KR100469370B1 - A Circuit Breaker for electric leakage - Google Patents

A Circuit Breaker for electric leakage Download PDF

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Publication number
KR100469370B1
KR100469370B1 KR10-2002-0007971A KR20020007971A KR100469370B1 KR 100469370 B1 KR100469370 B1 KR 100469370B1 KR 20020007971 A KR20020007971 A KR 20020007971A KR 100469370 B1 KR100469370 B1 KR 100469370B1
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South Korea
Prior art keywords
current
circuit
earth leakage
microprocessor
breaker
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KR10-2002-0007971A
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Korean (ko)
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KR20030068268A (en
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양영모
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엘지산전 주식회사
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02HEMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/02Details
    • H02H3/05Details with means for increasing reliability, e.g. redundancy arrangements
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02HEMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/26Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents
    • H02H3/32Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors
    • H02H3/34Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors of a three-phase system

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  • Emergency Protection Circuit Devices (AREA)
  • Breakers (AREA)

Abstract

본 발명은 열적으로 안정한 누전 차단기에 관한 것으로, 본 발명의 누전 차단기는 3상의 전력선에 각각 복수개가 설치되어 전자회로부 구동전압을 유도하고 동시에 누전전류를 검출할 수 있는 변류기를 구비하기 때문에 열적으로 안전하다.The present invention relates to a thermally stable earth leakage circuit breaker. The earth leakage circuit breaker of the present invention is thermally safe because a plurality of each of the earth leakage circuit breakers is provided with a current transformer capable of inducing a driving voltage of the electronic circuit unit and detecting a current leakage current at the same time. Do.

Description

누전 차단기{A Circuit Breaker for electric leakage}A circuit breaker for electric leakage

본 발명은 누전 차단기에 관한 것으로, 3상 각각의 교류 전력선으로부터 전자 회로부 구동전압을 공급받고 동시에 누전전류를 검출하기 때문에 열적으로 안정한 누전 차단기에 관한 것이다.BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an earth leakage circuit breaker, and more particularly, to an earth leakage circuit breaker that is supplied with a driving voltage from an AC power line of each of three phases and simultaneously detects a current leakage current.

일반적으로, 전기가 흐르는 모든 회로와 전기 기구 등의 부하측에 누설전류가 발생되면 전기적인 충격에 의해 인체가 손상되고 전기 발화에 의한 화재가 발생될 수 있는바, 이러한 누전을 차단하기 위해 누설 전류를 검출하여 부하측의 전기회로를 개방시키는 누전차단기가 제안되고 있다.In general, when a leakage current is generated on the load side of all circuits and electric appliances through which electricity flows, the human body may be damaged by an electric shock and a fire may occur due to electric ignition. BACKGROUND ART An earth leakage circuit breaker for detecting and opening an electric circuit on a load side has been proposed.

도 1은 종래 기술에 따른 누전 차단기의 회로도이다.1 is a circuit diagram of a circuit breaker according to the prior art.

도 1에 도시된 바와 같이, 종래 기술에 따른 누전 차단기는 R,S,T 3상의 교류전류의 전력선 둘레에서 누설전류를 검출하기 위한 영상변류기(11)와, 상기 영상변류기(11)에서 검출된 전압을 강하시키기 위해 병렬로 연결된 복수개의 저항들(R1,R2,R3)을 스위칭하는 감도선택회로(13)와, 상기 감도선택회로(13)의 입력신호를 받아 누전을 판단하여 제어신호를 출력하기 위한 전용 IC(Integrated Circuit)(15)와, 상기 전용 IC(15)의 제어신호에 따라 구동되는 싸이리스트(17)와, 상기 싸이리스트(17)의 동작에 따라 상기 R,S,T 3상의 주전원을 차단하기 위한 트립코일(19)과, 상기 트립코일(19)에 연결되고 상기 전용 IC(15)에 전원을 공급하기 위한 전원회로(21)를 포함하여 구성된다.As shown in FIG. 1, a ground fault circuit breaker according to the prior art includes an image current transformer 11 for detecting a leakage current around a power line of an AC current of R, S, and T three phases, and the image current transformer 11 detected by the current transformer 11. Sensitivity selection circuit 13 for switching a plurality of resistors (R1, R2, R3) connected in parallel to reduce the voltage and the input signal of the sensitivity selection circuit 13 to determine the short circuit to output a control signal R, S, and T 3 according to the operation of the integrated circuit (IC) 15, a list 17 driven according to a control signal of the dedicated IC 15, and the list 17. And a power supply circuit 21 connected to the trip coil 19 and supplying power to the dedicated IC 15.

