CN113054624A - Special breaker for intelligent low-voltage surge protector and control method thereof - Google Patents

Special breaker for intelligent low-voltage surge protector and control method thereof Download PDF

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Publication number
CN113054624A
CN113054624A CN202110505470.3A CN202110505470A CN113054624A CN 113054624 A CN113054624 A CN 113054624A CN 202110505470 A CN202110505470 A CN 202110505470A CN 113054624 A CN113054624 A CN 113054624A
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CN
China
Prior art keywords
spd
alarm
processing unit
central processing
current collector
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Pending
Application number
CN202110505470.3A
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Chinese (zh)
Inventor
张家浩
翁利国
李国庆
余彬
张凯
林桢雨
刘琳
朱双双
施凌震
赵军
陈红极
孔锋峰
朱渭杨
练德强
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.)
Hangzhou Power Supply Co of State Grid Zhejiang Electric Power Co Ltd
Zhejiang Zhongxin Electric Power Engineering Construction Co Ltd
Original Assignee
Hangzhou Power Supply Co of State Grid Zhejiang Electric Power Co Ltd
Zhejiang Zhongxin Electric Power Engineering Construction Co Ltd
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.)
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Publication date
Application filed by Hangzhou Power Supply Co of State Grid Zhejiang Electric Power Co Ltd, Zhejiang Zhongxin Electric Power Engineering Construction Co Ltd filed Critical Hangzhou Power Supply Co of State Grid Zhejiang Electric Power Co Ltd
Priority to CN202110505470.3A priority Critical patent/CN113054624A/en
Publication of CN113054624A publication Critical patent/CN113054624A/en
Pending legal-status Critical Current

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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02HEMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H7/00Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
    • H02H7/008Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for protective arrangements according to this subclass
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01DMEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D21/00Measuring or testing not otherwise provided for
    • G01D21/02Measuring two or more variables by means not covered by a single other subclass
    • 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
    • H02H3/04Details with warning or supervision in addition to disconnection, e.g. for indicating that protective apparatus has functioned

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Emergency Protection Circuit Devices (AREA)

Abstract

The invention discloses a special circuit breaker for an intelligent low-voltage surge protector and a control method thereof, wherein the special circuit breaker comprises a shell, a SPD and an upper computer, a communication interface is arranged at the top of the shell, a main control circuit board is arranged in the shell, a release is arranged on the right side of the main control circuit board, a temperature collector socket is arranged at the bottom of the shell, a current collector socket is arranged beside the temperature collector socket, a temperature collector is connected to the temperature collector socket and is close to the SPD, the current collector is connected to the current collector socket and is connected with the SPD in series, a data wire is connected to the communication interface, and the other end of the data wire is electrically connected with the upper computer. The invention has the advantages of high safety, strong stability, good economic benefit and the like.

