A circuit breaker and control method thereof

Abstract

The present invention discloses a circuit breaker and a control method thereof, which relates to the technical field of control switches, and is invented to solve the problem in the prior art that an LED lamp-starting circuit breaker is prone to malfunction and a black light appears during a power outage. The present invention discloses a circuit breaker, comprising a main circuit connected between an incoming terminal and an outgoing terminal, the main circuit circuit comprising a main contact, the main contact being connected to a first release, the first release being used to drive the main contact to disconnect, and characterized in that it also comprises a control unit, the control unit being connected to the first release, the control unit being used to obtain, when the main contact is closed, a characterization value of an effective current in the main circuit circuit and a duration of the characterization value of the effective current being greater than or equal to a set current, and if the duration reaches the set time, the first release is controlled to drive the main contact to disconnect; wherein, before the duration reaches the set time, the main contact remains in a closed state.

Description

Technical Field

[0001] The present invention relates to the technical field of control switches, and in particular to a circuit breaker and a control method thereof. Background Art

[0002] A circuit breaker is a switch device that can close, carry and interrupt the current under normal circuit conditions, and can close, carry and interrupt the current under abnormal circuit conditions within a specified time. For the connection circuit of LED (Light Emitting Diode) lamps, when the LED lamp is started, a very large peak current (also called spike current) will be generated. The peak current may even reach 35 times the rated current value of the circuit breaker, causing the circuit breaker to disconnect and affecting the normal opening of the lamp.

[0003] A circuit breaker release in the prior art uses a C-curve release and a D-curve release. Since the instantaneous tripping current of the C-curve release is 5-10In (In refers to the rated current of the release) and the instantaneous tripping current of the D-type release is 10-20In, the instantaneous tripping current of the C-curve release and the D-curve release is still smaller than the instantaneous peak current value of the LED lamp, resulting in the circuit breaker still malfunctioning and disconnecting.

[0004] In another type of circuit breaker, a delay accessory is added to be used in conjunction with the circuit breaker. When using this type of circuit breaker, the LED light will light up after a certain interval at startup, and if multiple power sources are used, there will also be a period of black light when the power is switched. Summary of the invention

[0005] The implementation of the present invention provides a circuit breaker and a control method thereof, which can solve the problem in the prior art that the circuit breaker is prone to malfunction when the LED lamp is started, resulting in a power outage and a black light.

[0006] To achieve the above object, the embodiments of the present invention adopt the following technical solutions:

[0007] A circuit breaker comprises a main circuit connected between an incoming terminal and an outgoing terminal, the main circuit comprising a main contact, the main contact being connected to a first release, the first release being used to drive the main contact to open, and a control unit being connected to the first release, the control unit being used to obtain, when the main contact is closed, a characterization value of an effective current in the main circuit and a duration for which the characterization value of the effective current is greater than or equal to a set current, and if the duration reaches a set time, controlling the first release to drive the main contact to open; wherein, before the duration reaches the set time, the main contact remains in a closed state.

[0008] Furthermore, the control unit includes a current transformer and a control module, the input end of the current transformer is connected to the main loop circuit, and the output end of the current transformer is connected to the control module and is used to output the induced current to the control module; the control module is used to obtain the effective current value of the induced current as a characterization value of the effective current in the main loop circuit; and when the effective current value of the induced current is greater than or greater than or equal to the set current and the duration reaches a set time, the first release is controlled to drive the main contact to disconnect.

[0009] Furthermore, the control unit further comprises an actuator, the actuator is connected to the first release, and the control module is specifically configured to control the first release through the actuator to drive the main contact to be disconnected.

[0010] Furthermore, the control module includes: a sampling submodule, which is used to sample the induced current of the current transformer to obtain multiple discrete current values; a processing submodule, which is used to calculate the corresponding effective current value of the induced current based on the multiple discrete current values, and obtain the duration that the effective current value of the induced current is greater than or equal to the set current, and issue a control instruction when the duration reaches the set time; a driving submodule, which controls the actuator to push the first release according to the control instruction to disconnect the main contact.

[0011] Furthermore, the actuator is an electromagnetic release.

[0012] Furthermore, the main contact is connected to an elastic member, the first release includes a first connecting rod fixedly connected to the main contact, a second connecting rod buckled with the end of the first connecting rod, and a driving rod fixedly connected to the second connecting rod, the electromagnetic release includes a first magnet and a second magnet, a push rod is connected to the first magnet, when the first magnet moves toward the second magnet, the push rod on the first magnet pushes the driving rod to move so that the first connecting rod is disengaged from the second connecting rod, and the elastic member drives the main contact and the first connecting rod back to the disconnected position.