이와 같이 구성된 종래 기술에 따른 누전차단기를 설명하면 다음과 같다.Referring to the earth leakage breaker according to the prior art configured as described above is as follows.

먼저, 누전이 발생하면 상기 영상변류기(11)가 3 상의 전류에 있어서 각상의 전류 균형의 붕괴를 감지하여 2 차권선에 기전력을 발생시키고 상기 기전력은 감도선택회로(13)를 통하여 전압이 강하된다.First, when a short circuit occurs, the image current transformer 11 detects the collapse of the current balance of each phase in the three-phase current to generate an electromotive force in the secondary winding, and the electromotive force drops through the sensitivity selection circuit 13. .

또한, 상기 감도선택회로(13)를 통하여 강하된 전압은 상기 전용IC(15)에 인가되고, 상기 전용IC(15)에서 신호를 증폭 및 설정된 감도선택 기준치와 비교하여 기준 초과시 출력을 발생시켜 상기 전용IC(15)의 우측단 싸이리스트(17)를 온"ON" 시키게 되고 상기 싸이리스트(17)가 온"ON" 상태가 되면 트립코일(19)에 전류가 흘러 기구부(도시하지 않음)를 해제시킴으로써 누전 차단기가 동작하게 된다.In addition, the voltage dropped through the sensitivity selection circuit 13 is applied to the dedicated IC 15, and amplifies the signal from the dedicated IC 15 and compares the signal with a set sensitivity selection reference value to generate an output when the reference is exceeded. When the cylist 17 on the right end of the dedicated IC 15 is turned "ON", when the cylist 17 is in the "ON" state, current flows in the trip coil 19 to release the mechanism (not shown). By releasing it, the earth leakage breaker is activated.

하지만, 이와 같은 종래기술에 따른 누전 차단기는 다음과 같은 문제점이 있다.However, the circuit breaker according to the related art has the following problems.

종래 기술의 누전차단기에서 상기 전용IC(15) 및 트립코일(19)을 동작시키기 위해 동작 전압을 선로에서 직접 연결하여 사용하므로 누전 차단기의 전자회로부에서 열 발생 및 열적 스트레스로 인한 전자부품 열화 및 오작동이 발생되어 누전 차단기의 전자회로부가 정상동작을 하지 못할 수 있고, 또 상기 누전 차단기의 오작동으로부터 발생된 누전전류에 의해 화재 및 인명피해가 발생하는 문제점이 있다.In the ground fault circuit breaker of the prior art, since the operating voltage is directly connected to the line to operate the dedicated IC 15 and the trip coil 19, deterioration and malfunction of electronic components due to heat generation and thermal stress in the electronic circuit part of the ground fault breaker There is a problem that the electronic circuit portion of the earth leakage breaker may not be able to operate normally, and there is a problem that fire and human injury occurs by the earth leakage current generated from the malfunction of the earth leakage breaker.

본 발명은 상기와 같은 문제점을 해결하기 위해 안출한 것으로서, 상기 영상변류기를 대신해서 3 상의 전력선에 각각 복수개의 변류기(Current Transformer)를 설치하여 상기 변류기로부터 동작전압을 인가 받아 열적 안정성을 갖는 누전차단기를 제공하는데 그 목적이 있다.The present invention has been made to solve the above problems, a plurality of current transformer (Current Transformer) installed in each of the three phase power line in place of the image current transformer (leakage circuit breaker having a thermal stability by receiving an operating voltage from the current transformer) The purpose is to provide.

