Circuit breaker leading-out terminal live detection circuit and circuit breaker

Abstract

The utility model discloses a live detection circuit for a wire outlet end of a circuit breaker. The live detection circuit comprises a controller, an optical coupler isolation circuit, a three-phase rectification circuit and a three-phase current limiting circuit, one end of the controller is respectively connected with phase poles A, B, C and N of wire inlet ends of the circuit breaker, the other end of the controller is respectively connected with the optocoupler isolation circuit, the optocoupler isolation circuit is connected with the three-phase rectification circuit, the three-phase rectification circuit is connected with the three-phase current limiting circuit, and the three-phase current limiting circuit is connected with phase poles A, B and C of wire outlet ends of the circuit breaker. The utility model also discloses a circuit breaker. According to the utility model, the technical problems that the existing circuit breaker cannot realize isolation, is complex in structure and is easily interfered are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit breakers, in particular to a live detection circuit for the outgoing line end of a circuit breaker and a circuit breaker. Background Art

[0002] A circuit breaker is a switching device that can close, carry, and break the current under normal circuit conditions and can also close, carry, and break the current under abnormal circuit conditions within a specified time. Circuit breakers can be divided into high-voltage circuit breakers and low-voltage circuit breakers according to their application scope. As a device for isolating and protecting electricity, the circuit breaker plays a key role in the power distribution system. When the circuit breaker is disconnected, it is necessary to confirm whether the outgoing line end is live. The traditional method is generally to detect the voltage situation of the outgoing line end by connecting to the A, B, C, and N phase poles of the outgoing line end. Since the voltage monitoring of the incoming line end of the circuit breaker also requires access to the N line, the isolation function fails. The patent document with the application number 201310566965.2 discloses a load line fault detection circuit and method applied to circuit breaker reclosing, including a detection circuit: connected to the load line to detect the load line; the detection circuit includes a short-circuit detection circuit and a leakage detection circuit, which are respectively used to detect the short-circuit fault and leakage fault of the load line; a controller: connected to the detection circuit and the circuit breaker respectively, and controlling the detection circuit to detect the load line before the circuit breaker is closed. Therefore, there is an urgent need to propose a live detection circuit for the outgoing line end of a circuit breaker and a circuit breaker to solve the technical problems that the existing circuit breaker cannot achieve isolation, has a complex structure, and is easily interfered. Summary of the Utility Model

[0003] The main purpose of the utility model is to propose a live detection circuit for the outgoing line end of a circuit breaker and a circuit breaker, aiming to solve the technical problems that the existing circuit breaker cannot achieve isolation, has a complex structure, and is easily interfered.

[0004] To achieve the above object, the utility model provides a live detection circuit for the outgoing line end of a circuit breaker and a circuit breaker, wherein the live detection circuit for the outgoing line end of the circuit breaker includes:

[0005] A controller, an opto-isolation circuit, a three-phase rectification circuit, and a three-phase current-limiting circuit;

[0006] One end of the controller is respectively connected to the incoming line end A, B, C, and N phase poles of the circuit breaker, the other end of the controller is respectively connected to the opto-isolation circuit, the opto-isolation circuit is connected to the three-phase rectification circuit, the three-phase rectification circuit is connected to the three-phase current-limiting circuit, and the three-phase current-limiting circuit is connected to the outgoing line end A, B, and C phase poles of the circuit breaker.

[0007] One of the preferred solutions is that the three-phase current-limiting circuit includes an A-phase current-limiting circuit;

[0008] The A-phase current-limiting circuit includes a resistor R1. One end of the resistor R1 is connected to the A-phase terminal of the circuit breaker output, and the other end of the resistor R1 is connected to the three-phase rectifier circuit.

[0009] One of the preferred solutions is that the three-phase current-limiting circuit includes a B-phase current-limiting circuit;

[0010] The B-phase current-limiting circuit includes a resistor R2. One end of the resistor R2 is connected to the B-phase terminal of the circuit breaker output, and the other end of the resistor R2 is connected to the three-phase rectifier circuit.

[0011] One of the preferred solutions is that the three-phase current-limiting circuit includes a C-phase current-limiting circuit;

[0012] The C-phase current-limiting circuit includes a resistor R3. One end of the resistor R3 is connected to the C-phase terminal of the circuit breaker output, and the other end of the resistor R3 is connected to the three-phase rectifier circuit.

