CN107942242A - High-voltage AC breaker Characteristics Detection evaluation method based on arc extinguishing electromagnetic waveforms - Google Patents
High-voltage AC breaker Characteristics Detection evaluation method based on arc extinguishing electromagnetic waveforms Download PDFInfo
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- CN107942242A CN107942242A CN201710989099.6A CN201710989099A CN107942242A CN 107942242 A CN107942242 A CN 107942242A CN 201710989099 A CN201710989099 A CN 201710989099A CN 107942242 A CN107942242 A CN 107942242A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
- G01R31/3271—Testing of circuit interrupters, switches or circuit-breakers of high voltage or medium voltage devices
- G01R31/3272—Apparatus, systems or circuits therefor
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- General Physics & Mathematics (AREA)
- Arc-Extinguishing Devices That Are Switches (AREA)
Abstract
The invention discloses a kind of high-voltage AC breaker Characteristics Detection evaluation method based on arc extinguishing electromagnetic waveforms, solves the technical barrier detected in real time to the arc quenching characteristic of AC circuit breaker.Running high-voltage AC breaker, during cut-offfing and closing, the electric current between dynamic and static contact increases sharply, a mutation magnetic field can be produced in space, the magnetic field then excite one mutation electric field, the electric field after and excitation one mutation magnetic field, an electromagnetic wave signal is inspired in space；The present invention is detected the electromagnetic wave signal using radio frequency sensor, when breaker arc extinguishing hydraulic performance decline, its arc extinguishing speed also declines, in AC circuit breaker interrupting process, multiple electromagnetic wave signals can be excited, the arc extinction performance of AC circuit breaker can be evaluated by the quantity and duration for the electromagnetic wave signal tested in interrupting process.Present apparatus measurement accuracy is very high, up to nanosecond, far above the precision of existing 0.01 millisecond of stroke method.
Description
Technical field
The invention belongs to high-voltage appliance switch field, more particularly to a kind of super-pressure or breaker in extra high voltage arc quenching characteristic inspection
Survey evaluation method.
Background technology
High-voltage AC breaker is one of important equipment in electric system, and the work of control and protection is played in operation of power networks
With its operating characteristics directly influences the stability of Operation of Electric Systems and the reliability of power supply.How to high-voltage alternating open circuit
The working status of device carries out effective detection and periodically evaluation, finds the early defect of breaker in time, prevents switch explosion etc.
The generation of serious accident, has important practical significance.Arc quenching characteristic is the most important performance of high-voltage circuitbreaker, AC circuit breaker
The decline of arc extinguishing ability can cause major accident, substantial amounts of the AC circuit breaker in power grid, and the prior art goes out it
Arc property cannot carry out effectively check and evaluation.At present, the detection method of high-voltage AC breaker has stroke method and electric life method.
Stroke method is mainly to measure the stroke characteristic of high-voltage circuitbreaker, can directly reflect the branch wire time and speed characteristics of breaker,
But this method can not realize on-line checking；Need to have a power failure equipment during detection, test interval length, data deficiency continuity can not
The change of reflection switch performance in time；In addition, detection is two terminated line of each port in breaker, will also be in the operation control of switch
Wiring in circuit processed, for large-scale multi-break high-voltage circuitbreaker, wiring point is more, it is necessary to operation of ascending a height, in operation
Substation, this operating method security risk is too big.Electric life method is to install current sensor additional on-board the circuit breaker, and detection is cut-off
The virtual value of electric current, the electric life that breaker is calculated after adding up is weighted with open and close times, so that indirectly to its arc quenching characteristic
It is detected and assesses；But this method can only reflect the general morphologictrend of breaker arc extinguishing characteristic, it can not reflect open circuit in real time
The mutation arc quenching characteristic of device.
The content of the invention
The present invention provides a kind of high-voltage AC breaker Characteristics Detection evaluation method based on arc extinguishing electromagnetic waveforms, solves
The technical barrier detected in real time to the arc quenching characteristic of AC circuit breaker.
The present invention is to solve above technical problem by the following technical programs：
The present general inventive concept is：Running high-voltage AC breaker, during cut-offfing and closing, between dynamic and static contact
Electric current increase sharply, can be produced in space one mutation magnetic field, the magnetic field then excite one mutation electric field, the electric field is then
The magnetic field of a mutation is excited again, and an electromagnetic wave signal is inspired in space；The present invention is using radio frequency sensor to the electromagnetism
Ripple signal is detected, and when breaker arc extinguishing hydraulic performance decline, its arc extinguishing speed also declines, in AC circuit breaker interrupting process
In, multiple electromagnetic wave signals can be excited, quantity that can be by the electromagnetic wave signal tested in interrupting process and duration pair
The arc extinction performance of AC circuit breaker is evaluated.
