CN112462207A  Transformer neutral point composite claw gap selection method and device  Google Patents
Transformer neutral point composite claw gap selection method and device Download PDFInfo
 Publication number
 CN112462207A CN112462207A CN202011253691.8A CN202011253691A CN112462207A CN 112462207 A CN112462207 A CN 112462207A CN 202011253691 A CN202011253691 A CN 202011253691A CN 112462207 A CN112462207 A CN 112462207A
 Authority
 CN
 China
 Prior art keywords
 breakdown voltage
 composite
 gap
 power frequency
 probability
 Prior art date
 Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
 Pending
Links
Images
Classifications

 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
 G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
 G01R31/1227—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials
Abstract
The invention discloses a method and a device for selecting a composite claw gap of a neutral point of a transformer, wherein the method comprises the following steps: obtaining the lightning impulse breakdown voltage U with the probability of 0.1%_{i0.1％}(ii) a Obtaining power frequency breakdown voltage U with 99.9% probability_{g99.9％}(ii) a Breakdown voltage U of lightning impulse according to 0.1% probability_{i0.1％}And 99.9% probability of power frequency breakdown voltage U_{g99.9％}Obtaining a relation curve of the lightning impulse breakdown voltage and the composite goat horn gap distance and a relation curve of the power frequency breakdown voltage and the composite goat horn gap distance through power function numerical fitting; and selecting the numerical range of the composite claw gap distance according to the relationship curve of the lightning impulse breakdown voltage and the composite claw gap distance and the relationship curve of the power frequency breakdown voltage and the composite claw gap distance. The gap distance is determined by adopting a Weibull probability distribution method, so that the composite goat horn gap can discharge power frequency overvoltage, and the safety operation of the lightning arrester is ensured.
Description
Technical Field
The invention relates to the technical field of power equipment manufacturing, in particular to a method and a device for selecting a composite claw gap of a neutral point of a transformer.
Background
The neutral point of a part of transformer in the 110kV power grid is grounded in parallel with the arrester through a gap and the arrester or through the gap. The mode of adopting the parallelly connected clearance of arrester is comparatively common. The protection division of the arrester parallel gap is as follows: the power frequency, resonance and operation overvoltage are borne by the gap, the lightning overvoltage is borne by the lightning arrester, and the gap is used for limiting the power frequency overvoltage with overhigh amplitude and overhigh residual voltage which possibly appear on the lightning arrester, so that the danger is avoided. The mode can protect the neutral point of the transformer and also can play a role of mutual protection, and is the mainstream protection mode at present. In order to ensure that the lightning arrester and the composite claw gap are connected in parallel and the neutral point protection mode of the transformer reliably works, the key point is to determine the insulation fit of the lightning arrester and the gap and reduce the dispersion of gap discharge voltage.
According to relevant regulations, when overvoltage protection is carried out on the neutral point insulation of the transformer by using a gap and metal oxide arrester parallel connection protection mode, when lightning surge occurs, the lightning arrester acts for protection, and the gap is protected from action; when the operation or power frequency overvoltage exceeding the insulation level occurs, the discharge protection is carried out by the protection gap, and the lightning arrester does not act, so that the gap and the lightning arrester meet the following matching principle: firstly, the system loses the ground or generates resonance power frequency overvoltage, and the composite claw gap needs to perform overvoltage discharge action, so that the power frequency breakdown voltage of the composite claw gap needs to be smaller than the ground voltage of a single phase of the lost ground, and the maximum distance of the composite claw gap is determined; and secondly, the residual voltage value of the metal zinc oxide arrester is smaller than the lightning breakdown value of the composite claw gap, so that the minimum distance of the composite claw gap is determined. In order to make the gap and the arrester have better insulation fit, the distance of the gap needs to be accurately determined. The best method for matching the lightning impulse insulation is to make a voltsecond characteristic curve, as shown in fig. 1, but the curve is very heavy and complicated to make.
