Earth leakage protection circuit and circuit breaking device

Abstract

The utility model provides an electric leakage protection circuit and a circuit breaking device, and relates to the technical field of integrated circuits, the electric leakage protection circuit comprises a zero sequence current transformer, a first leakage current acquisition unit, a second leakage current acquisition unit, an electric leakage protection unit, a driving unit and a control unit; a primary winding of the zero-sequence current transformer is used for connecting a main loop in the circuit breaking device, two secondary windings of the zero-sequence current transformer are connected with the first leakage current acquisition unit and the second leakage current acquisition unit respectively, the first leakage current acquisition unit is connected with the control unit, and the second leakage current acquisition unit is connected with the input end of the leakage protection unit. The output end of the leakage protection unit and the control unit are further connected with the input end of the driving unit, and the output end of the driving unit is used for being connected with an action executing mechanism in the circuit breaking device. According to the leakage protection circuit, the switching of the leakage function can be realized while leakage detection is carried out.

Description

Technical Field

[0001] The utility model relates to the technical field of integrated circuits, and in particular to a leakage protection circuit and a circuit breaker. Background Art

[0002] With the market demand for intelligent small circuit breakers, intelligent leakage products are widely used in residential, commercial, industrial and other fields due to their features such as remote control, data upload, timely alarm, and protection reporting.

[0003] Since there are currently no specific standards for small intelligent leakage circuit breakers, there are many different types of intelligent leakage circuit breakers on the market, each implementing different standards. Consequently, different manufacturers have different understandings of leakage detection in these intelligent products. Currently, small intelligent leakage circuit breakers on the market primarily use integrated leakage detection chips to determine leakage and trigger the circuit breaker, meeting the requirements for rapid leakage detection and short-term operation.

[0004] However, the use of an integrated leakage current chip will make the intelligent leakage current function incomplete, and it will not be possible to implement actions such as enabling and disabling the leakage current function and modifying the leakage current value while detecting the leakage current. Utility Model Content

[0005] The purpose of the utility model is to provide a leakage protection circuit and a circuit breaker, which can detect leakage and realize the activation and deactivation of the leakage function.

[0006] An embodiment of the utility model provides a leakage protection circuit, which includes: a zero-sequence current transformer, a first leakage current acquisition unit, a second leakage current acquisition unit, a leakage protection unit, a driving unit, and a control unit;

[0007] The primary winding of the zero-sequence current transformer is used to connect to the main circuit in the circuit breaker device. The two secondary windings of the zero-sequence current transformer are respectively connected to the first leakage current acquisition unit and the second leakage current acquisition unit. The first leakage current acquisition unit is connected to the control unit, and the second leakage current acquisition unit is connected to the input end of the leakage protection unit. The output end of the leakage protection unit and the control unit are also connected to the input end of the drive unit. The output end of the drive unit is used to connect to the action execution mechanism in the circuit breaker device.

[0008] Optionally, the leakage protection circuit further includes: a first coupling unit and a second coupling unit, wherein a first end of the first coupling unit is used to connect to a first preset power supply, a second end of the first coupling unit is connected to the control unit, a third end of the first coupling unit is grounded, and a fourth end of the first coupling unit is connected to the input end of the driving unit;

[0009] The first end of the second coupling unit is connected to the output end of the driving unit, the second end of the second coupling unit is used to connect to the action execution mechanism, the third end of the second coupling unit is used to connect to the first preset power supply, and the fourth end of the second coupling unit is connected to the control unit.

[0010] Optionally, the leakage protection circuit further includes: a leakage current gear switching unit, and the control unit is connected to the second leakage current collection unit via the leakage current gear switching unit.

[0011] Optionally, the leakage current gear switching unit includes: a gear switching switch unit, at least one input end of the gear switching switch unit is the input end of the leakage current gear switching unit, both of which are used to connect to the control unit, at least one normally closed end of the gear switching switch unit is connected to the first input end of the second leakage current collection unit, at least one normally open end of the gear switching switch unit is connected to the second input end of the second leakage current collection unit, and at least one common end of the gear switching switch unit is connected to the gear control end of the second leakage current collection unit.

[0012] Optionally, the gear switching switch unit is a switch unit having two groups of switch paths, the two input ends of the gear switching switch unit are the two input ends of the leakage current gear switching unit, both of which are used to connect to the control unit, the two normally closed ends of the gear switching switch unit are connected to the first input end of the second leakage current collection unit, the two normally open ends of the gear switching switch unit are connected to the second input end of the second leakage current collection unit, and the two common ends of the gear switching switch unit are connected to the two gear control ends of the second leakage current collection unit.

[0013] Optionally, the gear switching switch unit is an electronic analog switch chip integrated with two groups of switch paths; or, the gear switching switch unit includes: two independently set switch units.

[0014] Optionally, the second leakage current collection unit includes: a voltage-dividing resistor, a first resistor, a second resistor and a third resistor, the two ends of the voltage-dividing resistor are respectively the first input end and the second input end of the second leakage current collection unit, one end of the first resistor is connected to the first input end of the second leakage current collection unit, the voltage-dividing point of the voltage-dividing resistor and the other end of the first resistor are respectively the two gear control ends of the second leakage current collection unit; the two ends of the voltage-dividing resistor are respectively connected to one end of the second resistor and the third resistor, the other ends of the second resistor and the third resistor are the output ends of the second leakage current collection unit, which are used to connect to the input end of the leakage protection unit.