Description

Special breaker for intelligent low-voltage surge protector and control method thereof
Technical Field
The invention relates to the field of breaker structures, in particular to a breaker special for an intelligent low-voltage surge protector and a control method thereof.
Background
The low-voltage distribution system is connected with a large number of electronic instruments and meters and information equipment in a bearing way, and the circuit of the low-voltage distribution system is struck by lightning to cause transient overvoltage, so that the low-voltage distribution system is an important factor for causing the faults of the instruments and meters and the information equipment. The surge protector SPD can suppress transient overvoltage caused by lightning stroke, and is a protection device which is necessary to be equipped in a low-voltage distribution system.
However, in practical use, due to field complexity, such as voltage fluctuation of the power system, unexpected lightning activity or technical quality defects of the product, deterioration and failure of the surge protector SPD are caused, so that heating fire, short-circuit explosion accident or false operation protection failure caused by broken wires and breakage of the surge protector SPD is caused, and therefore a protection device needs to be provided for operation of the surge protector SPD.
The most widely used surge protector SPD core component is a zinc oxide powder pressed ceramic body nonlinear varistor MOV mounted in a plastic insulating base and connected between the phase line L and the earth line PE of the low voltage distribution system by wire or via a "disconnector". The surge protector SPD is high impedance under normal power grid voltage, the leakage current is less than 1mA in resistance, but is low impedance when the power grid is struck by lightning and generates transient overvoltage, the lightning current is discharged to limit overvoltage, and when the power grid is electrically fluctuated and generates transient overvoltage, the surge protector SPD can bear fault current, so that the surge protector SPD generates abnormal heat and is damaged.
Disclosure of Invention
The invention provides a special breaker for an intelligent low-voltage surge protector, which has the advantages of good safety, high stability and the like, and aims to solve the problems that the traditional surge protector SPD is easy to degrade or fault current caused by transient overvoltage of a power grid and the like.
The invention discloses a special circuit breaker for an intelligent low-voltage surge protector and a control method thereof, wherein the special circuit breaker comprises a shell, a SPD and an upper computer, a communication interface is arranged at the top of the shell, a main control circuit board is arranged in the shell, a release is arranged on the right side of the main control circuit board, a temperature collector socket is arranged at the bottom of the shell, a current collector socket is arranged beside the temperature collector socket, a temperature collector is connected to the temperature collector socket and is close to the SPD, the current collector is connected to the current collector socket and is connected with the SPD in series, a data wire is connected to the communication interface, and the other end of the data wire is electrically connected with the upper computer.
Preferably, the master control circuit board is provided with a power supply, a central processing unit and an operational amplifier chip, the communication interface is electrically connected with a signal transmission end of the central processing unit, a power supply end of the central processing unit and a power supply end of the operational amplifier chip are respectively electrically connected with the power supply, a signal receiving end of the central processing unit is electrically connected with an output end of the operational amplifier chip, an input end of the operational amplifier chip is respectively electrically connected with a temperature collector socket and a current collector socket, and a control end of the release is electrically connected with a signal transmission end of the central processing unit.
Preferably, the output end of the central processing unit is provided with an alarm, the alarm comprises an alarm lamp and a loudspeaker, the left end and the right end of the alarm lamp are respectively electrically connected with the two I/O ports on the central processing unit, and the alarm lamp is connected with the loudspeaker in parallel.
The control method comprises the following steps:
1. at the initial stage of SPD operation, when the current collector gathered resistive leakage current 1 mA-10 mA, SPD normal operating this moment, central processing unit can control the alarm and report to the police this moment, and the alarm lamp is green this moment.
At the initial stage of the operation of the SPD, the resistive leakage current is below 1 milliamp in a normal power grid, and because the zinc oxide resistor of the SPD has a parasitic capacitance document 1 of several microfarads, when the SPD is operated in a low-voltage power grid of 50Hz220V, a capacitive current I =2 pi fU of several milliamps is generated, generally within 10 milliamps, which is a normal leakage current. If the current tends to zero, the SPD can be judged to quit the operation, the alarm is controlled, and operation and maintenance personnel are prompted to overhaul in time.
2. When the current collector collects that the resistive leakage current is less than 0.5mA, the SPD can be judged to quit the operation, the central processing unit can control the alarm to give an alarm, and the alarm lamp is purple and prompts operation and maintenance personnel to overhaul in time through the horn.
3. At the middle stage of SPD operation, when the current collector collects 10 mA-100 mA of resistive leakage current, the central processing unit controls the alarm to give an alarm, and the alarm lamp is yellow and prompts operation and maintenance personnel to overhaul in time through the horn.
In the middle stage of the operation of the SPD, the SPD maintains normal operation through voltage aging, thermal aging and leakage current increase to tens of milliamperes to hundreds of milliamperes depending on the quality level of various products, but the leakage current may cause tripping due to the influence of the leakage current. Therefore, whether the section is set at the early warning point or not is determined according to the operation requirement of the power grid.
4. At the later stage of SPD operation, when the current collector collects 10 mA-100 mA of resistive leakage current, the central processing unit controls the alarm to give an alarm, and the alarm lamp is red and prompts an operation and maintenance person to replace an SPD device through the loudspeaker.
In the late period of SPD operation, the critical deterioration state is in, and the leakage current is hundreds of milliamperes to 1 ampere. The SPD can still maintain operation, but the power consumption is increased by P = IU, namely the operation cost is increased, and the central processing unit sends an early warning signal to prompt operation and maintenance personnel to replace the SPD device.
When leakage currents of more than 1 ampere are detected, the SPD has irreversible deterioration or the power grid has transient overvoltage, and the fault current can cause the SPD to generate heat seriously to cause the plastic base of the SPD to melt or burn. The central processor drives the breaker to open according to the preset inverse time-lag ampere-second characteristic such as 10 A.S, and gives an alarm.
If the fault current is reduced in the operation time of the inverse time limit action, the transient overvoltage of the power grid disappears, and the SPD still keeps operating.
The setting of the inverse time limit characteristic also avoids the false operation when the SPD relives the lightning current, and improves the operation reliability.
