CN101576583A - Method for testing voltage ratio of transformer with phase-shifting winding - Google Patents
Method for testing voltage ratio of transformer with phase-shifting winding Download PDFInfo
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- CN101576583A CN101576583A CNA2009100229819A CN200910022981A CN101576583A CN 101576583 A CN101576583 A CN 101576583A CN A2009100229819 A CNA2009100229819 A CN A2009100229819A CN 200910022981 A CN200910022981 A CN 200910022981A CN 101576583 A CN101576583 A CN 101576583A
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Abstract
The invention discloses a method for testing voltage ratio of a transformer with a phase-shifting winding. The method comprises the following steps: connecting a terminal combination transfer device, which comprises a first transfer switch connected with a high-voltage output single-phase terminal group and a high-voltage input three-phase terminal group as well as a second transfer switch connected with a low-voltage output single-phase terminal group and a low-voltage input three-phase terminal group, between a voltage ratio bridge and a tested transformer; according to the combined connecting positions of corresponding transformer terminals during a test, operating the first transfer switch and the second transfer switch to carry out phase change or combine the high-voltage input three-phase terminal group and the low-voltage input three-phase terminal group, and then operating the voltage ratio bridge to carry out the test; and comparing the data obtained through the test with the theoretical calculation result obtained through a voltage ratio calculation formula with the allowable error meeting national standards. The method can lower manual interference between apparatus and the tested transformer and reduce manual phase alternation and line changing, thereby ensuring the reliability and accuracy of test result.
Description
Technical field
The present invention relates to the test method of transformer voltage ratio, especially to the transformer voltage ratio that has the phase shift winding or the test method of phase shifting angle.
Background technology
Of the same trade both at home and abroad at present various, complicated for transformer voltage ratio that has the phase shift winding and phase shifting angle test method, some method needs special equipment, and technical requirement is very high.Now some voltage ratio electric bridge both domestic and external manufacturers have developed the voltage ratio electric bridge that can comprise that phase shifting angle is measured, but domestic often 10～20 times of external this surveying instrument price, and domestic electric bridge performance is in this respect done is not very stable, and failure rate is very high.Use or the common voltage ratio electric bridge of most of transformer producers.Common voltage ratio electric bridge can't directly carry out voltage ratio and phase shifting angle test to the transformer that has the phase shift winding.And now common voltage ratio electric bridge no matter abroad still domestic manufacturers do not have the conversion of composite design function selecting for testing terminal, thereby by adopting common voltage than electric bridge and rely on and manually testing terminal is made up that realization is carried out voltage ratio to the transformer that has the phase shift winding and the phase shifting angle test seems very difficult.
Summary of the invention
The purpose of this invention is to provide a kind of common voltage that adopts and the transformer that has the phase shift winding is carried out voltage ratio or phase shifting angle test method, can realize simple and reliable operation, increase substantially work efficiency than electric bridge.
For reaching above purpose, the present invention takes following technical scheme to be achieved:
Test method to the transformer voltage ratio that has the phase shift winding comprises the steps:
(1) a terminal combination conversion equipment is connected between voltage ratio electric bridge and the tested transformer, the terminal combination conversion equipment comprises and connects first switch that high pressure is exported single-phase terminal group and high pressure input three-phase terminal group; Connect low pressure and export second switch of single-phase terminal group and low pressure input three-phase terminal group; High pressure is exported high-tension measurement terminal A ', the N ' that single-phase terminal group connects the voltage ratio electric bridge, and low pressure is exported low pressure measurement terminal a ', the n ' that single-phase terminal group connects the voltage ratio electric bridge; High pressure input three-phase terminal group connects HV Terminal A, B, C, the N of tested transformer, and low pressure input three-phase terminal group connects low-voltage terminal a, b, c, the n of tested transformer.
(2) then according to the pairing transformer terminal sub-portfolio wiring position of test, operate first, second switch and carry out commutation or select the three-phase terminal group of high and low pressure input is made up, operating voltage is tested than electric bridge again; Operate first, second switch and carry out commutation or select the three-phase terminal group of high and low pressure input is made up, undertaken by following program:
When 1. first switch was selected A-BC, second switch selected ab, bc, ca to measure respectively, and assembled state is: (A-BC)/and ab, (A-BC)/bc, (A-BC)/ca;
When 2. first switch was selected B-CA, second switch selected ab, bc, ca to measure respectively, and assembled state is: (B-CA)/and ab, (B-CA)/bc, (B-CA)/ca;
When 3. first switch was selected C-AB, second switch selected ab, bc, ca to measure respectively, and assembled state is: (C-AB)/and ab, (C-AB)/bc, (C-AB)/ca;
More than operation totally nine kinds of states can obtain nine groups of data, wherein: power up between mutually at the BC of transformer A and short circuit when A-BC represents to test; When representing to test, B-CA powers up between mutually at the CA of transformer B and short circuit; When representing to test, C-AB powers up between mutually at the AB of transformer C and short circuit; When ab represents to test transformer a and b mutually between induced voltage; When bc represents to test transformer b and c mutually between induced voltage; When ca represents to test transformer c and a mutually between induced voltage.