[0013] Furthermore, it also includes a thermal release, which includes an electric heating element and a bimetallic strip. The electric heating element is connected in series in the main circuit. When the temperature of the electric heating element is high, the bimetallic strip is deformed and pushes the driving rod to move, so that the first connecting rod and the second connecting rod are disengaged, and the elastic member drives the main contact back to the disconnected position.

[0014] An embodiment of the present invention also includes a circuit breaker control method, which is used for the circuit breaker described in the above embodiment, and the control method includes the following steps: when the main contact is closed, obtaining a characterization value of the effective current in the main loop circuit, and a duration during which the characterization value of the effective current is greater than or equal to a set current; if the duration reaches the set time, controlling the first release to drive the main contact to disconnect; wherein, before the duration reaches the set time, the main contact remains in a closed state.

[0015] Furthermore, the step of obtaining a characterizing value of the effective current in the main loop circuit specifically includes: obtaining an effective current value of the induced current of the main loop circuit as the characterizing value of the effective current in the main loop circuit.

[0016] Furthermore, the step of obtaining the effective current value of the induced current of the main loop circuit as a characterization value of the effective current in the main loop circuit specifically includes: sampling the induced current of the main loop circuit to obtain a plurality of discrete current values; and calculating the corresponding effective current value of the induced current based on the plurality of discrete current values.

[0017] Further, when the control unit includes an actuator, the step of controlling the first release to drive the main contact to disconnect if the duration reaches a set time specifically includes: issuing a control instruction when the duration reaches a set time; and controlling the actuator to push the first release according to the control instruction to disconnect the main contact.

[0018] The circuit breaker and control method provided by the embodiment of the present invention obtain the characterization value of the effective current in the main circuit and the duration of the characterization value of the effective current being greater than or equal to the set current. If the duration reaches the set time, that is, the main circuit is in a short-circuit state, the first release is controlled to drive the main contact to disconnect; before the duration reaches the set time, if the main circuit is in a start-up state, the main contact remains in a closed state. Therefore, in the embodiment of the present invention, the circuit breaker will control the first release to disconnect only after the current value is large and it is judged to be a short-circuit fault, and when the current value is large and it is judged that the LED lamp is started, the control unit will not send a control signal to disconnect the first release, so the problem of the circuit breaker disconnecting due to the high instantaneous current value when the LED lamp is started can be avoided, so that the protection characteristics of the circuit breaker are highly matched with the start-up characteristics of the LED lamp; and the LED lamp starts faster, and there will be no long black light time. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a structural schematic diagram of a circuit breaker according to an embodiment of the present invention;

[0021] Figure 2 Schematic diagram of the composition of a control unit in a circuit breaker according to an embodiment of the present invention;

[0022] Figure 3 This is a working diagram of a control module in a circuit breaker according to an embodiment of the present invention;

[0023] Figure 4 This is a control flow chart of a circuit breaker according to an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element 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.

[0026] Reference Figure 1The circuit breaker of the embodiment of the present invention comprises a main circuit 3 connected between an incoming terminal 1 and an outgoing terminal 2, the main circuit 3 comprises a main contact 31, the main contact 31 is connected to a first release 4, and the first release 4 is used to drive the main contact 31 to open. The circuit breaker also comprises a control unit 5, the control unit 5 is connected to the first release 4, the control unit 5 is used to obtain, when the main contact 31 is closed, a characterization value of an effective current value in the main circuit 3 and a duration of time when the characterization value of the effective current is greater than or equal to a set current, and if the duration reaches the set time, the first release 4 is controlled to drive the main contact 31 to open; wherein, before the duration reaches the set time, the main contact 31 remains in a closed state.

[0027] The circuit breaker provided in the embodiment of the present invention, after the control unit 5 obtains the characterization value of the effective current in the main circuit 3 and the duration of the characterization value of the effective current being greater than or equal to the set current, if the duration reaches the set time, that is, the main circuit 3 is in a short-circuit state, the first release 4 is controlled to drive the main contact 31 to disconnect; before the duration reaches the set time, if the main circuit 3 is in a starting state, the main contact 31 remains in a closed state. Therefore, in the embodiment of the present invention, the circuit breaker will control the first release to disconnect only after the current value is large and it is judged to be a short-circuit fault, and when the current value is large and it is judged that the LED lamp is started, the control unit will not send a control signal to disconnect the first release, so the problem of the circuit breaker disconnecting due to the high instantaneous current value when the LED lamp is started can be avoided, so that the protection characteristics of the circuit breaker are highly matched with the starting characteristics of the LED lamp; and the LED lamp starts faster, and there will be no long black light time.

[0028] Optionally, the control unit 5 can simultaneously obtain the characterization value of the effective current in the main loop circuit 3 and the duration of time that the characterization value of the effective current is greater than or equal to the set current. Alternatively, the control unit 5 can also first obtain the characterization value of the effective current in the main loop circuit 3, and under the condition that the characterization value of the effective current is greater than or equal to the set current, obtain the duration of time that the characterization value of the effective current is greater than or equal to the set current.