When the SPD is in lightning strike current with the performance larger than rated discharge current, breakdown short circuit and explosion accidents can happen, or short circuit accidents happen to circuits below the circuit breaker due to other reasons, the clapper type instantaneous release directly drives the circuit breaker to open the brake, cuts off the power supply and gives an alarm.
The thermistor directly detects the operating temperature of the SPD, and the thermistor is not only related to leakage current, but also influenced by the ambient temperature, fluctuation of the voltage of a power grid and heat accumulation influence of leakage current change, so that the thermistor more visually reflects the heating state of the SPD. When the temperature of 105 ℃ is detected, the central processing unit drives the breaker to open and send out an alarm.
The core component of the central processing unit of the intelligent breaker special for the surge protector is an N76E003AT20 type central processing unit CPU, the central processing unit CPU is powered by an auxiliary power supply module, a current signal and a temperature signal are input into the CPU through an amplifier, when the signal multiple strength reaches a set threshold value, a trip coil is used for driving the breaker to open a brake, and an indicator light and a buzzer are driven to give out audible and visual alarm or early warning.
The communication module built in the central processor can be connected with a management network of a low-voltage power distribution system through an R485 interface, and transmits current and temperature information, early warning and alarming double numbers to an upper computer, so that operation and maintenance personnel and management personnel can visually know the whole operation period of the SPD, the whole-process information is prevented in advance, various faults are processed in time, and the management mode of the SPD operation is consistent with that of the low-voltage power distribution automatic management system.
The invention has the following beneficial effects:
the main circuit of the circuit breaker adopts a straight-through conductor structure to be used as a special SPD protection device, and the impedance of a lightning stroke discharge loop of the circuit breaker is not increased, so that the performance of the circuit breaker is not influenced.
For the deterioration and heating of main faults in the SPD operation, the double measures of fault current monitoring and heating temperature monitoring are adopted, so that the occurrence of heating combustion accidents can be prevented and directly stopped in advance. The operation safety is improved.
The newly-added SPD open-circuit state monitoring function can effectively prevent false operation, reduce the risk of lightning damage to the low-voltage power distribution system and equipment carried by the low-voltage power distribution system, and improve the safety of the system.
By the fault acousto-optic alarm early warning function, operation and maintenance personnel can timely differentiate SPD operation faults, and the operation reliability is improved.
The communication function of the circuit breaker is connected with the existing low-voltage distribution management network, so that the circuit breaker SPD is monitored by the management platform, the operation reliability is further improved, and the workload of on-site inspection of operation and maintenance personnel can be reduced. The intelligent development trend of electric products is met.
Meanwhile, the uploaded SPD leakage current data can be used for knowing the operation power consumption of the SPD, high-energy-consumption operation in the degradation process is avoided, energy can be saved, consumption can be reduced, and direct economic benefits can be generated.
Drawings
FIG. 1 is a block diagram of the system of the present invention.
Fig. 2 is a schematic view of the mounting structure of the present invention.
Fig. 3 is a schematic structural diagram of the present invention.
Casing 1, SPD2, host computer 3, master control circuit board 4, release 5, temperature collector socket 6, electric current collector socket 7, temperature collector 8, electric current collector 9, power 10, central processing unit 11, fortune chip 12, communication interface 13, alarm lamp 14, loudspeaker 15.
Detailed Description
The technical scheme of the invention is further specifically described by the following embodiments and the accompanying drawings.
Example (b): further explained according to fig. 1, fig. 2 and fig. 3, the circuit breaker special for the intelligent low-voltage surge protector and the control method thereof of the embodiment include a housing 1, an SPD2 and an upper computer 3, wherein a communication interface 13 is arranged at the top of the housing 1, a main control circuit board 4 is arranged in the housing 1, a release 5 is arranged on the right side of the main control circuit board 4, a temperature collector socket 6 is arranged at the bottom of the housing 1, a current collector socket 7 is arranged beside the temperature collector socket 6, a temperature collector 8 is connected to the temperature collector socket 6 and is close to the SPD2, a current collector 9 is connected to the current collector socket 7 and is connected in series with the current collector 9 and the SPD2, a data wire is connected to the communication interface 13, and the other end of the data wire is electrically connected with the upper computer 3.
The main control circuit board 4 on be equipped with power 10, central processing unit 11 and operational amplifier chip 12, communication interface 13 and central processing unit 11's signal transmission end electric connection, central processing unit 11's power 10 end and operational amplifier chip 12's power 10 end respectively with power 10 electric connection, central processing unit 11's signal receiving terminal and operational amplifier chip 12's output electric connection, operational amplifier chip 12's input respectively with temperature collector socket 6 and current collector socket 7 electric connection, release 5's control end and central processing unit 11's signal transmission end electric connection.
The output of central processing unit 11 on be equipped with the siren, the siren include alarm lamp 14 and loudspeaker 15, alarm lamp 14 about both ends respectively with two IO mouth electric connection on the central processing unit 11, alarm lamp 14 and loudspeaker 15 parallel connection.
The control method of the invention comprises the following steps:
1. at the initial stage of the SPD2, when the current collector 9 collects resistive leakage current 1 mA-10 mA, the SPD2 normally operates, the central processing unit 11 controls the alarm to give an alarm, and the alarm lamp 14 is green.
2. When the current collector 9 collects that the resistive leakage current is less than 0.5mA, the SPD2 can be judged to quit the operation, the central processing unit 11 can control the alarm to give an alarm, and the alarm lamp 14 is purple and prompts operation and maintenance personnel to overhaul in time through the loudspeaker 15.
3. At the middle stage of the operation of SPD2, when the current collector 9 collects the resistive leakage current of 10 mA-100 mA, the central processing unit 11 controls the alarm to give an alarm, and the alarm lamp 14 is yellow and prompts the operation and maintenance personnel to overhaul in time through the horn 15.
4. At the later stage of the operation of the SPD2, when the current collector 9 collects 10 mA-100 mA of resistive leakage current, the central processing unit 11 controls the alarm to give an alarm, and the alarm lamp 14 is red and prompts an operation and maintenance person to replace an SPD2 device through the loudspeaker 15.
The above description is only an embodiment of the present invention, but the structural features of the present invention are not limited thereto, and any changes or modifications within the scope of the present invention by those skilled in the art are covered by the present invention.