(3) will test data that obtain and the Theoretical Calculation result that the voltage ratio computing formula obtains and contrast, its franchise gets final product within national standard, and described voltage ratio computing formula is:
K
1＝(A-BC)/ab＝(B-CA)/bc＝(C-AB)/ca
=(K * sin120 °)/sin (60 °-θ)-------formula is 1.
K
2＝(A-BC)/bc＝(B-CA)/ca＝(C-AB)/ab
----------formula 2. for=(K * sin120 °)/sin θ
K
3＝(A-BC)/ca＝(B-CA)/ab＝(C-AB)/bc
=-(K * sin120 °)/sin (60 °+θ)-------formula is 3.
In the formula:
K＝U
AB/U
ab＝U
BC/U
bc＝U
CA/U
ca
U
AB, U
BC, U
CA--------High-Voltage Network side line voltage (kV)
U
Ab, U
Bc, U
Ca--------low pressure valve side line voltage (kV)
θ-----total phase shifting angle θ=(β ± α)
α-----phase shifting angle
Angle between β-----High-Voltage Network side main winding and the low pressure valve side winding.
In the said method, the described computing formula that can obtain phase shifting angle according to resulting voltage ratio K1, K2, K3:
tgθ＝√3×K1/(2×K2+K1)
＝-√3×K3/(2×K2+K3)
-------formula 4. for=-√ 3 (K3+K1)/(K3-K1)
In the formula: θ=n π+arctg (θ) (K2＞0n=0; K2＜0n=1)
Described high pressure is exported single-phase terminal group and is comprised three, and one of them terminal is connected with the terminal N that is connected the transformer high-voltage neutral point and vacantly prepares against usefulness when common transformer tested inner; Low pressure is exported single-phase terminal group and is also comprised three, and one of them terminal is connected with the terminal n that is connected the transformer low voltage neutral point and vacant inner, prepares against usefulness when common transformer tested.
The present invention makes up conversion by the terminal combination conversion equipment to tested transformer test terminal, reduced the manual intervention between instrument and the tested transformer, reduce artificial paraphase thread-changing, the reliability and the accuracy of test findings have been guaranteed, the terminal combination conversion equipment can carry out supporting use with any model voltage ratio electric bridge, thereby has reduced experimentation cost.
Description of drawings
Fig. 1 is the test connection layout of the terminal combination conversion equipment of the inventive method employing.
Among the figure: the tested transformer of 1-; 2-terminal combination conversion equipment; 3-voltage ratio electric bridge DQ; 4-switch (high pressure option); 5-switch (low pressure option); 6-high pressure input three-phase terminal group; 7-low pressure input three-phase terminal group; The 8-high pressure is exported single-phase terminal group; 9-low pressure is exported single-phase terminal group.
Fig. 2 carries out switch constitutional diagram to transformer voltage ratio when test that has the phase shift winding for Fig. 1 terminal combination conversion equipment.
Fig. 3 is the phasor graph of the concrete calculated examples of the present invention.
Fig. 4 carries out switch constitutional diagram to not with the test of the common transformer voltage ratio of phase shift winding the time for Fig. 1 terminal combination conversion equipment.
Embodiment
The present invention is described in further detail below in conjunction with drawings and the specific embodiments.
