CN106356811A - Circuit breaker with faulted neutral line and default phase protection function - Google Patents

Circuit breaker with faulted neutral line and default phase protection function Download PDF

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Publication number
CN106356811A
CN106356811A CN201610968632.6A CN201610968632A CN106356811A CN 106356811 A CN106356811 A CN 106356811A CN 201610968632 A CN201610968632 A CN 201610968632A CN 106356811 A CN106356811 A CN 106356811A
Authority
CN
China
Prior art keywords
phase
zero line
open
diode
detecting module
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201610968632.6A
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Chinese (zh)
Inventor
张利亭
梁志刚
左建峰
岳光太
周兴飞
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ZHANGJIAKOU POWER SUPPLY COMPANY STATE GRID JIBEI ELECTRIC POWER Co Ltd
State Grid Corp of China SGCC
Original Assignee
ZHANGJIAKOU POWER SUPPLY COMPANY STATE GRID JIBEI ELECTRIC POWER Co Ltd
State Grid Corp of China SGCC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ZHANGJIAKOU POWER SUPPLY COMPANY STATE GRID JIBEI ELECTRIC POWER Co Ltd, State Grid Corp of China SGCC filed Critical ZHANGJIAKOU POWER SUPPLY COMPANY STATE GRID JIBEI ELECTRIC POWER Co Ltd
Priority to CN201610968632.6A priority Critical patent/CN106356811A/en
Publication of CN106356811A publication Critical patent/CN106356811A/en
Pending legal-status Critical Current

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Classifications

    • 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

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  • Emergency Protection Circuit Devices (AREA)

Abstract

The invention discloses a circuit breaker with a faulted neutral line and default phase protection function. The circuit breaker is an upgraded technology for an existing three-phase residual-current circuit breaker, and a faulted neutral line and default phase fault detection module is added on the basis of an existing three-phase residual-current circuit breaker. The circuit breaker disclosed by the invention is simple in structure and low in cost, not only reserves the original overload, short circuit and earth leakage protection functions but also increases a protection function of a faulted neutral line and default phase fault on a three-phase load circuit. The circuit breaker disclosed by the invention is used for protecting a three-phase four-wire load circuit of a low voltage power distribution network in real time.