Claims (4)

1. A breaker special for an intelligent low-voltage surge protector comprises a shell (1), an SPD (surge protection device) (2) and an upper computer (3), it is characterized in that the top of the shell (1) is provided with a communication interface (13), a main control circuit board (4) is arranged in the shell (1), a release (5) is arranged on the right side of the main control circuit board (4), a temperature collector socket (6) is arranged at the bottom of the shell (1), a current collector socket (7) is arranged beside the temperature collector socket (6), a temperature collector (8) is connected to the socket (6) of the temperature collector and the temperature collector (8) is close to the SPD (2), a current collector (9) is connected to the current collector socket (7) and the current collector (9) is connected with the SPD (2) in series, a data line is connected to the communication interface (13), and the other end of the data line is electrically connected with the upper computer (3).
2. The special circuit breaker for the intelligent low-voltage surge protector according to claim 1, wherein, the main control circuit board (4) is provided with a power supply (10), a central processing unit (11) and an operational amplifier chip (12), the communication interface (13) is electrically connected with the signal transmission end of the central processing unit (11), the power supply (10) end of the central processing unit (11) and the power supply (10) end of the operational amplifier chip (12) are respectively electrically connected with the power supply (10), the signal receiving end of the central processing unit (11) is electrically connected with the output end of the operational amplifier chip (12), the input end of the operational amplifier chip (12) is respectively and electrically connected with the temperature collector socket (6) and the current collector socket (7), and the control end of the release (5) is electrically connected with the signal transmission end of the central processing unit (11).
3. The circuit breaker special for the intelligent low-voltage surge protector according to claim 1, wherein an alarm is arranged on the output end of the central processing unit (11), the alarm comprises an alarm lamp (14) and a horn (15), the left end and the right end of the alarm lamp (14) are electrically connected with two I/O ports on the central processing unit (11), and the alarm lamp (14) is connected with the horn (15) in parallel.
4. An intelligent circuit breaker control method for low-voltage surge protectors, which is suitable for the intelligent circuit breaker for low-voltage surge protectors as claimed in claim 1, and is characterized in that the control method comprises the following steps:
at the initial stage of putting the SPD (2) into operation, when the current collector (9) collects 1 mA-10 mA of resistive leakage current, the SPD (2) normally operates, the central processing unit (11) controls the alarm to give an alarm, and the alarm lamp (14) is green;
when the current collector (9) collects that the resistive leakage current is less than 0.5mA, the SPD (2) can be judged to quit the operation, the central processing unit (11) can control the alarm to give an alarm, and the alarm lamp (14) is purple and prompts operation and maintenance personnel to overhaul in time through the loudspeaker (15);
in the middle stage of the operation of the SPD (2), when the current collector (9) collects 10 mA-100 mA of resistive leakage current, the central processing unit (11) controls the alarm to give an alarm, and the alarm lamp (14) is yellow and prompts operation and maintenance personnel to overhaul in time through the loudspeaker (15);
at the later stage of the operation of the SPD (2), when the current collector (9) collects 10 mA-100 mA of resistive leakage current, the central processing unit (11) controls the alarm to give an alarm, and the alarm lamp (14) is red and prompts operation and maintenance personnel to replace an SPD (2) device through the loudspeaker (15).
CN202110505470.3A 2021-05-10 2021-05-10 Special breaker for intelligent low-voltage surge protector and control method thereof Pending CN113054624A (en)

