CN110907819A - Device and method for testing operating characteristics of on-load tap changer of triangular wiring transformer - Google Patents
Device and method for testing operating characteristics of on-load tap changer of triangular wiring transformer Download PDFInfo
- Publication number
- CN110907819A CN110907819A CN201911388150.3A CN201911388150A CN110907819A CN 110907819 A CN110907819 A CN 110907819A CN 201911388150 A CN201911388150 A CN 201911388150A CN 110907819 A CN110907819 A CN 110907819A
- Authority
- CN
- China
- Prior art keywords
- transformer
- voltage
- changer
- phase
- load tap
- 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
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
- G01R31/3271—Testing of circuit interrupters, switches or circuit-breakers of high voltage or medium voltage devices
Abstract
The invention discloses a device and a method for testing the operating characteristics of an on-load tap changer of a triangular wiring transformer, wherein the device comprises the following components: the device comprises a power generation module, a voltage divider module, a measurement protection module, a data acquisition module and a central processing unit. The invention makes up the technical blank that the action characteristic of the tap changer of the triangular wiring transformer can not be tested by a direct current method in the prior art, can protect a testing device, has the advantages of simple design, strong practicability, high testing precision and the like, and meets the production requirement.
Description
Technical Field
The invention belongs to the technical field of power testing, and particularly relates to a device and a method for testing the operating characteristics of an on-load tap-changer of a triangular wiring transformer.
Background
An on-load tap changer (OLTC) is an important component of a power transformer, and its operation conditions are directly related to the stability and safety of the transformer and the system. The OLTC is the only moving part of the transformer and belongs to one of the parts with the highest fault rate of the transformer, so that the performance of the OLTC is periodically checked, and the OLTC has great significance for the safe operation of the transformer and a power system. DL/T265 "transformer on-load tap changer field test guideline" stipulates that the conversion procedure, current continuity and out-of-sync time with three-phase switching on and off of a tap changer need to be measured periodically.
At present, a direct current method is mostly adopted for testing an on-load tap-changer of a transformer in the field of the power industry, a phase current of a certain phase winding of the transformer is measured by pressurizing the phase winding, and the performance state of the tap-changer is judged by comparing an obtained phase current waveform with a routine test waveform of a tap-changer manufacturer. However, this method is only suitable for star-connected large transformers, and for delta-connected transformers, it is impossible to test the transformers because the phase currents cannot be obtained.
In recent years, as the degree of intellectualization in a transformer substation is higher and higher, a large amount of equipment such as an air conditioner is put into use, a fire extinguishing system is transformed from a nitrogen-filled fire extinguishing system to a water spraying system, so that the load in the transformer substation has large fluctuation, and in order to prevent the large voltage fluctuation of a 400V power system in the transformer substation, the transformer for the on-load voltage regulation station has become the mainstream trend. Most transformer for stations adopts a triangular connection mode, so that the traditional direct current test method cannot test.
Disclosure of Invention
The invention aims to provide a device and a method for testing the action characteristics of an on-load tap changer of a triangular wiring transformer, so as to make up for the technical blank that the action characteristics of the tap changer of the triangular wiring transformer cannot be tested by a direct current method in the prior art.
In order to achieve the purpose of the invention, the technical scheme adopted by the invention is as follows: a triangular connection transformer on-load tap-changer action characteristic testing device comprises:
the power supply generation module is used for pressurizing the tested triangular wiring transformer;
the voltage divider module is used for adjusting the pressurization value according to the measured triangular wiring transformer parameter;
the measurement protection module is used for performing overcurrent and overvoltage protection on the test device;
the data acquisition module is used for acquiring the total current of the three windings in the triangular wiring transformer to be detected and the three-phase voltage corresponding to the three windings;
and the central processing unit is used for performing analog-to-digital conversion on the acquired total current and voltage signals and then performing data processing.
In the above technical solution, the power generating module selects a dc constant voltage source.
In the above technical solution, the voltage divider module is a variable resistor.
In the above technical solution, the measurement protection module includes an overcurrent protection system, an overvoltage protection system, and a grounding system controlled by the central processing unit.
In the above technical solution, the data acquisition module includes a current acquisition circuit and at least three voltage acquisition circuits.
In the above technical solution, the test device further comprises a data display module for displaying the test result.