Description

With chopper off zero and default-phase protection function
Technical field
The present invention relates to a kind of Multifunctional breaker, for the real-time guard of low-voltage network three-phase and four-line load circuit, Specifically a kind of with chopper off zero and default-phase protection function.
Background technology
In low-voltage network zero line break, the voltage on three-phase load circuit understands serious unbalance, so results in part Voltage on electric equipment raises suddenly, leads to a large amount of household electrical appliance of resident to burn, and causes serious economic damage;Same with this When, after zero line break, the zero line voltage-to-ground of three-phase load circuit side is also no longer zero, and this is possible to make some be abutted against zero guarantor Dangerous voltage on the electric equipment band of shield, seriously threatens user's personal safety;In addition, low-voltage network open-phase fault also when have Occur, the threephase asynchronous in phase-deficient operation, rotating speed can drastically decline, thus causing motor overheating, if after phase shortage Can not cut off the electricity supply in time, motor will burn;Further, will also result in the increase suddenly of neutral line current while phase shortage, from And the safe operation to zero line constitutes a threat to.As can be seen here, either zero line break, or phase-deficient operation, if can not cut in time Power-off source, its consequence is extremely serious.But occur to this time interval of cutting off the electricity supply to require extremely short, this process from fault Can be automatically performed by the controlling organization of circuit.With regard to current low-voltage network using various general chopper situation from the point of view of, Existing various there is zero line break and the circuit breaker design of open-phase protection is relative complex, cost of manufacture is higher.
Content of the invention
In order to solve above-mentioned technical problem present in prior art, the present invention is intended to provide a kind of band is off zero and phase shortage is protected The chopper of protective function, to upgrade to existing three-phase and four-line RCCB, it is to break in highly developed electric leakage One zero line break and open-phase fault detecting module are loaded on the device of road, and takes easy docking, upgraded to work(more than one Energy chopper, to reduce the development cost of new technique, shortens the construction cycle, makes full use of the ripe dropout of current RCCB Technology, makes the unfailing performance of the Multifunctional breaker after upgrading access guarantee.
The present invention for achieving the above object, is achieved through the following technical solutions:
A kind of with chopper off zero and default-phase protection function, it includes trip switch, trip switch first contact, trip switch Second contact, trip switch the 3rd contact, tripping coil, current signal amplify and tripping coil drive circuit, current transformer, Zero line break and open-phase fault detecting module;
Zero line break and open-phase fault detecting module are used for zero line break, the detecting and be that current signal amplifies and de- of open-phase fault The work of button coil driver provides power supply.It is electrodeless that described zero line break and open-phase fault detecting module include the first~the 3rd Electric capacity, the first~the 6th diode, the first current-limiting resistance and the second current-limiting resistance;Wherein:
The parameter of the first~the 3rd electrodeless electric capacity is consistent;
First~the 6th diode composition three-phase bridge rectifier circuit, zero line break and open-phase fault detecting module have three inputs End;
The anode of described first diode, the 3rd diode and the 5th diode, connects zero line break and phase shortage event correspondingly One of input of barrier detecting module;First diode, the 3rd diode and the negative electrode of the 5th diode link together, The positive output end as zero line break and open-phase fault detecting module after the second current-limiting resistance current limliting;
The negative electrode of described second diode, the 4th diode and the 6th diode, connects zero line break respectively and open-phase fault detects Three inputs of module;Second diode, the 4th diode and the anode of the 6th diode link together, and break as zero line Road and the negative output terminal of open-phase fault detecting module;
The respective one end of three electrodeless electric capacities, connects in zero line break and the input of open-phase fault detecting module correspondingly One;The respective other end of three electrodeless electric capacities links together, after the first current-limiting resistance current limliting, as zero line break and The neutral sampling outfan of open-phase fault detecting module;
Three inputs of zero line break and open-phase fault detecting module connect trip switch first contact, trip switch respectively Two contacts, the corresponding phase line of the lower edge of a knife of trip switch the 3rd contact;Zero line break and the neutrality of open-phase fault detecting module After sampling outfan passes through the magnet ring of current transformer, it is connected with zero line output end;