[0015] Optionally, the leakage protection circuit further includes: at least one third coupling unit;

[0016] The first end of at least one of the third coupling units is used to connect to the first preset power supply, the second end of at least one of the third coupling units is connected to the control unit, the fourth end of at least one of the third coupling units is used to connect to the second preset power supply, and the third end of at least one of the third coupling units is connected to at least one input end of the gear switching switch unit.

[0017] Optionally, the leakage protection circuit further includes: a dip switch, wherein the dip switch is connected to the leakage current gear switching unit.

[0018] Another embodiment of the present invention provides a circuit breaker device, which at least includes: any one of the above-mentioned leakage protection circuits and an action execution mechanism, wherein the leakage protection circuit is connected to the action execution mechanism.

[0019] The beneficial effects of the leakage protection circuit and the circuit breaker provided by the utility model are:

[0020] The control unit in the present application is connected to the leakage protection unit. When the leakage protection unit outputs a high level, the signal output by the leakage protection unit can be pulled down by the control unit, so that the drive unit cannot be driven, and thus the actuator cannot be driven to perform the corresponding action. In other words, the leakage protection circuit can be controlled in the present application to realize the leakage function can be put into and out of operation while detecting the leakage current. It can be realized that when leakage occurs, the leakage protection unit is connected to the drive circuit to drive the action execution structure. It can also be controlled by the control unit to make the leakage protection unit invalid when the leakage function is not needed, and the leakage protection unit cannot be connected to the drive circuit to drive the action execution structure. Thereby, the diversity of the leakage protection circuit function is improved, the fault power outage time caused by leakage is reduced, and the automatic control of the leakage protection circuit is realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 A schematic structural diagram of a first leakage protection circuit provided in an embodiment of the present application;

[0023] Figure 2 A schematic structural diagram of a second leakage protection circuit provided in an embodiment of the present application;

[0024] Figure 3 A schematic structural diagram of a third leakage protection circuit provided in an embodiment of the present application;

[0025] Figure 4 A schematic structural diagram of a fourth leakage protection circuit provided in an embodiment of the present application;

[0026] Figure 5 A schematic structural diagram of a fifth leakage protection circuit provided in an embodiment of the present application;

[0027] Figure 6 A schematic structural diagram of a sixth leakage protection circuit provided in an embodiment of the present application;

[0028] Figure 7 A schematic structural diagram of a seventh leakage protection circuit provided in an embodiment of the present application;

[0029] Figure 8 A schematic structural diagram of an eighth leakage protection circuit provided in an embodiment of the present application;

[0030] Figure 9 A schematic structural diagram of a ninth leakage protection circuit provided in an embodiment of the present application;

[0031] Figure 10 A schematic structural diagram of a tenth leakage protection circuit provided in an embodiment of the present application;

[0032] Figure 11 A schematic structural diagram of a circuit breaker device provided in an embodiment of the present application.

[0033] Icons: leakage protection circuit-1000; zero-sequence current transformer-100; first leakage current acquisition unit-200; second leakage current acquisition unit-300; leakage protection unit-400; drive unit-500; control unit-600; action execution mechanism-700; leakage current gear switching unit-800; gear switching unit-801; voltage divider resistor-R; first resistor-R1; second resistor-R2; third resistor-R3; first coupling unit-U1; second coupling unit-U2; third coupling unit-U3. DETAILED DESCRIPTION

[0034] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0035] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are also within the scope of protection of the present invention.

[0036] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0037] In the description of the present invention, it should be understood that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, or are the orientation or position relationship in which the utility model product is usually placed when in use, or are the orientation or position relationship commonly understood by those skilled in the art. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0038] Furthermore, the terms “first,” “second,” “third,” etc., are merely used for distinguishing descriptions and are not to be understood as indicating or implying relative importance.

[0039] It should also be noted that, in the description of this utility model, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0040] To clearly describe a leakage protection circuit provided by an embodiment of the present application, a leakage protection circuit provided by an embodiment of the present application is described below with reference to a plurality of drawings. The embodiment of the present application provides a first leakage current protection circuit. Figure 1 This is a schematic diagram of the structure of the first leakage protection circuit provided in the embodiment of the present application, as shown in FIG. Figure 1 As shown, the leakage protection circuit includes: a zero-sequence current transformer 100, a first leakage current acquisition unit 200, a second leakage current acquisition unit 300, a leakage protection unit 400, a driving unit 500 and a control unit 600;

[0041] The primary winding of the zero-sequence current transformer 100 is used to connect to the main circuit in the circuit breaker device (not shown in the figure), and the two secondary windings of the zero-sequence current transformer 100 are respectively connected to the first leakage current collection unit 200 and the second leakage current collection unit 300. The first leakage current collection unit 200 is connected to the control unit 600, and the second leakage current collection unit 300 is connected to the input end of the leakage protection unit 400. The output end of the leakage protection unit 400 and the control unit 600 are also connected to the input end of the drive unit 500. The output end of the drive unit 500 is used to connect to the action actuator 700 in the circuit breaker device.

