CN113884949B - Hexagonal graph test vector synthesis method suitable for transformer double-branch power supply - Google Patents
Hexagonal graph test vector synthesis method suitable for transformer double-branch power supply Download PDFInfo
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- CN113884949B CN113884949B CN202111116686.7A CN202111116686A CN113884949B CN 113884949 B CN113884949 B CN 113884949B CN 202111116686 A CN202111116686 A CN 202111116686A CN 113884949 B CN113884949 B CN 113884949B
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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
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/62—Testing of transformers
Abstract
The invention provides a hexagonal diagram test vector synthesis method suitable for transformer double-branch power supply, which relates to the technical field of relay protection vector measurement and comprises the following steps: s1, data acquisition, S2, A phase double-branch current vector synthesis, S3, B phase double-branch current vector synthesis, S4, C phase double-branch current vector synthesis. According to the invention, aiming at the condition that one side of the transformer is double-branch power supply, double-branch current is used as vector sum to calculate sum current vector, and the sum current vector is used as a secondary vector which finally participates in differential flow calculation at the side, so that the accuracy of a result obtained by testing a hexagonal diagram of the transformer is effectively improved.
Description
Technical Field
The invention relates to the technical field of relay protection vector measurement, in particular to a hexagonal diagram test vector synthesis method suitable for transformer double-branch power supply.
Background
The transformer is an important component of a transformer substation, the differential protection is used as the most important protection device for protecting the main transformer, the protection principle is simple, the protection range is clear, and the differential protection is used as the most important component of the main protection for protecting the transformer.
After a new transformer substation, a main transformer technical improvement overhaul or a differential protection CT secondary circuit is changed, the transformer hexagonal diagram test work needs to be carried out with load so as to ensure that the differential protection CT circuit is correct, and avoid false operation and refusal operation of the differential protection in the future and even enlarge accidents. Hexagonal graph test work
For the condition that the low-voltage side of the transformer is a lifting cabinet or the high-voltage side switch is provided with an inner bridge connection line of two switches of a wire inlet switch and a sectional switch, the amplitude and the phase angle of secondary currents of two branches CT are possibly greatly different under the influence of load, so that the difference current error can be greatly calculated by simply combining the magnitude of secondary currents of the two branches CT with the magnitude of the secondary currents of the CT of other side switches CT and vector combination, the current vector sum of the two branches can not be automatically synthesized according to the connection form by the conventional hexagonal graph tester, and the current vector sum of the two branches under the condition of double-branch power supply is used as the basis for testing the hexagonal graph and calculating the difference current.
In summary, developing a hexagonal graph test vector synthesis method suitable for transformer dual-branch power supply is still a critical problem to be solved in the technical field of relay protection vector measurement.
Disclosure of Invention
Aiming at the situation that certain transformers are supplied with double-branch power when a main transformer hexagonal chart is tested, the invention considers the possible phase difference and amplitude difference of two branch secondary currents and considers each possibility of leading and lagging of the two branch currents, the vector sum of the two branch secondary currents is calculated by taking the measured amplitudes of the two branch secondary currents and the phase angles of the two branch secondary currents relative to a reference voltage as data basis, and the hexagonal chart test and the differential flow calculation are the most accurate by using the vector sum method.
In order to achieve the above purpose, the invention is realized by the following technical scheme: a hexagonal diagram test vector synthesis method suitable for transformer double-branch power supply comprises the following steps:
s1, data acquisition;
s2, synthesizing a phase A double-branch current vector;
s3, synthesizing a B-phase double-branch current vector;
s4, synthesizing C-phase double-branch current vectors.