[0013] One of the preferred solutions is that the three-phase rectifier circuit includes an A-phase rectifier circuit;

[0014] The A-phase rectifier circuit includes diodes D1 and D2. The anode of diode D1 is connected to the A-phase current-limiting circuit and the cathode of diode D2, and the cathodes of diode D1 and the anode of diode D2 are both connected to the optocoupler isolation circuit.

[0015] One of the preferred solutions is that the three-phase rectifier circuit includes a B-phase rectifier circuit;

[0016] The B-phase rectifier circuit includes diodes D3 and D4. The anode of diode D3 is connected to the B-phase current-limiting circuit and the cathode of diode D4, and the cathodes of diode D3 and the anode of diode D4 are both connected to the optocoupler isolation circuit.

[0017] One of the preferred solutions is that the three-phase rectifier circuit includes a C-phase rectifier circuit;

[0018] The C-phase rectifier circuit includes diodes D5 and D6. The anode of diode D5 is connected to the C-phase current-limiting circuit and the cathode of diode D6, and the cathodes of diode D5 and the anode of diode D6 are both connected to the optocoupler isolation circuit.

[0019] One of the preferred solutions is that the optocoupler isolation circuit includes an optocoupler U1, a diode D7, and a resistor R4;

[0020] The 1-pin of the optocoupler U1 is respectively connected to the three-phase rectifier circuit and the cathode of the diode D7, the 2-pin of the optocoupler U1 is respectively connected to the three-phase rectifier circuit and the anode of the diode D7, the 3-pin of the optocoupler U1 is respectively connected to the resistor R4 and the controller, the other end of the resistor R4 is connected to the power supply terminal, and the 4-pin of the optocoupler U1 is grounded.

[0021] A circuit breaker, the circuit breaker including the live detection circuit at the outgoing line end of the circuit breaker described above.

[0022] In the above technical solution of the present utility model, the live detection circuit at the outgoing line end of the circuit breaker includes: a controller, an opto-isolation circuit, a three-phase rectification circuit, and a three-phase current-limiting circuit; one end of the controller is respectively connected to the incoming line ends A, B, C, and N phases of the circuit breaker, the other end of the controller is respectively connected to the opto-isolation circuit, the opto-isolation circuit is connected to the three-phase rectification circuit, the three-phase rectification circuit is connected to the three-phase current-limiting circuit, and the three-phase current-limiting circuit is connected to the outgoing line ends A, B, and C phases of the circuit breaker. The structure of the present utility model is simple and convenient to use, can effectively realize the isolation of the circuit breaker, and resist the interference between phases, solving the technical problems that the existing circuit breaker cannot achieve isolation, and has a complex structure and is easily interfered. Description of the Drawings

[0023] In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0024] Figure 1 It is a schematic structural diagram of a live detection circuit at the outgoing line end of a circuit breaker according to an embodiment of the present utility model;

[0025] Figure 2 It is a circuit diagram of a live detection circuit at the outgoing line end of a circuit breaker according to an embodiment of the present utility model.

[0026] The realization of the purpose, functional features, and advantages of the present utility model will be further described with reference to the drawings in combination with the embodiments. Specific Embodiments

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present utility model with reference to the drawings in the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, rather than all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present utility model.

[0028] In addition, in the present utility model, descriptions such as "first" and "second" are only for descriptive purposes and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature.

[0029] Moreover, the technical solutions between various embodiments of the present utility model can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0030] See Figure 1 - Figure 2 , according to one aspect of the present utility model, the present utility model provides a live detection circuit for the outlet terminal of a circuit breaker and a circuit breaker. Among them, the live detection circuit for the outlet terminal of the circuit breaker includes:

[0031] a controller, an optocoupler isolation circuit, a three-phase rectification circuit, and a three-phase current-limiting circuit;

[0032] One end of the controller is respectively connected to the incoming line terminals A, B, C, and N of the circuit breaker, the other end of the controller is respectively connected to the optocoupler isolation circuit, the optocoupler isolation circuit is connected to the three-phase rectification circuit, the three-phase rectification circuit is connected to the three-phase current-limiting circuit, and the three-phase current-limiting circuit is connected to the outlet terminal A, B, and C of the circuit breaker.

[0033] Specifically, in this embodiment, the three-phase current-limiting circuit includes a phase A current-limiting circuit; the phase A current-limiting circuit includes a resistor R1, one end of the resistor R1 is connected to the outlet terminal A of the circuit breaker, and the other end of the resistor R1 is connected to the three-phase rectification circuit.

