CN103545785A - Power supply MOV surge protection device failure fault current cyclic wave monitoring device and method - Google Patents

Power supply MOV surge protection device failure fault current cyclic wave monitoring device and method Download PDF

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Publication number
CN103545785A
CN103545785A CN201310513114.1A CN201310513114A CN103545785A CN 103545785 A CN103545785 A CN 103545785A CN 201310513114 A CN201310513114 A CN 201310513114A CN 103545785 A CN103545785 A CN 103545785A
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China
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module
pulse
protection device
lightning protection
signal
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CN201310513114.1A
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Chinese (zh)
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CN103545785B (en
Inventor
毛协国
李正元
伍先德
孙中梁
陈伟
刘余平
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上海臻和防雷电气技术有限责任公司
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Abstract

The invention relates to a power supply MOV surge protection device failure fault current cyclic wave monitoring device. The power supply MOV surge protection device failure fault current cyclic wave monitoring device is characterized in that the device comprises a surge protection device grounding current detection sensor, the surge protection device grounding current detection sensor is connected with a signal filtering amplifying module in series, the signal filtering amplifying module is then connected with a pulse forming module in series, the output end of the pulse forming module is divided into two circuits, one of the circuits is connected with a pulse stepping counting module through a timing reset gate module, the other circuit is directly connected with the pulse stepping counting module, and the pulse forming module is connected with a breaker releasing driving module. According to the other technical scheme, the invention further provides a power supply MOV surge protection device failure fault current cyclic wave monitoring method achieved through the device. According to the power supply MOV surge protection device failure fault current cyclic wave monitoring device and method, the two mutually-constrained protection technology requirements that damage of the power frequency fault continuous small current caused by power supply transient overvoltage to an SPD is stopped, and it is ensured that no misoperation is produced under the lightning shock large current so that the SPD can be separated from a power grid are met.

Description

Power supply MOV lightning protection device failure of removal electric current cycle monitoring device and method

Technical field

The present invention relates to a kind of new application in power supply MOV lightning protection device inefficacy on-line monitoring and lightning protection device front end protective device and guard method, belong to power frequency supply lightning protection device resist technology field.

Background technology

Lightning protection device is called again Surge Protector (being designated hereinafter simply as SPD) and is widely used in all trades and professions of national economy.For being equipped with more in the power-supply device of distribution, including oxidation piezo-resistance (being designated hereinafter simply as MOV) lightning protection for power supply, by difference need to be connected across power frequency supply alternate and over the ground between (L-L, L-N, L-PE, N-PE); Bear the thunder-strike current of releasing, suppressing the middle overvoltage surge of electrical network and occur, improving quality of power supply, the safe operation vital task of protective device equipment.

But along with lightning protection device extensively and in every field, use for a long time, SPD self burns initiation fire accident and lightning Protection lost efficacy continuously problem day by day highlights, and causes serious economic loss to country and enterprise.

SPD self burns the fire incident of initiation, through scene textual criticism with analyze, commonly at electrical network, occurs overvoltage fault moment, and this type of power network overvoltage is different from moment lightning strike induction voltage, continues generation, Infinite Energy, is that SPD cannot absorb elimination.Once surpass the maximum operation of SPD continuous voltage, the MOV that will accelerate SPD is deteriorated, cause power frequency fault current and continue, by SPD, to make the impaired heating of SPD, when serious, will there is burnout failure, lead to disaster.

Continuous lightning Protection failure accidents easily sees lightning protection device and surprisingly departs from protected power network line, electrical network is lost Lightning Over-voltage, thunder-strike current are carried out to the unit protection of pressure limiting earial drainage, causes equipment personal injury to occur.

For this reason; in lightning protection standard, require lightning protection for power supply to apply preposition fuse or circuit breaker is realized front end overcurrent protection; can when appearring in lightning protection device, rigid sustained short-circuit fault cut off rapidly and being connected of power circuit; avoid power-supply system protection switch to occur overstep tripping, cause large area blackout.Front end overcurrent protective device also should be able to be blocked power supply transien overvoltage initiation power frequency fault continuous current simultaneously, and Accident prevention expands.

