CN111933460A - Online evaluation method and system for failure of circuit breaker contact - Google Patents
Online evaluation method and system for failure of circuit breaker contact Download PDFInfo
- Publication number
- CN111933460A CN111933460A CN202011013758.0A CN202011013758A CN111933460A CN 111933460 A CN111933460 A CN 111933460A CN 202011013758 A CN202011013758 A CN 202011013758A CN 111933460 A CN111933460 A CN 111933460A
- Authority
- CN
- China
- Prior art keywords
- circuit breaker
- time
- arcing time
- arcing
- evaluated
- 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.)
- Granted
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H1/00—Contacts
- H01H1/0015—Means for testing or for inspecting contacts, e.g. wear indicator
Landscapes
- Arc-Extinguishing Devices That Are Switches (AREA)
- Keying Circuit Devices (AREA)
Abstract
The invention discloses a method and a system for online evaluation of contact failure of a circuit breaker, which comprises the following steps: s1: acquiring time marks of each stage when the breaker is opened; s2: calculating the actual arcing time of the breaker during opening according to the model of the breaker; s3: obtaining n-time historical brake opening data of the circuit breaker to be evaluated, and solving a calculation formula of arcing time of the circuit breaker to be evaluated through fitting; s4: when the circuit breaker to be evaluated has a new primary opening operation, the arcing time is predicted through the calculation formula of the arcing time obtained in S3; s5: and comparing the arcing time predicted by the step S4 with the actual arcing time calculated by the step S2, and judging that the contact of the circuit breaker fails when the deviation of the arcing time and the actual arcing time exceeds a threshold value. The method does not need to add any hardware equipment, and accurately calculates the arcing time, so that the final judgment is more accurate.
Description
Technical Field
The invention relates to the technical field of high-voltage circuit breakers, in particular to a method and a system for online evaluation of contact failure of a circuit breaker.
Background
After receiving a switching-off command, the high-voltage circuit breaker drives the moving contact to be separated through the operating mechanism, transitional or stable electric arcs can be formed in contact gaps at the moment, and the duration from the generation of the electric arcs to the extinguishing of the electric arcs becomes arcing time. The arcing time is the most important parameter reflecting the arc extinguishing capability of the high-voltage circuit breaker and determines whether the high-voltage circuit breaker can successfully cut off the short-circuit current.
Chinese patent publication No. 30, 08 and 2019 and publication No. CN110187263A disclose a method, device and system for evaluating contact failure based on arcing time. The method for evaluating the failure of the circuit element contact based on the arcing time comprises the following steps: receiving the currently recorded arcing time of the circuit element; comparing the currently recorded arcing time of the circuit element with the average arcing time according to a preset rule, and judging whether a contact of the circuit element enters a failure inflection point interval or not; when the contact of the circuit element enters a failure inflection point interval, alarm information is sent out. The health condition of the contact is judged by integrating the influence of various conditions (such as environment, temperature, contact abrasion, damage of high-current breaking to the contact and the like), the arcing time in the breaking process of the contact is monitored, and whether the contact enters an inflection point interval or not is judged according to the relation between the arcing time of each time and the average arcing time.
Although it is generally accepted in the industry to use arcing time as an evaluation index to measure whether a high-voltage circuit breaker contact fails, there are still unsolved problems in the practical application process: firstly, the arcing time is obtained by adopting a measuring mode, and special hardware equipment is required to be installed in both direct measurement and indirect measurement; whether the failure occurs is judged according to the relationship between the arcing time of each time and the average arcing time, but the threshold value judging method is not comprehensive and objective enough because the arcing time and the switching-off current have close relationship; and thirdly, the arcing time is obtained through a direct test or a synthetic test, the operation working condition is not involved, the arcing phenomenon also exists in the normal operation current of the high-voltage circuit breaker during operation, and the accumulated effect is not reflected in the contact failure evaluation.
Disclosure of Invention
The invention aims to provide an online evaluation method for failure of a contact of a circuit breaker, which solves the problem that the existing method for judging the failure of the contact of the circuit breaker according to arcing time is inaccurate in arcing time.