Engineering typically expresses the breakdown characteristic of the gap with a 50% breakdown voltage, i.e. the voltage at which half of the voltage causes breakdown when the voltage is applied multiple times. When the 50% impact breakdown voltage is determined in an experiment, the more and more accurate the number of times of applying, and the methods for applying the voltage for multiple times include a multistage method and a lifting method. These methods, however, have limitations that characterize only 50% of the probability of discharge values.
Disclosure of Invention
The embodiment of the invention aims to provide a method and a device for selecting a composite claw gap of a neutral point of a transformer, wherein a Weibull probability distribution method is adopted to determine a gap distance by designing two voltage values of 0.1% probability lightning breakdown voltage Ui 0.1% and 99.9% probability power frequency breakdown voltage Ug 99.9%, so that the test process is simplified, the gap breakdown voltage can be accurately obtained, the composite claw gap can effectively release power frequency overvoltage, and the safe operation of a lightning arrester is ensured.
In order to solve the above technical problem, a first aspect of the embodiments of the present invention provides a method for selecting a composite claw gap of a neutral point of a transformer, including the following steps:
obtaining the lightning impulse breakdown voltage U with the probability of 0.1%_{i0.1％}；
Obtaining power frequency breakdown voltage U with 99.9% probability_{g99.9％}；
Lightning impulse breakdown voltage U according to the 0.1% probability_{i0.1％}And said 99.9% probability power frequency breakdown voltage U_{g99.9％}Obtaining a relation curve of the lightning impulse breakdown voltage and the composite claw gap distance and a relation curve of the power frequency breakdown voltage and the composite claw gap distance through power function numerical fitting;
and selecting the numerical range of the composite claw gap distance according to the relationship curve of the lightning impulse breakdown voltage and the composite claw gap distance and the relationship curve of the power frequency breakdown voltage and the composite claw gap distance.
Further, the lightning impulse breakdown voltage U with the probability of 0.1% is obtained_{i0.1％}The method comprises the following steps:
acquiring lightning impulse flashover voltage value U of a first preset group number_{i}To obtain the lightning impulse breakdown voltage U with the probability of 0.1 percent_{i0.1％}。
Further, the lightning impulse flashover voltage value U of the first preset group number is obtained_{i}The method comprises the following steps:
selecting a first gap distance value;
applying a first initial voltage to the composite goat horn gap;
judging whether flashover occurs in the gaps of the composite cavel;
if flashover does not occur, increasing the first initial voltage value by a first preset value, and continuously judging whether flashover occurs in the gap of the composite cavel;
if flashover occurs, recording the voltage value of the flashover of the lightning impulse;
and repeating the steps to obtain the lightning impulse flashover voltage values of a first preset group number.
Further, the power frequency breakdown voltage U with the probability of 99.9% is obtained_{g99.9％}The method comprises the following steps:
obtaining a power frequency breakdown voltage value U of a second preset group number_{g}To obtain the power frequency breakdown voltage U with the probability of 99.9 percent_{g99.9％}。
Further, the power frequency breakdown voltage value U of a second preset group number is obtained_{g}The method comprises the following steps:
acquiring a second gap distance value;
continuously boosting the second gap distance value;
judging whether the composite cavel gap is broken down;
if the composite cavel gap is punctured, recording a power frequency breakdown voltage value;
and repeating the steps to obtain the power frequency breakdown voltage value of a second preset group number.
Correspondingly, a second aspect of the embodiments of the present invention provides a device for selecting a composite claw gap of a neutral point of a transformer, including:
a first obtaining module for obtaining a lightning impulse breakdown voltage U with a probability of 0.1%_{i0.1％}；
A second acquisition module for acquiring a power frequency breakdown voltage U with a probability of 99.9%_{g99.9％}；
A curve fitting module for lightning impulse breakdown voltage U according to the 0.1% probability_{i0.1％}And said 99.9% probability power frequency breakdown voltage U_{g99.9％}Obtaining a relation curve of the lightning impulse breakdown voltage and the composite claw gap distance and a relation curve of the power frequency breakdown voltage and the composite claw gap distance through power function numerical fitting;
and the clearance selection module is used for selecting the numerical range of the composite claw clearance distance according to the relation curve of the lightning impulse breakdown voltage and the composite claw clearance distance and the relation curve of the power frequency breakdown voltage and the composite claw clearance distance.