The invention is further provided with: in the S1 operation step, data acquisition includes the following steps:
s101, setting a phase reference of a double-branch power supply side: taking the phase A voltage of the side as a reference, and carrying out angle Ua=0°;
s102, measuring 1 branch A phase current I A1 Angle theta A1 ；
S103, measuring 1 branch B phase current I B1 Angle theta B1 ；
S104, measuring 1 branch C phase current I C1 Angle theta C1 ；
S105, measuring 2-branch A-phase current I A2 Angle theta A2 ；
S106, measuring 2-branch B-phase current I B2 Angle theta B2 ；
S107 measuring 2-branch C-phase current I C2 Angle theta C2 。
The invention is further provided with: in the S2 operation step, the a-phase double-branch current vector synthesis includes the following steps:
s201, calculating amplitude: the voltage of the A phase at the side of the vector is used for measuringFor reference (I)>Is 0 DEG,/v>The current vector measured for branch 1, which is equal to +.>The included angle between them is theta A1 ，/>The current vector measured for branch 2, which is equal to the current of phase A>The included angle between them is theta A2 Two branches A phase current vector +.>And->The included angle between them is theta A1 -θ A2 According to the cosine law, the combined current vector of the two branches +.>The method comprises the following steps: />
S202, calculating an angle: according to the cosine law, the current can be obtainedAngle theta of (2) A ，
The invention is further provided with: in the S3 operation step, the B-phase dual-branch current vector synthesis includes the following steps:
s301, calculating amplitude: the B phase voltage at the side of the vector is used for vector measurementFor reference (I)>Is 0 DEG,/v>The current vector measured for branch 1, which is equal to +.>The included angle between them is theta B1 ，/>The current vector measured for branch 2, which is equal to the local B-phase voltage +.>The included angle between them is theta B2 Two branch B-phase current vectors +.>And->The included angle between them is theta B1 -θ B2 According to the cosine law, the combined current vector of the two branches +.>The method comprises the following steps: />
S302, calculating an angle: according to cosineTheorem that the current can be obtainedAngle theta of (2) B ,
The invention is further provided with: in the S4 operation step, the C-phase double-branch current vector synthesis includes the following steps:
s401, calculating amplitude: the vector is measured by the C-phase voltage of the sideFor reference (I)>Is 0 DEG,/v>The current vector measured for branch 1, which is equal to +.>The included angle between them is theta C1 ，/>The current vector measured for branch 2, which is equal to the local C-phase voltage +.>The included angle between them is theta C2 Two branches C-phase current vector +.>And->The included angle between them is theta C1 -θ C2 According to the cosine law, the combined current vector of the two branches +.>The method comprises the following steps: />
S402, calculating an angle: according to the cosine law, the current can be obtainedAngle of (2)
The invention provides a hexagonal diagram test vector synthesis method suitable for transformer double-branch power supply. The beneficial effects are as follows:
(1) Aiming at the condition that certain transformers are supplied with power in double branches during the testing of the main transformer hexagonal chart, the invention considers the possible phase difference and amplitude difference of two branch secondary currents and considers the possibility of leading and lagging of the two branch currents, calculates the vector sum of the two branch secondary currents by taking the measured amplitudes of the branch one and branch two secondary currents and the phase angles of the measured branch one and branch two secondary currents relative to the reference voltage as data basis, and performs the hexagonal chart testing and differential flow calculation by using the vector sum method.
(2) The input quantity is fixed, the formula algorithm is fixed, and the lead and lag conditions are considered, so that the method is a universal method for calculating the vector sum of the two-branch secondary currents, and compared with the method which only uses the scalar sum of the two-branch secondary currents as the basis for calculating the difference flow and judging the test result of the hexagonal graph, the method is more accurate and precise.
Drawings
FIG. 1 is a flow chart of a hexagonal diagram test vector synthesis method suitable for transformer dual-branch power supply;
fig. 2 is a schematic diagram of two-branch vector synthesis in a hexagonal diagram test vector synthesis method suitable for transformer double-branch power supply.
Detailed Description
The invention will now be described in further detail with reference to the drawings and specific examples, which are not intended to limit the invention thereto.
Examples:
referring to fig. 1-2, a hexagonal diagram test vector synthesis method suitable for power supply of a transformer with double branches includes the following steps:
step one, data acquisition.
Data acquisition, comprising the following steps:
101 Setting a phase reference on the dual-branch power supply side): based on the current phase a voltage, +_ua=0°.
102 Measuring 1 branch a phase current I) A1 Angle theta A1 。
103 Measuring 1 branch B-phase current I) B1 Angle theta B1 。
104 Measuring 1 branch C phase current I) C1 Angle theta C1 。
105 Measuring 2-branch phase a current I) A2 Angle theta A2 。
106 Measuring 2-branch B-phase current I) B2 Angle theta B2 。
107 Measuring 2-branch C-phase current I) C2 Angle theta C2 。
And step two, synthesizing an A-phase double-branch current vector.