It is a further object of the present invention to provide an online evaluation system for circuit breaker contact failure.
In order to solve the technical problems, the technical scheme of the invention is as follows:
a method for online evaluation of contact failure of a circuit breaker comprises the following steps:
s1: acquiring time marks of each stage when the breaker is opened;
s2: calculating the actual arcing time of the breaker during opening according to the model of the breaker;
s3: obtaining n-time historical brake opening data of the circuit breaker to be evaluated, and solving a calculation formula of arcing time of the circuit breaker to be evaluated through fitting;
s4: when the circuit breaker to be evaluated has a new primary opening operation, the arcing time is predicted through the calculation formula of the arcing time obtained in S3;
s5: and comparing the arcing time predicted by the step S4 with the actual arcing time calculated by the step S2, and judging that the contact of the circuit breaker fails when the deviation of the arcing time and the actual arcing time exceeds a threshold value.
Preferably, the timing marks of the stages of the circuit breaker opening in step S1 include a timing mark for signaling the control terminal at the start of opening, a timing mark for charging the opening coil, a timing mark for the operation of the link, a timing mark for switching the opening auxiliary switch, and a timing mark for the main loop current being zero when the circuit breaker is fully opened.
Preferably, the time scale when the main loop current is zero is directly obtained through a synchrophasor device, and the time scale for switching the opening auxiliary switch is directly obtained through a scheduling automation System (SOE) message.
Preferably, in step S2, the actual arcing time when the circuit breaker is opened is calculated according to the model of the circuit breaker, specifically:
Ttime of arcing=TMain loop current of zero-TAuxiliary switch switching-ΔT
In the formula, TTime of arcingIndicating the actual arcing time, T, when the circuit breaker is openedMain loop current of zeroTime scale, T, indicating zero main loop currentAuxiliary switch switchingAnd the time scale for switching the auxiliary switch is represented, the delta T represents mechanical delay, and the delta T has different values for different types of circuit breakers and has a stable fixed value for the same type of circuit breaker.
Preferably, the step S3 is to obtain n-time historical opening data of the circuit breaker to be evaluated, specifically:
obtaining n times of historical opening data of the circuit breaker to be evaluated, wherein the opening data comprises n times of historical actual arcing time T of the circuit breaker to be evaluated, which is obtained by calculation through the methods in the steps S1 and S2iAnd the corresponding on-off current value I of the control terminal signal timing marki。
Preferably, in step S3, the calculation formula of the arcing time of the circuit breaker to be evaluated is obtained through fitting, and the fitting is linear least square fitting.
Preferably, in step S3, the calculation formula of the arcing time of the circuit breaker to be evaluated is obtained through fitting, specifically:
to (x)i,yi) Performing a linear least squares fit, (x)i,yi)=(Ii,Ti) With y = kx as the objective function, then:
and solving the functional relation between the arcing time and the breaking current according to the formula, wherein different circuit breakers have different coefficients k.
Preferably, in step S5, the predicted arcing time of S5 is compared with the actual arcing time calculated in S2, specifically:
preferably, the threshold of step S5 is 10%.
An online evaluation system for failure of a contact of a circuit breaker, comprising:
the data acquisition module is used for acquiring time marks of each stage when the breaker is opened;
the calculation module is used for calculating the actual arcing time when the breaker is opened according to the model of the breaker;
the fitting module is used for acquiring n-time historical brake opening data of the circuit breaker to be evaluated and solving a calculation formula of arcing time of the circuit breaker to be evaluated through fitting;
the prediction module is used for predicting the arcing time through a calculation formula of the arcing time obtained by the fitting module when the circuit breaker to be evaluated generates a new primary opening operation;
and the judging module is used for comparing the arcing time predicted by the predicting module with the actual arcing time calculated by the calculating module, and judging that the contact of the circuit breaker fails when the deviation of the arcing time predicted by the predicting module and the actual arcing time exceeds a threshold value.
Compared with the prior art, the technical scheme of the invention has the beneficial effects that:
according to the method, no hardware equipment is added, the arcing time is accurately calculated by acquiring the time scale of each state in the opening process of the circuit breaker and the time delay of the circuit breaker with the same model is fixed and stable in each action process, and meanwhile, the arcing time is associated with the actual operation data of the circuit breaker by using a fitting method, so that the final judgment is more accurate.