[0034] Specifically, in this embodiment, the three-phase current-limiting circuit includes a phase B current-limiting circuit; the phase B current-limiting circuit includes a resistor R2, one end of the resistor R2 is connected to the outlet terminal B of the circuit breaker, and the other end of the resistor R2 is connected to the three-phase rectification circuit.

[0035] Specifically, in this embodiment, the three-phase current-limiting circuit includes a phase C current-limiting circuit; the phase C current-limiting circuit includes a resistor R3, one end of the resistor R3 is connected to the outlet terminal C of the circuit breaker, and the other end of the resistor R3 is connected to the three-phase rectification circuit.

[0036] Specifically, in this embodiment, the three-phase rectification circuit includes a phase A rectification circuit; the phase A rectification circuit includes a diode D1 and a diode D2; the anode of the diode D1 is connected to the resistor R1 of the phase A current-limiting circuit and the cathode of the diode D2, and the cathode of the diode D1 and the anode of the diode D2 are both connected to the optocoupler isolation circuit.

[0037] Specifically, in this embodiment, the three-phase rectifier circuit includes a B-phase rectifier circuit; the B-phase rectifier circuit includes diode D3 and diode D4; the anode of diode D3 is connected to resistor R2 of the B-phase current-limiting circuit and the cathode of diode D4, and the cathodes of diode D3 and the anode of diode D4 are both connected to the optocoupler isolation circuit.

[0038] Specifically, in this embodiment, the three-phase rectifier circuit includes a C-phase rectifier circuit; the C-phase rectifier circuit includes diode D5 and diode D6; the anode of diode D5 is connected to resistor R3 of the C-phase current-limiting circuit and the cathode of diode D6, and the cathodes of diode D5 and the anode of diode D6 are both connected to the optocoupler isolation circuit.

[0039] Specifically, in this embodiment, the optocoupler isolation circuit includes optocoupler U1, diode D7 and resistor R4; the 1-pin of optocoupler U1 is respectively connected to the three-phase rectifier circuit and the cathode of diode D7, the 2-pin of optocoupler U1 is respectively connected to the three-phase rectifier circuit and the anode of diode D7, the 3-pin of optocoupler U1 is respectively connected to resistor R4 and the controller, the other end of resistor R4 is connected to the power supply terminal, and the 4-pin of optocoupler U1 is grounded; in the present utility model, by reversely connecting diode D7 in parallel at the input end of optocoupler U1, it is used to protect the light-emitting diode at the input end of optocoupler U1, preventing the light-emitting diode of optocoupler U1 from being damaged when a reverse abnormal voltage appears, resulting in circuit failure.

[0040] Specifically, in this embodiment, the optocoupler U1 can adopt an optocoupler of model TLP785, and the diodes provided in the rectifier circuit and the optocoupler isolation circuit can adopt diodes of model SM520. The present utility model does not make specific limitations and can be specifically set according to needs.

[0041] Specifically, in this embodiment, the controller takes power and obtains voltage signals at the A, B, C, and N phase poles at the incoming line end of the circuit breaker. When any one or several phases at the outgoing line end are powered on, a loop is formed through the optocoupler isolation circuit, the three-phase rectifier circuit, and the three-phase current-limiting circuit. Thus, the light-emitting diode of optocoupler U1 conducts and lights up, the corresponding triode in optocoupler U1 conducts, and the output terminal level is pulled low. When the controller receives the low level, it detects that the outgoing line end is charged; when all three phases at the outgoing line end are not powered on, there is no voltage loop through the optocoupler isolation circuit, the three-phase rectifier circuit, and the three-phase current-limiting circuit. Thus, the light-emitting diode of optocoupler U1 goes out, the corresponding triode in optocoupler U1 is cut off, and the output terminal level is pulled high. When the controller receives the high level, it detects that the outgoing line end is powered off; since there is an optocoupler isolation circuit between the signal terminals of the A, B, and C phase lines and the N signal terminal of the circuit, a path cannot be formed between the phase and the ground. Therefore, it is not affected by the interference signal between the phase and the ground.

[0042] Specifically, in this embodiment, when abnormal surge voltages occur in the A, B, and C phase lines, for example, a positive surge voltage appears between the A-B phases, the surge voltage forms a path through the opto-isolation circuit, three-phase rectification circuit, and three-phase current-limiting circuit. Due to the current-limiting effect of the current-limiting resistors in the three-phase current-limiting circuit, the surge current will be limited to a very small range, preventing the diodes of the three-phase rectification circuit from being directly broken down by excessive surge current, thereby causing circuit damage; the utility model does not require diodes with a large current-carrying capacity in the three-phase rectification circuit, and at the same time, the phase-to-phase impulse withstand voltage capacity of the circuit can be improved by limiting the current.