A kind of high-voltage AC breaker arc quenching characteristic detection device, including high-voltage AC breaker arc-chutes, are handed in high pressure
Static contact and moving contact are provided with stream arc-extinguishing chamber of circuit breaker, moving contact is linked together by touch spring and insulated tension pole,
The other end of insulated tension pole links together with operating mechanism, and radio frequency biography is provided with the side of high-voltage AC breaker arc-chutes
Sensor, radio frequency sensor are linked together by signal amplifier and high-speed oscilloscope.When moving contact and static contact contacting and
Separated moment, electric arc is produced in arc-chutes, which then excites generation electromagnetic wave signal, should by radio frequency sensor collection
Electromagnetic wave signal, amplifies through signal amplifier, and the electromagnetic wave signal is obtained using high-speed oscilloscope.
A kind of high-voltage AC breaker Characteristics Detection evaluation method based on arc extinguishing electromagnetic waveforms, it is characterised in that following step
Suddenly：
The first step, in the side of high-voltage AC breaker arc-chutes set radio frequency sensor, and radio frequency sensor amplified by signal
Device links together with high-speed oscilloscope；
Second step, by radio frequency sensor be detected high-voltage AC breaker arc-chutes surrounding space environment, to empty around
Between environmental externality interference signal recorded；
3rd step, when high-voltage circuitbreaker carries out point, closing operation when, pass through radio frequency sensor and gather high-voltage AC breaker fracture
The radiated electromagnetic wave signal at place；
4th step, the radiated electromagnetic wave signal according to the high-voltage AC breaker incision position collected, carry out high-voltage circuitbreaker
Fault type differentiates, comprises the following steps that：
If the radiated electromagnetic wave signal waveform of high-voltage AC breaker incision position A, collected is there are multiple mountain peaks, dynamic and static
There occurs closing rebound phenomenon for contact；
If the radiated electromagnetic wave signal waveform duration of high-voltage AC breaker incision position B, collected more than 1-1.5 seconds,
Then there occurs bite phenomenon for operating mechanism；
If the radiated electromagnetic wave signal waveform of high-voltage AC breaker incision position C, collected is a lasting arc waveform,
That is radiated electromagnetic wave signal exists always, then combined floodgate incomplete phenomena occurs for dynamic and static contact；
If the initial time of the three-phase radiated electromagnetic wave signal waveform of high-voltage AC breaker incision position D, collected is different,
There is the dynamic and static inconsistent phenomenon of contact switching synchronization of three-phase.
Compared with traditional high-voltage circuitbreaker kinetic characteristic measurement evaluation method, first, sensor of the invention and open circuit
Device body is not required to make breaker body any change without machinery and electrical link, measurement,, can be just without wiring without having a power failure
Prompt carry out on-line measurement；Secondly, present apparatus measurement accuracy is very high, up to nanosecond, far above existing 0.01 millisecond of stroke method
Precision；Finally, the arc quenching characteristic during breaker being cut-off and be closed at the same time is assessed.
Brief description of the drawings
Fig. 1 is the radiated electromagnetic wave signal acquisition structure schematic diagram of the present invention；
Fig. 2 is the radiated electromagnetic wave signal acquisition structure schematic diagram of split-phase type high-voltage circuitbreaker；
Fig. 3 is high-voltage circuitbreaker radiated electromagnetic wave signal during divide-shut brake under normal circumstances；
Fig. 4 is the radiated electromagnetic wave signal during high voltage circuit breaker closing when closing rebound failure occurs for dynamic/static contact；
Fig. 5 is the radiated electromagnetic wave signal during high voltage circuit breaker closing when jam faults occur for operating mechanism；
Fig. 6 is the radiated electromagnetic wave signal during high voltage circuit breaker closing when dynamic/static contact closes a floodgate failure not in place；
Fig. 7 is the radiated electromagnetic wave signal during high voltage circuit breaker closing when three-phase dynamic/static contact switching synchronization is inconsistent.