도 1 종래 기술에 따른 모터 콘트롤러 개략도.1 is a schematic view of a motor controller according to the prior art.

도 2 본 발명에 따른 디지털 모터 콘트롤러 개략도.2 is a schematic diagram of a digital motor controller according to the present invention.

도면의 주요부분에 대한 부호의 설명Explanation of symbols for main parts of the drawings

101 : 변류기 103 : 정류회로101: current transformer 103: rectifier circuit

105 : 마이크로프로세서 107 : 트립코일105: microprocessor 107: trip coil

109 : 싸이리스트109: Cylist

상기의 목적을 달성하기 위하여 본 발명의 누전 차단기는 R, S, T 각 상의 전력선에 각각 설치되어 각 상의 누전전류를 검출하기 위한 변류기와, 상기 각 상에 설치된 변류기의 2차측 전류를 전압으로 변환하기 위한 정류회로와, 상기 정류회로에서 변환된 전압 레벨을 기 설정 레벨과 비교/판단하여 제어신호를 출력하는 마이크로프로세서와, 상기 마이크로프로세서의 제어에 의해 구동되는 트립코일을 포함하는 것을 특징으로 한다.In order to achieve the above object, the earth leakage breaker of the present invention is installed in each of the power lines of R, S, and T phases, and a current transformer for detecting the leakage current of each phase, and the secondary current of the current transformers installed in each phase are converted into voltages. And a microprocessor for outputting a control signal by comparing / determining a voltage level converted by the rectifier circuit with a preset level, and a trip coil driven by the control of the microprocessor. .

본 발명의 누전 차단기는 R,S,T의 3 상중에 어느 상의 변화에서도 누전차단기의 전자회로부가 구동될 수 있도록 상기 R,S,T 각각의 전력선에 설치된 복수개의변류기를 이용하여 누전차단기의 전자회로부의 열적 안정화를 이룰 수 있기 때문에 누전차단기 전자회로의 신뢰성을 향상시키고 누전전류에 의한 화재 및 인명피해를 줄일 수 있다.The earth leakage breaker of the present invention uses the plurality of current transformers installed on the power lines of the R, S, and T circuits so that the electronic circuit portion of the earth leakage circuit breaker can be driven in any of three phases of R, S, and T. Since thermal stabilization of the circuit part can be achieved, it is possible to improve the reliability of the circuit breaker electronic circuit and to reduce the fire and damage caused by the leakage current.

이하, 도면을 참조하여 본 발명의 누전 차단기에 대하여 설명한다.Hereinafter, the earth leakage breaker of the present invention will be described with reference to the drawings.

도 2는 본 발명의 누전차단기의 개략적 회로도이다.2 is a schematic circuit diagram of the earth leakage breaker of the present invention.

도 2에서와 같이, 본 발명의 누전차단기는 전자회로부의 구동전압을 공급하고 누전전류를 검출하기 위해 R,S,T 3 상의 전력선에 각각 복수개가 설치되고 2차측 전류를 유도하기 위한 변류기(Current Transformer)(101)와, 상기 변류기(101)에 의해 출력된 전류를 전압 강하시키기 위한 정류회로(103)와, 상기 정류회로(103)의 출력신호를 받아 전류값을 비교/판단하여 제어신호를 출력하는 마이크로프로세서(105)와, 상기 마이크로프로세서(105)의 제어에 의해 구동되는 트립코일(107)을 포함하여 구성된다.As shown in FIG. 2, the circuit breaker of the present invention is provided with a plurality of current transformers for supplying the driving voltage of the electronic circuit unit and a plurality of power lines on the R, S, and T 3 phases to detect the current leakage (Current). Transformer 101, a rectifier circuit 103 for voltage dropping the current output by the current transformer 101, and an output signal of the rectifier circuit 103 to receive and compare / determine a current value to generate a control signal. The output includes a microprocessor 105 and a trip coil 107 driven by the control of the microprocessor 105.