The positive output end of zero line break and open-phase fault detecting module is connected to current signal and amplifies and tripping coil drive circuit A control output end, current signal amplifies and another control output end of tripping coil drive circuit is connected to tripping coil One end, another terminal connecting zero line open circuit of tripping coil and negative output terminal, zero line break and the phase shortage of open-phase fault detecting module Fault-finding module, current signal amplify and tripping coil drive circuit and one series electrical closing of tripping coil composition Road;Trip switch first contact, the input of trip switch second contact, the upper edge of a knife of trip switch the 3rd contact and zero line End, as the described input with the chopper with default-phase protection function off zero, is used for being connected to three-phase four-wire power.
As the optimization of the present invention, the parameter of the described first~the 6th diode is consistent.
The present invention due to employing above-mentioned structure, its compared with prior art, acquired technological progress is:
(1) present invention is the upgrading to existing three-phase and four-line RCCB, disconnected in highly developed three-phase and four-line electric leakage Load one " zero line break and open-phase fault detecting module " on the device of road and take the docking of simplicity, the modular structure letter of increase Single, low cost;
(2) present invention not only remains original overload, short circuit, creepage protection function, also add generation zero line break simultaneously Or the defencive function to three-phase and four-line load circuit during open-phase fault.
The present invention is used for carrying out real-time guard to low-voltage network three-phase and four-line load circuit.
Brief description
Accompanying drawing is used for providing a further understanding of the present invention, and constitutes a part for description, the reality with the present invention Apply example and be used for explaining the present invention together, be not construed as limiting the invention.
In the accompanying drawings:
Fig. 1 is zero line break and the open-phase fault detecting module circuit diagram of the embodiment of the present invention;
Fig. 2 (a) is the fault vectors figure off zero of the embodiment of the present invention;
Fig. 2 (b) is the open-phase fault vector diagram of the embodiment of the present invention;
Fig. 2 (c) is the off zero of the embodiment of the present invention and phase shortage breaks down simultaneously vector diagram;
Fig. 3 is the inside and outside wiring diagram with the chopper with default-phase protection function off zero of the embodiment of the present invention.
In figure: in, three-phase four-wire power, a1, leakage current signal processing and tripping coil control circuit, a2, zero line break And open-phase fault detecting module, l, tripping coil, x, the magnet ring of current transformer, m, three-phase and four-line load circuit, qf, dropout Switch, t1, trip switch first contact, t2, trip switch second contact, t3, trip switch the 3rd contact.
Specific embodiment
Below in conjunction with accompanying drawing, the preferred embodiments of the present invention are illustrated.It should be appreciated that preferred reality described herein Apply example to be merely to illustrate and explain the present invention, be not intended to limit the present invention.
Embodiment a kind of with chopper off zero and default-phase protection function
The present embodiment is as shown in figure 3, including trip switch qf, trip switch the first contact t1, trip switch the second contact t2, taking off Button switch the 3rd contact t3, tripping coil l, current signal amplification and tripping coil drive circuit a1, current transformer are (in figure Current transformer only gives magnet ring x), and zero line break and open-phase fault detecting module a2.
As shown in figure 1, zero line break and open-phase fault detecting module a2 include electrodeless electric capacity c1, c2, c3, also include two poles Pipe d1, d2, d3, d4, d5 and d6, also include current-limiting resistance r1 and current-limiting resistance r2.
Zero line break and open-phase fault detecting module a2 have three inputs for u1, v1 and w1.
Six diodes d1, d2, d3, d4, d5, d6 are preferably parameter identical product, and they collectively constitute three-phase bridge Rectification circuit.
In the present embodiment, current-limiting resistance r1 is common small-power resistance, and current-limiting resistance r2 adopts high-power cement electricity Resistance.
The anode of diode d1, d3, d5, meets zero line break and input u1, v1, w1 of open-phase fault detecting module a2 respectively. The negative electrode of diode d1, d3, d5 links together, as zero line break and open-phase fault detecting module a2 after current-limiting resistance r2 Positive output end+.
The negative electrode of diode d2, d4, d6, connect respectively the input u1 of zero line break and open-phase fault detecting module a2, v1, w1.The anode of diode d2, d4, d6 links together, as the negative output of zero line break and open-phase fault detecting module a2 End-.
The parameter of three electrodeless electric capacities c1, c2, c3 is consistent.The respective one end of electrodeless electric capacity c1, c2, c3 connects zero line respectively Open circuit and input u1, v1, w1 of open-phase fault detecting module a2.The respective other end of stepless electric capacity c1, c2, c3 is connected to one Rise, the neutral sampling outfan n1 as zero line break and open-phase fault detecting module a2 after current-limiting resistance r1.
As shown in figure 3, the inside of the present embodiment, by the input u1 of zero line break and open-phase fault detecting module a2, v1, W1 connects circuit breaker tripping respectively and switchs the first contact t1 of qf, the second contact t2, the corresponding phase of the lower edge of a knife of the 3rd contact t3 Line u2, v2, w2, neutral sampling outfan n1 is connected with zero line output end n2 through after the magnet ring x of current transformer.