Further, the first obtaining module obtains a first preset number of lightning impulse flashover voltage values U_{i}Obtaining the lightning impulse breakdown voltage U of the probability of 0.1 percent_{i0.1％}。
Further, the first obtaining module comprises:
a first selecting unit for selecting a first gap distance;
a first voltage unit for applying a first initial voltage to the composite cavel gap;
the first judgment unit is used for judging whether flashover occurs in the gap of the composite cavel;
the first voltage adjusting unit is used for increasing the first initial voltage value by a first preset value when flashover does not occur;
a first recording unit for recording the lightning impulse flashover voltage values of the first preset number of groups when flashover occurs.
Further, the second obtaining module obtains a power frequency breakdown voltage value U of a second preset group number_{g}Obtaining the power frequency breakdown voltage U with the probability of 99.9 percent_{g99.9％}。
Further, the second obtaining module includes:
a second selecting unit for obtaining a second gap distance value;
a second voltage adjustment unit for continuously boosting the second gap distance value;
the second judging unit is used for judging whether the composite cavel gap breaks down or not;
and the second recording unit is used for recording the power frequency breakdown voltage value of the second preset group number when the composite cavel gap is broken down.
The technical scheme of the embodiment of the invention has the following beneficial technical effects:
by designing two voltage values of 0.1% probability lightning breakdown voltage Ui 0.1% and 99.9% probability power frequency breakdown voltage Ug 99.9%, the gap distance is determined by adopting a Weibull probability distribution method, the test process is simplified, the gap breakdown voltage can be accurately obtained, the composite claw gap can effectively discharge power frequency overvoltage, and the safety operation of the lightning arrester is guaranteed.
Drawings
FIG. 1 is a prior art voltsecond characteristic of lightning strike isolation;
fig. 2 is a flowchart of a method for selecting a composite claw gap of a neutral point of a transformer according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of a neutral point composite claw of a transformer according to an embodiment of the present invention;
FIG. 4 is a block diagram of a transformer neutral point composite claw gap selecting apparatus according to an embodiment of the present invention;
fig. 5 is a schematic diagram of a first obtaining module according to an embodiment of the present invention;
fig. 6 is a schematic diagram of a second obtaining module according to an embodiment of the present invention.
Reference numerals:
1. the device comprises a first obtaining module 11, a first selecting unit 12, a first voltage unit 13, a first judging unit 14, a first voltage adjusting unit 15, a first recording unit 2, a second obtaining module 21, a second selecting unit 22, a second voltage adjusting unit 23, a second judging unit 24, a second recording unit 3, a curve fitting module 4 and a gap selecting module.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings in conjunction with the following detailed description. It should be understood that the description is intended to be exemplary only, and is not intended to limit the scope of the present invention. Moreover, in the following description, descriptions of wellknown structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.
Fig. 2 is a flowchart of a method for selecting a neutral point composite claw gap of a transformer according to an embodiment of the present invention.
Fig. 3 is a schematic structural diagram of a neutral point composite claw of a transformer according to an embodiment of the present invention.
Referring to fig. 2 and fig. 3, a first aspect of an embodiment of the present invention provides a method for selecting a composite claw gap of a neutral point of a transformer, including the following steps:
s100, acquiring lightning impulse breakdown voltage U with probability of 0.1%_{i0.1％}。
S200, obtaining power frequency breakdown voltage U with the probability of 99.9%_{g99.9％}。
S300, breakdown voltage U of lightning impulse according to 0.1% probability_{i0.1％}And 99.9% probability of power frequency breakdown voltage U_{g99.9％}And obtaining a relation curve of the lightning impulse breakdown voltage and the composite goat horn gap distance and a relation curve of the power frequency breakdown voltage and the composite goat horn gap distance through power function numerical fitting.