Drawings
FIG. 1 is a schematic flow chart of the method of the present invention.
Fig. 2 is a schematic time scale diagram of each state when the circuit breaker is opened.
FIG. 3 is a block diagram of the system of the present invention.
Detailed Description
The drawings are for illustrative purposes only and are not to be construed as limiting the patent;
for the purpose of better illustrating the embodiments, certain features of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product;
it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.
The technical solution of the present invention is further described below with reference to the accompanying drawings and examples.
Example 1
The embodiment provides an online evaluation method for contact failure of a circuit breaker, as shown in fig. 1, which includes the following steps:
s1: acquiring time marks of each stage when the breaker is opened;
s2: calculating the actual arcing time of the breaker during opening according to the model of the breaker;
s3: obtaining n-time historical brake opening data of the circuit breaker to be evaluated, and solving a calculation formula of arcing time of the circuit breaker to be evaluated through fitting;
s4: when the circuit breaker to be evaluated has a new primary opening operation, the arcing time is predicted through the calculation formula of the arcing time obtained in S3;
s5: and comparing the arcing time predicted by the step S4 with the actual arcing time calculated by the step S2, and judging that the contact of the circuit breaker fails when the deviation of the arcing time and the actual arcing time exceeds a threshold value.
The time scales of each stage when the circuit breaker is opened in the step S1 include a time scale of control terminal signaling at the start of opening, a time scale of opening coil electrification, a time scale of link action, a time scale of opening auxiliary switch switching, and a time scale of main loop current being zero when the circuit breaker is fully opened.
The time scale of the main loop current being zero is directly obtained through a synchronous phasor device, and the time scale of the switching of the opening auxiliary switch is directly obtained through an SOE message of a dispatching automation system.
In the step S2, the actual arcing time when the circuit breaker is opened is calculated according to the model of the circuit breaker, which specifically includes:
Ttime of arcing=TMain loop current of zero-TAuxiliary switch switching-ΔT
In the formula, TTime of arcingIndicating the actual arcing time, T, when the circuit breaker is openedMain loop current of zeroTime scale, T, indicating zero main loop currentAuxiliary switch switchingAnd the time scale for switching the auxiliary switch is represented, the delta T represents mechanical delay, and the delta T has different values for different types of circuit breakers and has a stable fixed value for the same type of circuit breaker.
Taking a sulfur hexafluoride high-voltage circuit breaker as an example, the switching-off process is as follows: the control terminal sends an opening operation signal, the opening operation signal passes through the auxiliary switch and reaches the opening coil, the opening coil is electrified, the electromagnetic force generated by the current of the opening coil overcomes the resistance of the iron core such as self gravity, motion friction force, spring counter force and the like to drive the iron core to move, the iron core impacts the sincere body in the moving process, the opening keeps the sincere body to release, the opening tripper releases the opening stop pin on the main crank arm, the opening spring releases energy to drive the transmission crank arm, the transmission crank arm drives the main crank arm to rotate through the pull rod, and the breaker body starts to move. The pull rod drives the connecting lever box to move, the connecting lever box moves the movable end (comprising an insulating pull rod, a movable arc contact, a nozzle, a pressure cylinder and a main contact) of the arc extinguish chamber to move, and the piston compresses the gas in the pressure cylinder. When the arc current crosses zero, the spout of the arc extinguish chamber is opened, SF6 gas is sprayed out from the spout and the throat, the pressure is released, the gas flow speed reaches supersonic speed due to the large pressure difference between the upstream and the downstream of the spout, a large amount of heat and charged particles of the arc are taken away, and the arc is extinguished and the disconnection is successful when the thermal recovery speed and the insulation recovery speed of the insulation medium between the fractures are greater than the voltage recovery speed after the arc current crosses zero.