The phase A double-branch current vector synthesis comprises the following steps:
201 Magnitude calculation): the voltage of the A phase at the side of the vector is used for measuringFor reference (I)>Is 0 DEG,/v>The current vector measured for branch 1, which is equal to +.>The included angle between them is theta A1 ，/>The current vector measured for branch 2, which is equal to the current of phase A>The included angle between them is theta A2 Two branches A phase current vector +.>And->The included angle between them is theta A1 -θ A2 According to the cosine law, the combined current vector of the two branches +.>The method comprises the following steps: />
202 Angle calculation): according to the cosine law, the current can be obtainedAngle theta of (2) A ，
The above measured values are the amplitude and phase measured as the current secondary vector required in the present invention using a phase meter with the current side a phase voltage as a reference.
And thirdly, synthesizing a B-phase double-branch current vector.
B-phase double-branch current vector synthesis comprises the following steps:
301 Magnitude calculation): vector quantityBy the B-phase voltage of the current side during measurementFor reference (I)>Is 0 DEG,/v>The current vector measured for branch 1, which is equal to +.>The included angle between them is theta B1 ，/>The current vector measured for branch 2, which is equal to the local B-phase voltage +.>The included angle between them is theta B2 Two branch B-phase current vectors +.>And->The included angle between them is theta B1 -θ B2 According to the cosine law, the combined current vector of the two branches +.>The method comprises the following steps: />
302 Angle calculation): according to the cosine law, the current can be obtainedAngle of (2)
And step four, synthesizing a C-phase double-branch current vector.
The C-phase double-branch current vector synthesis comprises the following steps:
401 Magnitude calculation): the vector is measured by the C-phase voltage of the sideFor reference (I)>Is 0 DEG,/v>The current vector measured for branch 1, which is equal to +.>The included angle between them is theta C1 ，/>The current vector measured for branch 2, which is equal to the local C-phase voltage +.>The included angle between them is theta C2 Two branches C-phase current vector +.>And->The included angle between them is theta C1 -θ C2 According to the cosine law, the combined current vector of the two branches +.>The method comprises the following steps: />
402 Angle calculation): according to the cosine law, the current can be obtainedAngle of (2)
The above steps have obtained the vector sum of the two branch secondary currentsThe vector is used as a further hexagonal plot test and the difference stream calculation is more accurate than simply taking the scalar sum of the current magnitudes into account for further calculations.
The present invention considers the phase angle theta between branch one and branch two A1 、θ A2 Who is not predetermined, who is lagging, when θ A1 Greater than theta A2 At the time of theta A Is less than theta A1 In the case of theta A1 Less than theta A2 At the time of theta A Is greater than theta A1 But is provided withInverse function of->Must be positive numbers, in order to ensure that the result is correct and correct, and in order to build a universal mathematical algorithm and mathematical model,is multiplied by a coefficient->The coefficient isNot be1 is-1, when θ A1 Greater than theta A2 When the coefficient is positive, the coefficient is +.>The resulting θ A Is less than theta A1 The result obtained is correct when θ A1 Less than theta A2 Coefficient->Is a negative number of the number,the resulting θ A Is greater than theta A1 The results obtained were also correct.
Aiming at the condition that certain transformers are supplied with power by double branches when a main transformer hexagonal chart is tested, the possible phase difference and amplitude difference of two branch secondary currents are considered, the possibility of leading and lagging of the two branch secondary currents is considered, the measured amplitudes of the branch primary and branch secondary currents and the phase angle of the measured branch primary and branch secondary currents relative to a reference voltage are used as data bases, the vector sum method is used for carrying out hexagonal chart testing and differential flow calculation, the input quantity is fixed, the formula algorithm is fixed, and the condition of leading and lagging is considered, so that the method is a more general method for calculating the vector sum of the two branch secondary currents, and is more accurate and precise compared with the method which only takes the scalar sum of the two branch secondary currents as the bases for calculating the differential flow and judging the hexagonal chart testing result.
The foregoing is merely a preferred embodiment of the present invention, and it should be noted that modifications and improvements could be made by those skilled in the art without departing from the inventive concept, which fall within the scope of the present invention.