[0029] It should be noted that the representative value of the effective current in the main loop circuit 3 can be the actual current value in the main loop circuit 3 or the induced current value. Figure 2In one embodiment of the present invention, the control unit 5 includes a current transformer and a control module, the input end of the current transformer is connected to the main loop circuit 3, the output end of the current transformer is connected to the control module and is used to output the induced current to the control module; the control module is used to obtain the effective current value of the induced current and use it as the representation value of the effective current in the main loop current; and when the effective value of the induced current is greater than or equal to the set current and the duration reaches the set time, the first release 4 is controlled to drive the main contact 31 to disconnect. The above-mentioned method of obtaining the representation value of the effective current in the main loop current through the current transformer is applicable to applications where the current in the main loop circuit 3 is relatively large.

[0030] Optionally, if the first release 4 can be an electronic release or an electromagnetic release, such as an electromagnetic release, the control unit 5 can directly send a control signal to control the first release 4 to operate and disconnect the main contact 31; if the first release 4 is a mechanical release, such as a free tripping mechanism, the control unit 5 may include an actuator 51, and the actuator 51 is connected to the first release 4. The control module is specifically used to control the first release 4 to drive the main contact 31 to disconnect through the actuator 51, that is, the control module sends a control signal to activate the actuator 51.

[0031] Reference Figures 2-3 The control module includes a sampling submodule, a processing submodule and a driving submodule, wherein the sampling submodule is used to sample the induced current of the current transformer to obtain multiple discrete current values; the processing submodule is used to calculate the effective current value of the corresponding induced current according to the multiple discrete current values, and obtain the duration of the effective current value of the induced current being greater than or equal to the set current, and issue a control instruction when the duration reaches the set time; the driving submodule controls the actuator 51 to push the first release 4 according to the control instruction to disconnect the main contact 31. In addition, the control module can be specifically a control circuit board.

[0032] Optionally, the actuator 51 may be an electromagnetic release or an electronic release. In the embodiment of the present invention, the actuator 51 adopts an electromagnetic release, which can provide reliable short-circuit protection for the main circuit 3, and has low cost, long life, and is less affected by the environment.

[0033] Reference Figure 1, the main contact 31 is connected with an elastic member 6, the above-mentioned first releaser 4 is a connecting rod assembly, including a first connecting rod 41, a second connecting rod 42 and a driving rod 43, the first connecting rod 41 is fixedly connected to the main contact 31, the second connecting rod 42 is buckled with the end of the first connecting rod 41, and the driving rod 43 is fixedly connected to the second connecting rod 42. The above-mentioned electromagnetic releaser includes a first magnet 511 and a second magnet 512, and a push rod 513 is connected to the first magnet 511. When (the control unit 5 controls) the first magnet 511 to move toward the second magnet 512, the push rod 513 on the first magnet 511 pushes the driving rod 43 (upward) to move, so that the first connecting rod 41 is disengaged from the second connecting rod 42, and the elastic member 6 drives the main contact 31 and the first connecting rod 41 back to the disconnected position, thereby realizing the function of disconnecting the main contact 31 when a circuit fault (such as a short circuit) occurs.

[0034] Furthermore, in order to prevent the circuit from being overloaded, the circuit breaker of the embodiment of the present invention further includes a thermal release 7, which includes an electric heating element 71 (such as a metal wire) and a bimetallic strip 72. The electric heating element 71 is connected in series in the main loop circuit 3, such as Figure 1 As shown, when the circuit is overloaded, the electric heating element 71 will heat up. When the temperature of the electric heating element 71 is high, the bimetallic strip 72 is deformed and pushes the driving rod 43 to move, so that the first connecting rod 41 and the second connecting rod 42 are disengaged, and the elastic member 6 drives the main contact 31 back to the disconnected position, so that the circuit breaker has the function of overload protection. In addition, the circuit breaker may also include an undervoltage release, a shunt release, etc.

[0035] Reference Figure 4 The embodiment of the present invention further includes a circuit breaker control method, which is used for the circuit breaker described in the above embodiment. The control method includes the following steps:

[0036] When the main contacts are closed, the characterization value Is of the effective current in the main circuit and the duration Ts during which the characterization value of the effective current is greater than or equal to the set current are obtained;

[0037] If the duration Ts reaches the set time, the first release is controlled to drive the main contact to open; wherein, before the duration Ts reaches the set time, the main contact remains in the closed state.

[0038] The control method for a circuit breaker provided in an embodiment of the present invention is applied to a circuit breaker and can achieve the same technical effect as the circuit breaker in the above embodiment.