Embodiment
The present invention is described in detail below in conjunction with the accompanying drawings：
A kind of high-voltage AC breaker Characteristics Detection evaluation method based on arc extinguishing electromagnetic waveforms, is following steps：
The first step, in the side of high-voltage AC breaker arc-chutes 5 set radio frequency sensor 1, and radio frequency sensor 1 put by signal
Big device 2 links together with high-speed oscilloscope 3；
Second step, by radio frequency sensor 1 be detected 5 surrounding space environment of high-voltage AC breaker arc-chutes, to surrounding
Space environment external interference signals are recorded；
3rd step, when high-voltage circuitbreaker carries out point, closing operation when, high-voltage AC breaker is gathered by radio frequency sensor 1 and is broken
Radiated electromagnetic wave signal at mouthful；
4th step, the radiated electromagnetic wave signal according to the high-voltage AC breaker incision position collected, carry out high-voltage circuitbreaker
Fault type differentiates, comprises the following steps that：
If the radiated electromagnetic wave signal waveform of high-voltage AC breaker incision position A, collected is there are multiple mountain peaks, dynamic and static
There occurs closing rebound phenomenon for contact；
If the radiated electromagnetic wave signal waveform duration of high-voltage AC breaker incision position B, collected more than 1-1.5 seconds,
Then there occurs bite phenomenon for operating mechanism；
If the radiated electromagnetic wave signal waveform of high-voltage AC breaker incision position C, collected is a lasting arc waveform,
That is radiated electromagnetic wave signal exists always, then combined floodgate incomplete phenomena occurs for dynamic and static contact；
If the initial time of the three-phase radiated electromagnetic wave signal waveform of high-voltage AC breaker incision position D, collected is different,
There is the dynamic and static inconsistent phenomenon of contact switching synchronization of three-phase.
First, three radio frequency sensors are connected with signal amplifier, signal amplifier is connected with high-speed oscilloscope；It will penetrate
Video sensor is directed at equipment under test surrounding space, and the background environment of equipment under test is detected, excludes external interference signals
Influence；Then, three radio frequency sensors are directed at A, B, C three-phase fracture, when high-voltage circuitbreaker carries out breaking-closing operating, passed through
High-speed oscilloscope can measure high-voltage circuitbreaker radiated electromagnetic wave signal；Analysis judges high-voltage circuitbreaker during breaking-closing operating
The electromagnetic wave signal of generation, if being no different regular signal, judges that the High Voltage Circuit Breaker Condition is good, waveform is as shown in Figure 3；If
There is abnormal signal, it is necessary to judge the different fault type of high-voltage circuitbreaker, specific determination methods are as follows：
（1）When closing rebound failure occurs for dynamic/static contact：When closing rebound occurs for dynamic/static contact, generation is multiple between dynamic/static contact
Restrike phenomenon, i.e., when dynamic/static contact closes arc extinction, dynamic/static contact flicks electric arc generation, therefore, the electromagnetic wave signal of radiation
Multiple peak values are had, waveform is as shown in Figure 4；
（2）When jam faults occur for operating mechanism：When bite problem occurs for operating mechanism, the motion process of mechanism is not smooth enough,
Compare under normal circumstances, the duration of the electromagnetic wave signal of radiation is longer, and waveform is as shown in Figure 5；
（3）When dynamic/static contact combined floodgate failure not in place：When dynamic/static contact combined floodgate failure not in place occurs, dynamic/static contact is due to failing
Close, then produce a lasting electric arc, that is, the electromagnetic wave signal radiated exists always, and waveform is as shown in Figure 6；
（4）When three-phase dynamic/static contact switching synchronization is inconsistent：When three-phase dynamic/static contact closes a floodgate the not same period, i.e. A, B, C three-phase
The Time Inconsistency that dynamic/static contact closes a floodgate, then the time of generation electric arc is also inconsistent between dynamic/static contact, therefore radiated electromagnetic wave is believed
Number initial time it is different, waveform is as shown in Figure 7；
Upon completion of the assays, the electromagnetic wave signal of detection is preserved by high-speed oscilloscope, to carry out next step data
Analysis.