A method for testing the operating characteristics of an on-load tap-changer of a triangular wiring transformer comprises the following steps:
and 6, outputting a test result to finish the test.
In the above technical solution, the resistance value of the voltage divider in step 1 is the same magnitude as the dc resistance value of the tested delta connection transformer.
In the above technical solution, one of the two arbitrary wire end pile heads in step 2 is a pressing end, and the other is a recovery end.
In the above technical solution, in the step 5, the action time of each phase of the tap changer is determined according to the three-phase voltage oscillogram, so as to test the transition time and three-phase synchronism parameters of the tap changer, and further complete the continuity test of each phase of the tap changer by combining the total current waveform.
Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages:
1. the invention adopts a direct current test method to complete the test of the action characteristic of the on-load tap-changer of the transformer with the triangular connection mode, and makes up the technical blank that the action characteristic of the tap-changer of the transformer with the triangular connection mode can not be tested by the direct current method in the prior art;
2. the invention fully considers the safety factor, the measurement protection module of the device can perform overcurrent and overvoltage protection in the test process, and discharge the tested transformer after the test is finished, so that the instrument is prevented from being damaged by the reverse potential energy of the transformer;
3. the device has the advantages of simple design, strong practicability, high testing precision and the like, and meets the production requirements.
Drawings
Fig. 1 is a block diagram of a device according to a first embodiment of the present invention.
Fig. 2 is a flowchart of a testing method according to a first embodiment of the invention.
Fig. 3 is a test schematic of the present invention.
Fig. 4 to 10 are diagrams of the operation of the double-resistor transition tap changer according to the invention.
Fig. 11 is a graph of phase current waveforms for an ideal transition process of the present invention.
Fig. 12 is a schematic diagram of a simulation according to a first embodiment of the present invention.
Fig. 13 is a schematic diagram of a simulation voltage according to a first embodiment of the present invention.
Fig. 14 is a schematic diagram of a simulation current according to a first embodiment of the present invention.
Detailed Description
The invention is further described with reference to the following figures and examples:
the first embodiment is as follows:
referring to fig. 1, the invention discloses a device for testing the operating characteristics of an on-load tap changer of a triangular connection transformer, which comprises:
the power generation module is used for pressurizing the tested triangular wiring transformer and selects a direct-current constant-voltage source;
the voltage divider module is used for adjusting the pressurization value according to the measured triangular wiring transformer parameter, selects a variable resistor and can adjust the resistance value according to the requirement;
the measurement protection module is used for performing overcurrent and overvoltage protection on the testing device and consists of an overcurrent and overvoltage protection system and a direct grounding system controlled by the central processing unit, and in the testing process, if the overcurrent and overvoltage condition occurs in the testing device, the power supply generation module is disconnected and grounded for discharging; after the measurement is finished, the transformer has very large reverse electromotive force, so that the instrument is easily damaged, and the measurement protection circuit releases the reverse voltage of the transformer at the moment, so that the instrument is protected;
the data acquisition module is used for acquiring the total current of three windings in the tested triangular wiring transformer and the three-phase voltage corresponding to the three windings, and comprises a current acquisition circuit and at least three voltage acquisition circuits;
and the central processing unit is used for performing analog-to-digital conversion on the acquired total current and voltage signals and then performing data processing.
In this embodiment, the test device further includes a data display module for displaying the test result.
Besides, a storage module and a man-machine interaction module can be further arranged, and the storage of the test data is realized through the storage module. The man-machine interaction module can be a key, a USB flash disk interface, a printer and other peripherals or ports.
The connection mode of each module is as follows: the central processing unit is electrically connected with other modules to realize the sending and receiving of control information.
Referring to fig. 2, a method for testing the operating characteristics of an on-load tap changer of a delta connection transformer includes the following steps:
specifically, the action of the winding tap changer will cause the trend of phase voltage waveform to change, and the change has uniqueness. Taking the sequential action of the AB winding tap switches, BC winding tap switches and CA winding tap switches as an example, after the AB winding tap switches act, the voltage of the three-phase winding is increased; after the BC winding tapping switch acts, voltages of the BC winding and the AB winding are increased, and voltage of the CA winding is reduced; after the CA winding tapping switch acts, the voltages of the CA winding and the AB winding are increased, and the voltage of the BC winding is reduced; and judging the action time of each phase of the tap switch according to the three-phase voltage oscillogram so as to test the transition time and three-phase synchronism parameters of the tap switch, and further combining the total current waveform to finish the waveform continuity test of each phase of the tap switch. Thereby meeting the regulations of DL/T265 'on-load tap changer field test guide of transformer'.