[0042] The zero-sequence current transformer 100 is used to detect the zero-sequence current in the main circuit of the circuit breaker. The vector sum of the three-phase currents in the main circuit of the circuit breaker is usually zero, that is, the three-phase currents are mutually balanced. When a fault or imbalance occurs, a zero-sequence current is generated, that is, the vector sum of the three-phase currents is no longer zero, in which case leakage protection is required. The zero-sequence current transformer 100 can be a dual-winding zero-sequence current transformer, which is respectively connected to the first leakage current collection unit 200 and the second leakage current collection unit 300. The zero-sequence current transformer 100 can also be a single-winding zero-sequence current transformer. In this case, the first leakage current collection unit 200 and the second leakage current collection unit 300 can be isolated by a transformer. One end of the zero-sequence current transformer 100 is connected to one end of the primary winding of the transformer, the other end of the primary winding of the transformer is connected to the first leakage current collection unit 200, and both ends of the secondary winding of the transformer are connected to the second leakage current collection unit 300.

[0043] The first leakage current acquisition unit 200 is used to amplify the current signal collected by the zero-sequence current transformer 100. The first leakage current acquisition unit 200 can be an operational amplifier. The leakage current signal collected by the zero-sequence current transformer 100 is amplified by the first leakage current acquisition unit 200 and sent to the control unit 600, so that the control unit 600 sends a drive signal to the drive unit 500 according to the leakage current signal, so that the drive unit 500 drives the action actuator 700.

[0044] The second leakage current acquisition unit 300 has a different structure from the first leakage current acquisition unit. The second leakage current acquisition unit 300 is used to convert a leakage current signal into a voltage signal.

[0045] For example, in this application, the leakage protection unit 400 can be a leakage chip, the model of which can be FM2147, and the driving unit 500 can be a driving chip, the model of which can be SGM48013XN5G / TR. In this application, the leakage protection unit 400 is described by taking the leakage chip and the leakage driving unit 500 by taking the driving chip as an example. Figure 2 A schematic diagram of the structure of the second leakage protection circuit provided in the embodiment of the present application is shown in FIG. Figure 2 As shown, the leakage protection chip includes a first input pin IN1, a second input pin IN2, a first negative power pin VSS-1, a second negative power pin VSS-2, a positive power pin VDD, an output pin OA, a delay pin DLY, and an action signal output pin OS. When the leakage protection chip detects that the leakage current at the first input pin IN1 and the second input pin IN2 exceeds a preset threshold, it issues an alarm via the indicator pin OS and triggers the disconnection of a circuit breaker or other protective device via the indicator pin OS. The delay pin DLY is used to set an appropriate delay time to avoid false triggering due to transient interference. The first negative power pin VSS-1, the second negative power pin VSS-2, and the positive power pin VDD provide the necessary power for the chip. The indicator pin OS is connected to the control unit 600 and is used to receive the control signal RCD_CONTROL output by the control unit 600.

[0046] Optionally, the leakage protection unit 400 may also include four capacitors. The delay pin DLY is grounded through the first capacitor to prevent false triggering and delay in action time due to transient interference or noise on the power line. The indication pin OA is grounded through the second capacitor, also to prevent false triggering due to transient interference or noise on the power line. The positive power pin VDD is connected to the second preset power supply and is grounded through the third capacitor and the fourth capacitor, wherein the second preset power supply is 5 volts, and the capacitance value of the fourth capacitor is greater than the capacitance value of the third capacitor. The positive power pin VDD is grounded through the third capacitor and the fourth capacitor to stabilize the power supply of the positive power pin VDD and reduce noise and ripple on the power line. The first negative power pin VSS-1 is grounded. The leakage protection unit 400 is used to amplify the voltage signal sent by the second leakage current acquisition unit 300, and then send a drive signal to the drive unit 500 according to the voltage signal, so that the drive unit 500 drives the action actuator 700.

[0047] The driver chip includes an input pin IN, a ground pin GND, a power pin VDD, a first output pin OUT1, and a second output pin OUT2. The input pin IN of the driver chip is used to connect to the output of the leakage protection unit, and the ground pin GND of the driver chip is grounded.

[0048] Optionally, the drive unit further includes a resistor, and the power pin VDD of the driver chip is connected to a third preset power supply via the resistor, wherein the voltage of the third preset power supply is 12 V. The first output pin OUT1 and the second output pin OUT2 of the driver chip are connected to the action actuator 700 in the circuit breaker device.

[0049] The action execution structure 700 is a tripper, and the action execution structure 700 receives the signal of the driving unit 500 to realize the tripping of the tripper.

[0050] Optionally, a switch unit is further connected between the drive unit 500 and the action actuator 700. The drive unit 500 can drive the switch unit to disconnect and connect. The switch unit can be an N-type field effect transistor, wherein the first end of the switch unit is the gate of the N-type field effect transistor, the second end of the switch unit is the source of the N-type field effect transistor, and the third end of the switch unit is the drain of the N-type field effect transistor.