But in actual applications, conventional lightning protection for power supply front end overcurrent protective device is difficult to take into account the defencive function of realizing above-mentioned two aspects: fuse or circuit breaker that lightning protection for power supply front end overcurrent protective device is used, and conventionally protect settings all can excise the rigid sustained short-circuit fault of SPD; But when appearring in power-supply system, abnormal line voltage raises, cause SPD to start sub-conducting, during the continuous current of the power frequency breaking down, metering function due to the sub-conducting resistance of SPD, source current does not often reach the fast shut-off value of front end overcurrent protective device fuse or circuit breaker, and the power failure current energy of continuity is enough to cause the overheated catching fire of SPD; In addition as the protection quick-break electric current settings of fuse or circuit breaker are turned down, when meeting the continuous current drop-away value of power frequency of fault, the impulse current of thunderbolt can cause protective device quick-break again, is that SPD departs from electrical network, the fault that causes follow-up lightning Protection to lose efficacy.Above-mentioned situation is set in awkward ground front end overcurrent protective device setting value.

Summary of the invention

An object of the present invention is to provide a kind of SPD of guaranteeing safe operation, stop the device that SPD incidents of spontaneous combustion occurs.Another object of the present invention is to provide a kind of method that adopts said apparatus.

In order to achieve the above object, a technical scheme of the present invention has been to provide a kind of power supply MOV lightning protection device failure of removal electric current cycle monitoring device, it is characterized in that: comprise that access lightning protection device group grounded circuit is in order to the lightning protection device checking for grounded current transducer of monitoring grounding leakage current, lightning protection device checking for grounded current transducer serial connection signal filtering amplification module, signal filtering amplification module is connected in series pulse shaping module again, the ground connection leakage current being obtained according to lightning protection device checking for grounded current transducer by pulse shaping module produces pulse signal, the output of pulse shaping module is divided into two-way, one tunnel connects pulse step counting module via timing reset gate module, another road directly connects pulse step counting module, pulse shaping module connecting breaker dropout driver module, pulse step counting module is only exported trip signal to circuit breaker tripping driver module by timing reset gate module controls after the pulse shaping module pulse signal at least continuous three cycles of output being detected, by circuit breaker tripping driver module according to this trip signal control connection in the action of threading off of the lightning protection device front-end protection circuit breaker of lightning protection device group front end.

Preferably, described timing reset gate module selects delayer to realize; Described pulse step counting module selects reducible pulse step counter to realize, and by delayer, to pulse step counter, provides reset signal.

Another technical scheme of the present invention has been to provide a kind of power supply MOV lightning protection device failure of removal electric current cycle monitoring method that adopts said apparatus, it is characterized in that, step is:

The first step, the ground connection leakage current being obtained according to lightning protection device checking for grounded current transducer by pulse shaping module produce pulse signal, wherein, when there is thunderbolt, ground connection leakage current is transient high-current signal, now, pulse shaping module produces single pulse signal; When producing the lasting little electric current of power frequency fault, ground connection leakage current is electrical network power frequency fault current, and now, pulse shaping module produces the power frequency pulse signal of electrical network power frequency rule, and the cycle of this power frequency pulse signal is T 1=1/ electrical network work frequency;

Second step, select delayer to realize the timing gate module that resets, the delay duration of this delayer is T 2, T 2>=N * T 1n is not less than 3 positive integer, select reducible pulse step counter to realize pulse step counting module, this pulse step counter is set as counting at least 2 and at the most after the pulse signal of N-1 consecutive periods, to circuit breaker tripping driver module output trip signal;

