KR101757725B1

KR101757725B1 - Fault current sensing apparatus using hall sensor and arc fire sensing system for smart phone adopting it

Info

Publication number: KR101757725B1
Application number: KR1020160028920A
Authority: KR
Inventors: 최승욱; 최선욱
Original assignee: 주식회사 나래아이오티연구소
Priority date: 2016-03-10
Filing date: 2016-03-10
Publication date: 2017-07-13
Also published as: JP2017161496A; JP6246298B2

Abstract

The present invention provides an apparatus for detecting an abnormal fault current at a high speed using a Hall element in a wiring system to which an AC power source is supplied.
A fault current sensing apparatus using a Hall element according to the present invention includes: a pair of parallel ferrite cores through which individual wires pass; A silicon steel core arranged to surround said pair of ferrite cores; And a saturation flux converter disposed between the pair of ferrite cores and the silicon steel core to convert the saturation flux into an accident voltage.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a fault current sensing device using a hall element, and an arc fire sensing system for a smart phone using the same.

The present invention relates to an apparatus for detecting an accident current using a Hall element, and more particularly to an apparatus for detecting an abnormal fault current at a high speed using a Hall element in a wiring system to which an AC power source is supplied, .

Recently, current sensors are used in many industrial fields, and demands for high sensitivity and the like are increasing. Various current sensors have been developed to realize high sensitivity, and an example thereof is disclosed in Patent Document 1.

The leak sensor of Patent Document 1 is composed of a sensor which is made of a ring-shaped magnetic body (magnetic core) and which detects a change of the magnetic field, a magnetic impedance element whose impedance is changed by a change of the magnetic field generated in the sensor, And a detector for detecting an impedance change of the impedance element. Fig. 1 is a diagram showing the structure of a conventional magnetic core disclosed in Patent Document 1. Fig. 1 (a) is a sectional view of a magnetic core 100a in which a cut portion 101 is provided and a magnetic impedance element 103 are mounted. 1B is a schematic view showing a state in which a notch 102 is provided in the magnetic core 100b and a magnetic impedance element 103 is placed on the notch 102. Fig.

The above configuration realizes a current sensor that more efficiently transfers a change in the magnetic field of the magnetic cores 100a and 100b to the magnetic impedance element 103. [

: Japanese Patent Application Laid-Open No. 10-232259 (published on September 2, 1998) (Patent Document 2): Korean Patent Registration No. 10-1259326 (published on May 5, 2013)

However, the magnetic cores 100a and 100b of Patent Document 1 have the following problems.

The magnetic core 100a of Fig. 1 (a) is provided with a cut-away portion 101 for cutting the magnetic core 100a, and the magnetic impedance element 103 is placed on the cut portion 101. [ Therefore, it is necessary to increase the width of the cut portion 101, and the sensitivity of the magnetic core 100a is lowered. As a result, the leak sensor including the magnetic core 100a in Fig. 1 (a) has a problem that the detection sensitivity is lowered.

The magnetic core 100b shown in Fig. 1 (b) has a notch 102 in which a part of the magnetic core 100b is cut along the outer edge of the magnetic core 100b, (103). However, in this structure, since the magnetic flux is hardly leaked from the magnetic core 100b, the magnetic velocity detected by the magnetic impedance element 103 becomes small. As a result, the magnetic core 100b of Fig. 1 (b) has a problem that the detection sensitivity is lowered.

As described above, the leakage current sensor including the conventional magnetic cores 100a and 100b has a low sensitivity and a problem that the value to be detected is buried in noise.

On the other hand, the ferrite core used in the current sensor of the prior art is fragile due to the characteristics of the material, and thus has a problem that it is difficult to process the ferrite core so as to have a cut-out portion.

Further, according to the prior art, there is a problem that it is not easy to convert only the saturated magnetic flux into the ripple voltage and detect it as an accident current.

Accordingly, the present invention provides an apparatus for detecting an abnormal fault current at high speed using a Hall element in a wiring system to which an AC power source is supplied.

In addition, the present invention provides an apparatus for detecting a fault current at a high speed including an instantaneous short circuit such as insulation failure, deformation of an insulator due to overheating, and short circuit.

Further, the present invention provides an apparatus for detecting magnetic flux leaking when a fault current is generated using a Hall element by using high-frequency characteristics and magnetic saturation characteristics of a ferrite core.

Further, the present invention provides an apparatus for detecting magnetic flux leaking when a fault current is generated using a Hall element by using a low frequency characteristic and an external magnetic field shielding characteristic of a silicon steel core.

