WO2008154787A1

WO2008154787A1 - Defective arc protection breaker

Info

Publication number: WO2008154787A1
Application number: PCT/CN2007/070162
Authority: WO
Inventors: Gang Xing; Naiwu Yuan
Original assignee: Gang Xing; Naiwu Yuan
Priority date: 2007-06-18
Filing date: 2007-06-22
Publication date: 2008-12-24
Also published as: CN201051651Y

Abstract

A defective arc protection breaker comprises a signal sampling module(3) provided with a sampling unit and mounted inside an electric equipment, a microcomputer control unit(2), a contact switch(1) and a current detecting module(4) mounted on incoming line terminals of a power grid. The signal sampling module(3) sends signal of the sampling circuit of a sampling unit(31) to the microcomputer control unit(2) to process. The microcomputer control unit(2) controls on-off of the contact switch(1). The current signal sampling transformer of the sampling unit(31) is a hollow inductor.

Description

Fault arc protection circuit breaker

The present invention relates to an electrical failsafe device, and more particularly to a circuit breaker for protecting a fault arc. Background technique

The existing power failure protection devices are classified into a Ground-fault Circuit Interrupter, a Leakage Current Detector Interrupter, and an Arc-Fault Circuit Interrupter.

The ground fault circuit breaker (GFCI) is mainly used to protect the ground fault. When there is current flowing through the live or neutral line in the appliance, the GFCI will act and cut off the power. The protector is mainly used to prevent people from having an electric shock when using the electric appliance, and to disconnect the power supply in time to prevent the human body from getting an electric shock.

Leakage current detection circuit breaker (LCDI) is mainly used to prevent fire caused by arcing on the connected power line. When an arc occurs on the power line, the circuit breaker will be disconnected due to special protection devices on the wire to prevent arc from causing fire. .

The fault arc break protector (AFCI) is mainly used for the detection of arc faults, not only for the detection of false arcs on the wires, but also when the arc of the electrical parts other than the wires is arced, the AFCI judges the identification errors by detecting the current signals in the circuits. Arc and normal arc, when a fault arc that may cause a fire occurs in the circuit, AFCI cuts off the circuit in time to prevent fire.

Figure 1 shows a functional module of one embodiment of a prior art fault arc protection circuit breaker. Referring to Fig. 1, the circuit breaker is mainly composed of a contact switch 1, a microcomputer control unit 2 and a signal sampling module 3. The contact switch 1 is disposed at one end of the power supply line 5 for controlling the turning on and off of the power line 5, and the signal sampling module 3 is disposed at one end of the power device of the power line 5. When an arc occurs in the circuit, the signal sampling module 3 collects the relevant signal and sends it to the microcomputer control unit 2 for processing. When the arc is a fault arc, the microcomputer control unit 2 sends a trigger signal to the contact switch 1 to turn it off. The contact switch 1 can be an electromagnetically triggered contact switch.

The sampling unit 31, the band pass filtering unit 32, the amplifying unit 33, and the integrating unit 34 are sequentially connected in series inside the signal sampling module 3. The sampling unit 31 is connected to one end of the power device of the power line 5, and the output end of the integrating unit 34 is connected to the microcomputer control unit 2. The sampling unit 31 collects the high-frequency current signal in the power line 5, and the collected high-frequency current signal passes through the band-pass filtering unit 32 to become a signal of a frequency band required by the system. The band signal is amplified by the amplifying unit 33 to become a signal of an ideal amplitude that can be utilized by the system, and the integrating unit 34 integrates the signal into the microcomputer control unit 2. Through the above processing, the microcomputer control unit 2 can detect the running condition of the power line in real time. When an abnormal state occurs, the microcomputer control unit 2 judges whether the abnormal state that occurs is a normal arc or a fault arc according to the characteristics of the signal. If it is a fault arc, the microcomputer control unit 2 issues a trigger signal to open the contact switch through the electromagnetic trigger, thereby avoiding a hazard such as a fire caused by the fault arc.

