, thereby outputting a leakage fault signal based on the comparison result.

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