The present invention also provides an apparatus for detecting a Hall element sensitive to a saturated magnetic flux by an overcurrent using a structure in which a ferrite core is surrounded by a silicon steel core.

In addition, the present invention can be applied to a case where an accident current is generated due to an arc, by notifying an administrator possessing a remote smart phone, and by applying an accident current sensing device using a Hall element, Provides an arc fire detection system for smartphones.

A fault current sensing apparatus using a Hall element according to the present invention includes: a pair of parallel ferrite cores through which individual wires pass; A silicon steel core arranged to surround said pair of ferrite cores; And a saturation flux converter disposed between the pair of ferrite cores and the silicon steel core to convert the saturation flux into a ripple voltage.

A square wave generator for generating a square wave corresponding to a ripple voltage output from the saturation flux converter; A ground potential detector for detecting ground potential of the AC voltage and outputting a ground potential detection signal; A delay signal generator for outputting a delay signal delayed by a predetermined time from a falling edge of the ground potential detection signal output from the ground potential detector; And a fault current detector that outputs a fault current by logically combining a square wave output from the square wave generator and a delay signal output from the delay signal generator.

The square wave generator may further include: a smoothing unit for smoothing the ripple voltage to generate a ripple average voltage; A pulsation average upper voltage generator for generating a pulsation average upper voltage which is a predetermined level higher than the pulsation average voltage; And a first comparator for comparing the ripple average upper voltage applied to the first inverting terminal and the ripple voltage applied to the first non-inverting terminal to output a rectangular wave.

The non-inverting voltage detecting unit may include a non-inverting voltage-dividing resistor unit configured to receive a predetermined positive voltage and a ground voltage to form a non-inverting voltage of a predetermined level; An inverting voltage-dividing resistor unit configured to receive a predetermined positive voltage and a ground voltage to form a predetermined inverting voltage; A fourth unidirectional element disposed between the second non-inverting terminal and the terminal for drawing the AC voltage so as to be conductive in the lower half period of the AC voltage; A fifth unidirectional element disposed between the second inverting terminal and the terminal for drawing the alternating voltage so as to be conductive in the opposite half period of the alternating voltage; And a second comparator having the second non-inverting terminal for receiving the non-inverting voltage and the second inverting terminal for receiving the inverting voltage, wherein the non-inverting voltage is higher than the inverting voltage by a predetermined level .

The delay signal generator includes: an integrator for integrating the zero-potential detection signal and outputting an integration signal; A reference voltage supplier for receiving the predetermined positive voltage and the ground voltage and providing a reference voltage; And a third comparator that compares the integrated signal applied to the third non-inverting terminal with the reference voltage applied to the third inverting terminal to generate a delay signal.

Also, the reference voltage supplier may be a variable resistor or a voltage dividing resistor.

Further, the pair of ferrite cores may be any of a hollow cylindrical type having no cut-out portion, a ring-type having no cut-out portion, and a hollow prismatic type having no cut-out portion.

According to another aspect of the present invention, there is provided an arc fire detection system including an electric distribution board including a fault current sensing device and including a breaker; And an arc fire detection control unit that includes the gateway and sends the fault current detection signal to the smartphone and operates the breaker of the switchboard under the control of the fault current detection signal.

According to another aspect of the present invention, there is provided an arc fire detection system including an electric distribution board including a fault current sensing device and including a breaker; And an arc fire detection control unit that includes the gateway and transmits the fault current detection signal to the smartphone and operates the breaker of the switchboard under the control of the blocking operation control signal received from the smart phone.

According to the present invention, it is possible to detect an abnormal fault current in an interconnection system to which AC power is supplied at a high speed by using a hall sensor, and to measure an accident current including an instantaneous short circuit such as insulation failure, And it is possible to detect the magnetic flux leaked by the Hall sensor when the fault current is generated by using the high frequency characteristic and the magnetic saturation characteristic of the ferrite core.

In addition, according to the present invention, it is possible to detect a magnetic flux leaked when a fault current is generated by using a low frequency property and an external magnetic field shielding property of a silicon steel core, and to use a structure in which a ferrite core is surrounded by a silicon steel core, It can respond only to magnetic flux.

In addition, in the case of the conventional overload circuit breaker for home, it is prescribed that the power is cut off when a current of several times the rated capacity flows for a predetermined time period to prevent frequent malfunctions. Even if a fire occurs due to an arc phenomenon, It does not work. This is because the overload circuit breaker operates only when the current continuously flows. However, since the arc does not continuously occur, it is impossible to prevent the fire caused by the arc, but according to the present invention, this problem can be solved.