As shown in fig. 2, the opening time includes the opening time and the arcing time, the time difference from the opening start (control terminal signaling) to the full opening (main circuit current is zero) is the full opening time, the time difference from the opening start (control terminal signaling) to the mechanical opening (just opening point) is the opening time, and the time difference from the mechanical opening (just opening point) to the full opening (main circuit current is zero) is the arcing time. However, no time scale of the 'just-separating point' can be obtained, but the time difference from the 'opening auxiliary switch switching' to the 'just-separating point' is fixed for the same type of circuit breaker and stable in each action process, and is recorded as a mechanical delay delta T, so the arcing time can be obtained by subtracting the time scale of the 'auxiliary switch switching' from the time scale of the 'main loop current being zero' and then subtracting the mechanical delay delta T from the time scale of the 'auxiliary switch switching'.
In step S3, acquiring n-time historical opening data of the circuit breaker to be evaluated, specifically:
obtaining n times of historical opening data of the circuit breaker to be evaluated, wherein the opening data comprises n times of historical actual arcing time T of the circuit breaker to be evaluated, which is obtained by calculation through the methods in the steps S1 and S2iAnd the corresponding on-off current value I of the control terminal signal timing marki。
In step S3, a calculation formula of the arcing time of the circuit breaker to be evaluated is obtained by fitting, and the fitting is linear least square fitting.
In step S3, a calculation formula of the arcing time of the circuit breaker to be evaluated is obtained through fitting, specifically:
to (x)i,yi) Performing a linear least squares fit, (x)i,yi)=(Ii,Ti) With y = kx as the objective function, then:
and solving the functional relation between the arcing time and the breaking current according to the formula, wherein different circuit breakers have different coefficients k, and the k is closely related to the actual operation data of the high-voltage circuit breaker.
In step S5, comparing the arcing time predicted in S5 with the actual arcing time calculated in S2, specifically:
the threshold value of step S5 is 10%.
Example 2
The embodiment provides an online evaluation system for contact failure of a circuit breaker, as shown in fig. 3, including:
the data acquisition module is used for acquiring time marks of each stage when the breaker is opened;
the calculation module is used for calculating the actual arcing time when the breaker is opened according to the model of the breaker;
the fitting module is used for acquiring n-time historical brake opening data of the circuit breaker to be evaluated and solving a calculation formula of arcing time of the circuit breaker to be evaluated through fitting;
the prediction module is used for predicting the arcing time through a calculation formula of the arcing time obtained by the fitting module when the circuit breaker to be evaluated generates a new primary opening operation;
and the judging module is used for comparing the arcing time predicted by the predicting module with the actual arcing time calculated by the calculating module, and judging that the contact of the circuit breaker fails when the deviation of the arcing time predicted by the predicting module and the actual arcing time exceeds a threshold value.
The same or similar reference numerals correspond to the same or similar parts;
the terms describing positional relationships in the drawings are for illustrative purposes only and are not to be construed as limiting the patent;
it should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.
Claims (10)
1. The on-line evaluation method for the failure of the contact of the circuit breaker is characterized by comprising the following steps of:
s1: acquiring time marks of each stage when the breaker is opened;
s2: calculating the actual arcing time of the breaker during opening according to the model of the breaker;
s3: obtaining n-time historical brake opening data of the circuit breaker to be evaluated, and solving a calculation formula of arcing time of the circuit breaker to be evaluated through fitting;
s4: when the circuit breaker to be evaluated has a new primary opening operation, the arcing time is predicted through the calculation formula of the arcing time obtained in S3;
s5: and comparing the arcing time predicted by the step S4 with the actual arcing time calculated by the step S2, and judging that the contact of the circuit breaker fails when the deviation of the arcing time and the actual arcing time exceeds a threshold value.
2. The method for online evaluating the contact failure of the circuit breaker according to claim 1, wherein the time scales of each stage of the circuit breaker during opening comprise a time scale of signaling a control terminal at the beginning of opening, a time scale of charging a opening coil, a time scale of a link action, a time scale of switching of an opening auxiliary switch and a time scale of zero main circuit current during full opening in step S1.
3. The on-line evaluation method for contact failure of the circuit breaker according to claim 2, wherein a time scale when the main loop current is zero is directly obtained through a synchrophasor device, and a time scale when the opening auxiliary switch is switched is directly obtained through a scheduling automation System (SOE) message.