[0039] On the basis of the above control method, the step of obtaining the characterization value Is of the effective current in the main loop circuit specifically includes: obtaining the effective current value of the induced current output by the current transformer as the characterization value Is of the effective current in the main loop circuit; and when the effective current value of the induced current is greater than or greater than or equal to the set current duration Ts for a set time, controlling the first release to drive the main contact to disconnect.

[0040] Furthermore, the above-mentioned step of obtaining the effective current value of the induced current of the main loop circuit as the characterization value of the effective current in the main loop circuit specifically includes:

[0041] Sampling the induced current of the main loop circuit to obtain a plurality of discrete current values;

[0042] The corresponding effective current value of the induced current is calculated according to the multiple discrete current values.

[0043] In addition, when the control unit includes an actuator, if the duration reaches a set time, the step of controlling the first release to drive the main contact to disconnect specifically includes:

[0044] When the duration Ts reaches the set time, a control instruction is issued;

[0045] According to the control instruction, the actuator is controlled to push the first release to disconnect the main contact.

[0046] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A circuit breaker, comprising a main circuit connected between an incoming terminal and an outgoing terminal, the main circuit comprising a main contact, the main contact being connected to a first release, the first release being used to drive the main contact to disconnect, the circuit breaker being suitable for controlling an LED lamp, characterized in that: It also includes a control unit, which is connected to the first release, and is used to obtain, when the main contact is closed, a characterization value of the effective current in the main circuit and a duration during which the characterization value of the effective current is greater than or equal to a set current, and if the duration reaches the set time, control the first release to drive the main contact to open; wherein, before the duration reaches the set time, the main contact remains in a closed state; The main contact is connected to an elastic member, and the first release comprises a first connecting rod fixedly connected to the main contact, a second connecting rod buckled with an end of the first connecting rod, and a driving rod fixedly connected to the second connecting rod; The control unit also includes an actuator, which is an electromagnetic release. The electromagnetic release includes a first magnet and a second magnet. A push rod is connected to the first magnet. When the first magnet moves toward the second magnet, the push rod on the first magnet pushes the drive rod to move so that the first connecting rod is disengaged from the second connecting rod, and the elastic member drives the main contact and the first connecting rod back to the disconnected position.

2. The circuit breaker according to claim 1, characterized in that: The control unit includes a current transformer and a control module, wherein the input end of the current transformer is connected to the main loop circuit, and the output end of the current transformer is connected to the control module and is used to output the induced current to the control module; the control module is used to obtain the effective current value of the induced current as a characterization value of the effective current in the main loop circuit; and when the effective current value of the induced current is greater than or equal to the duration of the set current for a set time, the first release is controlled to drive the main contact to disconnect.

3. The circuit breaker according to claim 1, characterized in that: The control unit includes a current transformer and a control module. The actuator is connected to the first release. The control module is specifically used to control the first release through the actuator to drive the main contact to disconnect.

4. The circuit breaker according to claim 3, characterized in that: The control module comprises: A sampling submodule, the sampling submodule is used to sample the induced current of the current transformer to obtain a plurality of discrete current values; a processing submodule, the processing submodule being used to calculate the corresponding effective current value of the induced current according to the multiple discrete current values, and obtain the duration of the effective current value of the induced current being greater than or equal to the set current, and issuing a control instruction when the duration reaches the set time; A driving submodule, wherein the driving submodule controls the actuator to push the first release according to the control instruction, so as to disconnect the main contact.

5. A circuit breaker control method, characterized in that: For the circuit breaker according to any one of claims 1 to 4, the control method comprises the following steps: When the main contacts are closed, obtaining a characterization value of an effective current in the main loop circuit and a duration during which the characterization value of the effective current is greater than or equal to a set current; If the duration reaches a set time, the first release is controlled to drive the main contact to open; wherein, before the duration reaches the set time, the main contact remains in a closed state.

6. The control method according to claim 5, characterized in that: The step of obtaining the characterization value of the effective current in the main loop circuit specifically includes: The effective current value of the induced current of the main loop circuit is obtained as a characterization value of the effective current in the main loop circuit.

7. The control method according to claim 6, characterized in that: The step of obtaining the effective current value of the induced current of the main loop circuit as a characterization value of the effective current in the main loop circuit specifically includes: Sampling the induced current of the main loop circuit to obtain a plurality of discrete current values; The corresponding effective current value of the induced current is calculated according to the multiple discrete current values.

8. The control method according to claim 5, characterized in that: When the control unit includes an actuator, the step of controlling the first release to drive the main contact to disconnect if the duration reaches a set time specifically includes: When the duration reaches a set time, issuing a control instruction; According to the control instruction, the actuator is controlled to push the first release to disconnect the main contact.

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