CN107917661B - Function inspection device for frequency response type winding deformation tester - Google Patents
Function inspection device for frequency response type winding deformation tester Download PDFInfo
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- CN107917661B CN107917661B CN201711175927.9A CN201711175927A CN107917661B CN 107917661 B CN107917661 B CN 107917661B CN 201711175927 A CN201711175927 A CN 201711175927A CN 107917661 B CN107917661 B CN 107917661B
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- 238000004804 winding Methods 0.000 title claims abstract description 48
- 230000004044 response Effects 0.000 title claims abstract description 31
- 238000007689 inspection Methods 0.000 title claims description 7
- 238000000034 method Methods 0.000 claims abstract description 15
- 230000008569 process Effects 0.000 claims abstract description 6
- 239000003990 capacitor Substances 0.000 claims description 47
- 238000004088 simulation Methods 0.000 claims description 25
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 6
- 238000012546 transfer Methods 0.000 claims description 6
- 229910052742 iron Inorganic materials 0.000 claims description 3
- 239000002184 metal Substances 0.000 claims description 3
- 229910052751 metal Inorganic materials 0.000 claims description 3
- 238000012360 testing method Methods 0.000 abstract description 18
- 238000005259 measurement Methods 0.000 abstract description 5
- 230000007547 defect Effects 0.000 abstract description 2
- 238000001514 detection method Methods 0.000 description 8
- 230000009286 beneficial effect Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 5
- 230000008859 change Effects 0.000 description 4
- 238000003745 diagnosis Methods 0.000 description 4
- 230000005284 excitation Effects 0.000 description 3
- 238000012795 verification Methods 0.000 description 3
- 238000012937 correction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000012549 training Methods 0.000 description 1
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/16—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring the deformation in a solid, e.g. by resistance strain gauge
Abstract
The invention discloses a function checking device for a frequency response type winding deformation tester, which relates to the technical field of electric power measurement, and aims at solving the problem that the function checking means of the instrument is lacking when the winding deformation tester is used by a plurality of frequency response methods, and the judging of a test result cannot be influenced by the defect reason of the instrument in the use process; the invention can accurately simulate the distribution parameters of the transformer winding, has simple structure, is easy to realize, and can be tested by simply wiring.
Description
Technical Field
The invention relates to the technical field of electric power measurement, in particular to a function checking device for a frequency response type winding deformation tester.
Background
The transformer is very important primary equipment of a power grid, the transformer winding is a main part of the transformer accident damage, and potential operation risks can be brought due to the fact that the transformer winding is deformed to different degrees in operation due to short circuit impact, insufficient self short circuit resistance and the like. The frequency response method is one of the most common methods for diagnosing the deformation of the transformer winding, and the frequency response type winding deformation tester on the market has various varieties, and has the same problems when in use although the functions of the method are different from each other: because the frequency response method has higher sensitivity and judgment accuracy, the damage of the parts of the instrument and the impedance change of the test loop can influence the test curve, thereby influencing the diagnosis conclusion of the winding deformation, and therefore, before the frequency response method tester is adopted, the influence caused by the change of the detection condition (the instrument) and the detection mode is necessary to be eliminated in order to reflect the real condition of the transformer winding. Currently, the power department generally lacks a special functional verification means for various used winding deformation testers by a frequency response method, and cannot confirm the integrity of the tester before and after use and cannot eliminate the possibility of influence of faults of the tester on a diagnosis result, so that the efficiency of test work and the reliability of the diagnosis result are greatly reduced. The winding deformation tester is sent to a check and correction device to solve the problem of checking the long-term use of the device, and the problem of functional verification cannot be solved in the short-term frequent use process.
Disclosure of Invention
The invention provides a function checking device for a frequency response type winding deformation tester, which is used for solving the problem that the current power department generally lacks a means for checking the functionality of an instrument when using a winding deformation tester with a plurality of frequency response methods, and cannot eliminate the defect cause of the instrument in the using process to influence the judgment of a test result.