Symbol description:
A, B, C-----be three terminals of indication transformer high pressure three-phase respectively
A, b, c-----be three terminals of indication transformer low pressure three-phase respectively
N ', n '--connect voltage ratio electric bridge neutral point terminal
N, n----connects the terminal of transformer high-voltage and low pressure neutral point
A ', a '----connect the high and low pressure terminal of voltage ratio electric bridge
When representing to test, A-BC-------powers up between mutually at the BC of transformer A and short circuit
When representing to test, B-CA--------powers up between mutually at the CA of transformer B and short circuit
When representing to test, C-AB--------powers up between mutually at the AB of transformer C and short circuit
As shown in Figure 1, at first a terminal combination conversion equipment 2 is connected between voltage ratio electric bridge 3 and the tested transformer 1, terminal combination conversion equipment 2 comprises and connects first switch 4 that high pressure is exported single-phase terminal group 8 and high pressure input three-phase terminal group 6; Connect low pressure and export second switch 5 of single-phase terminal group 9 and low pressure input three-phase terminal group 7; High pressure is exported high-tension measurement terminal A ', the N ' of two terminals connection voltage ratio electric bridges 3 of single-phase terminal group 8, and a terminal is connected also vacant with the terminal N that is connected the transformer high-voltage neutral point in inside; Low pressure is exported low pressure measurement terminal a ', the n ' of two terminals connection voltage ratio electric bridges 3 of single-phase terminal group 9, and a terminal is connected also vacant with the terminal n that is connected the transformer low voltage neutral point in inside; High pressure input three-phase terminal group 6 connects HV Terminal group A, B, C, the N of tested transformer 1, and low pressure input three-phase terminal group 7 connects low-voltage terminal group a, b, c, the n of tested transformer; According to the pairing transformer terminal sub-portfolio wiring position of test, operation switch 4,5 carries out commutation or selects high and low pressure input three-phase terminal group is made up then, and operating voltage is tested than electric bridge 3 again.
As shown in Figure 2, operate first, second switch and carry out commutation or select the three-phase terminal group of high and low pressure input is made up, carry out according to the following steps:
When first switch was selected A-BC, second switch selected ab, bc, ca to measure respectively, and assembled state is: (A-BC)/and ab, (A-BC)/bc, (A-BC)/ca;
When first switch was selected B-CA, second switch selected ab, bc, ca to measure respectively, and assembled state is: (B-CA)/and ab, (B-CA)/bc, (B-CA)/ca;
When first switch was selected C-AB, second switch selected ab, bc, ca to measure respectively, and assembled state is: (C-AB)/and ab, (C-AB)/bc, (C-AB)/ca;
More than operate totally nine kinds of states (table 1), can obtain K1, K2, nine groups of data of K3.
Table 1
| Terminal combination | A-BC | B-CA | C-AB |
| ab | K1 | K3 | K2 |
| bc | K2 | K1 | K3 |
| ca | K3 | K2 | K1 |
The voltage ratio computing formula is:
K
1＝(A-BC)/ab＝(B-CA)/bc＝(C-AB)/ca
=(K * sin120 °)/sin (60 °-θ)-------formula is 1.
K
2＝(A-BC)/bc＝(B-CA)/ca＝(C-AB)/ab
----------formula 2. for=(K * sin120 °)/sin θ
K
3＝(A-BC)/ca＝(B-CA)/ab＝(C-AB)/bc
=-(K * sin120 °)/sin (60 °+θ)-------formula is 3.
In the formula:
K＝U
AB/U
ab＝U
BC/U
bc＝U
CA/U
ca
U
AB, U
BC, U
CA--------High-Voltage Network side line voltage (kV)
U
Ab, U
Bc, U
Ca---------low pressure valve side line voltage (kV)
θ-----total phase shifting angle θ=(β ± α)
α-----phase shifting angle
Angle between β-----High-Voltage Network side main winding and the low pressure valve side winding.
Thereby can obtain the computing formula of phase shifting angle:
tgθ＝√3×K1/(2×K2+K1)
＝-√3×K3/(2×K2+K3)
-------formula 4. for=-√ 3 (K3+K1)/(K3-K1)
θ＝nπ+arctg(θ) (K2＞0 n＝0；K2＜0 n＝1)
Concrete calculated examples: as a rectifier transformer, phase shifting angle+12 °, 102910 volts of voltage on line side, 731 volts of valve sides.
Phasor graph as shown in Figure 3.Calculated value is as follows:
θ＝(β±α)
β＝30°α＝12°
θ＝30°-12°＝18°
K＝102910/731＝140.779
K
1＝(K×sin120°)/sin(60°-θ)
＝(144.779×sin120°)/sin(60°-18°)
＝182.204
K
2＝(K×sin120°)/sin θ
＝(144.779×sin120°)/sin 18°
＝394.54
K
3＝-(K×sin120°)/sin(60°+θ)
＝(144.779×sin120°)/sin(60°+18°)
＝-124.64
Measured result sees Table 2:
Table 2
| Terminal combination | A-BC | B-CB | C-AB |
| ab | 182.21 | -124.62 | 394.30 |
| bc | 394.70 | 182.26 | -124.64 |
| ca | 124.60 | 394.00 | 182.23 |
Relatively in the The above results, can see that measured value is almost consistent with calculated value.