The power function numerical fitting refers to finding out a variable relation according to a data fitting relation curve after experimental data are obtained, further determining a gap distance and a breakdown voltage value, and then determining the probability through weibull probability distribution. Alternatively, the power function numerical fitting may be replaced with polynomial fitting and straight line fitting.
And S400, selecting a numerical range of the composite cavel gap distance according to a relation curve of the lightning impulse breakdown voltage and the composite cavel gap distance and a relation curve of the power frequency breakdown voltage and the composite cavel gap distance.
Specifically, the lightning impulse breakdown voltage U with the probability of 0.1% is obtained in the step S100_{i0.1％}The method comprises the following steps:
acquiring lightning impulse flashover voltage value U of a first preset group number_{i}To obtain the lightning impulse breakdown voltage U with the probability of 0.1 percent_{i0.1％}。
Specifically, a first preset group number of lightning impulse flashover voltage values U are obtained_{i}The method comprises the following steps:
s110, selecting a first gap distance value.
And S120, applying a first initial voltage to the composite cavel gap.
And S130, judging whether flashover occurs in the gaps of the composite cavels.
And S140, if flashover does not occur, increasing the first initial voltage value by a first preset value, and continuously judging whether flashover occurs in the gap of the composite cavel.
And S150, recording the flashover voltage value of the lightning impulse if flashover occurs.
And repeating the steps to obtain the lightning impulse flashover voltage values of the first preset group number.
During the lightning overvoltage test, a method of gradually pressurizing is adopted. Setting a first gap distance d, adding a smaller first initial voltage to the composite cavel gap when the test starts, increasing the voltage by 3kV if flashover does not occur until the flashover occurs, recording the lightning impulse flashover voltage Ui at the moment, and repeating the test for 20 times according to the method under the condition of not changing the first gap distance value of the composite cavel to obtain a group of test data.
Specifically, the power frequency breakdown voltage U with the probability of 99.9% is obtained in the step S200_{g99.9％}The method comprises the following steps: obtaining a power frequency breakdown voltage value U of a second preset group number_{g}To obtain the power frequency breakdown voltage U with the probability of 99.9 percent_{g99.9％}。
Specifically, in step S200, the power frequency breakdown voltage value U of the second preset group number is obtained_{g}The method comprises the following steps:
and S200, acquiring a second gap distance value.
And S210, continuously boosting the second gap distance value.
And S220, judging whether the composite cavel gap is broken down.
And S230, if the composite cavel gap breaks down, recording the power frequency breakdown voltage value.
And repeating the steps to obtain the power frequency breakdown voltage value of the second preset group number.
When a power frequency overvoltage test is carried out, a constantspeed pressurization method is mainly adopted. Setting a second gap distance value, adopting a continuous boosting method, boosting by a voltage regulator at the speed of 1.5kV/s until the gap is broken down, and recording the primary power frequency breakdown voltage Uac under the gap. The above procedure was repeated 20 times without changing the second gap distance value, and a set of test data was obtained.
And processing the obtained test data of 20 times of continuous flashover at the same gap distance according to a Weibull probability distribution method to obtain a voltage value of the composite claw gap under any discharge probability.
In a specific embodiment of this embodiment, the clearance distance is determined by selecting a composite claw clearance with a diameter phi of 15mm and an included angle r of 75 degrees. When the lightning impulse test is carried out, the horn clearance distance is selected to be 106mm, 124mm, 130mm, 136mm and 140 mm. When a power frequency breakdown test is carried out, the gap distance of the horn is selected to be 115mm, 120mm, 125mm, 130mm and 135 mm.
Fig. 4 is a block diagram of a transformer neutral point composite claw gap selecting apparatus according to an embodiment of the present invention.