In order to solve the problems, the invention adopts the following technical scheme:
a function checking device for a frequency response type winding deformation tester at least comprises an analog unit;
the simulation unit comprises a first branch, a second branch and a grounded capacitance branch, wherein the head end of the first branch is connected with the head end of the second branch and is used as the input end of the simulation unit, the tail end of the first branch is connected with the tail end of the second branch and is used as the output end of the simulation unit, and the head ends of the first branch and the second branch are connected with a ground wire through the grounded capacitance branch;
the first branch comprises an adjustable capacitance module and a first branch switch, and the adjustable capacitance module is connected in series with the first branch switch and is used for simulating the axial distribution capacitance of the winding;
the second branch comprises an adjustable inductance module and a second branch switch, and the adjustable inductance module and the second branch switch are connected in series and are used for simulating the inductance between turns or cakes of the winding;
the adjustable capacitance module comprises a plurality of capacitors and a capacitance change-over switch, wherein the head ends of the capacitors are connected with each other, and the tail ends of the capacitors are respectively connected with different contact points of the capacitance change-over switch;
the adjustable inductance module comprises a plurality of inductors and an inductance transfer switch, wherein the head ends of the inductors are connected with each other, and the tail ends of the inductors are respectively connected with different contact points of the inductance transfer switch;
the grounding capacitor branch circuit comprises a plurality of grounding capacitors and a grounding capacitor change-over switch, wherein the head ends of the grounding capacitors are connected with each other, and the tail ends of the grounding capacitors are respectively connected with different contact points of the grounding capacitor change-over switch. After the preferable technical scheme is adopted, the beneficial effects include: the adjustable module is formed by the change-over switch and the capacitor bank or the inductor bank, so that the circuit connection control and maintenance are convenient.
After the technical scheme is adopted, the beneficial effects include: the scheme can accurately simulate the distribution parameters of the transformer winding, provides accurate verification reference for the frequency response type winding deformation tester, is simple in structure and easy to realize, and can be tested only by simple wiring.
Preferably, the device comprises 3 analog units and 4 connecting terminals, wherein the input end of the first analog unit is connected with the terminal a, the output end of the first analog unit is connected with the input end of the second analog unit, the output end of the second analog unit is connected with the input end of the third analog unit, the output end of the third analog unit is connected with the terminal c, and the terminal b and the terminal c are respectively arranged at two ends of the ground wire. After the preferable technical scheme is adopted, the beneficial effects include: after 3 simulation units are adopted, the accuracy of the whole device for simulating the parameters of the transformer winding is increased, the simulation range is increased, and various types of frequency response winding deformation testers can be conveniently checked.
Preferably, the plurality of capacitors have a capacitance of 1pF, 10pF, 1nF, 10nF, respectively, of a precision monolithic capacitor;
the inductors are patch inductors of 0.1mH, 1mH, 10mH and 47mH respectively;
the plurality of grounded capacitors are precision monolithic capacitors having capacities of 1pF, 10pF, 1nF, 10nF, respectively. After the preferable technical scheme is adopted, the beneficial effects include: the capacitors or inductors with the capacity can be mutually combined into common winding simulation parameters, and are convenient to adjust and replace.
Preferably, the device further comprises a box body, a circuit board, connecting wires and a panel, wherein the circuit board and the connecting wires are arranged in the box body, the panel is arranged on the box body, and capacity values of a capacitor and an inductor are printed on the panel;
the simulation unit is arranged on the circuit board, the side face of the box body is provided with a wiring terminal, and the circuit board is connected with the wiring terminal through a connecting wire. After the preferable technical scheme is adopted, the beneficial effects include: the simulation units are uniformly arranged in the box body, so that the box body is convenient to carry and maintain, and the circuit board and the panel are additionally arranged, so that wiring and operation are convenient.
Preferably, the case has an electromagnetic shielding function. After the preferable technical scheme is adopted, the beneficial effects include: the anti-interference capability of the device is improved, and the measurement accuracy is provided.
Preferably, the box body is made of an iron plate through a sheet metal process. After the preferable technical scheme is adopted, the beneficial effects include: the production cost is reduced, and the mechanical strength of the device is improved.
Drawings
FIG. 1 is a schematic view of a box and a panel structure according to an embodiment of the present invention;
FIG. 2 is a schematic circuit diagram of a simulation unit in accordance with an embodiment of the present invention;
FIG. 3 is a block diagram of the overall circuit of the embodiment provided by the invention;
FIG. 4 is a circuit diagram of a tunable capacitance module and a grounded tunable capacitance module according to an embodiment of the present invention;
fig. 5 is a circuit diagram of an adjustable inductance module in an embodiment provided by the invention.