Fig. 2 shows a functional module of another embodiment of a prior art fault arc protection circuit breaker. As shown in FIG. 2, this embodiment is basically the same as the embodiment of FIG. 1. The only difference is that the amplifying unit 33' and the band pass filtering unit 32' process the signals in the reverse order, that is, the first use of the amplifying unit 33' The current signal is amplified, and the amplified signal is converted into a frequency band signal required by the system by the band pass filtering unit 32'. Such a module structure can also achieve the above functions.

When AFCI detects a current signal, it needs to collect the current signal of the unique frequency band when the arc occurs. The prior art uses a magnetically permeable material as the current sensor of the magnetic core. This current acquisition method causes nonlinearity of the signal due to the saturation characteristics of the magnetic material, which is not conducive to the correct judgment of the signal. In addition, the current detecting module is not used in the prior art, and the microcomputer control system has relatively few judgments, and the switching operation mode is single. Summary of the invention

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and to provide a fault arc protection circuit breaker capable of linearly collecting a current signal when an arc occurs in any part of the circuit, which is advantageous for making a correct judgment on the signal. Moreover, the current detecting module is adopted, and the microcomputer control system takes different protection time actions according to different currents in the circuit. Improve efficiency and realize the intelligent recognition action function of the circuit breaker.

The technical solution of the present invention is as follows: The present invention provides a fault arc protection circuit breaker, comprising a signal sampling module, a microcomputer control unit, and a contact switch installed at the incoming end of the power grid, which are installed on the end of the power device and provided with a sampling unit. The signal sampling module is sent to the microcomputer control unit for processing by using the signal in the sampling unit acquisition circuit, wherein the circuit breaker further includes a current detecting module connected to the end of the power device, and the detecting flows through the The current signal of the sampling unit sends the processed signal to the microcomputer control unit, and the microcomputer control unit controls opening and closing of the contact switch according to the signal sent by the signal sampling module and the current detecting module.

The fault arc protection circuit breaker, wherein the current detection module further comprises: an AC signal filtering unit, filtering the current signal on the sampling unit into a minute AC signal; An amplifying unit is connected to the alternating current signal filtering unit to amplify the tiny alternating current signal into a current signal recognizable by the microcomputer control unit.

In the above-mentioned fault arc protection circuit breaker, the current signal sampling transformer of the sampling unit adopts a hollow inductor.

The fault arc protection circuit breaker, wherein the signal sampling module further comprises a band pass filtering unit, an amplifying unit and an integrating unit serially connected to the sampling unit, wherein the band pass filtering unit converts the collected current signal The frequency band signal required by the system, the amplifying unit amplifies the frequency band signal, and the integrating unit integrates the amplified frequency band signal into the microcomputer control unit.

In the above-mentioned fault arc protection circuit breaker, the signal sampling module further includes an amplification unit, a band pass filtering unit and an integration unit which are sequentially connected in series with the sampling unit, and the amplification unit amplifies the collected current signal. The band pass filtering unit converts the amplified current signal into a frequency band signal required by the system, and the integrating unit integrates the amplified frequency band signal into the microcomputer control unit.

In the above-mentioned fault arc protection circuit breaker, wherein the contact switch is an electromagnetically controlled contact switch, the above-mentioned fault arc protection circuit breaker, wherein the hollow inductor has a non-magnetic material in its skeleton and no magnetic field in the skeleton. core.

In the above-mentioned fault arc protection circuit breaker, in the hollow inductor, the skeleton thereof is made of a non-magnetic material, and the hollow portion of the skeleton is provided with a magnetic core using a non-magnetic material.

The above-mentioned fault arc protection circuit breaker, wherein the inductance range is 0. 01 micro-henry to 500 micro-henry. The present invention has the following beneficial effects compared with the prior art: The circuit breaker of the present invention is connected in the form of a plug or a socket. Between the electrical equipment and the grid. When a faulty arc that may cause a fire occurs due to aging of the electric equipment, the circuit breaker collects a voltage or current flowing through the electric device through a current signal sampling transformer of a hollow inductor of a non-magnetic material skeleton, and passes the current detection. The module collects the current collected by the current signal sampling transformer and outputs it to the microcomputer control unit. The microcomputer control unit detects the fault arc and triggers the electric shock switch to open the circuit, thereby extinguishing the fault arc in time to prevent fire and other faults. BRIEF abstract 1 is a functional block diagram of one embodiment of a prior art fault arc protection circuit breaker.