[0043] According to another aspect of the present utility model, the present utility model provides a circuit breaker, wherein the circuit breaker includes the above-mentioned live detection circuit for the outlet end of the circuit breaker.

[0044] The above are only the preferred embodiments of the present utility model, and do not limit the patent scope of the present utility model. Any equivalent structural transformation made under the inventive concept of the present utility model by using the content of the specification and drawings of the present utility model, or direct / indirect application in other related technical fields, is included in the patent protection scope of the present utility model.

Claims

1. A circuit breaker outlet terminal live detection circuit, characterized in that: include: Controller, optocoupler isolation circuit, three-phase rectification circuit and three-phase current limiting circuit; One end of the controller is connected to the A, B, C, and N phase poles of the circuit breaker's incoming terminals respectively, and the other end of the controller is connected to the optocoupler isolation circuit respectively, the optocoupler isolation circuit is connected to the three-phase rectifier circuit, the three-phase rectifier circuit is connected to the three-phase current limiting circuit, and the three-phase current limiting circuit is connected to the A, B, and C phase poles of the circuit breaker's outgoing terminals.

2. A circuit breaker outlet terminal live detection circuit according to claim 1, characterized in that: The three-phase current limiting circuit includes an A-phase current limiting circuit; The A-phase current limiting circuit comprises a resistor R1, one end of the resistor R1 is connected to the A-phase pole of the circuit breaker outlet terminal, and the other end of the resistor R1 is connected to the three-phase rectifier circuit.

3. A circuit breaker outlet terminal live detection circuit according to any one of claims 1-2, characterized in that: The three-phase current limiting circuit includes a B-phase current limiting circuit; The B-phase current limiting circuit includes a resistor R2, one end of the resistor R2 is connected to the B-phase pole of the circuit breaker output terminal, and the other end of the resistor R2 is connected to the three-phase rectifier circuit.

4. A circuit breaker outlet terminal live detection circuit according to any one of claims 1-2, characterized in that: The three-phase current limiting circuit includes a C-phase current limiting circuit; The C-phase current limiting circuit includes a resistor R3, one end of the resistor R3 is connected to the C-phase pole of the circuit breaker outlet terminal, and the other end of the resistor R3 is connected to the three-phase rectifier circuit.

5. A circuit breaker outlet terminal live detection circuit according to claim 2, characterized in that: The three-phase rectifier circuit includes an A-phase rectifier circuit; The A-phase rectifier circuit includes a diode D1 and a diode D2; the anode of the diode D1 is connected to the A-phase current limiting circuit and the cathode of the diode D2, and the cathode of the diode D1 and the anode of the diode D2 are both connected to the optocoupler isolation circuit.

6. A circuit breaker outlet terminal live detection circuit according to claim 3, characterized in that: The three-phase rectifier circuit includes a B-phase rectifier circuit; The B-phase rectification circuit includes a diode D3 and a diode D4; the anode of the diode D3 is connected to the B-phase current limiting circuit and the cathode of the diode D4, and the cathode of the diode D3 and the anode of the diode D4 are both connected to the optocoupler isolation circuit.

7. A circuit breaker outlet terminal live detection circuit according to claim 4, characterized in that: The three-phase rectifier circuit includes a C-phase rectifier circuit; The C-phase rectification circuit includes a diode D5 and a diode D6; the anode of the diode D5 is connected to the C-phase current limiting circuit and the cathode of the diode D6, and the cathode of the diode D5 and the anode of the diode D6 are both connected to the optocoupler isolation circuit.

8. A circuit breaker outlet terminal live detection circuit according to any one of claims 1-2, characterized in that: The optocoupler isolation circuit includes an optocoupler U1, a diode D7 and a resistor R4; Pin 1 of the optocoupler U1 is respectively connected to the cathode of the three-phase rectifier circuit and the diode D7, pin 2 of the optocoupler U1 is respectively connected to the anode of the three-phase rectifier circuit and the diode D7, pin 3 of the optocoupler U1 is respectively connected to the resistor R4 and the controller, the other end of the resistor R4 is connected to the power supply end, and pin 4 of the optocoupler U1 is grounded.

9. A circuit breaker, characterized in that: The circuit breaker comprises a circuit breaker outlet terminal live detection circuit as described in any one of claims 1-8.

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