[0051] For example, Figure 3 A schematic diagram of the structure of the third leakage protection circuit provided in the embodiment of the present application is shown as follows: Figure 3 As shown in the above Figure 2 On the basis of the invention, the leakage protection circuit further includes a switching unit. In the present application, the switching unit is an N-type field effect transistor as an example. The gate of the N-type field effect transistor is connected to the output end of the driving unit 500, the source of the N-type field effect transistor is grounded, and the drain of the N-type field effect transistor is connected to the action execution structure 700. The drain of the N-type field effect transistor is connected to a preset fourth preset power supply, which can be a rectified voltage, such as a strong current.

[0052] Optionally, the switch unit can also be connected to a fourth preset power supply via a diode, and the diode is used to protect the switch unit to prevent excessive voltage from breaking down the switch unit. The switch unit and the drive unit 500 can be connected via a light-emitting diode, and the light-emitting diode is used to determine whether a drive signal is generated. A parallel capacitor and resistor are also connected between the light-emitting diode and the switch unit, and one end of the parallel capacitor and resistor is connected to the first end of the switch unit, and the other end is connected to the third end of the switch unit. Two series-connected voltage-stabilizing diodes can also be connected between the second and third ends of the switch unit to protect the switch unit.

[0053] Optionally, the control unit 600 outputs a low level to the drive unit and the leakage protection unit 400. At this time, the leakage current is sent to the leakage protection unit 400 through the zero-sequence current transformer 100. When the leakage current is greater than a preset threshold, the leakage delay flag is set and the fault timing is performed. When the fault time exceeds the preset time threshold, the leakage protection unit 400 outputs a high level to the drive unit, driving the action execution mechanism 700 in the circuit breaker device to perform the corresponding action.

[0054] The present application provides a leakage protection circuit, which includes: a zero-sequence current transformer, a first leakage current collection unit, a second leakage current collection unit, a leakage protection unit, a drive unit and a control unit; the primary winding of the zero-sequence current transformer is used to connect to the main circuit in the circuit breaker device, and the two secondary windings of the zero-sequence current transformer are respectively connected to the first leakage current collection unit and the second leakage current collection unit, the first leakage current collection unit is connected to the control unit, and the second leakage current collection unit is connected to the input end of the leakage protection unit, the output end of the leakage protection unit and the control unit are also connected to the input end of the drive unit, and the output end of the drive unit is used to connect to the action execution mechanism in the circuit breaker device. The leakage condition in the main circuit of the circuit breaker is detected by a zero-sequence current transformer, and the collected leakage current signal is sent to the first leakage current and the second leakage current collection unit respectively. The first leakage current collection unit sends the leakage current signal to the control unit, and the second leakage current collection power supply converts the leakage current signal into a voltage signal and sends it to the leakage protection unit. The leakage protection unit amplifies the input voltage signal. When the voltage signal exceeds the preset threshold, it indicates that the main circuit of the circuit breaker is leaking, and outputs a high level to the drive unit, so that the drive unit drives the action execution mechanism to perform the corresponding action. The control unit in this application is connected to the leakage protection unit. When the leakage protection unit outputs a high level, the signal output by the leakage protection unit can be pulled down by the control unit, so that the drive unit cannot be driven, thereby failing to drive the actuator to perform the corresponding action. In other words, the leakage protection circuit can be controlled to be retractable in this application. It can be realized that when leakage occurs, the action execution structure is connected to the leakage protection unit and the drive circuit, and when the leakage function is not needed, the leakage protection unit can be controlled to fail by the control unit, so that the action execution structure cannot be connected to the leakage protection unit and the drive circuit. This improves the diversity of the leakage protection circuit's functions, reduces the power outage time caused by leakage, and realizes automated control of the leakage protection circuit.

[0055] On the basis of the above embodiment, the leakage protection circuit further includes: a first coupling unit and a second coupling unit. The embodiment of the present application provides a fourth leakage current protection circuit, Figure 4 A schematic diagram of the structure of the fourth leakage protection circuit provided in the embodiment of the present application is shown as follows: Figure 4 As shown in the above Figure 2 On the basis of, the leakage protection circuit further includes: a first coupling unit U1 and a second coupling unit U2, a first end of the first coupling unit U1 is used to connect to the first preset power supply V1, a second end of the first coupling unit U1 is connected to the control unit 600, a third end of the first coupling unit U1 is grounded, and a fourth end of the first coupling unit U1 is connected to the input end of the driving unit 500;

[0056] The first end of the second coupling unit U2 is connected to the output end of the driving unit 500, the second end of the second coupling unit U2 is used to connect to the action execution mechanism 700, the third end of the second coupling unit U2 is used to connect to the first preset power supply V1, and the fourth end of the second coupling unit U2 is connected to the control unit.