1 is a schematic diagram of a leakage current sensor with a magnetic core according to the prior art,
Figure 2 is a photograph of a Hall element according to an embodiment of the present invention,
3 is a front view of a Hall element according to an embodiment of the present invention,
FIG. 4 is a conceptual diagram of a saturated magnetic flux sensing of a Hall element according to an embodiment of the present invention,
5 is a circuit diagram of a fault current detection using a Hall element according to an embodiment of the present invention.
6 is a diagram of a Hall element signal waveform according to an embodiment of the present invention, and Fig.
FIG. 7 is an overall configuration diagram of an arc fire detection system for a smartphone to which an accident current sensing device using a Hall device according to an embodiment of the present invention is applied.

Further objects, features and advantages of the present invention will become more apparent from the following detailed description and the accompanying drawings.

Before describing the present invention in detail, it is to be understood that the present invention is capable of various modifications and various embodiments, and the examples described below and illustrated in the drawings are intended to limit the invention to specific embodiments It is to be understood that the invention includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprises" or "having" and the like refer to the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

In the following description of the present invention with reference to the accompanying drawings, the same components are denoted by the same reference numerals regardless of the reference numerals, and redundant explanations thereof will be omitted. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

FIG. 2 is a photograph of a Hall element according to an embodiment of the present invention, and FIG. 3 is a front view of a Hall element according to an embodiment of the present invention.

The Hall element according to one embodiment of the present invention includes a pair of parallel ferrite cores 220 through which individual wires pass, a silicon steel core 210 arranged to surround the pair of ferrite cores 220, And a Hall sensor 230 disposed between the pair of ferrite cores 220 and the silicon steel core 210. Here, the pair of ferrite cores 220 may be a hollow cylindrical type having no cutout portion, a ring type having no cutout portion, or a hollow prismatic type having no cutout portion.

The ferrite core 220 is a hollow cylindrical core that passes through the AC power wiring to serve as an inductor for harmonic noises. The ferrite core 220 passes the wiring connected to the load side and generates harmonic noises or magnetic flux of the core due to a normal current And the magnetic flux flowing from the outside rotate in the core to prevent the Hall sensor 230 from sensing.

The silicon steel core 210 focuses the magnetic flux generated by the low frequency current flowing to the load through the AC power wiring and flows the magnetic field from the outside through the core to prevent the Hall sensor 230 from sensing.

That is, the ferrite core 220 and the silicon steel core 210 minimize the influence of the Hall sensor 230 on the magnetic flux due to the external magnetic field or harmonics, rather than the effect of collecting the magnetic flux, (230) can be caused to respond.

4 is a conceptual diagram for sensing the saturation flux of a Hall sensor according to an embodiment of the present invention.

4A shows a flow of magnetic flux when a normal magnitude current flows through the AC power wiring and the magnetic flux is not saturated, and the Hall sensor 230 can not sense the magnetic flux.

FIG. 4B shows the flow of magnetic flux when the magnetic flux flowing through the core is saturated due to an overcurrent flowing through the AC power wiring. The Hall sensor 230 can sense the magnetic flux.

4C shows the flow of magnetic flux in the case where the magnetic flux by the external magnetic field passes through the core and escapes to the outside, so that the Hall sensor 230 can not sense the magnetic flux.

FIG. 5 is a circuit diagram of a Hall sensor signal processing apparatus according to an embodiment of the present invention, and FIG. 6 is a Hall sensor signal waveform diagram according to an embodiment of the present invention.

The hall sensor signal processing circuit according to an embodiment of the present invention includes a saturated magnetic flux converting unit 510, a square wave generating unit 520, a ground potential detecting unit 530, a delay signal generating unit 540, 550).

The saturation flux converter 510 converts the saturation flux of the core into an accident voltage and outputs it. The saturation flux converter 510 includes a Hall sensor 511 (HES), two diodes 512 and 513, and a resistor R1. The Hall sensor 511 includes two input wirings for receiving a positive voltage (V +) and a ground voltage (G), two output lines for converting the output voltage into a voltage when the magnetic flux is saturated in the core due to the overcurrent Respectively. The two diodes 512 and 513 connected to the output side of the Hall sensor 511 respectively receive the half cycle (0 to 180 degrees) and the lower half cycle (180 to 360 degrees) of the AC voltage, (See Fig. 6, node N6).