And 6, outputting a test result to finish the test.
The main principle of the method is as follows:
referring to fig. 4 to 10, the on-load tap changer is a schematic diagram of the operation of the double-resistor transition tap changer, and the on-load tap changer prevents the windings from being tapped and short-circuited by connecting transition resistors R1 and R2 in series. Assume that the total resistance of the main loop of the winding is R0 and the supply voltage is U. It can be seen that during gear shifting, the sliding contact slides from K1 to K4, and the whole shifting process goes through 7 stages, namely:
a) referring to FIG. 4, at the initial time K1, the contact is turned on, and the winding phase current is U/R0；
b) Referring to FIG. 5, the contacts begin to slide, K1 and K2 are simultaneously conductive, and R1 is bypassed while the winding phase current remains U/R0；
c) Referring to fig. 6, at time t1, the K2 contact is turned on, and R1 is connected to the loop, and the winding phase current is U/(R)0+R1)；
d) Referring to fig. 7, at time t2, the K2 and K3 contacts are turned on simultaneously, and the R1 and R2 are connected into the loop and in parallel, and the winding phase current is U/(R)0+R1∥R2)；
e) Referring to fig. 8, at time t3, the K3 contact is turned on, and R2 is connected to the loop, and the winding phase current is U/(R)0+R2)；
f) Referring to FIG. 9, K3 and K4 contacts are turned on simultaneously, and R2 is bypassed when the winding phase current is U/R0；
g) Referring to FIG. 10, the K4 contact is turned on and the shift is completed while the winding phase current is still U/R0。
The duration of the whole switching process is about 40-60 ms, the trend of the loop resistance and the phase current waveform changing along with time is shown in fig. 11, and the traditional testing instrument tests the phase current waveform to realize the action characteristic test of the tap changer. However, since most of the transformers for stations adopt a triangular connection mode, the phase current cannot be measured, and the line current waveforms are superimposed, so that the testing cannot be performed.
The invention adopts a mode of monitoring the voltage of each winding to judge the action time of each phase of tapping switch. Pressurizing pile heads at any two line ends of the triangular wiring transformer by taking the pile head at the line end A for pressurization and the pile head at the line end B for recovery as an example:
a) when the tapping switch between the AB windings starts to act, as can be seen from the above analysis, the impedance between the AB windings is inevitably increased, the branch voltage of the AB windings is increased, the branch voltage of the BC and CA are also increased simultaneously, the increase amplitudes of the BC and CA are consistent, and the sum of the increase of the two branches is equal to the increase value of the branch voltage of the AB windings.
b) When the tapping switch between the BC windings starts to act, as can be known from the analysis, the impedance between the BC windings is inevitably increased, the voltage of the branch of the BC winding is increased, the partial pressure of the branch of the CA winding is reduced, the partial pressure of the branch of the AB winding is increased, and the algebraic sum of the voltage changes of the BC and the CA is equal to the added value of the partial pressure of the branch of the AB winding.
c) When the tapping switch between the CA windings starts to act, as can be known from the analysis, the impedance between the CA windings is inevitably increased, at the moment, the branch voltage of the CA windings is increased, the branch voltage of the BC windings is reduced, the branch voltage of the AB windings is increased, and the algebraic sum of the voltage changes of the CA and the BC is equal to the added value of the branch voltage of the AB windings.
The invention utilizes the characteristic that the trend of phase voltage waveform changes caused by the action of the winding tap switch and the change has uniqueness, analyzes the change trend of the collected three-phase voltage signals (local optimal algorithms such as a hill climbing method, a neural network method and the like can be adopted), thereby judging the action time of each phase tap switch and further realizing the measurement of the transition time of the tap switch and the three-phase synchronism parameters.