Claims (1)
- A kind of 1. high-voltage AC breaker Characteristics Detection evaluation method based on arc extinguishing electromagnetic waveforms, it is characterised in that following step Suddenly：The first step, in high-voltage AC breaker arc-chutes（5）Side set radio frequency sensor（1）, radio frequency sensor（1）Pass through Signal amplifier（2）With high-speed oscilloscope（3）Link together；Second step, pass through radio frequency sensor（1）To high-voltage AC breaker arc-chutes（5）Surrounding space environment is detected, right Surrounding space environmental externality interference signal is recorded；3rd step, when high-voltage circuitbreaker carries out point, closing operation when, pass through radio frequency sensor（1）Gather high-voltage AC breaker The radiated electromagnetic wave signal of incision position；4th step, the radiated electromagnetic wave signal according to the high-voltage AC breaker incision position collected, carry out high-voltage circuitbreaker Fault type differentiates, comprises the following steps that：If the radiated electromagnetic wave signal waveform of high-voltage AC breaker incision position A, collected is there are multiple mountain peaks, dynamic and static There occurs closing rebound phenomenon for contact；If the radiated electromagnetic wave signal waveform duration of high-voltage AC breaker incision position B, collected more than 1-1.5 seconds, Then there occurs bite phenomenon for operating mechanism；If the radiated electromagnetic wave signal waveform of high-voltage AC breaker incision position C, collected is a lasting arc waveform, That is radiated electromagnetic wave signal exists always, then combined floodgate incomplete phenomena occurs for dynamic and static contact；If the initial time of the three-phase radiated electromagnetic wave signal waveform of high-voltage AC breaker incision position D, collected is different, There is the dynamic and static inconsistent phenomenon of contact switching synchronization of three-phase.
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108983085A (en) * | 2018-08-27 | 2018-12-11 | 国网河南省电力公司电力科学研究院 | A kind of circuit breaker electric magnetostatic wave signal three-phase acquisition device and three-phase separation method |
| CN110045273A (en) * | 2019-03-26 | 2019-07-23 | 四川大学 | A kind of SF6Contact of breaker ablation degree on-line monitoring method |
| CN110888051A (en) * | 2019-11-16 | 2020-03-17 | 国网辽宁省电力有限公司电力科学研究院 | Novel detect double antenna electromagnetic wave collection of circuit breaker arc extinguishing characteristic device |
| CN111142015A (en) * | 2018-11-06 | 2020-05-12 | 西门子股份公司 | Monitoring method and monitoring circuit for state of contact of switch device |
| CN111142017A (en) * | 2020-01-03 | 2020-05-12 | 国网江苏省电力有限公司检修分公司 | Breaker state diagnosis system and method |
| CN111638445A (en) * | 2020-04-21 | 2020-09-08 | 国网山东省电力公司青岛供电公司 | SF6 circuit breaker arc extinguishing performance detection method and system |
| CN111679181A (en) * | 2020-06-19 | 2020-09-18 | 国网陕西省电力公司电力科学研究院 | Live detection method and device for ablation of high-voltage reactive switching switch contact |
| CN113311321A (en) * | 2021-05-27 | 2021-08-27 | 云南电网有限责任公司电力科学研究院 | Method for detecting three-phase arc extinguishing performance of circuit breaker based on separation algorithm |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111142015A (en) * | 2018-11-06 | 2020-05-12 | 西门子股份公司 | Monitoring method and monitoring circuit for state of contact of switch device |
| CN110045273A (en) * | 2019-03-26 | 2019-07-23 | 四川大学 | A kind of SF6Contact of breaker ablation degree on-line monitoring method |
| CN110045273B (en) * | 2019-03-26 | 2021-04-30 | 四川大学 | SF (sulfur hexafluoride)6Online monitoring method for ablation degree of breaker contact |
| CN110888051A (en) * | 2019-11-16 | 2020-03-17 | 国网辽宁省电力有限公司电力科学研究院 | Novel detect double antenna electromagnetic wave collection of circuit breaker arc extinguishing characteristic device |
| CN111142017A (en) * | 2020-01-03 | 2020-05-12 | 国网江苏省电力有限公司检修分公司 | Breaker state diagnosis system and method |
| CN111638445A (en) * | 2020-04-21 | 2020-09-08 | 国网山东省电力公司青岛供电公司 | SF6 circuit breaker arc extinguishing performance detection method and system |
| CN111679181A (en) * | 2020-06-19 | 2020-09-18 | 国网陕西省电力公司电力科学研究院 | Live detection method and device for ablation of high-voltage reactive switching switch contact |
| CN113311321A (en) * | 2021-05-27 | 2021-08-27 | 云南电网有限责任公司电力科学研究院 | Method for detecting three-phase arc extinguishing performance of circuit breaker based on separation algorithm |
| CN113311321B (en) * | 2021-05-27 | 2023-06-23 | 云南电网有限责任公司电力科学研究院 | Method for detecting three-phase arc extinguishing performance of circuit breaker based on separation algorithm |
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Application publication date: 20180420 |