Claims (1)
1. The hexagonal diagram test vector synthesis method suitable for transformer double-branch power supply is characterized by comprising the following steps:
s1, data acquisition;
the method comprises the following steps:
s101, setting a phase reference of a double-branch power supply side: taking the phase A voltage of the side as a reference, and carrying out angle Ua=0°;
s102, measuring 1 branch A phase current I A1 Angle theta A1 ；
S103, measuring 1 branch B phase current I B1 Angle theta B1 ；
S104, measuring 1 branch C phase current I C1 Angle theta C1 ；
S105, measuring 2-branch A-phase current I A2 Angle theta A2 ；
S106, measuring 2-branch B-phase current I B2 Angle theta B2 ；
S107 measuring 2-branch C-phase current I C2 Angle theta C2 ；
S2, synthesizing a phase A double-branch current vector;
the method comprises the following steps:
s201, calculating amplitude: the voltage of the A phase at the side of the vector is used for measuringFor reference (I)>Is 0 DEG,/v>The current vector measured for branch 1, which is equal to +.>The included angle between them is theta A1 ，/>The current vector measured for branch 2, which is equal to the current-side phase A voltageThe included angle between them is theta A2 Two branches A phase current vector +.>And->The included angle between them is theta A1 -θ A2 According to the cosine law, the combined current vector of the two branches +.>The method comprises the following steps: />
S202, calculating an angle: according to the cosine law, the current can be obtainedAngle theta of (2) A ，
S3, synthesizing a B-phase double-branch current vector;
the method comprises the following steps:
s301, calculating amplitude: the B phase voltage at the side of the vector is used for vector measurementFor reference (I)>Is 0 DEG,/v>The current vector measured for branch 1, which is equal to +.>The included angle between them is theta B1 ，/>The current vector measured for branch 2, which is equal to the current-side phase B voltageThe included angle between them is theta B2 Two branch B-phase current vectors +.>And->The included angle between them is theta B1 -θ B2 According to the cosine law, the combined current vector of the two branches +.>The method comprises the following steps: />
S302, calculating an angle: according to the cosine law, the current can be obtainedAngle of (2)
S4, synthesizing a C-phase double-branch current vector;
the method comprises the following steps:
s401, calculating amplitude: the vector is measured by the C-phase voltage of the sideFor reference (I)>Is 0 DEG,/v>The current vector measured for branch 1, which is equal to +.>The included angle between them is theta C1 ，/>The current vector measured for branch 2, which is equal to the local C-phase voltageThe included angle between them is theta C2 Two branches C-phase current vector +.>And->The included angle between them is theta C1 -θ C2 According to the cosine law, the combined current vector of the two branches +.>The method comprises the following steps: />
S402, calculating an angle: according to the cosine law, the current can be obtainedAngle theta of (2) C ,
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102124649A (en) * | 2008-08-18 | 2011-07-13 | 日本电信电话株式会社 | Vector synthesis type phase shifter, optical transceiver, and control circuit correction |
| CN208752129U (en) * | 2018-08-17 | 2019-04-16 | 武汉绿能德精测科技有限公司 | A kind of three phase electrical parameters measuring device |
| CN111555289A (en) * | 2020-05-12 | 2020-08-18 | 国网山西省电力公司吕梁供电公司 | Phase compensation based online restraining method for closed-loop circulation of power distribution network |
| CN111999684A (en) * | 2020-08-27 | 2020-11-27 | 国网山东省电力公司淄博供电公司 | One-key type transformer hexagonal diagram rapid tester |
-
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- 2021-09-23 CN CN202111116686.7A patent/CN113884949B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102124649A (en) * | 2008-08-18 | 2011-07-13 | 日本电信电话株式会社 | Vector synthesis type phase shifter, optical transceiver, and control circuit correction |
| CN208752129U (en) * | 2018-08-17 | 2019-04-16 | 武汉绿能德精测科技有限公司 | A kind of three phase electrical parameters measuring device |
| CN111555289A (en) * | 2020-05-12 | 2020-08-18 | 国网山西省电力公司吕梁供电公司 | Phase compensation based online restraining method for closed-loop circulation of power distribution network |
| CN111999684A (en) * | 2020-08-27 | 2020-11-27 | 国网山东省电力公司淄博供电公司 | One-key type transformer hexagonal diagram rapid tester |
Non-Patent Citations (4)
| Title |
|---|
| 18脉波自耦型无源功率因数校正技术;陈根余 等;通信电源技术;第32卷(第05期);第183-185、263页 * |
| 一种18脉冲隔离型变压整流器;张鹏真 等;南京航空航天大学学报;第46卷(第01期);第129-136页 * |
| 串联H桥多电平高压变频器故障处理新方法;杨旭宏 等;变频器世界(第12期);第83-86页 * |
| 基于幅度测量的任意宽带信号相位测量方法;万发雨 等;电测与仪表;第57卷(第03期);第116-121页 * |
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