The positive output end of zero line break and open-phase fault detecting module a2+be connected to current signal amplification and tripping coil drive One control output end of galvanic electricity road a1, current signal amplifies and another control output end of tripping coil drive circuit a1 connects To one end of tripping coil l, another terminal connecting zero line open circuit of tripping coil l and open-phase fault detecting module a2 negative output terminal-, I.e. zero line break and open-phase fault detecting module a2, current signal amplify and tripping coil drive circuit a1 and tripping coil l Three constitutes the series circuit of a closure.
The outside with the chopper with default-phase protection function off zero that the present embodiment is provided, according further to three-phase and four-line electric leakage What chopper was original connects martingale, and that is, trip switch the first contact t1, trip switch the second contact t2, trip switch the 3rd touch The upper edge of a knife of head t3 and zero line input adapter, respectively as the input of the chopper the present embodiment with off zero and default-phase protection function End, for meeting four terminals u, v, w, n of three-phase four-wire power.The outfan of the present embodiment is used for connecting three-phase and four-line load Circuit m.
The present embodiment in the case of different faults operation principle be described below:
(1) zero line of transmission line of electricity is when there is open circuit in the input side of the present embodiment
If load circuit m is asymmetric for three-phase and four-line, the current potential u of neutral point (zero line) n ' of three-phase and four-line load circuit m siden′Will Neutral point can be deviateed, and uneven degree its zero line more serious current potential un′Deviation neutral point is more remote, but the neutral sampling of a2 The current potential of point n1 is but still maintained at the position of neutral point, i.e. zero potential, and as shown in Figure 2 (a) shows, this will be between point n1 and n ' Form unbalance voltage, produce out-of-balance current in the presence of this voltage so that in n1 n ' wire, by Fig. 3 Understand that this wire is through current transformer magnet ring x in connection procedure, at this moment will be defeated in the secondary side of current transformer Go out signal, this signal amplifies through current signal and tripping coil drive circuit a1 amplifies rear-guard galvanic electricity magnetic tripping coil l, makes dropout Switch qf action, cuts off the electricity supply, three-phase and four-line load circuit m is protected.
(2) if a certain input side in the present embodiment of transmission line of electricity occurs open circuit, that is, during phase shortage
The current potential of the neutral sampled point n1 of zero line break and open-phase fault detecting module a2 will deviate neutral point, but in three-phase The current potential u of four linear load circuit m side zero linesn′Neutral point u remaining unchanged with power supply in the presence of zero linenIt is consistent, i.e. zero electricity Position, such as Fig. 2 (b), then produce out-of-balance current between n1 and n ', so in the secondary side output signal of current transformer, This signal amplifies through current signal and tripping coil drive circuit a1 amplifies rear-guard galvanic electricity magnetic tripping coil l, makes trip switch qf Action, cuts off the electricity supply and so that three-phase and four-line load circuit m is protected.
(3) zero line break and open-phase fault occur simultaneously
The current potential of the neutral sampled point n1 of zero line break and open-phase fault detecting module a2 can deviate neutrality because of open-phase fault first Point zero potential, but because the symmetry of electric capacity makes this current potential just between the midpoint of line voltage;And three-phase and four-line load The current potential u of circuit m side zero linen′Also neutral point can be deviateed because of zero line break fault, because three-phase and four-line load circuit m is not right Claim, along with the reason of phase shortage, the at this moment current potential u of three-phase and four-line load circuit m side zero linen′It is not only deviating from neutral point and meeting Deviate the midpoint of line voltage, as shown in Figure 2 (c), this has resulted in n1 and nCurrent potential unequal, then in n1 and nBetween produce Raw out-of-balance current, so in the secondary side output signal of current transformer, this signal amplifies and tripping coil through current signal Drive circuit a1 amplifies rear-guard galvanic electricity magnetic tripping coil l, makes trip switch qf action, cuts off the electricity supply and make three-phase and four-line load circuit M is protected.
Finally it is noted that the foregoing is only the preferred embodiments of the present invention, it is not limited to the present invention, Although being described in detail to the present invention with reference to the foregoing embodiments, for a person skilled in the art, it still may be used To modify to the technical scheme described in foregoing embodiments, or equivalent is carried out to wherein some technical characteristics. All any modification, equivalent substitution and improvement within the spirit and principles in the present invention, made etc., should be included in the present invention's Within protection domain.