[0057] The first coupling unit U1 and the second coupling unit U2 can be isolation units such as an isolation transformer, a relay, or a photoelectric coupler. The schematic diagram of this application uses a photoelectric coupler as an example. The photoelectric coupler includes a light-emitting diode and an isolation medium. The first preset power supply V1 is a 3.3 negative power supply. The first coupling unit U1 is used to isolate the input signal of the control unit 600 from the signal received by the drive unit 500. The first end of the first coupling unit U1 is the positive electrode of the light-emitting diode connected to the first preset power supply V1, the second end of the first coupling unit U1 is the negative electrode of the light-emitting diode connected to the control unit 600, the third end of the first coupling unit U1 is one end of the isolation medium connected to ground, and the fourth end of the first coupling unit U1 is the other end of the isolation medium connected to the input end of the drive unit 500. When the control unit 600 inputs a high level, the drive unit 500 receives the high level. When the control unit 600 inputs a low level, the drive unit 500 receives the low level.

[0058] Optionally, a capacitor-resistor circuit is further connected in parallel to the first end of the first coupling unit U1 and the second end of the first coupling unit U1. One end of the capacitor-resistor circuit is connected to the first end of the first coupling unit U1 and the first preset power supply, and one end of the capacitor-resistor circuit is connected to the second end of the first coupling unit U1 and the control unit 600. The capacitor-resistor circuit is used to filter noise and interference signals in the circuit.

[0059] The second coupling unit U2 is used to isolate the input signal of the drive unit 500 from the signal received by the control unit 600. The first end of the second coupling unit U2 is the positive electrode of the light-emitting diode, which is used to connect to the output of the drive unit 500. The second end of the second coupling unit U2 is the negative electrode of the light-emitting diode, which is used to connect to the action actuator 700. The third end of the second coupling unit U2 is one end of the isolation medium, which is used to connect to the control unit 600, so that the control unit 600 receives the feedback signal RCD_DEC from the drive unit 500. The fourth end of the second coupling unit U2 is the other end of the isolation medium, which is used to connect to the first preset power supply V1.

[0060] Optionally, a capacitor-resistor circuit is further connected in parallel to the third terminal of the second coupling unit U2 and the fourth terminal of the second coupling unit U2. One end of the capacitor-resistor circuit is connected to the third terminal of the second coupling unit U2 and the control unit 600, and one end of the capacitor-resistor circuit is connected to the fourth terminal of the second coupling unit U2 and the first preset power supply. The capacitor-resistor circuit is used to filter noise and interference signals in the circuit. The third terminal of the second coupling unit U2 is grounded via a resistor.

[0061] In the embodiment of the present application, isolation between different power supply systems can be achieved by setting up a first coupling unit and a second coupling unit, thereby preventing the influence of voltage fluctuations between different power supply systems and improving the stability and reliability of the leakage protection circuit.

[0062] On the basis of the above embodiment, the leakage protection circuit further includes: a leakage current gear switching unit. The present application embodiment provides a fifth leakage current protection circuit, Figure 5 A schematic diagram of the structure of the fifth leakage protection circuit provided in the embodiment of the present application is shown as follows: Figure 5 As shown in the above Figure 2 On the basis of, the leakage protection circuit further includes: a leakage current gear switching unit 800, and the control unit 600 is connected to the second leakage current collection unit 300 through the leakage current gear switching unit 800.

[0063] The leakage current gear switching unit 800 is used to switch the leakage current value in the leakage protection circuit to improve the flexibility of the leakage protection circuit.

[0064] On the basis of the above embodiment, the leakage current gear switching unit includes: a gear switching switch unit. The embodiment of the present application provides a sixth leakage current protection circuit, Figure 6 A schematic diagram of the structure of the sixth leakage protection circuit provided in the embodiment of the present application is shown in FIG. Figure 6 As shown in the above Figure 5 On the basis of, the leakage current gear switching unit 800 also includes: a gear switching switch unit 801, at least one input terminal IN of the gear switching switch unit 801 is the input terminal of the leakage current gear switching unit 800, both of which are used to connect to the control unit 600, at least one normally closed terminal NC of the gear switching switch unit 801 is connected to the first input terminal CT1 of the second leakage current collection unit 300, at least one normally open terminal NO of the gear switching switch unit 801 is connected to the second input terminal CT2 of the second leakage current collection unit 300, and at least one common terminal COM of the gear switching switch unit 801 is connected to the gear control terminal of the second leakage current collection unit 300.

[0065] The gear switching unit 801 is an electronic analog switch chip integrated with two sets of switch paths; alternatively, the gear switching unit includes two independently arranged switch units. The normally closed terminal NC of the gear switching unit 801 is connected to the common terminal COM when there is no control signal, allowing current to pass. When the control signal is activated, the normally closed terminal NC is disconnected from the common terminal COM. The normally open terminal NO of the gear switching unit 801 is disconnected from the common terminal COM when there is no control signal, preventing current from passing. When the control signal is activated, the normally open terminal NO is connected to the common terminal COM, allowing current to pass. The input terminal IN of the gear switching unit 801 is used to receive the control signal and control the state of the gear switching unit.

[0066] Optionally, the gear switching switch unit 801 further includes a power supply terminal V+ and a ground terminal GND. The power supply terminal V+ of the gear switching switch unit 801 is connected to a second preset power supply, and the voltage of the second preset power supply is 5 V. The input terminal IN of the gear switching switch unit 801 can also be grounded through a resistor.