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CN202110505470.3A CN113054624A (en) 2021-05-10 2021-05-10 Special breaker for intelligent low-voltage surge protector and control method thereof

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Application Number Priority Date Filing Date Title
CN202110505470.3A CN113054624A (en) 2021-05-10 2021-05-10 Special breaker for intelligent low-voltage surge protector and control method thereof

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116304646A (en) * 2023-05-18 2023-06-23 杭州易龙防雷科技有限公司 Intelligent control method and device of surge protector and electronic equipment

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101789590A (en) * 2009-01-22 2010-07-28 孙巍巍 Novel surge protective device
CN103715652A (en) * 2014-01-13 2014-04-09 上海万谱电器有限公司 Intelligent backup protection disconnecting device for surge protection devices
CN104267305A (en) * 2014-09-25 2015-01-07 深圳市科威电子测试有限公司 Method and system for judging deterioration degree of surge protective device (SPD)
CN104280631A (en) * 2014-09-28 2015-01-14 深圳市科威电子测试有限公司 SPD online intelligent monitoring device and SPD online intelligent monitoring system
CN211905534U (en) * 2019-11-22 2020-11-10 贵州电网有限责任公司 Lightning arrester on-line monitoring remote transmission system
CN215934468U (en) * 2021-05-10 2022-03-01 杭州恺哥体育设施工程有限公司 Special circuit breaker of intelligent low pressure surge protector

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101789590A (en) * 2009-01-22 2010-07-28 孙巍巍 Novel surge protective device
CN103715652A (en) * 2014-01-13 2014-04-09 上海万谱电器有限公司 Intelligent backup protection disconnecting device for surge protection devices
CN104267305A (en) * 2014-09-25 2015-01-07 深圳市科威电子测试有限公司 Method and system for judging deterioration degree of surge protective device (SPD)
CN104280631A (en) * 2014-09-28 2015-01-14 深圳市科威电子测试有限公司 SPD online intelligent monitoring device and SPD online intelligent monitoring system
CN211905534U (en) * 2019-11-22 2020-11-10 贵州电网有限责任公司 Lightning arrester on-line monitoring remote transmission system
CN215934468U (en) * 2021-05-10 2022-03-01 杭州恺哥体育设施工程有限公司 Special circuit breaker of intelligent low pressure surge protector

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116304646A (en) * 2023-05-18 2023-06-23 杭州易龙防雷科技有限公司 Intelligent control method and device of surge protector and electronic equipment
CN116304646B (en) * 2023-05-18 2023-10-10 杭州易龙防雷科技有限公司 Intelligent control method and device of surge protector and electronic equipment

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