Accordingly, referring to fig. 4, a second aspect of the embodiments of the present invention provides a transformer neutral point composite claw gap selecting apparatus, including: the device comprises a first acquisition module 1, a second acquisition module 2, a curve fitting module 3 and a gap selection module 4. Wherein, the first obtaining module 1 is used for obtaining the lightning impulse breakdown voltage U with 0.1% probability_{i0.1％}(ii) a The second acquisition module 2 is used for acquiring the power frequency breakdown voltage U with the probability of 99.9%_{g99.9％}(ii) a The curve fitting module 3 is used for the lightning impulse breakdown voltage U according to the probability of 0.1 percent_{i0.1％}And 99.9% probability of power frequency breakdown voltage U_{g99.9％}Obtaining a relation curve of the lightning impulse breakdown voltage and the composite goat horn gap distance and a relation curve of the power frequency breakdown voltage and the composite goat horn gap distance through power function numerical fitting; the clearance selecting module 4 is used for selecting the numerical range of the composite claw clearance distance according to the relation curve of the lightning impulse breakdown voltage and the composite claw clearance distance and the relation curve of the power frequency breakdown voltage and the composite claw clearance distance.
Further, the first obtaining module 1 obtains a first preset number of groups of lightning impulse flashover voltage values U_{i}To obtain the lightning impulse breakdown voltage U with the probability of 0.1 percent_{i0.1％}。
Fig. 5 is a schematic diagram of a first obtaining module according to an embodiment of the present invention.
Specifically, referring to fig. 5, the first obtaining module 1 includes: the device comprises a first selecting unit 11, a first voltage unit 12, a first judging unit 13, a first voltage adjusting unit 14 and a first recording unit 15.
The first selecting unit 11 is configured to select a first gap distance; the first voltage unit 12 is used for applying a first initial voltage to the composite cavel gap; the first judging unit 13 is used for judging whether flashover occurs in the gap between the composite cavel; the first voltage adjustment unit 14 is configured to increase the first initial voltage value by a first preset value when a flashover does not occur; the first recording unit 15 is used for recording a first preset number of groups of lightning impulse flashover voltage values when flashover occurs.
Further, the second obtaining module 2 obtains the power frequency breakdown voltage value U of a second preset group number_{g}To obtain the power frequency breakdown voltage U with the probability of 99.9 percent_{g99.9％}。
Fig. 6 is a schematic diagram of a second obtaining module according to an embodiment of the present invention.
Specifically, referring to fig. 6, the second obtaining module 2 includes: a second selecting unit 21, a second voltage adjusting unit 22, a second judging unit 23, and a second recording unit 24.
The second selecting unit 21 is configured to obtain a second gap distance value; the second voltage adjusting unit 22 is configured to continuously boost the second gap distance value; the second judging unit 23 is configured to judge whether the composite cavel gap breaks down; the second recording unit 24 is used for recording the power frequency breakdown voltage value of a second preset group number when the composite cavel gap is broken down.
The embodiment of the invention aims to protect a method and a device for selecting a neutral point composite claw gap of a transformer, wherein the method comprises the following steps: obtaining the lightning impulse breakdown voltage U with the probability of 0.1%_{i0.1％}(ii) a Obtaining power frequency breakdown voltage U with 99.9% probability_{g99.9％}(ii) a Breakdown voltage U of lightning impulse according to 0.1% probability_{i0.1％}And 99.9% probability of power frequency breakdown voltage U_{g99.9％}Obtaining a relation curve of the lightning impulse breakdown voltage and the composite goat horn gap distance and a relation curve of the power frequency breakdown voltage and the composite goat horn gap distance through power function numerical fitting; according to the relation curve of the lightning impulse breakdown voltage and the composite cavel gap distance and the relation of the power frequency breakdown voltage and the composite cavel gap distanceAnd (5) making a curve, and selecting a numerical range of the composite cavel gap distance. The technical scheme has the following effects:
by designing two voltage values of 0.1% probability lightning breakdown voltage Ui 0.1% and 99.9% probability power frequency breakdown voltage Ug 99.9%, the gap distance is determined by adopting a Weibull probability distribution method, the test process is simplified, the gap breakdown voltage can be accurately obtained, the composite claw gap can effectively discharge power frequency overvoltage, and the safety operation of the lightning arrester is guaranteed.