2 is a functional block diagram of another embodiment of a prior art fault arc protection circuit breaker.

3 is a functional block diagram of one embodiment of a fault arc protection circuit breaker of the present invention.

4 is a functional block diagram of another embodiment of a fault arc protection circuit breaker of the present invention.

Fig. 5 is a perspective structural view showing a preferred embodiment of the hollow inductor of the sampling unit transformer in the fault arc protection circuit breaker of the present invention.

Figure 6 is a cross-sectional view of the embodiment of Figure 5.

Fig. 7 is a perspective structural view showing another preferred embodiment of the hollow inductor of the sampling unit transformer in the fault arc protection circuit breaker of the present invention.

Figure 8 is a cross-sectional view of the embodiment of Figure 7. BEST MODE FOR CARRYING OUT THE INVENTION

The invention will now be further described with reference to the drawings and embodiments.

Figure 3 illustrates the principles of a preferred embodiment of the present invention. Referring to FIG. 3, this embodiment adds a current detecting module 4 to the existing fault arc protection circuit breaker shown in FIG. That is, the fault arc protection circuit breaker includes: a contact switch 1, a signal sampling module 3, a current detecting module 4, and a microcomputer control unit 2. The internal structure of the signal sampling module 3 and the working principle of the module are the same as those of the prior art, and therefore will not be described again. The current detecting module 4 detects the current signal flowing through the sampling unit 31, processes it, and sends it to the microcomputer control unit 2. The microcomputer control unit 2 detects the running status of the power line in real time according to the signal sent by the signal sampling module 3 and the current detecting module 4. When an abnormal state occurs, the microcomputer control unit 2 according to the characteristics of the signal (for example, the current signal is suddenly greater than the preset) Value, etc.) It is judged whether the abnormal state that occurs is a normal arc or a fault arc. If it is a fault arc, the microcomputer control unit 2 issues a trigger signal to open the contact switch 1 through the electromagnetic trigger, thereby avoiding a fire or the like caused by the fault arc.

The current detecting module 4 internally includes an AC signal filtering unit 41 and an amplifying unit 42 connected thereto. The primary side coil of the sampling unit 31 is connected in series in the power supply line 5. When a current flows through the power supply line 5, the current signal on the primary side coil of the sampling unit 31 is filtered by the alternating current signal filtering unit 41 into a minute alternating current signal. The minute AC signal is amplified by the amplifying unit 42 into a current signal recognizable by the microcomputer control unit 2, and then input to the microcomputer control unit 2. Based on this current magnitude and the signal of the integrating unit 34, the microcomputer control unit 2 triggers the contact switch to take different protection time actions. The larger the current, the shorter the protection time. The integration unit 34 is a high frequency arc signal collection back. The road, only when the microcomputer control unit 2 receives the arc signal sent from the integrating unit 34, the excessive current in the power line 5 will speed up the protection time. If the integration unit 34 does not generate an arc signal, no protection will occur even if the current is large.

Figure 4 illustrates the principles of another preferred embodiment of the present invention. Referring to FIG. 4, the difference between the embodiment of FIG. 4 and the embodiment of FIG. 3 is as follows: In the signal sampling module 3, the embodiment of FIG. 3 first performs band-pass filtering, and then amplifies and integrates the signal collected by the sampling unit; For example, the signal collected by the sampling unit is first amplified by the amplifying unit 33', and then filtered by the band pass filtering unit 32' to perform integration. The connection mode and working principle of the remaining modules or units are the same as those in the embodiment of FIG. 3, and therefore will not be described again.

In the above two embodiments, the current signal sampling transformer of the sampling unit 31 may be a conventional inductor or a hollow inductor. The primary side of the sampling transformer 5-10 copper wire is wound around the sampling inductance of the secondary side, preferably a hollow inductor.