Claims (2)

1. a kind of with chopper off zero and default-phase protection function, it include trip switch, trip switch first contact, thread off open Close the second contact, trip switch the 3rd contact, tripping coil, current signal amplification and tripping coil drive circuit, Current Mutual Inductance Device it is characterised in that: it also includes zero line break and open-phase fault detecting module, and described zero line break and open-phase fault detect mould Block includes the first~the 3rd electrodeless electric capacity, the first~the 6th diode, the first current-limiting resistance and the second current-limiting resistance;Wherein:
The parameter of the first~the 3rd electrodeless electric capacity is consistent;
First~the 6th diode composition three-phase bridge rectifier circuit, zero line break and open-phase fault detecting module have three inputs End;
The anode of described first diode, the 3rd diode and the 5th diode, connects zero line break and phase shortage event correspondingly One of input of barrier detecting module;First diode, the 3rd diode and the negative electrode of the 5th diode link together, The positive output end as zero line break and open-phase fault detecting module after the second current-limiting resistance current limliting;
The negative electrode of described second diode, the 4th diode and the 6th diode, connects zero line break respectively and open-phase fault detects Three inputs of module;Second diode, the 4th diode and the anode of the 6th diode link together, and break as zero line Road and the negative output terminal of open-phase fault detecting module;
The respective one end of three electrodeless electric capacities, connects in zero line break and the input of open-phase fault detecting module correspondingly One;The respective other end of three electrodeless electric capacities links together, after the first current-limiting resistance current limliting, as zero line break and The neutral sampling outfan of open-phase fault detecting module;
Three inputs of zero line break and open-phase fault detecting module connect trip switch first contact, trip switch respectively Two contacts, the corresponding phase line of the lower edge of a knife of trip switch the 3rd contact;Zero line break and the neutrality of open-phase fault detecting module After sampling outfan passes through the magnet ring of current transformer, it is connected with zero line output end;
The positive output end of zero line break and open-phase fault detecting module is connected to current signal and amplifies and tripping coil drive circuit A control output end, current signal amplifies and another control output end of tripping coil drive circuit is connected to tripping coil One end, another terminal connecting zero line open circuit of tripping coil and negative output terminal, zero line break and the phase shortage of open-phase fault detecting module Fault-finding module, current signal amplify and tripping coil drive circuit and one series electrical closing of tripping coil composition Road;Trip switch first contact, the input of trip switch second contact, the upper edge of a knife of trip switch the 3rd contact and zero line End, as the described input with the chopper with default-phase protection function off zero, is used for being connected to three-phase four-wire power.
2. the chopper with off zero and default-phase protection function according to claim 1 it is characterised in that: described the first~the The parameter of six diodes is consistent.
CN201610968632.6A 2016-10-27 2016-10-27 Circuit breaker with faulted neutral line and default phase protection function Pending CN106356811A (en)

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CN201610968632.6A CN106356811A (en) 2016-10-27 2016-10-27 Circuit breaker with faulted neutral line and default phase protection function

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Application Number Priority Date Filing Date Title
CN201610968632.6A CN106356811A (en) 2016-10-27 2016-10-27 Circuit breaker with faulted neutral line and default phase protection function

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112072608A (en) * 2020-09-24 2020-12-11 上海半月形机电船舶有限公司 Switch for protecting fat of three power supply appliances and design and manufacture technology

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4542433A (en) * 1983-09-01 1985-09-17 Sperry Corporation Missing phase detector
CN1264956A (en) * 2000-03-10 2000-08-30 姬金富 Multi-phase AC zero-cross rectifier and power supply phase loss monitor using it
CN101877477A (en) * 2009-05-01 2010-11-03 杨树昌 Leakage protection switch for preventing three-phase power circuit from generating high voltage
CN102891471A (en) * 2011-07-20 2013-01-23 姚福来 Three-phase circuit breaker having zero offset, zero/fire wire reverse connection and fire wire disconnection protection functions
CN103441466A (en) * 2013-08-16 2013-12-11 湛江开关有限公司 Automatic phase-failure zero-failure power-off protection device
CN204464947U (en) * 2015-02-06 2015-07-08 广东电网有限责任公司佛山禅城供电局 A kind of signal sampling device be applied on phase-defect protection circuit breaker off zero
CN206135392U (en) * 2016-10-27 2017-04-26 国网冀北电力有限公司张家口供电公司 Disconnected zero -sum in area lacks looks protect function's circuit breaker

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4542433A (en) * 1983-09-01 1985-09-17 Sperry Corporation Missing phase detector
CN1264956A (en) * 2000-03-10 2000-08-30 姬金富 Multi-phase AC zero-cross rectifier and power supply phase loss monitor using it
CN101877477A (en) * 2009-05-01 2010-11-03 杨树昌 Leakage protection switch for preventing three-phase power circuit from generating high voltage
CN102891471A (en) * 2011-07-20 2013-01-23 姚福来 Three-phase circuit breaker having zero offset, zero/fire wire reverse connection and fire wire disconnection protection functions
CN103441466A (en) * 2013-08-16 2013-12-11 湛江开关有限公司 Automatic phase-failure zero-failure power-off protection device
CN204464947U (en) * 2015-02-06 2015-07-08 广东电网有限责任公司佛山禅城供电局 A kind of signal sampling device be applied on phase-defect protection circuit breaker off zero
CN206135392U (en) * 2016-10-27 2017-04-26 国网冀北电力有限公司张家口供电公司 Disconnected zero -sum in area lacks looks protect function's circuit breaker

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112072608A (en) * 2020-09-24 2020-12-11 上海半月形机电船舶有限公司 Switch for protecting fat of three power supply appliances and design and manufacture technology

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