Description of the embodiments
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to fig. 1 to 5 in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. The detailed description of the embodiments of the invention, generally described and illustrated in the figures herein, is not intended to limit the scope of the invention as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The utility model provides a function inspection device for frequency response formula winding deformation tester, it is the function inspection device that designs to transformer winding and frequency response method characteristic, be used for checking the test function validity of frequency response formula winding deformation tester, in order to improve the credibility of transformer winding deformation diagnosis work, this device includes 3 analog units and 4 binding post, analog unit is as shown in figure 2, including first branch road, second branch road and ground capacitor branch road, first branch road head end is connected and is regarded as the input of this analog unit with second branch road head end, first branch road tail end and second branch road tail end are connected and are regarded as the output of this analog unit, first branch road head end and second branch road head end are connected with the ground wire through ground capacitor branch road;
the first branch comprises an adjustable capacitance module K1 and a first branch switch SK1, and the adjustable capacitance module K1 and the first branch switch SK1 are connected in series and are used for simulating the axial distributed capacitance of the transformer winding;
as shown in fig. 4, the adjustable capacitance module K1 includes precise monolithic capacitors of 1pF, 10pF, 1nF, and 10nF and a capacitance change-over switch, wherein the head ends of the capacitors are connected to each other, and the tail ends are connected to different contact points of the capacitance change-over switch;
the grounding capacitor branch is similar to the adjustable capacitor module and comprises 1pF, 10pF, 1nF, 10nF capacitors and a grounding capacitor change-over switch, wherein the head ends of the grounding capacitors are connected with each other, and the tail ends of the grounding capacitors are connected with different contact points of the grounding capacitor change-over switch respectively.
The second branch comprises an adjustable inductance module L1 and a second branch switch SL1, and the adjustable inductance module L1 and the second branch switch SL1 are connected in series and are used for simulating the inductance between turns or cakes of the winding;
as shown in fig. 5, the adjustable inductance module L1 includes patch inductances of 0.1mH, 1mH, 10mH, and 47mH and an inductance transfer switch, where the head ends of the inductances are connected to each other, and the tail ends of the inductances are connected to different contact points of the inductance transfer switch.
The device comprises 3 analog units and 4 connecting terminals, wherein fig. 3 is a circuit overall structure diagram of the embodiment provided by the invention, as shown in fig. 3, the input end of a first analog unit is connected with a terminal a, the output end of the first analog unit is connected with the input end of a second analog unit, the output end of the second analog unit is connected with the input end of a third analog unit, the output end of the third analog unit is connected with a terminal c, and the terminal b and the terminal c are respectively arranged at two ends of a ground wire; in order to improve the simulation range of the device and facilitate carrying and anti-interference, as shown in fig. 1, the device also comprises a box body, a circuit board, connecting wires and a panel, wherein the box body of the box body is made of iron plates through a sheet metal process, the circuit board and the connecting wires are arranged in the box body, the panel is arranged on the box body, and capacity values of a capacitor and an inductor are printed on the panel; the simulation unit is arranged on the circuit board, the side face of the box body is provided with a wiring terminal, and the circuit board is connected with the wiring terminal through a connecting wire.
Case 1: instrument network access acceptance check
Taking OMICRON FRAnalyzer winding deformation tester as an example, when the tester is first used in network access acceptance, the excitation end of the tester is connected to the a end of the device, the reference signal detection end is connected to the a end of the device, the response signal detection end is connected to the c end of the device, and the grounding shielding ends are connected with the b and d ends and are grounded together with the grounding point of the winding deformation tester. As shown in fig. 1, the adjustable capacitors K1, K2, K3 of the device are all 10pF, the adjustable inductors L1, L2, L3 are all 1mH, and the adjustable capacitors C1, C2, C3 of the device are all 10pF. And then electrifying to start measurement, taking the measured frequency response curve as an initial frequency response curve 1, removing wiring and rewiring after the first test is finished, carrying out the 2 nd test and obtaining an initial frequency response curve 2, comparing the correlation coefficients of the two curves, if the correlation coefficient is more than or equal to 6 (which can be set by referring to the technical specification requirement of an instrument), considering that the network access instrument has good repeatability, recording the capacitance and inductance parameters of the panel at the moment, and taking the second curve as the initial frequency response curve of the instrument, so that the instrument can be conveniently used as a reference when being used later.
Case 2: functional inspection before transformer winding test
Taking OMICRON FRAnalyzer winding deformation tester as an example, before the transformer winding deformation test, the excitation end of the tester is connected to the a end of the device, the reference signal detection end is connected to the a end of the device, the response signal detection end is connected to the c end of the device, and the grounding shielding ends are connected with the b and d ends and are grounded together with the grounding point of the winding deformation tester. As shown in fig. 1, the adjustable capacitors K1, K2, K3 of the device are all 10pF, the adjustable inductors L1, L2, L3 are all 1mH, and the adjustable capacitors C1, C2, C3 of the device are all 10pF. Then electrifying to start measurement, taking the measured frequency response curve as an on-site frequency response curve, comparing correlation coefficients between the on-site frequency response curve and an initial frequency response curve under the parameter state of the device, and if the correlation coefficient is more than or equal to 4 (which can be set according to the use requirement), considering that the state of the instrument is good before the use, and then carrying out winding deformation test to obtain a result with high reliability; if the result is less than 4, searching and removing the reasons outside the instrument, and carrying out functional inspection test again, if the repeated test result still does not meet the requirement, considering that the result obtained by adopting the winding deformation tester at this time has low reliability, and suggesting to carry out winding deformation test after removing the instrument fault reasons.