도시하지는 않았지만, 상기 마이크로프로세서(105)의 정확한 비교/판단을 돕기 위해 상기 정류회로(103)와 상기 마이크로프로세서(105)의 사이에 상기 정류회로(103)의 출력신호를 증폭하는 증폭회로와, 상기 정류회로의 출력신호를 디지털신호로 변환시키기 위한 A/D 변환기(Convert)를 더 포함하여 구성된다.Although not shown, an amplifying circuit for amplifying an output signal of the rectifying circuit 103 between the rectifying circuit 103 and the microprocessor 105 in order to facilitate accurate comparison / determination of the microprocessor 105; And an A / D converter for converting the output signal of the rectifier circuit into a digital signal.

또한, 상기 마이크로프로세서(105)를 제어하기 위해 사용자가 직접 정격감도전류 및 시간지연을 설정하는 특성설정부와, 상기 마이크로프로세서(105)로부터 상기 트립코일을 제어하기 위해 싸이리스트(109)를 더 포함하여 구성된다.In addition, a characteristic setting unit for setting a rated sensitivity current and a time delay directly by the user to control the microprocessor 105, and a cylist 109 to control the trip coil from the microprocessor 105 is further added. It is configured to include.

이와 같이 구성된 본 발명의 누전차단기의 동작을 설명하면 다음과 같다.Referring to the operation of the earth leakage breaker of the present invention configured as described above is as follows.

먼저, 누전이 발생할 경우 변류기(101)의 2 차측 전류로 누전차단기의 전자 회로부 구동전압 및 누전전류를 검출되고, 상기 변류기(101)의 2 차측 전류는 정류회로(103)를 거쳐 전압으로 변환된다.First, when a short circuit occurs, an electronic circuit driving voltage and a short circuit current of the circuit breaker are detected as secondary currents of the current transformer 101, and the secondary currents of the current transformer 101 are converted into voltages through the rectifier circuit 103. .

또한, 상기 정류회로(103)에서 출력된 신호는 증폭기와, A/D 변환기를 통하여 증폭 변환되고, 상기 마이크로프로세서(105)에서 전류값을 비교하여 누전전류의 발생으로 인한 트립신호를 출력하여 트립코일(107)을 동작시킨다.In addition, the signal output from the rectifier circuit 103 is amplified and converted by an amplifier and an A / D converter, and compares the current value in the microprocessor 105 to output a trip signal due to the generation of a short circuit current, and trips. The coil 107 is operated.

따라서, 이와 같은 본 발명의 누전 차단기는 전자회로부의 구동 전압을 R,S,T 각각의 2차측 전류를 유도하는 변류기(101) 사용하기 때문에 상기 전자 회로부의 열적 안정화를 이루어 누전차단기 전자회로의 신뢰성을 향상시켜 누전전류에 의한 화재 및 인명피해의 문제를 해소할 수 있다.Therefore, the earth leakage breaker of the present invention uses the current transformer 101 which induces secondary current of each of the R, S, and T driving voltages of the electronic circuit part, thereby achieving thermal stabilization of the electronic circuit part, thereby improving reliability of the circuit breaker electronic circuit. It is possible to solve the problem of fire and human injury caused by leakage current.

이상 상술한 바와 같이, 본 발명의 누전차단기는 다음과 같은 효과가 있다.As described above, the earth leakage breaker of the present invention has the following effects.

본 발명의 누전차단기는 R,S,T 각상의 변류기의 출력 전류를 이용하여 누전차단기의 전자회로부를 구동시키므로 누전차단기의 전자회로부의 신뢰성을 향상시켜 부하 및 선로의 누전발생시 누전 전류에 의한 피해를 최소화 할 수 있다.The earth leakage breaker of the present invention drives the electronic circuit portion of the earth leakage breaker by using the output currents of the current transformers of R, S, and T phases, thereby improving the reliability of the electronic circuit portion of the earth leakage breaker, thereby preventing damage caused by the earth leakage current when a short circuit occurs in the load and the line. It can be minimized.