Less Ki value representation bigger field flux distribution, therefore during by test value counting yield actual voltage ratio, K value, select the Ki value of absolute value minimum for use, select the mean value of two less Ki of absolute value during by the actual phase shifting angle α of test value counting yield for use.
We come the phase shifting angle α and the voltage ratio K of counting yield reality according to the actual result of last planar survey:
We select K for use
1And K
3Mean value.K
1Mean value is 182.233, K
3Mean value is-124.62.
According to formula 4. then: tg θ=-√ 3 (K3+K1)/(K3-K1)=0.3252
So and K2＞0:
θ＝n∏+arctg(θ)＝18.015°
θ=(β ± α) and β=30 °
Then phase shifting angle α=30 are °-18.015 °=11.985 °
° very approaching with α=12 of design.
According to formula 3. then:
Voltage ratio K=UAB/Uab=K
3Sin (60 °+θ)/sin120 °=140.744
＝UBC/Ubc＝K
3sin(60°+θ)/sin120°＝140.766
＝UCA/Uca＝K
3sin(60°+θ)/sin120°＝140.789
The result is consistent with calculated value K=102910/731=140.779.
Present embodiment goes for the transformer voltage ratio of any band phase shift windings such as star connects phase shift, corner connection phase shift, prolongs the limit phase shift, neutral point phase shift and the measurement of phase shifting angle.
For common electric power transformer test, do not relate to problems such as phase shifting angle, test is carried out according to conventional method, and just terminal combination conversion equipment of the present invention provides more combination option, convenient test when can help problematic product analysis.
As shown in Figure 3, receive combination conversion equipment A, B, C terminal or A, B, C, N for common electric power transformer high-voltage three-phase, the low pressure three-phase is received a, b, c terminal or a, b, c, n; At this moment the N ' of voltage ratio electric bridge high-tension measurement terminal group receives on the inner also vacant terminal that is connected with the terminal N that is connected the transformer high-voltage neutral point, voltage ratio electric bridge low pressure measurement terminal group n ' receives on the inner also vacant terminal that is connected with the terminal n that is connected the transformer low voltage neutral point
The operation switch carries out commutation or selects the step that the three-phase terminal group that high and low pressure is imported makes up is comprised:
When first switch was selected A-N, second switch was selected a-n, b-n or c-n;
When first switch was selected B-N, second switch was selected a-n, b-n or c-n;
When first switch was selected C-N, second switch was selected a-n, b-n or c-n;
Common electric power transformer voltage ratio be connected deck label test by fundamental formular:
K＝U
H/U
L
U
H---------high pressure phase voltage (kV)
U
L----------low pressure phase voltage (kV)
Claims (3)
1, a kind ofly it is characterized in that, comprise the steps: having the test method of phase shift winding transformer voltage ratio
(1) a terminal combination conversion equipment is connected between voltage ratio electric bridge and the tested transformer, the terminal combination conversion equipment comprises and connects first switch that high pressure is exported single-phase terminal group and high pressure input three-phase terminal group; Connect low pressure and export second switch of single-phase terminal group and low pressure input three-phase terminal group; High pressure is exported high-tension measurement terminal A ', the N ' that single-phase terminal group connects the voltage ratio electric bridge, and low pressure is exported low pressure measurement terminal a ', the n ' that single-phase terminal group connects the voltage ratio electric bridge; High pressure input three-phase terminal group connects HV Terminal A, B, C, the N of tested transformer, and low pressure input three-phase terminal group connects low-voltage terminal a, b, c, the n of tested transformer;
(2) then according to the pairing transformer terminal sub-portfolio wiring position of test, operate first, second switch and carry out commutation or select the three-phase terminal group of high and low pressure input is made up, operating voltage is tested than electric bridge again; Operate first, second switch and carry out commutation or select the three-phase terminal group of high and low pressure input is made up, undertaken by following program:
When 1. first switch was selected A-BC, second switch selected ab, bc, ca to measure respectively, and assembled state is: (A-BC)/and ab, (A-BC)/bc, (A-BC)/ca;
When 2. first switch was selected B-CA, second switch selected ab, bc, ca to measure respectively, and assembled state is: (B-CA)/and ab, (B-CA)/bc, (B-CA)/ca;
When 3. first switch was selected C-AB, second switch selected ab, bc, ca to measure respectively, and assembled state is: (C-AB)/and ab, (C-AB)/bc, (C-AB)/ca;
More than operation totally nine kinds of states can obtain nine groups of data, wherein: power up between mutually at the BC of transformer A and short circuit when A-BC represents to test; When representing to test, B-CA powers up between mutually at the CA of transformer B and short circuit; When representing to test, C-AB powers up between mutually at the AB of transformer C and short circuit; When ab represents to test transformer a and b mutually between induced voltage; When bc represents to test transformer b and c mutually between induced voltage; When ca represents to test transformer c and a mutually between induced voltage;
(3) will test data that obtain and the Theoretical Calculation result that the voltage ratio computing formula obtains and contrast, its franchise gets final product within national standard, and described voltage ratio computing formula is:
K
1＝(A-BC)/ab＝(B-CA)/bc＝(C-AB)/ca
=(K * sin120 °)/sin (60 °-θ)-------formula is 1.