Case 3: transformer winding deformation simulation test and research training
Take OMICRON FRAnalyzer winding deformation tester as an example, the device can be used as a device for simulating a transformer winding. During simulation test, the excitation end of the tester is connected to the a end of the device, the reference signal detection end is connected to the a end of the device, the response signal detection end is connected to the c end of the device, and the grounding shielding ends are connected with the b and the d and commonly grounded with the grounding point of the winding deformation tester. Setting adjustable capacitors K1, K2 and K3 of the device as any initial value, setting adjustable inductors L1, L2 and L3 as any initial value, setting adjustable capacitors C1, C2 and C3 of the device as any initial value, and electrifying to perform simulation test to obtain an initial curve; and then adjusting K1, K2, K3, L1, L2, L3, C1, C2 and C3 in a variable control mode to simulate the change condition of equivalent parameters when different types of deformation of the transformer winding occur, then performing an adjusted simulated winding deformation test, comparing with an initial curve, and analyzing the influence of different change types on the high frequency band, the medium frequency band and the low frequency band of the frequency response curve.
Claims (6)
1. A functional inspection device for a frequency response type winding deformation tester, characterized in that: at least comprises an analog unit;
the simulation unit comprises a first branch, a second branch and a grounded capacitance branch, wherein the head end of the first branch is connected with the head end of the second branch and is used as the input end of the simulation unit, the tail end of the first branch is connected with the tail end of the second branch and is used as the output end of the simulation unit, and the head ends of the first branch and the second branch are connected with a ground wire through the grounded capacitance branch;
the first branch comprises an adjustable capacitance module and a first branch switch, and the adjustable capacitance module is connected in series with the first branch switch and is used for simulating the axial distribution capacitance of the winding;
the second branch comprises an adjustable inductance module and a second branch switch, and the adjustable inductance module and the second branch switch are connected in series and are used for simulating the inductance between turns or cakes of the winding;
the adjustable capacitance module comprises a plurality of capacitors and a capacitance change-over switch, wherein the head ends of the capacitors are connected with each other, and the tail ends of the capacitors are respectively connected with different contact points of the capacitance change-over switch;
the adjustable inductance module comprises a plurality of inductors and an inductance transfer switch, wherein the head ends of the inductors are connected with each other, and the tail ends of the inductors are respectively connected with different contact points of the inductance transfer switch;
the grounding capacitor branch circuit comprises a plurality of grounding capacitors and a grounding capacitor change-over switch, wherein the head ends of the grounding capacitors are connected with each other, and the tail ends of the grounding capacitors are respectively connected with different contact points of the grounding capacitor change-over switch.
2. The apparatus according to claim 1, wherein:
the device comprises 3 simulation units and 4 wiring terminals, wherein the input end of the first simulation unit is connected with the terminal a, the output end of the first simulation unit is connected with the input end of the second simulation unit, the output end of the second simulation unit is connected with the input end of the third simulation unit, the output end of the third simulation unit is connected with the terminal c, and the terminal b and the terminal c are respectively arranged at two ends of a ground wire.
3. The apparatus according to claim 1, wherein:
the capacitors have the capacities of 1pF, 10pF, 1nF and 10nF respectively;
the inductors are patch inductors of 0.1mH, 1mH, 10mH and 47mH respectively;
the plurality of grounded capacitors are precision monolithic capacitors having capacities of 1pF, 10pF, 1nF, 10nF, respectively.
4. The apparatus according to claim 1, wherein:
the circuit board and the connecting wire are arranged in the box body, the panel is arranged on the box body, and capacity values of the capacitor and the inductor are printed on the panel;
the simulation unit is arranged on the circuit board, the side face of the box body is provided with a wiring terminal, and the circuit board is connected with the wiring terminal through a connecting wire.
5. The apparatus according to claim 4, wherein:
the box body has an electromagnetic shielding function.
6. The apparatus according to claim 5, wherein:
the box body is made of iron plates through a sheet metal process.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711175927.9A CN107917661B (en) | 2017-11-22 | 2017-11-22 | Function inspection device for frequency response type winding deformation tester |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711175927.9A CN107917661B (en) | 2017-11-22 | 2017-11-22 | Function inspection device for frequency response type winding deformation tester |
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| Publication Number | Publication Date |
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| CN107917661A CN107917661A (en) | 2018-04-17 |
| CN107917661B true CN107917661B (en) | 2023-10-27 |
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