The square wave generating unit 520 generates and outputs a rectangular wave corresponding to the ripple voltage output from the saturation magnetic flux converting unit 510. The square wave generating unit 520 includes smoothing units 521 and 522, pulsation upper voltage generating units 523 and 524, and a first comparator 525. Smoothing portions 521 and 522 smoothen the ripple voltage to form a ripple-average voltage. The diode D3 of the pulsating upper voltage generating units 523 and 524 forms a pulsating average upper voltage which is higher than the pulsation average voltage applied to the capacitor C1 by a predetermined level (for example, 0.7 volt) To the inverting terminal (-). The first comparator 525 outputs a square wave corresponding to the pulsating voltage when a pulsating voltage that rises to the non-inverting terminal (+) is applied in comparison with the pulsating average upper voltage applied to the inverting terminal (-) N7).

The spontaneous voltage detector 530 detects the spontaneous voltage of the AC voltage and outputs a spontaneous voltage detection signal. The non-inverting voltage-dividing resistor unit 533 arranged to apply the non-inverting voltage of a predetermined level to the non-inverting terminal of the second comparator 537 by receiving the positive voltage (V +) and the ground voltage (G) 534), inverting voltage-dividing resistors (535, 536) arranged to apply a positive voltage (V +) and a ground voltage (G) and apply a predetermined inverting voltage to the inverting terminal of the second comparator (537) A fourth unidirectional element 531 disposed between the non-inverting terminal of the second comparator 537 and the alternating voltage terminal so as to conduct in the lower half period of the second comparator 537, the inverting terminal of the second comparator 537 to be conductive in the opposite half period of the alternating voltage A fifth unidirectional element 532 disposed between the AC voltage terminals, and a second comparator 537 for comparing the non-inverted voltage with the inverted voltage and outputting the over-current detection signal. Here, the resistance ratio between the non-inverting voltage-division resistor units 533 and 534 and the inverting voltage-division resistor units 535 and 536 needs to be adjusted so that the non-inverting voltage of the predetermined level is slightly higher than the inverting voltage of the predetermined level. Accordingly, the second comparator 537 outputs the "L" level signal in the vicinity of the positive potential of the alternating voltage, that is, near 0 degrees and 180 degrees, and outputs the "H" level signal in the remaining phases , N2).

The delay signal generator 540 outputs a delay signal that delays the rising edge of the ground potential detection signal output from the ground potential detector 530 by a predetermined time. The delay signal generator 540 includes integrators 541, 542, and 543 configured to integrate the zero-potential detection signal and apply an integration signal (see FIG. 6, node N3) to the non-inverting terminal of the third comparator 545, A reference voltage supplier 544 configured to receive a voltage V + and a ground voltage G to apply a reference voltage of a predetermined level to an inverting terminal of the third comparator 545, And a third comparator 545 for generating a signal (see FIG. 6, node N4). The delay signal generator 540 is provided to eliminate the possibility of recognizing the transient current flowing in the capacitor near the zero potential, that is, about 0 or 180 degrees, as the fault current. According to one embodiment of the present invention, the reference voltage supplier 544 may be implemented as a variable resistor. That is, by adjusting the variable resistor, the reference voltage level can be adjusted and the rising edge timing of the electromotive force detection signal can be adjusted. In other words, the phase of the zero potential detection signal can be adjusted. According to another embodiment of the present invention, it is needless to say that the output voltage of the over-current detection signal can be fixed by implementing the reference voltage supplier 544 as a voltage divider resistor in series.

The fault current detection unit 550 detects the fault current by logically combining the square wave output from the square wave generating unit 520 and the delay signal output from the delay signal generating unit 540 and outputs the fault current detection signal.

When no overcurrent flows in the AC wiring (refer to FIG. 6, node N5, section I), the magnetic flux is not saturated in the core and there is no output from the Hall sensor (refer to FIG. 6, node N6, section I).

When the overcurrent flows in the AC wiring (refer to FIG. 6, node N5, and section II), the magnetic flux flowing through the core is saturated and the ripple voltage is output from the Hall sensor (see FIG. 6, node N6, section II). At this time, the square wave generating unit 520 outputs a square wave corresponding to the ripple voltage (see FIG. 6, node N7, and interval II), and the fault current detecting unit 550 detects the fault current by logically combining the square wave and the delay signal .

FIG. 7 is an overall configuration diagram of an arc fire detection system for a smartphone to which an accident current sensing device using a Hall device according to an embodiment of the present invention is applied.

The arc fire detection system for a smartphone according to an embodiment of the present invention may include an alarm device 200 for detecting an arc of a fire, a fault current detection circuit unit 500 (FIG. 5), an electric distribution board 600, an arc fire detection control unit 700, And a smartphone 800.

The switchboard 600 may include a circuit breaker.