4. The on-line evaluation method for the contact failure of the circuit breaker according to claim 2 or 3, wherein the step S2 is to calculate the actual arcing time when the circuit breaker is opened according to the model of the circuit breaker, and specifically comprises the following steps:
Ttime of arcing=TMain loop current of zero-TAuxiliary switch switching-ΔT
In the formula, TTime of arcingIndicating the actual arcing time, T, when the circuit breaker is openedMain loop current of zeroTime scale, T, indicating zero main loop currentAuxiliary switch switchingAnd the time scale for switching the auxiliary switch is represented, the delta T represents mechanical delay, and the delta T has different values for different types of circuit breakers and has a stable fixed value for the same type of circuit breaker.
5. The online evaluation method for contact failure of the circuit breaker according to claim 4, wherein the n-time historical opening data of the circuit breaker to be evaluated is obtained in step S3, and specifically comprises the following steps:
obtaining n times of historical opening data of the circuit breaker to be evaluated, wherein the opening data comprises n times of historical actual arcing time T of the circuit breaker to be evaluated, which is obtained by calculation through the methods in the steps S1 and S2iAnd the corresponding on-off current value I of the control terminal signal timing marki。
6. The method for on-line evaluation of contact failure of circuit breaker according to claim 5, wherein in step S3, the calculation formula of arcing time of the circuit breaker to be evaluated is obtained by fitting, and the fitting is linear least square fitting.
7. The on-line evaluation method for contact failure of the circuit breaker according to claim 6, wherein in step S3, a calculation formula for the arcing time of the circuit breaker to be evaluated is obtained by fitting, and specifically comprises:
to (x)i,yi) Performing a linear least squares fit, (x)i,yi)=(Ii,Ti) To do so byAs an objective function, there are:
and solving the functional relation between the arcing time and the breaking current according to the formula, wherein different circuit breakers have different coefficients k.
9. the online evaluation method for contact failure of the circuit breaker according to claim 8, wherein the threshold value of step S5 is 10%.
10. An online evaluation system for failure of a contact of a circuit breaker, comprising:
the data acquisition module is used for acquiring time marks of each stage when the breaker is opened;
the calculation module is used for calculating the actual arcing time when the breaker is opened according to the model of the breaker;
the fitting module is used for acquiring n-time historical brake opening data of the circuit breaker to be evaluated and solving a calculation formula of arcing time of the circuit breaker to be evaluated through fitting;
the prediction module is used for predicting the arcing time through a calculation formula of the arcing time obtained by the fitting module when the circuit breaker to be evaluated generates a new primary opening operation;
and the judging module is used for comparing the arcing time predicted by the predicting module with the actual arcing time calculated by the calculating module, and judging that the contact of the circuit breaker fails when the deviation of the arcing time predicted by the predicting module and the actual arcing time exceeds a threshold value.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202011013758.0A CN111933460B (en) | 2020-09-24 | 2020-09-24 | Online evaluation method and system for failure of circuit breaker contact |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202011013758.0A CN111933460B (en) | 2020-09-24 | 2020-09-24 | Online evaluation method and system for failure of circuit breaker contact |
Publications (2)
Publication Number | Publication Date |
---|---|
CN111933460A true CN111933460A (en) | 2020-11-13 |
CN111933460B CN111933460B (en) | 2021-03-02 |
Family
ID=73334169
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202011013758.0A Active CN111933460B (en) | 2020-09-24 | 2020-09-24 | Online evaluation method and system for failure of circuit breaker contact |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN111933460B (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN113504465A (en) * | 2021-07-08 | 2021-10-15 | 广东电网有限责任公司 | Method and device for diagnosing faults of high-voltage circuit breaker |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101806861A (en) * | 2010-04-19 | 2010-08-18 | 哈尔滨工业大学 | Method for judging category of failures caused by electrical contact in sealed electromagnetic relay |