Timing reset gate module is synchronizeed with pulse step counting module and first pulse of pulse signal detected, and timing reset gate module starts timing, and meanwhile, pulse step counting module starts to detect the consecutive periods number of pulse signal; If pulse shaping module produces single pulse signal, pulse step counting module only can detect a pulse period, and timing reset gate module is reaching the delay duration T of setting 2backward pulse step counter provides reset signal, and the input of next pulse signal is waited in pulse step counter O reset again;

If pulse shaping module produces power frequency pulse signal, pulse step counting module is detecting continuously at least 2 and after the pulse signal in N-1 cycle, to circuit breaker tripping driver module, export trip signal at the most, now, timing reset gate module does not also reach the delay duration T of setting 2, by circuit breaker tripping driver module according to this trip signal control connection in the action of threading off of the lightning protection device front-end protection circuit breaker of lightning protection device group front end.

Preferably, in second step, the value of described N is defined as and is not less than 3 and be not more than 5 positive integer.

The present invention uses step-by-step counting technology; electric current to the SPD that flows through is screened; the larger pulse current of moment passing through for aperiodicity Lightning Over-voltage shields; and consecutive periods is counted by the fault power frequency small electric stream of SPD; once reaching shutter value (3~5 recurrent pulse) makes an immediate response; output dropout actuating signal, guarantees SPD safe operation, stops the generation of SPD incidents of spontaneous combustion.

The present invention can meet the lasting little electric current of blocking-up power supply transien overvoltage initiation power frequency fault SPD is endangered; guarantee that again not misoperation makes SPD depart from the resist technology requirement of two kinds of mutual restriction demands of electrical network under thunderbolt heavy impulse current, realize the lightning protection device front-end protection technology that possesses omnibearing protection function.

Accompanying drawing explanation

Fig. 1 is the system block diagram of a kind of power supply MOV lightning protection device failure of removal electric current cycle monitoring device provided by the invention.

Embodiment

For the present invention is become apparent, hereby with preferred embodiment, and coordinate accompanying drawing to be described in detail below.

As shown in Figure 1, lightning protection device group SPD is generally via lightning protection device front-end protection circuit breaker DK1 access electrical network, and a kind of power supply MOV lightning protection device failure of removal electric current cycle monitoring device provided by the invention comprises that access lightning protection device group SPD grounded circuit is in order to the lightning protection device checking for grounded current transducer MC4 of monitoring grounding leakage current, lightning protection device checking for grounded current transducer MC4 serial connection signal filtering amplification module KDV1, signal filtering amplification module KDV1 is connected in series pulse shaping module MC1 again, the ground connection leakage current being obtained according to lightning protection device checking for grounded current transducer MC4 by pulse shaping module MC1 produces pulse signal, the output of pulse shaping module MC1 is divided into two-way, one tunnel connects pulse step counting module MB1 via timing reset gate module TDR1, another road directly connects pulse step counting module MB1, pulse shaping module MC1 connecting breaker dropout driver module DK01, pulse step counting module MB1 is only controlled and to circuit breaker tripping driver module DK01, exported trip signal after the pulse shaping module MC1 pulse signal at least continuous three cycles of output being detected by timing reset gate module TDR1, by circuit breaker tripping driver module DK01 according to this trip signal control connection in the lightning protection device front-end protection circuit breaker DK1 of the lightning protection device group SPD front end action of threading off.

Wherein, timing reset gate module TDR1 selects delayer to realize; Described pulse step counting module MB1 selects reducible pulse step counter to realize, and by delayer, to pulse step counter, provides reset signal.