The arc fire detection control unit 700 includes a gateway and is wirelessly coupled to the fault current detection circuit unit 500 and the switchboard 600 in a wired or wireless manner and can be wirelessly coupled to the smart phone 800 possessed by the manager.

When an accident current detection signal is output from the fault current detection circuit unit 500, the arc fire detection control unit 700 can send a fault current detection signal to the smartphone 800 and operate the breaker of the switchboard 600. In addition, according to another embodiment of the present invention, when an accident current detection signal is output from the fault current detection circuit unit 500, the arc fire detection control unit 700 transmits an accident current detection signal to the smart phone 800, It is possible to operate the breaker of the switchboard 600 by controlling the cutoff operation control signal received from the phone 800. [

The embodiments and the accompanying drawings described in the present specification are merely illustrative of some of the technical ideas included in the present invention. Accordingly, the embodiments disclosed herein are for the purpose of describing rather than limiting the technical spirit of the present invention, and it is apparent that the scope of the technical idea of the present invention is not limited by these embodiments. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

210: Silicon steel core
220: ferrite core
230: Hall sensor
510: Saturated flux converter
520: Square wave generator
530:
540: delay signal generator
550: fault current detector

Claims

A pair of parallel ferrite cores through which individual wirings pass;
A silicon steel core arranged to surround said pair of ferrite cores; And
And a saturation magnetic flux converting unit disposed between the pair of ferrite cores and the silicon steel core to convert the saturated magnetic flux into a ripple voltage,
Wherein the fault current detection device comprises a Hall element.

The method according to claim 1,
A square wave generator for generating a square wave corresponding to a ripple voltage output from the saturation flux converter;
A ground potential detector for detecting ground potential of the AC voltage and outputting a ground potential detection signal;
A delay signal generator for outputting a delay signal delayed by a predetermined time from a falling edge of the ground potential detection signal output from the ground potential detector; And
And a fault current detector for outputting an fault current detection signal by logically combining a square wave output from the square wave generator and a delay signal output from the delay signal generator,
Further comprising a Hall element.

The apparatus of claim 2, wherein the square-
A smoothing unit for smoothing the ripple voltage to generate a ripple average voltage;
A pulsation average upper voltage generator for generating a pulsation average upper voltage which is a predetermined level higher than the pulsation average voltage; And
A first comparator for comparing the ripple average upper voltage applied to the first inverting terminal with the ripple voltage applied to the first non-inverting terminal to output a rectangular wave,
Wherein the fault current detection device comprises a Hall element.

[3] The apparatus of claim 2,
A non-inverting voltage-dividing resistor portion configured to receive a predetermined positive voltage and a ground voltage to form a non-inverting voltage of a predetermined level;
An inverting voltage-dividing resistor unit configured to receive a predetermined positive voltage and a ground voltage to form a predetermined inverting voltage;
A fourth unidirectional element disposed between the second non-inverting terminal and the terminal for drawing the AC voltage so as to be conductive in the lower half period of the AC voltage;
A fifth unidirectional element disposed between the second inverting terminal and the terminal for drawing the alternating voltage so as to be conductive in the opposite half period of the alternating voltage; And
And a second comparator having the second non-inverting terminal for receiving the non-inverting voltage and the second inverting terminal for receiving the inverting voltage,
Wherein the non-inverting voltage is higher than the inverting voltage by a predetermined level.

The apparatus of claim 4, wherein the delay signal generator comprises:
An integrator for integrating the zero potential detection signal and outputting an integration signal;
A reference voltage supplier for receiving the predetermined positive voltage and the ground voltage and providing a reference voltage; And
A third comparator for comparing the integrated signal applied to the third non-inverting terminal with the reference voltage applied to the third inverting terminal to generate a delay signal,
Wherein the fault current detection device comprises a Hall element.

6. The method of claim 5,
Wherein the reference voltage supplier is a variable resistor or a voltage divider resistor.

3. The method of claim 2,
Wherein the pair of ferrite cores is a hollow cylindrical type having no cutout portion, a ring type having no cutout portion, and a hollow prismatic type having no cutout portion.

A fault current detection device according to any one of claims 2 to 7,
An electrical distribution board including a breaker; And
And an arc fire detection control unit for controlling the breaker of the switchboard in response to the fault current detection signal,
And an arc fire detection system.

A fault current detection device according to any one of claims 2 to 7,
An electrical distribution board including a breaker; And
And an arc fire detection control unit which includes a gateway and transmits the fault current detection signal to the smartphone and is controlled by a blocking operation control signal received from the smart phone to operate the breaker of the switchboard,
And an arc fire detection system.