[0067] In an embodiment of the present application, the flexibility of the leakage protection circuit can be improved by setting a leakage current gear switching unit, and a suitable leakage protection threshold can be selected according to actual needs. It is not possible to set multiple leakage protection circuits to achieve different leakage current detection, thereby saving circuit costs.

[0068] Based on the above embodiments, the present invention provides a sixth leakage current protection circuit. Figure 6 A schematic diagram of the structure of the seventh leakage protection circuit provided in the embodiment of the present application is shown in FIG. Figure 7 As shown in the above Figure 7 On the basis of, the gear switching switch unit 801 is a switch unit with two groups of switch paths. In this application, the gear switching switch unit 801 is explained by taking an electronic analog switch chip integrating two groups of switch paths as an example. The two input terminals IN1 and IN2 of the gear switching switch unit 801 are the two input terminals of the leakage current gear switching unit 800, both of which are used to connect the control unit 600. The two normally closed terminals NC1 and NC2 of the gear switching switch unit 801 are connected to the first input terminal CT1 of the second leakage current collection unit 300, the two normally open terminals NO1 and NO2 of the gear switching switch unit 801 are connected to the second input terminal CT2 of the second leakage current collection unit 300, and the two common terminals COM1 and COM2 of the gear switching switch unit 801 are connected to the two gear control terminals of the second leakage current collection unit 300.

[0069] Among them, the gear switching switch unit 801 is a switch unit with two groups of switch paths, that is, the gear switching switch unit 801 in this application has two input terminals, two normally closed terminals, two normally open terminals, and two common terminals.

[0070] In an embodiment of the present application, the gear switching switch unit is a switch unit having two sets of switch paths, so that a variety of different leakage currents can be monitored in the leakage protection circuit, thereby improving the flexibility and practicality of the leakage protection circuit.

[0071] Based on the above embodiment, the second leakage current acquisition unit includes: a voltage divider resistor, a first resistor, a second resistor and a third resistor. This application also provides an eighth leakage protection circuit, Figure 8 The eighth leakage protection circuit provided in the embodiment of the present application is shown in FIG. Figure 8 As shown in the above Figure 6 On the basis of, the second leakage current collection unit includes: a voltage dividing resistor R, a first resistor R1, a second resistor R2 and a third resistor R3, the two ends of the voltage dividing resistor R are respectively the first input terminal CT1 and the second input terminal CT2 of the second leakage current collection unit 300, one end of the first resistor R1 is connected to the first input terminal CT1 of the second leakage current collection unit 300, the voltage dividing point of the voltage dividing resistor R and the other end of the first resistor R1 are respectively two gear control ends of the second leakage current collection unit 300; the two ends of the voltage dividing resistor R are respectively connected to one end of the second resistor R2 and the third resistor R3, the other ends of the second resistor R2 and the third resistor R3 are the output ends of the second current sampling unit 300, and are used to connect to the input end of the leakage protection unit 400.

[0072] The schematic diagram of this application uses two voltage-divider resistors as an example. Multiple voltage-divider resistors are also possible and are not limited in this embodiment. The specific number of voltage-divider resistors is determined based on actual needs. The other ends of the second resistor R2 and the third resistor R3 serve as the output terminals of the second current sampling unit 300, and the corresponding leakage protection unit 400 has two input terminals.

[0073] Optionally, when the first input terminal IN1 and the second input terminal IN2 of the gear switching switch unit 801 are set to low, the first common terminal COM1 and the second common terminal COM2 of the gear switching switch unit 801 are connected to the first normally closed terminal NC1 and the second normally closed terminal NC2 of the gear switching switch unit 801, respectively. In this case, the leakage current collection resistor in the second leakage current collection unit 300 is the resistor in the voltage divider resistor R connected to the first input terminal of the second leakage current collection unit 300. In this case, the rated residual current is IN1. An electrical signal is determined by the second resistor R2 and the third resistor R3, and the electrical signal is input to the input terminal of the leakage protection unit 400.

[0074] Optionally, when the first input terminal IN1 of the gear switch unit 801 is set low and the second input terminal IN2 is set high, the first common terminal COM1 of the gear switch unit 801 is connected to the first normally closed terminal NC1 of the gear switch unit 801, and the second common terminal COM2 of the gear switch unit 801 is connected to the second normally open terminal NO2 of the gear switch unit 801. In this case, the leakage current collection resistor in the second leakage current collection unit 300 is the resistor in the voltage divider resistor R connected to the second input terminal of the second leakage current collection unit 300, and the rated residual current is IN2. An electrical signal is determined by the second resistor R2 and the third resistor R3, and the electrical signal is input to the input terminal of the leakage protection unit 400.

[0075] Optionally, when the first input terminal IN1 of the gear switch unit 801 is set high and the second input terminal IN2 is set high, the first common terminal COM1 of the gear switch unit 801 is connected to the first normally-open terminal NO1 of the gear switch unit 801, and the second common terminal COM2 of the gear switch unit 801 is connected to the second normally-open terminal NO2 of the gear switch unit 801. In this case, the leakage current collection resistor in the second leakage current collection unit 300 is the first resistor R1, and the rated residual current is IN3. An electrical signal is determined by the resistance of the voltage divider resistor R connected to the first input terminal of the second leakage current collection unit 300, and the electrical signal is input to the input terminal of the leakage protection unit 400.