K
2＝(A-BC)/bc＝(B-CA)/ca＝(C-AB)/ab
----------formula 2. for=(K * sin120 °)/sin θ
K
3＝(A-BC)/ca＝(B-CA)/ab＝(C-AB)/bc
=-(K * sin120 °)/sin (60 °+θ)-------formula is 3.
In the formula:
K＝U
AB/U
ab＝U
BC/U
bc＝U
CA/U
ca
U
AB, U
BC, U
CA---------High-Voltage Network side line voltage (kV)
U
Ab, U
Bc, U
Ca---------low pressure valve side line voltage (kV)
θ-----total phase shifting angle θ=(β ± α)
α-----phase shifting angle
Angle between β-----High-Voltage Network side main winding and the low pressure valve side winding.
2, as claimed in claim 1ly it is characterized in that to having the test method of phase shift winding transformer voltage ratio the computing formula that can obtain phase shifting angle according to resulting voltage ratio K1, K2, K3 is:
tgθ＝√3×K1/(2×K2+K1)
＝-√3×K3/(2×K2+K3)
-------formula 4. for=-√ 3 (K3+K1)/(K3-K1)
In the formula: θ=n π+arctg (θ) K2＞0 n=0; K2＜0 n=1.
3, as claimed in claim 1 to having the test method of phase shift winding transformer voltage ratio, it is characterized in that, described high pressure is exported single-phase terminal group and is comprised three, and one of them terminal is connected with the terminal N that is connected the transformer high-voltage neutral point and vacantly prepares against usefulness when common transformer tested inner; Low pressure is exported single-phase terminal group and is also comprised three, and one of them terminal is connected with the terminal n that is connected the transformer low voltage neutral point and vacant inner, prepares against usefulness when common transformer tested.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009100229819A CN101576583B (en) | 2009-06-18 | 2009-06-18 | Method for testing voltage ratio of transformer with phase-shifting winding |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009100229819A CN101576583B (en) | 2009-06-18 | 2009-06-18 | Method for testing voltage ratio of transformer with phase-shifting winding |
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| Publication Number | Publication Date |
|---|---|
| CN101576583A true CN101576583A (en) | 2009-11-11 |
| CN101576583B CN101576583B (en) | 2010-12-29 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102901872A (en) * | 2012-09-27 | 2013-01-30 | 保定金迪科学仪器有限公司 | Testing method of phase shifting angle of zigzag transformer |
| CN108051662A (en) * | 2017-11-08 | 2018-05-18 | 保定天威集团特变电气有限公司 | More device body series transformer test methods, assembly and test system |
| CN112563055A (en) * | 2020-12-17 | 2021-03-26 | 中车株洲电机有限公司 | Switch cabinet for multi-system transformer |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100592091C (en) * | 2007-11-26 | 2010-02-24 | 天津理工大学 | Transformer regulation measuring systems based on virtual instrument |
-
2009
- 2009-06-18 CN CN2009100229819A patent/CN101576583B/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102901872A (en) * | 2012-09-27 | 2013-01-30 | 保定金迪科学仪器有限公司 | Testing method of phase shifting angle of zigzag transformer |
| CN108051662A (en) * | 2017-11-08 | 2018-05-18 | 保定天威集团特变电气有限公司 | More device body series transformer test methods, assembly and test system |
| CN112563055A (en) * | 2020-12-17 | 2021-03-26 | 中车株洲电机有限公司 | Switch cabinet for multi-system transformer |
| CN112563055B (en) * | 2020-12-17 | 2024-02-09 | 中车株洲电机有限公司 | Switch cabinet for multi-flow transformer |
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| CN101576583B (en) | 2010-12-29 |
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