In the bridging process of the tap changer, if a wire break state occurs in a certain phase, the winding wire voltage of the phase will inevitably rise to the power supply voltage, and the total current will be greatly reduced. The continuity test of each phase waveform of the tap switch can be realized by the three-phase voltage variation trend and the combination of the total current waveform. Thereby meeting the test regulation of DL/T265 'transformer on-load tap-changer field test guide'.
A simulation model was constructed according to FIG. 12, in which: DC represents a direct-current constant-voltage source, R represents an adjustable resistor, TV1, TV2 and TV3 represent voltage transformers, TA represents a current transformer, T represents a three-phase transformer, and K represents a transformer transformation ratio tap switch. The three-phase transformer adopts a Dyn wiring mode (wherein the primary side is a triangular D-shaped wiring, and the secondary side is a star-shaped neutral point grounding yn-type wiring), and the triangular secondary side is in short circuit grounding. The transformation ratio of the primary side of the three-phase transformer is adjusted, and the data acquisition module acquires three-phase voltage and current waveforms through a TA and a TV. In this simulation, the dc power supply is set to 10V, R is 1 Ω, and the equivalent inductance and the equivalent resistance of the transformer winding are 32mH and 1 Ω before the transformation ratio is adjusted, and 34mH and 1.2 Ω after the transformation ratio is adjusted, respectively. The tap switch K is in a double transition resistance switching mode, A, B, C three-phase tap switches sequentially act, the action time of the A-phase tap switch is t 1-0.1 s, the action time of the B-phase tap switch is t 2-0.17 s, the action time of the C-phase tap switch is t 3-0.3 s, and the simulation time length is 0.4 s. In the switching process, the simulation waveforms of the three-phase voltages UA, UB and UC are shown in fig. 13, and the simulation waveforms of the current are shown in fig. 14.
As can be seen in fig. 13 and 14: when the phase A tapping switch acts, the three-phase voltage is increased, and after the transition process is finished, the three-phase voltage is reduced; after the phase B tapping switch acts, transient overvoltage of the phase B and the phase C can be caused because the inductive current can not suddenly change, then the A, B phase voltage is increased, and the C phase voltage is reduced; similarly, when the phase C tap switch is operated, the A, C phase voltage increases and the phase B voltage decreases. The simulation waveform is consistent with theoretical analysis, and the accuracy and the effectiveness of the method for testing the on-load tap-changer operating characteristics of the triangular wiring transformer are further verified.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to the above-described embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. The utility model provides a triangle-shaped wiring transformer on-load tap-changer action characteristic testing arrangement which characterized in that includes:
the power supply generation module is used for pressurizing the tested triangular wiring transformer;
the voltage divider module is used for adjusting the pressurization value according to the measured triangular wiring transformer parameter;
the measurement protection module is used for performing overcurrent and overvoltage protection on the test device;
the data acquisition module is used for acquiring the total current of the three windings in the triangular wiring transformer to be detected and the three-phase voltage corresponding to the three windings;
and the central processing unit is used for performing analog-to-digital conversion on the acquired total current and voltage signals and then performing data processing.
2. The apparatus of claim 1, wherein the power generation module is a dc constant voltage source.
3. The apparatus of claim 1, wherein the voltage divider module is a variable resistor.
4. The on-load tap-changer operating characteristic testing device of the delta connection transformer as claimed in claim 1, wherein the measurement protection module comprises an overcurrent protection system, an overvoltage protection system and a grounding system controlled by a central processing unit.
5. The on-load tap changer behavior testing device of claim 1, wherein the data acquisition module comprises a current acquisition circuit and at least three voltage acquisition circuits.
6. The on-load tap-changer operating characteristic testing device of the delta connection transformer as claimed in claim 1, further comprising a data display module for displaying the test result.
7. A method for testing the operating characteristics of an on-load tap-changer of a triangular wiring transformer is characterized by comprising the following steps:
step 1, adjusting the resistance value of a voltage divider according to the parameter of a tested triangular wiring transformer;
step 2, pressurizing pile heads at any two line ends of the tested triangular wiring transformer;
step 3, synchronously acquiring the total current of three windings in the tested triangular wiring transformer and the three-phase voltage corresponding to the three windings;
step 4, performing analog-to-digital conversion on the collected total current and voltage information;
step 5, processing the data;
and 6, outputting a test result to finish the test.