In the present embodiment, the work frequency of electrical network is 50Hz.The present invention also provides a kind of power supply MOV lightning protection device failure of removal electric current cycle monitoring method that adopts said apparatus, the steps include:

The first step, the ground connection leakage current being obtained according to lightning protection device checking for grounded current transducer MC4 by pulse shaping module MC1 produce pulse signal, wherein, when there is thunderbolt, ground connection leakage current is transient high-current signal, now, pulse shaping module MC1 produces single pulse signal; When producing the lasting little electric current of power frequency fault, ground connection leakage current is electrical network power frequency fault current, and now, pulse shaping module MC1 produces the power frequency pulse signal of electrical network power frequency rule, and the cycle of this power frequency pulse signal is T 1=20ms;

Second step, select delayer to realize the timing gate module TDR1 that resets, the delay duration of this delayer is T 2, T 2=5 * 20=100ms, select reducible pulse step counter to realize pulse step counting module MB1, this pulse step counter is set as counting on after the pulse signal of 3-4 consecutive periods, to circuit breaker tripping driver module DK01 output trip signal;

Timing reset gate module TDR1 is synchronizeed with pulse step counting module MB1 and first pulse of pulse signal detected, and timing reset gate module TDR1 starts timing, and meanwhile, pulse step counting module MB1 starts to detect the consecutive periods number of pulse signal; If pulse shaping module MC1 produces single pulse signal, pulse step counting module MB1 only can detect a pulse period, and timing reset gate module TDR1 is reaching the delay duration T of setting 2backward pulse step counter provides reset signal, and the input of next pulse signal is waited in pulse step counter O reset again;

If pulse shaping module MC1 produces power frequency pulse signal, pulse step counting module MB1 exports trip signal to circuit breaker tripping driver module DK01 after the pulse signal that a continuous 3-4 consecutive periods detected, now, timing reset gate module TDR1 does not also reach the delay duration T of setting 2, by circuit breaker tripping driver module DK01 according to this trip signal control connection in the lightning protection device front-end protection circuit breaker DK1 of the lightning protection device group SPD front end action of threading off, complete lightning protection device group SPD intelligent front end defencive function.

The present invention produces after fault power frequency leakage current when monitoring lightning protection device MOV inefficacy, can be limited in response action in 3-5 power supply cycle phase, drives lightning protection device front-end protection switch immediately to thread off, and prevents fault expansion; Simultaneously application specific electronic module can be differentiated and shield lightning protection device and when being struck by lightning, pass through tens of kiloampere pulse currents of MOV and not misoperation; Guarantee the normal stable lightning protection function of lightning protection device of non-defective unit MOV.

Claims (4)