Claims (4)

R, S, T 각 상의 전력선에 각각 설치되어 각 상의 누전전류를 검출하기 위한 변류기와,Current transformers are installed on the power lines of each of the R, S, and T phases to detect a leakage current of each phase; 상기 각 상에 설치된 변류기의 2차측 전류를 전압으로 변환하기 위한 정류회로와,A rectifier circuit for converting the secondary current of the current transformer provided in each phase into a voltage; 상기 정류회로에서 변환된 전압 레벨을 기 설정 레벨과 비교/판단하여 제어신호를 출력하는 마이크로프로세서와,A microprocessor for outputting a control signal by comparing / determining the voltage level converted in the rectifier circuit with a preset level; 상기 마이크로프로세서의 제어에 의해 구동되는 트립코일을 포함하는 것을 특징으로 하는 누전 차단기.And a trip coil driven by the control of the microprocessor. 제 1 항에 있어서,The method of claim 1, 상기 정류회로에서 변환된 전압 레벨을 증폭하기 위한 증폭기와,An amplifier for amplifying the voltage level converted in the rectifier circuit; 상기 증폭기에서 증폭된 전압 레벨을 디지털 신호로 변환하기 위한 A/D 변환기를 더 구비하는 것을 특징으로 하는 누전 차단기.And an A / D converter for converting the voltage level amplified by the amplifier into a digital signal. 제 1 항에 있어서, 상기 마이크로프로세서를 사용자에 의해 제어하기 위한 특성설정부를 더 구비하는 것을 특징으로 하는 누전 차단기.The earth leakage breaker of claim 1, further comprising a property setting unit for controlling the microprocessor by a user. 제 1 항에 있어서, 상기 마이크로프로세서로부터 상기 트립코일을 제어하기 위해 싸이리스터를 더 구비하는 것을 특징으로 하는 누전 차단기.2. The circuit breaker of claim 1, further comprising a thyristor for controlling the trip coil from the microprocessor.
KR10-2002-0007971A 2002-02-14 2002-02-14 A Circuit Breaker for electric leakage KR100469370B1 (en)

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Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01133517A (en) * 1987-11-17 1989-05-25 Toshiba Corp Detection circuit for disconnection of transmission or distribution line
JPH04105510A (en) * 1990-08-22 1992-04-07 Omron Corp Composite protective relay
JPH04339277A (en) * 1991-05-16 1992-11-26 Matsushita Electric Ind Co Ltd Accident detection device of distribution line
JPH05276648A (en) * 1992-03-25 1993-10-22 Fuji Electric Co Ltd Wiring method of test terminal for bus protective relay
KR930024244A (en) * 1992-05-19 1993-12-22 김회수 Relay automatic inspection method and device
JPH0686451A (en) * 1992-08-31 1994-03-25 Chubu Electric Power Co Inc Protective relay device for power transmission and distribution system
KR960006173U (en) * 1994-07-26 1996-02-17 이종구 Overload relay
KR960019375A (en) * 1994-11-11 1996-06-17 김호 Earth leakage breaker with instantaneous overcurrent detection
KR20000007816A (en) * 1998-07-07 2000-02-07 이종수 Apparatus and method of detecting current leakage interruption

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01133517A (en) * 1987-11-17 1989-05-25 Toshiba Corp Detection circuit for disconnection of transmission or distribution line
JPH04105510A (en) * 1990-08-22 1992-04-07 Omron Corp Composite protective relay
JPH04339277A (en) * 1991-05-16 1992-11-26 Matsushita Electric Ind Co Ltd Accident detection device of distribution line
JPH05276648A (en) * 1992-03-25 1993-10-22 Fuji Electric Co Ltd Wiring method of test terminal for bus protective relay
KR930024244A (en) * 1992-05-19 1993-12-22 김회수 Relay automatic inspection method and device
JPH0686451A (en) * 1992-08-31 1994-03-25 Chubu Electric Power Co Inc Protective relay device for power transmission and distribution system
KR960006173U (en) * 1994-07-26 1996-02-17 이종구 Overload relay
KR960019375A (en) * 1994-11-11 1996-06-17 김호 Earth leakage breaker with instantaneous overcurrent detection
KR20000007816A (en) * 1998-07-07 2000-02-07 이종수 Apparatus and method of detecting current leakage interruption

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