It is to be understood that the abovedescribed embodiments of the present invention are merely illustrative of or explaining the principles of the invention and are not to be construed as limiting the invention. Therefore, any modification, equivalent replacement, improvement and the like made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. Further, it is intended that the appended claims cover all such variations and modifications as fall within the scope and boundaries of the appended claims or the equivalents of such scope and boundaries.
Claims (10)
1. A transformer neutral point composite claw gap selection method is characterized by comprising the following steps:
obtaining the lightning impulse breakdown voltage U with the probability of 0.1%_{i0.1％}；
Obtaining power frequency breakdown voltage U with 99.9% probability_{g99.9％}；
Lightning impulse breakdown voltage U according to the 0.1% probability_{i0.1％}And said 99.9% probability power frequency breakdown voltage U_{g99.9％}Obtaining a relation curve of the lightning impulse breakdown voltage and the composite claw gap distance and a relation curve of the power frequency breakdown voltage and the composite claw gap distance through power function numerical fitting;
and selecting the numerical range of the composite claw gap distance according to the relationship curve of the lightning impulse breakdown voltage and the composite claw gap distance and the relationship curve of the power frequency breakdown voltage and the composite claw gap distance.
2. The method for selecting the composite claw gap of the neutral point of the transformer as claimed in claim 1, wherein the lightning impulse breakdown voltage U with 0.1% probability is obtained_{i0.1％}The method comprises the following steps:
acquiring lightning impulse flashover voltage value U of a first preset group number_{i}To obtain the lightning impulse breakdown voltage U with the probability of 0.1 percent_{i0.1％}。
3. The method for selecting the gap between the neutral points of the transformer according to claim 2, wherein the first predetermined number of sets of lightning impulse flashover voltage values U are obtained_{i}The method comprises the following steps:
selecting a first gap distance value;
applying a first initial voltage to the composite goat horn gap;
judging whether flashover occurs in the gaps of the composite cavel;
if flashover does not occur, increasing the first initial voltage value by a first preset value, and continuously judging whether flashover occurs in the gap of the composite cavel;
if flashover occurs, recording the voltage value of the flashover of the lightning impulse;
and repeating the steps to obtain the lightning impulse flashover voltage values of a first preset group number.
4. The method for selecting the composite claw gap of the neutral point of the transformer according to claim 1, wherein the power frequency breakdown voltage U with the probability of 99.9% is obtained_{g99.9％}The method comprises the following steps:
obtaining a power frequency breakdown voltage value U of a second preset group number_{g}To obtain the power frequency breakdown voltage U with the probability of 99.9 percent_{g99.9％}。
5. The method for selecting the composite claw gap of the neutral point of the transformer according to claim 1, wherein the power frequency breakdown voltage value U of the second preset group number is obtained_{g}The method comprises the following steps:
acquiring a second gap distance value;
continuously boosting the second gap distance value;
judging whether the composite cavel gap is broken down;
if the composite cavel gap is punctured, recording a power frequency breakdown voltage value;
and repeating the steps to obtain the power frequency breakdown voltage value of a second preset group number.
6. A transformer neutral point composite claw gap selection method is characterized by comprising the following steps:
a first obtaining module for obtaining a lightning impulse breakdown voltage U with a probability of 0.1%_{i0.1％}；
A second acquisition module for acquiring a power frequency breakdown voltage U with a probability of 99.9%_{g99.9％}；
A curve fitting module for lightning impulse breakdown voltage U according to the 0.1% probability_{i0.1％}And said 99.9% probability power frequency breakdown voltage U_{g99.9％}Obtaining a relation curve of the lightning impulse breakdown voltage and the composite claw gap distance and a relation curve of the power frequency breakdown voltage and the composite claw gap distance through power function numerical fitting;
and the clearance selection module is used for selecting the numerical range of the composite claw clearance distance according to the relation curve of the lightning impulse breakdown voltage and the composite claw clearance distance and the relation curve of the power frequency breakdown voltage and the composite claw clearance distance.