1. a power supply MOV lightning protection device failure of removal electric current cycle monitoring device, it is characterized in that: comprise that access lightning protection device group (SPD) grounded circuit is in order to the lightning protection device checking for grounded current transducer (MC4) of monitoring grounding leakage current, lightning protection device checking for grounded current transducer (MC4) serial connection signal filtering amplification module (KDV1), signal filtering amplification module (KDV1) is connected in series pulse shaping module (MC1) again, the ground connection leakage current being obtained according to lightning protection device checking for grounded current transducer (MC4) by pulse shaping module (MC1) produces pulse signal, the output of pulse shaping module (MC1) is divided into two-way, one tunnel connects pulse step counting module (MB1) via timing reset gate module (TDR1), another road directly connects pulse step counting module (MB1), pulse shaping module (MC1) connecting breaker dropout driver module (DK01), pulse step counting module (MB1) is only controlled and the backward circuit breaker tripping driver module of pulse signal (DK01) the output trip signal in pulse shaping module (MC1) at least continuous three cycles of output detected by timing reset gate module (TDR1), by circuit breaker tripping driver module (DK01) according to this trip signal control connection in the action of threading off of the lightning protection device front-end protection circuit breaker (DK1) of lightning protection device group (SPD) front end.
2. a kind of power supply MOV lightning protection device failure of removal electric current cycle monitoring device as claimed in claim 1, is characterized in that: described timing reset gate module (TDR1) selects delayer to realize; Described pulse step counting module (MB1) selects reducible pulse step counter to realize, and by delayer, to pulse step counter, provides reset signal.
3. the power supply MOV lightning protection device failure of removal electric current cycle monitoring method that employing is installed as claimed in claim 1, is characterized in that, step is:
The first step, the ground connection leakage current being obtained according to lightning protection device checking for grounded current transducer (MC4) by pulse shaping module (MC1) produce pulse signal, wherein, when there is thunderbolt, ground connection leakage current is transient high-current signal, now, pulse shaping module (MC1) produces single pulse signal; When producing the lasting little electric current of power frequency fault, ground connection leakage current is electrical network power frequency fault current, and now, pulse shaping module (MC1) produces the power frequency pulse signal of electrical network power frequency rule, and the cycle of this power frequency pulse signal is T 1=1/ electrical network work frequency;
Second step, select delayer to realize the timing gate module (TDR1) that resets, the delay duration of this delayer is T 2, T 2>=N * T 1n is not less than 3 positive integer, select reducible pulse step counter to realize pulse step counting module (MB1), this pulse step counter is set as counting at least 2 and at the most after the pulse signal of N-1 consecutive periods, to circuit breaker tripping driver module (DK01) output trip signal;
Timing reset gate module (TDR1) is synchronizeed with pulse step counting module (MB1) and first pulse of pulse signal detected, timing reset gate module (TDR1) starts timing, meanwhile, pulse step counting module (MB1) starts to detect the consecutive periods number of pulse signal; If pulse shaping module (MC1) produces single pulse signal, pulse step counting module (MB1) only can detect a pulse period, and timing reset gate module (TDR1) is reaching the delay duration T of setting 2backward pulse step counter provides reset signal, and the input of next pulse signal is waited in pulse step counter O reset again;
If pulse shaping module (MC1) produces power frequency pulse signal, pulse step counting module (MB1) is detecting continuously at least 2 and after the pulse signal in N-1 cycle, to circuit breaker tripping driver module (DK01), export trip signal at the most, now, timing reset gate module (TDR1) does not also reach the delay duration T of setting 2, by circuit breaker tripping driver module (DK01) according to this trip signal control connection in the action of threading off of the lightning protection device front-end protection circuit breaker (DK1) of lightning protection device group (SPD) front end.
4. if any a kind of power supply MOV lightning protection device failure of removal electric current cycle monitoring method claimed in claim 3, it is characterized in that, in second step, the value of described N is defined as and is not less than 3 and be not more than 5 positive integer.
CN201310513114.1A 2013-10-25 2013-10-25 Power supply MOV lightning protection device failure of removal electric current cycle monitoring device and method CN103545785B (en)

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CN104485655A (en) * 2014-12-31 2015-04-01 湖南华宽通科技股份有限公司 Lighting prevention device and method for counting number of lightning strokes on lighting prevention device
CN106329504A (en) * 2015-06-30 2017-01-11 施耐德电器工业公司 Backup protection circuit breaker of surge protector and application method of backup protection circuit breaker
CN106356805A (en) * 2016-08-22 2017-01-25 陈宜中 Method for endowing shortcircuit burning self-cut-off device with air switch hot stripping function
CN107546725A (en) * 2017-08-11 2018-01-05 上海空间电源研究所 A kind of spacecraft discharge circuit overvoltage protective system

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CN104485655A (en) * 2014-12-31 2015-04-01 湖南华宽通科技股份有限公司 Lighting prevention device and method for counting number of lightning strokes on lighting prevention device
CN106329504A (en) * 2015-06-30 2017-01-11 施耐德电器工业公司 Backup protection circuit breaker of surge protector and application method of backup protection circuit breaker
CN106356805A (en) * 2016-08-22 2017-01-25 陈宜中 Method for endowing shortcircuit burning self-cut-off device with air switch hot stripping function
CN107546725A (en) * 2017-08-11 2018-01-05 上海空间电源研究所 A kind of spacecraft discharge circuit overvoltage protective system
CN107546725B (en) * 2017-08-11 2019-04-12 上海空间电源研究所 A kind of spacecraft discharge circuit overvoltage protective system

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