[0076] Optionally, the output end of the second current sampling unit 300 has two output ends, and the output end of the second current sampling unit 300 has two output ends respectively connected to the two input ends of the leakage protection unit 400. A low-pass filter circuit is connected between the output end of the second current sampling unit 300 and the two input ends of the leakage protection unit. The low-pass filter circuit is used to remove interference in the circuit. The low-pass filter circuit can be set with three capacitors. The first input end of the leakage protection unit 400 is connected to the third resistor R3 and is grounded through the first capacitor. The third resistor R3 is connected to the second resistor R2 through the second capacitor, and the second resistor R2 is grounded through the third capacitor.

[0077] Optionally, two light-emitting diodes are further connected in parallel between the first input terminal CT1 and the second input terminal CT2 of the second current sampling unit 300, wherein the anode of the first light-emitting diode is connected to the first input terminal CT1, and the cathode of the first light-emitting diode is connected to the second input terminal CT2, the anode of the second light-emitting diode is connected to the second input terminal CT2, and the cathode of the second light-emitting diode is connected to the first input terminal CT1, and the current direction between the first input terminal CT1 and the second input terminal CT2 is determined by the light emission of the two diodes.

[0078] In an embodiment of the present application, by controlling the input of the gear switching switch unit, the on-off condition inside the gear switching switch unit is changed, thereby changing the loop resistance in the corresponding second leakage current acquisition unit, and determining the corresponding voltage signal through the voltage divider resistor, so that the leakage protection circuit can detect different leakage currents, thereby improving the practicality of the leakage protection circuit.

[0079] Based on the above embodiment, the leakage protection circuit further includes: at least one third coupling unit. The present application also provides a ninth leakage protection circuit, Figure 9 A ninth leakage protection circuit according to an embodiment of the present invention is shown in FIG. Figure 9 As shown in the above Figure 6 On the basis of this, the leakage protection circuit also includes: at least one third coupling unit U3; the first end of at least one third coupling unit U3 is used to connect to the first preset power supply V1, the second end of at least one third coupling unit U3 is connected to the control unit 600, the fourth end of at least one third coupling unit U3 is used to connect to the second preset power supply V2, and the third end of at least one third coupling unit U3 is connected to at least one input end of the gear switching switch unit 800.

[0080] Optionally, the present application takes a third coupling unit U3 as an example, the third coupling unit U3 is a photoelectric coupler, the first end of the third coupling unit U3 is the positive pole of the light-emitting diode used to connect to the first preset power supply V1, the second end of the third coupling unit U3 is the negative pole of the light-emitting diode connected to the control unit 600, the fourth end of the third coupling unit U3 is one end of the isolation medium used to connect to the second preset power supply V2, and the third end of the third coupling unit U3 is the other end of the isolation medium connected to an input end of the gear switching switch unit 800.

[0081] Optionally, a capacitor-resistor circuit is further connected in parallel to the first end of the third coupling unit U3 and the second end of the third coupling unit U3. One end of the capacitor-resistor circuit is connected to the second end of the third coupling unit U3 and the control unit 600, and one end of the capacitor-resistor circuit is connected to the first end of the third coupling unit U3 and the first preset power supply. The capacitor-resistor circuit is used to filter noise and interference signals in the circuit.

[0082] In the embodiment of the present application, isolation between different power supply systems can be achieved by setting up a third coupling unit, thereby preventing the influence of voltage fluctuations between different power supply systems and improving the stability and reliability of the leakage protection circuit.

[0083] On the basis of the above embodiment, the leakage protection circuit further includes: a dial switch. This application also provides a tenth leakage protection circuit, Figure 10 A schematic diagram of the structure of the tenth leakage protection circuit provided in the embodiment of the present application is shown as follows: Figure 10 As shown in the above Figure 1 On the basis of, the leakage protection circuit further includes: a dip switch 900, and the dip switch 900 is connected to the second leakage current collection unit 300.

[0084] Among them, the dip switch 900 can be a knob switch, each normally open switch and each normally closed switch of the knob switch are connected to multiple leakage current collection resistors in the second leakage current collection unit, and the adjustment of the detected leakage current is achieved by switching the normally open and normally closed switches of the knob switch to the first input end and the second input end of the second leakage current collection unit 300.

[0085] Optionally, each normally open switch and each normally closed switch of the DIP switch 900 are connected to multiple leakage current collection resistors, and different leakage currents can be collected by adjusting the DIP switch 900. Accordingly, the second leakage current collection unit does not need to be equipped with a leakage current collection resistor; it only needs to be equipped with a resistor in the circuit connecting the output terminal of the second leakage current collection unit and the leakage protection unit.

[0086] In an embodiment of the present application, a dip switch is set, and the dip switch is connected to a second leakage current acquisition unit, so that the detected leakage current can be manually adjusted without opening the circuit board or using complex electronic equipment. The dip switch can be used without power supply, thereby increasing the reliability and flexibility of the leakage protection circuit.