In a typical inductor, a coil is wound around a bobbin, a skeleton is hollow, and a magnetic core is mounted therein, wherein the magnetic core is made of a magnetic material. Fig. 5 shows the construction of an embodiment of a current signal sampling inductance in a sampling unit of the present invention. Figure 6 is a cross-sectional view of Figure 5. As shown in Fig. 5 and Fig. 6, the inductor is composed of a coil 51, a skeleton 52, and a magnetic core 53. Compared with the conventional inductor, the skeleton 52 and the magnetic core 53 are made of a non-magnetic material such as a wooden block or a plastic.

Fig. 7 shows the structure of another embodiment of the current signal sampling inductance in the sampling unit of the present invention. Figure 8 is a cross-sectional view of Figure 7. As shown in Fig. 7 and Fig. 8, the inductor is composed of a coil 61 and a bobbin 62. The skeleton 62 is made of a non-magnetic material compared to the conventional inductor, and the core is not mounted therein.

The structure of the above two embodiments can make the inductance value small enough to make the inductance range reach 0.01 microhenry to 500 microhenry. Because only when the inductance value is small enough, it can ensure the acquisition of fine high-frequency signals in the circuit, ensuring linear acquisition of current signals, thus facilitating the processing and detection of abnormal states in the circuit. It should be understood that the invention is based on the use of a current detecting module to detect the magnitude of the processing current as a basis for determining the arc fault, and the embodiment is for illustrative purposes only.

The above embodiments are provided to those skilled in the art to implement or use the present invention. Those skilled in the art can make various modifications or changes to the above embodiments without departing from the inventive concept. Therefore, the scope of the present invention is not limited by the above embodiments, but should be the maximum range of the innovative features mentioned in the claims.

Claims

Rights request

1 A fault arc protection circuit breaker, comprising: a signal sampling module provided with a sampling unit inside a power device end, a microcomputer control unit, a contact switch installed at an incoming end of the power grid, wherein the signal sampling module utilizes the sampling unit The signal in the acquisition circuit is sent to the microcomputer control unit for processing, wherein the circuit breaker further comprises a current detecting module connected to the end of the power device, detecting a current signal flowing through the sampling unit, and processing the processed The signal is sent to the microcomputer control unit, and the microcomputer control unit controls opening and closing of the contact switch according to the signal sent by the signal sampling module and the current detecting module.

The fault arc protection circuit breaker according to claim 1, wherein the current detecting module further comprises:

An AC signal filtering unit filters the current signal on the sampling unit into a small AC signal;

An amplifying unit is connected to the alternating current signal filtering unit to amplify the minute alternating current signal into a current signal recognizable by the microcomputer control unit.

The fault arc protection circuit breaker according to claim 1, wherein the current signal sampling transformer of the sampling unit adopts a hollow inductor.

The fault arc protection circuit breaker according to claim 1 or 3, wherein the signal sampling module further comprises a band pass filtering unit, an amplifying unit and an integrating unit serially connected in series with the sampling unit, the belt The pass filtering unit converts the collected current signal into a frequency band signal required by the system, the amplifying unit amplifies the frequency band signal, and the integrating unit integrates the amplified frequency band signal into the microcomputer control unit. .

The fault arc protection circuit breaker according to claim 1 or 3, wherein the signal sampling module further comprises an amplification unit, a band pass filtering unit and an integration unit serially connected in series with the sampling unit, the amplification The unit amplifies the collected current signal, and the band pass filtering unit converts the amplified current signal into a frequency band signal required by the system, and the integrating unit performs integral processing on the amplified frequency band signal and inputs the microcomputer control unit. The fault arc protection circuit breaker according to claim 1 or 3, wherein the contact switch is an electromagnetically controlled contact switch.

The fault arc protection circuit breaker according to claim 1 or 3, wherein in the hollow inductor, the skeleton is made of a non-magnetic material, and no magnetic core is added to the skeleton.

The fault arc protection circuit breaker according to claim 1 or 3, wherein in the hollow inductor, the skeleton is made of a non-magnetic material, and the hollow portion of the skeleton is provided with a magnetic core using a non-magnetic material.

The fault arc protection circuit breaker according to claim 1 or 3, wherein the inductive range is 0.01 microhenry to 500 microhenry.