7. The transformer neutral point composite claw gap selection device according to claim 6,
the first acquisition module acquires a first preset group number of lightning impulse flashover voltage values U_{i}Obtaining the lightning impulse breakdown voltage U of the probability of 0.1 percent_{i0.1％}。
8. The transformer neutral point composite claw gap selection device according to claim 7, wherein the first obtaining module comprises:
a first selecting unit for selecting a first gap distance;
a first voltage unit for applying a first initial voltage to the composite cavel gap;
the first judgment unit is used for judging whether flashover occurs in the gap of the composite cavel;
the first voltage adjusting unit is used for increasing the first initial voltage value by a first preset value when flashover does not occur;
a first recording unit for recording the lightning impulse flashover voltage values of the first preset number of groups when flashover occurs.
9. The transformer neutral point composite claw gap selection device according to claim 6,
the second acquisition module acquires a power frequency breakdown voltage value U of a second preset group number_{g}Obtaining the power frequency breakdown voltage U with the probability of 99.9 percent_{g99.9％}。
10. The transformer neutral point composite claw gap selection device according to claim 9, wherein the second obtaining module comprises:
a second selecting unit for obtaining a second gap distance value;
a second voltage adjustment unit for continuously boosting the second gap distance value;
the second judging unit is used for judging whether the composite cavel gap breaks down or not;
and the second recording unit is used for recording the power frequency breakdown voltage value of the second preset group number when the composite cavel gap is broken down.
Priority Applications (1)
Application Number  Priority Date  Filing Date  Title 

CN202011253691.8A CN112462207A (en)  20201111  20201111  Transformer neutral point composite claw gap selection method and device 
Applications Claiming Priority (1)
Application Number  Priority Date  Filing Date  Title 

CN202011253691.8A CN112462207A (en)  20201111  20201111  Transformer neutral point composite claw gap selection method and device 
Publications (1)
Publication Number  Publication Date 

CN112462207A true CN112462207A (en)  20210309 
Family
ID=74825922
Family Applications (1)
Application Number  Title  Priority Date  Filing Date 

CN202011253691.8A Pending CN112462207A (en)  20201111  20201111  Transformer neutral point composite claw gap selection method and device 
Country Status (1)
Country  Link 

CN (1)  CN112462207A (en) 
Cited By (1)
Publication number  Priority date  Publication date  Assignee  Title 

CN114646285A (en) *  20220311  20220621  哈尔滨理工大学  Method and equipment for determining diameter of ball gap spark switch of transformer neutral point overvoltage suppression system and storage medium 
Citations (7)
Publication number  Priority date  Publication date  Assignee  Title 

CN2779573Y (en) *  20050113  20060510  中国电力科学研究院  Compound transformer neutral point protection gap 
RU2009130030A (en) *  20090805  20110210  Виноградов Андрей Александрович (RU)  METHOD OF PROTECTION AGAINST ELECTRICAL BREAKDOWN OF INSULATION Gaps IN LIQUID DIELECTRIC USING GRID SCREENS WITH CONTROLLED ELECTRICAL CAPACITIES 
CN104635131A (en) *  20150304  20150520  国家电网公司  Method for calculating protective gap distance based on Weibull distribution 
CN104833903A (en) *  20150304  20150812  国家电网公司  Method for determining gap distance of surge arresters containing series gapped structures along with altitude change 
CN105182195A (en) *  20150826  20151223  芜湖市凯鑫避雷器有限责任公司  Gap distance determination method for lightning arrester with series gap 
CN109767886A (en) *  20190327  20190517  长沙理工大学  The antilightning strike broken string of 10kV insulated conductor determines method with protective device and mounting distance 
CN111289862A (en) *  20200330  20200616  山东中安电力科技有限公司  Measurement and protection method and circuit for power frequency withstand voltage test 

2020