[0087] Another embodiment of the present application further provides a circuit breaker device, Figure 11 A schematic diagram of the structure of a circuit breaker device provided in an embodiment of the present application is shown in FIG. Figure 11 As shown, the circuit breaker device includes: a leakage protection circuit 1000 and an action execution mechanism 700, and the leakage protection circuit 1000 is connected to the action execution mechanism 700.

[0088] Optionally, the circuit breaker device may further include a communication unit, which is connected to the control unit in the leakage protection circuit 1000 . A host computer or other device communicates with the leakage protection circuit 1000 through the communication unit to control the leakage protection circuit 1000 .

[0089] Optionally, the circuit breaker device may further include a storage unit, and the communication unit is connected to the control unit in the leakage protection circuit 1000 to store leakage fault records.

[0090] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A leakage protection circuit, characterized in that: The leakage protection circuit includes: a zero-sequence current transformer, a first leakage current acquisition unit, a second leakage current acquisition unit, a leakage protection unit, a driving unit and a control unit; The primary winding of the zero-sequence current transformer is used to connect to the main circuit in the circuit breaker device. The two secondary windings of the zero-sequence current transformer are respectively connected to the first leakage current acquisition unit and the second leakage current acquisition unit. The first leakage current acquisition unit is connected to the control unit, and the second leakage current acquisition unit is connected to the input end of the leakage protection unit. The output end of the leakage protection unit and the control unit are also connected to the input end of the drive unit. The output end of the drive unit is used to connect to the action execution mechanism in the circuit breaker device.

2. The leakage protection circuit according to claim 1, characterized in that: The leakage protection circuit further includes: a first coupling unit and a second coupling unit, wherein a first end of the first coupling unit is used to connect to a first preset power supply, a second end of the first coupling unit is connected to the control unit, a third end of the first coupling unit is grounded, and a fourth end of the first coupling unit is connected to the input end of the driving unit; The first end of the second coupling unit is connected to the output end of the driving unit, the second end of the second coupling unit is used to connect to the action execution mechanism, the third end of the second coupling unit is used to connect to the first preset power supply, and the fourth end of the second coupling unit is connected to the control unit.

3. The leakage protection circuit according to claim 1, characterized in that: The leakage protection circuit further includes: a leakage current gear switching unit, and the control unit is connected to the second leakage current acquisition unit via the leakage current gear switching unit.

4. The leakage protection circuit according to claim 3, characterized in that: The leakage current gear switching unit includes: a gear switching switch unit, at least one input end of the gear switching switch unit is the input end of the leakage current gear switching unit, both of which are used to connect to the control unit, at least one normally closed end of the gear switching switch unit is connected to the first input end of the second leakage current collection unit, at least one normally open end of the gear switching switch unit is connected to the second input end of the second leakage current collection unit, and at least one common end of the gear switching switch unit is connected to the gear control end of the second leakage current collection unit.

5. The leakage protection circuit according to claim 4, characterized in that: The gear switching switch unit is a switch unit having two groups of switch paths. The two input ends of the gear switching switch unit are the two input ends of the leakage current gear switching unit, both of which are used to connect to the control unit. The two normally closed ends of the gear switching switch unit are connected to the first input end of the second leakage current collection unit, the two normally open ends of the gear switching switch unit are connected to the second input end of the second leakage current collection unit, and the two common ends of the gear switching switch unit are connected to the two gear control ends of the second leakage current collection unit.

6. The leakage protection circuit according to claim 4, characterized in that: The gear shift switch unit is an electronic analog switch chip integrated with two groups of switch paths; or, the gear shift switch unit includes: two independently arranged switch units.

7. The leakage protection circuit according to claim 5, characterized in that: The second leakage current collection unit includes: a voltage-dividing resistor, a first resistor, a second resistor, and a third resistor. The two ends of the voltage-dividing resistor are respectively the first input end and the second input end of the second leakage current collection unit, one end of the first resistor is connected to the first input end of the second leakage current collection unit, and the voltage dividing point of the voltage-dividing resistor and the other end of the first resistor are respectively two gear control ends of the second leakage current collection unit; the two ends of the voltage-dividing resistor are respectively connected to one end of the second resistor and the third resistor, and the other ends of the second resistor and the third resistor are the output end of the second leakage current collection unit, which is used to be connected to the input end of the leakage protection unit.

8. The leakage protection circuit according to claim 4, characterized in that: The leakage protection circuit further includes: at least one third coupling unit; The first end of at least one of the third coupling units is used to connect to the first preset power supply, the second end of at least one of the third coupling units is connected to the control unit, the fourth end of at least one of the third coupling units is used to connect to the second preset power supply, and the third end of at least one of the third coupling units is connected to at least one input end of the gear switching switch unit.

9. The leakage protection circuit according to claim 1, characterized in that: The leakage protection circuit further includes: a dip switch, and the dip switch is connected to the second leakage current collection unit.

10. A circuit breaker device, characterized in that: The circuit breaker device at least comprises: the leakage protection circuit according to any one of claims 1 to 9 and an action execution mechanism, wherein the leakage protection circuit is connected to the action execution mechanism.

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