8. The method for testing the on-load tap-changer operating characteristics of the delta connection transformer as claimed in claim 7, wherein the resistance value of the voltage divider in the step 1 is in the same order of magnitude as the dc resistance value of the delta connection transformer to be tested.
9. The method for testing the operating characteristics of the on-load tap changer of the delta connection transformer of claim 7, wherein one of any two terminal stubs in the step 2 is a voltage-applying end, and the other terminal stub is a voltage-withdrawing end.
10. The method for testing the operating characteristics of the on-load tap-changer of the delta connection transformer as claimed in claim 7, wherein in the step 5, the operating time of each phase of the tap-changer is judged according to the three-phase voltage waveform diagram, so that the transition time and three-phase synchronism parameters of the tap-changer are tested, and the continuity test of each phase waveform of the tap-changer is further completed by combining the total current waveform.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911388150.3A CN110907819A (en) | 2019-12-30 | 2019-12-30 | Device and method for testing operating characteristics of on-load tap changer of triangular wiring transformer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911388150.3A CN110907819A (en) | 2019-12-30 | 2019-12-30 | Device and method for testing operating characteristics of on-load tap changer of triangular wiring transformer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110907819A true CN110907819A (en) | 2020-03-24 |
Family
ID=69814040
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911388150.3A Pending CN110907819A (en) | 2019-12-30 | 2019-12-30 | Device and method for testing operating characteristics of on-load tap changer of triangular wiring transformer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110907819A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112462251A (en) * | 2020-11-19 | 2021-03-09 | 广东电网有限责任公司电力科学研究院 | On-load tap-changer switching time sequence detection method |
-
2019
- 2019-12-30 CN CN201911388150.3A patent/CN110907819A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112462251A (en) * | 2020-11-19 | 2021-03-09 | 广东电网有限责任公司电力科学研究院 | On-load tap-changer switching time sequence detection method |
| CN112462251B (en) * | 2020-11-19 | 2022-02-15 | 广东电网有限责任公司电力科学研究院 | On-load tap-changer switching time sequence detection method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2738411C (en) | Wind energy plant testing device | |
| CN101291054B (en) | Diagnosis and protection method for residue current of ground fault in electrical power system | |
| CN103364754B (en) | A kind of automatic measuring transformer directly hinders, short resistance, have carry, the method for no-load voltage ratio | |
| CN201237626Y (en) | Debugging apparatus for arc suppression coil | |
| CN110703040A (en) | Distribution network single-phase earth fault positioning method based on fault phase and non-fault phase current mutation difference | |
| CN108802531B (en) | High-low voltage ride through testing device with ground short circuit function | |
| CN102087323A (en) | Arc suppression coil debugging device | |
| CN108845223A (en) | A kind of arc suppression coil magnetic control disturbance selection method | |
| CN103558536A (en) | Circuit for testing overload tolerance capacity of series capacitor and working method of circuit | |
| CN106373764A (en) | On-load capacitance and voltage regulation system of power distribution transformer | |
| KR101912150B1 (en) | Method and device for testing a tap changer of a transformer | |
| CN110907819A (en) | Device and method for testing operating characteristics of on-load tap changer of triangular wiring transformer | |
| CN201886097U (en) | Debugging device for arc-suppression coil | |
| CN101937058B (en) | Device and method for testing multi-wave fault current testing device in converter valve operating test | |
| CN211348551U (en) | Device for testing operating characteristics of on-load tap changer of triangular wiring transformer | |
| CN205157597U (en) | Power transformer's experimental pencil | |
| CN103730879A (en) | Protection device for power utilization system of transformer substation | |
| CN108037469B (en) | Airplane power supply characteristic testing system and method | |
| CN110794354A (en) | Alternating current-to-direct current function calibrator for insulation monitoring device and application method thereof | |
| CN215599288U (en) | Distribution intelligent terminal grounding performance testing device | |
| CN214622989U (en) | Arc extinction system tester | |
| CN107957539A (en) | A kind of electromagnetic potential transformer first winding tail end insulation detecting method and device | |
| CN213398738U (en) | Transformer direct resistance transformation ratio comprehensive test system | |
| CN112748371B (en) | General test structure for multiple test items of transformer test and logic control method | |
| CN108964433A (en) | A kind of overall process Inrush current restraining generalization device and control method based on PWM closed-loop control |
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 |