 20201111 CN CN202011253691.8A patent/CN112462207A/en active Pending
Patent Citations (7)
Publication number  Priority date  Publication date  Assignee  Title 

CN2779573Y (en) *  20050113  20060510  中国电力科学研究院  Compound transformer neutral point protection gap 
RU2009130030A (en) *  20090805  20110210  Виноградов Андрей Александрович (RU)  METHOD OF PROTECTION AGAINST ELECTRICAL BREAKDOWN OF INSULATION Gaps IN LIQUID DIELECTRIC USING GRID SCREENS WITH CONTROLLED ELECTRICAL CAPACITIES 
CN104635131A (en) *  20150304  20150520  国家电网公司  Method for calculating protective gap distance based on Weibull distribution 
CN104833903A (en) *  20150304  20150812  国家电网公司  Method for determining gap distance of surge arresters containing series gapped structures along with altitude change 
CN105182195A (en) *  20150826  20151223  芜湖市凯鑫避雷器有限责任公司  Gap distance determination method for lightning arrester with series gap 
CN109767886A (en) *  20190327  20190517  长沙理工大学  The antilightning strike broken string of 10kV insulated conductor determines method with protective device and mounting distance 
CN111289862A (en) *  20200330  20200616  山东中安电力科技有限公司  Measurement and protection method and circuit for power frequency withstand voltage test 
NonPatent Citations (1)
Title 

魏书铭: "《农电工必读》", 山东科学技术出版社, pages: 214 * 
Cited By (2)
Publication number  Priority date  Publication date  Assignee  Title 

CN114646285A (en) *  20220311  20220621  哈尔滨理工大学  Method and equipment for determining diameter of ball gap spark switch of transformer neutral point overvoltage suppression system and storage medium 
CN114646285B (en) *  20220311  20221115  哈尔滨理工大学  Method and equipment for determining diameter of ball gap spark switch of transformer neutral point overvoltage suppression system and storage medium 
Similar Documents
Publication  Publication Date  Title 

CN112462207A (en)  Transformer neutral point composite claw gap selection method and device  
US9190829B2 (en)  Surge protector  
CN109245066B (en)  A kind of ultrahightension power transmission line allwave overvoltage protection method  
CN105182195A (en)  Gap distance determination method for lightning arrester with series gap  
CN203397798U (en)  Builtin column type voltage limiter for overhead conductor  
CN108680798B (en)  Lightning monitoring and early warning method and system  
CN103179773B (en)  The automatic high pressure exercise method of highpressure type accelerator and automatic high pressure exercise system  
US20220375704A1 (en)  Pulse voltage conditioning method of vacuum interrupter with automatic conditioning energy adjustment  
CN116365496A (en)  Method for selecting highvoltage singlecore cable sheath protector  
CN113178852B (en)  Insulation matching method, device, equipment and medium for lightning invasion waves of transformer substation  
US6957117B2 (en)  Portable protective air gap tool and method  
CN105098757A (en)  Method for eliminating resonance of power distribution station  
WO2022078527A1 (en)  Transient voltage control method and apparatus for ultrahighvoltage hybrid directcurrent power transmission system  
CN110082652B (en)  Selection method and device for arcing horn and insulator string in overhead transmission line  
CN114784777A (en)  Configuration optimization method and system for highvoltage cable sheath protector  
CN208027838U (en)  A kind of ZincOxide Arrester  
CN106655067A (en)  Line flashover protector  
Pramana et al.  Clamp Design for Distribution Line Covered Conductor  
CN204288986U (en)  A kind of New Zinc Oxide Lightning Arrester  
CN111917109B (en)  Arc extinction and overvoltage protection method for intelligent switch  
CN114646285B (en)  Method and equipment for determining diameter of ball gap spark switch of transformer neutral point overvoltage suppression system and storage medium  
CN111044809B (en)  Test method for measuring maximum protection distance of lightning protection device  
CN113690869B (en)  Transformer substation's line side arrester  
KR102152703B1 (en)  Current Lead for High Voltage Apparatus  
CN110992636B (en)  Electrical fire early warning method 
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 