US9140757B2 (en) * | 2012-03-27 | 2015-09-22 | Essex Electronics, Inc. | Testing a circuit assembly that contains a piezoelectric switch |
CN107085183A (en) * | 2017-04-27 | 2017-08-22 | 中国南方电网有限责任公司 | A kind of breaker anomalous discrimination method based on wavelet package transforms and normal distribution law |
CN110187263A (en) * | 2019-05-27 | 2019-08-30 | 罗孚电气(中国)有限公司 | Method, apparatus and system based on arcing time assessment contact failure |
-
2020
- 2020-09-24 CN CN202011013758.0A patent/CN111933460B/en active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101806861A (en) * | 2010-04-19 | 2010-08-18 | 哈尔滨工业大学 | Method for judging category of failures caused by electrical contact in sealed electromagnetic relay |
US9140757B2 (en) * | 2012-03-27 | 2015-09-22 | Essex Electronics, Inc. | Testing a circuit assembly that contains a piezoelectric switch |
CN107085183A (en) * | 2017-04-27 | 2017-08-22 | 中国南方电网有限责任公司 | A kind of breaker anomalous discrimination method based on wavelet package transforms and normal distribution law |
CN110187263A (en) * | 2019-05-27 | 2019-08-30 | 罗孚电气(中国)有限公司 | Method, apparatus and system based on arcing time assessment contact failure |
Non-Patent Citations (2)
Title |
---|
储依帆: "铁路信号安全型继电器的可靠性评估方法研究", 《工程科技Ⅱ辑》 * |
魏江: "气氛对触点分断燃弧时间影响的实验与理论研究", 《工程科技Ⅱ辑》 * |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN113504465A (en) * | 2021-07-08 | 2021-10-15 | 广东电网有限责任公司 | Method and device for diagnosing faults of high-voltage circuit breaker |
CN113504465B (en) * | 2021-07-08 | 2023-06-02 | 广东电网有限责任公司 | Method and device for diagnosing faults of high-voltage circuit breaker |
Also Published As
Publication number | Publication date |
---|---|
CN111933460B (en) | 2021-03-02 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN105425145A (en) | Monitoring method for electrical endurance of arc-extinguishing chamber of circuit breaker and determination method for initial time of arcing current | |
CN106531480B (en) | Vacuum circuit breaker contact on-line monitoring method | |
EP2612338B1 (en) | Circuit breaker interrupter travel curve estimation | |
CN201892729U (en) | Electric service life monitoring device of HGIS (hybrid gas insulated switchgear) circuit breaker | |
CN111933460B (en) | Online evaluation method and system for failure of circuit breaker contact | |
CN203732254U (en) | Circuit breaker mechanical characteristic online monitoring device | |
CN106449265B (en) | Vacuum circuit breaker | |
CN108226770A (en) | A kind of circuit breaker failure diagnostic method | |
JP4413270B1 (en) | Switch batch monitoring device, switch batch monitoring method, program | |
CN102646545A (en) | Medium-voltage circuit breaker for online monitoring of mechanical characteristics | |
CN104391245A (en) | Method for detecting mechanical characteristics of circuit breaker | |
US5566041A (en) | Zero-sequence opening of power distribution | |
JP5317724B2 (en) | Switch remote monitoring method, switch remote monitoring system | |
CN115201672A (en) | Method for monitoring mechanical characteristics of switch cabinet on line | |
Andruşcă et al. | About diagnosis of circuit breakers | |
CN113806913B (en) | SF based on arc energy 6 Method for predicting service life of arc extinguishing chamber of circuit breaker | |
CN106768923A (en) | A kind of vacuum arc-extinguishing chamber contact wear extent real-time online intelligent monitoring method and device | |
CN207303018U (en) | A kind of omnipotent breaker | |
CN110849611B (en) | Method for on-line detection of mechanical characteristics of circuit breaker by using switch radiation field | |
CN114329955A (en) | Comprehensive-sensing switch cabinet service life assessment method | |
CN205809249U (en) | A kind of circuit breakers monitoring device | |
Shang et al. | The performance degradation comparison test and failure mechanism of silver metal oxide contact materials | |
CN107863265A (en) | A kind of distribution breaker | |
CN205050781U (en) | Intelligent middling pressure circuit breaker | |
Peng et al. | Test and analysis of mechanical characteristics of circuit breakers |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |