CN109406907B - High-impedance transformer simulation loaded through-flow test device and test method - Google Patents
High-impedance transformer simulation loaded through-flow test device and test method Download PDFInfo
- Publication number
- CN109406907B CN109406907B CN201811499769.7A CN201811499769A CN109406907B CN 109406907 B CN109406907 B CN 109406907B CN 201811499769 A CN201811499769 A CN 201811499769A CN 109406907 B CN109406907 B CN 109406907B
- Authority
- CN
- China
- Prior art keywords
- phase
- frequency
- current
- voltage
- transformer
- 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.)
- Active
Links
- 238000012360 testing method Methods 0.000 title claims abstract description 44
- 238000004088 simulation Methods 0.000 title claims abstract description 10
- 238000010998 test method Methods 0.000 title claims abstract description 10
- 238000005259 measurement Methods 0.000 claims abstract description 24
- 230000009466 transformation Effects 0.000 claims abstract description 10
- 238000010586 diagram Methods 0.000 claims abstract description 8
- 238000002955 isolation Methods 0.000 claims abstract description 8
- 238000012545 processing Methods 0.000 claims description 26
- 238000000034 method Methods 0.000 claims description 16
- 238000001914 filtration Methods 0.000 claims description 12
- 238000004891 communication Methods 0.000 claims description 11
- 230000001939 inductive effect Effects 0.000 claims description 7
- 230000003321 amplification Effects 0.000 claims description 5
- 238000003199 nucleic acid amplification method Methods 0.000 claims description 5
- 238000006243 chemical reaction Methods 0.000 claims description 4
- 238000001514 detection method Methods 0.000 claims description 4
- 230000008569 process Effects 0.000 claims description 4
- 238000005070 sampling Methods 0.000 claims description 3
- 238000012795 verification Methods 0.000 claims description 3
- 238000004364 calculation method Methods 0.000 description 5
- 230000001965 increasing effect Effects 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
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
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/20—Measuring number of turns; Measuring transformation ratio or coupling factor of windings
-
- 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
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Testing Relating To Insulation (AREA)
Abstract
A high impedance transformer simulation load through-flow test device and test method, including electronic three-phase wide frequency voltage source and three-phase power frequency heavy current booster, wide frequency wireless phase telemetering device; the output end of the electronic three-phase broadband voltage source is connected with a three-phase power frequency heavy current booster, and the three-phase power frequency heavy current booster consists of three isolation transformers with the same specification and model; before measurement, time calibration is carried out on a host machine and an extension machine of the broadband wireless telemetering phase device, power frequency through flow and low frequency through flow are carried out, and the correctness of a differential protection hexagonal diagram is detected; measuring the transformation ratio, judging the correctness of the transformation ratio and the polarity and carrying out differential flow operation; the invention ensures the safe and stable operation of the system and improves the success rate of one-time operation.
Description
Technical Field
The invention relates to the field of relay protection, in particular to a high-impedance transformer simulation loaded through-flow test device and a test method.
Background
2018, eighteen requirements of important anti-accident measures (revised version) of the power grid of national grid company Limited on relay protection operation management: before all protection current loops are put into operation, the unbalanced current (or voltage) of each neutral line must be measured to ensure the correctness of the wiring of a protection device and a secondary loop, besides the correct measurement of transformation ratio, polarity and the phase relation of the current loop and the voltage loop under the condition that the load current meets the precision of a current transformer and the precision of a measuring meter.
With the development of power systems, the capacity of a single transformer is larger, and an autotransformer (including a step-up transformer and a start-up transformer of a power plant) with the voltage of more than 1000MVA/500kV is higher in short-circuit impedance (more than 100 ohms) and larger in bushing CT ratio (4000/1). Most of the existing three-phase through-current test methods can only realize through-current of a bus loop, 380V for overhauling a power box in a station is basically adopted for the through-current of a transformer to directly supply power or realize the through-current of the high-voltage side of the transformer in a boosting mode (2kV), even if the current on the primary side of the transformer can only be added to a few amperes, the current can be often limited by the capacity of a power supply in the station, the current on the secondary side of a CT can only reach 0.5-2 mA, the highest resolution of the secondary current measured by a display screen of a protection device is only 10mA, the secondary current value generated by 380V voltage applied by power frequency cannot be read at all, the safety and the field operability of equipment during application are necessarily influenced by increasing the capacity of the test power supply in the boosting mode, and. Due to the wide impedance range (1.5-200) of the transformer, the on-load polarity test of the transformer can only be measured after the transformer is put into operation, so that the risk of equipment operation is brought.
Disclosure of Invention
The invention provides a high-impedance transformer simulation loaded through-flow test device and a test method for solving the problems that the applied current is small when a power frequency through-flow test is carried out due to overhigh impedance of a transformer, and the phase and amplitude of the current of a secondary loop cannot be measured normally.
The technical solution of the invention is as follows:
a high-impedance transformer simulation loaded through-flow test device comprises an electronic three-phase broadband voltage source, a three-phase power frequency heavy current booster and a broadband wireless phase remote measuring device; the output end of the electronic three-phase broadband voltage source is connected with a three-phase power frequency heavy current booster, and the three-phase power frequency heavy current of the booster consists of three isolation transformers with the same specification and model.
Furthermore, the broadband wireless phase telemetering device comprises a host and an extension, wherein the host and the extension simultaneously comprise a signal acquisition module, a signal amplification module, an analog-to-digital conversion module, a data processing module and a wireless communication module, and the host data processing module and the extension data processing module respectively adopt a single chip microcomputer with a floating point calculation function and are respectively provided with a time calibration port; a calibration line is arranged between a time calibration port of a host data processing module and a time calibration port of an extension data processing module, the host data processing module outputs time reference pulses, and the extension data processing module completes time calibration by receiving the time reference pulses sent by a host to realize synchronization.
Furthermore, the electronic three-phase broadband voltage source comprises a three-phase alternating current input end, a high-voltage direct current circuit, an H-bridge circuit, a PWM control chip and a three-order sine filter circuit;
the three-phase alternating current is a three-phase power supply, high-voltage direct current is obtained after rectification and filtering, the amplitude of the high-voltage direct current circuit is 565V, the rectified and filtered bus voltage is added to two ends of an H bridge driven by a PWM control chip to generate high-frequency voltage, and the high-frequency voltage output by the H bridge circuit outputs required voltage through a three-order sine filter circuit;
the H-bridge circuit inverts the direct current into alternating current with a certain frequency or variable frequency through the opening and closing of a switch, and the switch of the H-bridge circuit is controlled by a PWM control chip;
the PWM control chip is an SPWM sine pulse width modulation chip;
the output end of the H-bridge circuit is connected with a third-order sine filter circuit, the host data processing module and the extension data processing module process sampling data in a DSP digital filtering mode, and frequency selection and broadband measurement are achieved.
A high-impedance transformer simulation loaded through-flow test method is characterized in that:
the method comprises the following steps: before measurement, time calibration is firstly carried out on a host and an extension of the broadband wireless telemetering phase device, and the specific operation mode is as follows:
1. respectively inserting the calibration lines into the host calibration port and the used extension calibration ports;
2. setting the host computer on a communication measurement interface, and setting the extension set on a current communication measurement interface;
3. the system automatically checks and makes a check completion prompt;
4. pulling out the calibration line, completing the verification and continuing the subsequent measurement;
step two: completing wiring operation according to the wiring requirement;
step three: power frequency through-flow
The output end of the three-phase large-current booster is connected with a bus interval three-phase loop in the station, the host of the broadband wireless phase telemetering device selects any one-phase CT secondary current as a reference, and the phase and the amplitude of the CT secondary current of a three-phase switch of the interval loop are measured by the extension set and sent to the host;
step four: low frequency through-flow
The method comprises the steps that a primary loop of a low-voltage side of a transformer is short-circuited through a bus grounding switch, an electronic three-phase broadband voltage source is started to pressurize a low frequency of the high-voltage side of the transformer, and the test frequency and the output voltage are adjusted according to a bushing CT secondary loop current detected by a broadband wireless telemetering phase device, so that the amplitude of the bushing CT secondary current of the high-voltage side and the low-voltage side of the transformer meets the requirement of test precision;
the extension set respectively sends the amplitude of the secondary current of the high-low voltage side bushing CT of the transformer and phase information of the reference datum of the host to the host, and the correctness of the differential protection hexagonal diagram is detected;
step five: drawing a hexagonal relation graph according to the phase and amplitude information sent by the extension set, measuring the transformation ratio, judging the correctness of the transformation ratio and the polarity, and performing differential flow operation.
Furthermore, the low-frequency parts of the electronic three-phase broadband voltage source and the broadband wireless phase telemetering device are adopted, and the output frequency of the electronic three-phase broadband voltage source and the detection frequency of the wireless phase telemetering device are both less than 5 Hz.
Further, the theoretical basis of the test for simulating the loaded through-flow by adopting the low-frequency ride through transformer is that the short-circuit impedance of the transformer is inductive, and the impedance value is in direct proportion to the test frequency.
Furthermore, the current applied to the transformer by the electronic three-phase broadband voltage source is less than 10% of the rated current, and the output of the voltage amplitude is automatically controlled after the test frequency is selected to ensure that the transformer core and the bushing CT cannot be subjected to low-frequency saturation.
Further, in the fourth step, the voltage of the test device is adjusted to enable the low-frequency current of the primary loop to reach more than 10A, and the secondary current of the CT on the two sides of the transformer bushing exceeds 10 mA.
The primary through-flow test method and the test equipment for the high-impedance transformer disclosed by the invention can complete the detection of the current phase of each winding and the integrity of the current loop when the current loop of the secondary protection device is complete and the current test is carried out before production, thereby avoiding the possibility of current phase error after the equipment is electrified, ensuring the safe and stable operation of a system and improving the success rate of primary operation. The beneficial results are as follows:
1. the invention can reduce the power supply capacity by tens of times and is convenient for field transportation;
2. the three-phase broadband voltage source, the three-phase power frequency heavy current booster and the broadband wireless phase remote measuring device adopt a split structural design, so that the weight of equipment is further reduced, and the field operability is improved;
3. the electronic three-phase broadband voltage source adopts a three-order filtering mode, and the voltage output end does not need to be additionally provided with an isolation transformer, so that the weight of equipment is greatly reduced;
the broadband wireless phase telemetering device can track the test frequency and measure the amplitude of each phase of the secondary current of the high-low voltage bushing CT of the transformer, and draw a hexagonal graph of differential protection according to the phase relation between the amplitude and a reference datum; and wireless transmission is adopted, so that potential safety hazards caused by introducing voltage reference dragging lines are avoided.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the application and, together with the description, serve to explain the application and are not intended to limit the application. The invention is further elucidated with reference to the drawing.
FIG. 1 is a schematic diagram of an electronic three-phase broadband voltage source;
FIG. 2 is a schematic diagram of a wideband wireless phase telemetry apparatus;
fig. 3 is a wiring diagram of the primary through-flow test device of the high-impedance transformer.
Detailed Description
As shown in fig. 3, the high impedance transformer simulation loaded through-flow test device of the present invention comprises an electronic three-phase wide-frequency voltage source, a three-phase power frequency large current booster and a wide-frequency wireless phase remote measuring device;
as shown in fig. 1, the electronic three-phase wide-band voltage source is composed of a three-phase ac input terminal, a high-voltage dc circuit, an H-bridge circuit, a PWM control chip, and a three-order sine filter circuit.
The alternating current is a three-phase power supply, high-voltage direct current is obtained after rectification and filtering, the amplitude of the high-voltage direct current is 565V, the rectified and filtered bus voltage is applied to two ends of an H-bridge circuit driven by a PWM control chip to generate high-frequency voltage, and the high-frequency voltage output by the H-bridge circuit outputs required voltage through a three-order sine filter circuit.
The H-bridge circuit can reverse the voltage or current at two ends of a load or an output end connected with the H-bridge circuit, thereby playing the role of an inverter, inverting the direct current into alternating current with certain frequency or variable frequency by opening and closing a switch, and controlling the switch by a PWM control chip.
With a PWM control chip, specifically SPWM sinusoidal pulse width modulation, SPWM equates sinusoidal waveforms (amplitude, phase and frequency) by modulating a series of pulses of unequal width. By adopting the working mode, the problem that the carbon brush of the contact voltage regulator is easy to damage is solved, and meanwhile, the electronic driving switch has a thermal protection function and can run under full load for a long time.
The high-frequency voltage output by the electronic three-phase broadband voltage source at the output end of the power tube of the H-bridge circuit is filtered in a three-order mode, so that the steeper the boundary between a pass band and a stop band on a frequency curve of the filter is ensured, the higher the selectivity of the filter is, the characteristics of low output impedance and filtering effect are achieved, and an isolation transformer is not required to be added. The output broadband voltage frequency after the broadband voltage source filters is 0.5Hz-300Hz, the output voltage is 380V, and the output current is 50A.
The output end of the electronic three-phase wide-frequency voltage source is connected with a three-phase power-frequency heavy-current booster, the current booster consists of three isolation transformers with the same specification and model, the transformation ratio of the input end to the output end is 20:1, the input voltage of the port of the current booster reaches 380V, the output voltage of the port of the current booster is close to 20V, and the single-phase output current reaches 200A, so that the current booster covers the existing power-frequency through-flow test of a bus circuit.
The invention adopts an electronic three-phase broadband voltage source to apply a current less than 10% of the rated current to the transformer, and can automatically control the output of the voltage amplitude value after selecting the test frequency to ensure that the transformer core and the bushing CT can not have low-frequency saturation.
The electronic three-phase broadband voltage source can output 0.5Hz-300Hz three-phase symmetrical alternating current signals which are 120 degrees mutually, output voltage is 380V and rated output current is 50A, and the use requirement can be met by supplying power by three-phase alternating current in a maintenance power box in a transformer substation; the three-order filtering mode is adopted for working, the standard sine wave has the characteristics of low output impedance and good filtering effect, and an isolation transformer is not required to be added for isolation filtering; the SPWM is adopted to control the high-frequency switch to work, the working mode solves the problem that a carbon brush of a contact voltage regulator is easy to damage, and the electronic driving switch has a thermal protection function and can work under full load for a long time.
As shown in fig. 2, the broadband wireless phase telemetry apparatus includes a host and an extension, the host and the extension respectively include a signal acquisition module, a signal amplification module, an analog-to-digital conversion module, a data processing module and a wireless communication module, the host data processing module and the extension data processing module respectively adopt a single chip microcomputer (STM32F4 series) with a floating point calculation function, and are respectively provided with a time calibration port; a calibration line is arranged between a time calibration port of a host data processing module and a time calibration port of an extension data processing module, the host data processing module outputs time reference pulses, the extension data processing module completes time calibration by receiving the time reference pulses sent by a host, and then a time reference connecting line can be disconnected to realize time synchronization of the host and the extension.
The host machine selects voltage or current as reference, the main machine and the extension machine automatically track the frequency of the applied voltage or current to realize the measurement of the phase and the amplitude of the low-frequency signal, and the host machine can receive a plurality of groups of measurement data of the extension machine and display the phase relation, namely a hexagonal graph, on a color screen.
The signal acquisition module comprises the acquisition of voltage signals and the acquisition of current signals, the voltage signals are acquired through a voltage division mode, and the current signals are clamped on a CT secondary terminal wire through an open type current clamp to induce secondary current signals.
And the signal amplification module selects a proper amplification factor according to the anti-interference capability of the signal and the voltage reference of the analog-to-digital conversion module and performs digital filtering processing on the high-frequency signal.
The host data processing and extension data processing modules process sampled data in a DSP digital filtering mode, specifically, discrete sampling points are subjected to discrete Fourier transform, time domain signals are converted into frequency domain signals, and frequency selection and broadband measurement are achieved.
The wireless communication module adopts a low-frequency 170MHz half-duplex communication mode, can easily pass through barriers such as a wall body and shielding, and realizes remote data transmission.
The host and the extension of the broadband wireless phase telemetering device can automatically track the frequency of voltage or current, and the measurement of the phase and the amplitude of a low-frequency signal is realized.
The host computer of the broadband wireless phase telemetering device adopts a 7-inch color screen for display, can accept and process a plurality of groups of measurement data, and draws a hexagonal phase relation graph according to the measurement data.
In field application, the output end of an electronic three-phase broadband voltage source is connected with the high-voltage side of a transformer, a main machine current clamp of the broadband wireless phase telemetering device is clamped on the secondary of a bushing CT on the high-voltage side of the transformer by taking the A phase as a reference standard, and current clamps of the extension set are respectively clamped on the secondary of the bushing CT on the low-voltage side of the transformer to respectively test three phases.
The high-impedance transformer simulation loaded through-flow test method comprises the following steps:
the method comprises the following steps: before measurement, time calibration is firstly carried out on a host and an extension of the broadband wireless telemetering phase device, and the specific operation mode is as follows:
1. respectively inserting the calibration lines into the host calibration port and the used extension calibration ports;
2. setting the host computer on a communication measurement interface, and setting the extension set on a current communication measurement interface;
3. the system automatically checks and makes a check completion prompt;
4. and pulling out the calibration line, completing the verification and continuing the subsequent measurement.
Step two: the wiring operation shown in fig. 2 is performed according to the wiring requirements.
Step three: power frequency through-flow
The output end of the three-phase large-current booster is connected with a bus interval three-phase loop in the station, the host of the broadband wireless phase telemetering device selects any one-phase CT secondary current as a reference, and the phase and the amplitude of the CT secondary current of a three-phase switch of the interval loop are measured by the extension set and sent to the host;
step four: low frequency through-flow
The method comprises the steps that a primary loop of a low-voltage side of a transformer is short-circuited through a bus grounding switch, an electronic three-phase broadband voltage source is started to pressurize a low frequency of the high-voltage side of the transformer, and the test frequency and the output voltage are adjusted according to a bushing CT secondary loop current detected by a broadband wireless telemetering phase device, so that the amplitude of the bushing CT secondary current of the high-voltage side and the low-voltage side of the transformer meets the requirement of test precision;
the extension set respectively sends the amplitude of the secondary current of the high-low voltage side bushing CT of the transformer and phase information of the reference datum of the host to the host, and the correctness of the differential protection hexagonal diagram is detected;
step five: drawing a hexagonal relation graph according to the phase and amplitude information sent by the extension set, setting a transformation ratio, judging the correctness of the transformation ratio and polarity, and performing differential flow calculation.
Low frequency through-flow test basis:
short-circuit impedance of large transformerAnd (2) assuming that the inductive component is n times of the resistive component under the power frequency condition (the value of n depends on the transformer parameters, and can reach tens of times or even tens of times under the power frequency condition), calculating the impedance according to the impedance calculation formulaWhen f is 50Hz, the inductive reactance is X0100 pi L is n times the resistance, at which the impedance value approaches the inductive reactance value. When f is a low frequency m, the inductive reactance is X1And (2) taking m as 5Hz, wherein the impedance value of the transformer is reduced by nearly 10 times, the primary test current of the transformer under the voltage equivalent to the power frequency of 50Hz is increased by 10 times, the impedance reduction is more obvious along with the reduction of the frequency, and the injected current is linearly increased.
The invention utilizes the inductive characteristic of the short-circuit impedance of the transformer and adopts the low-frequency power supply to simulate the loaded through-current, and mainly solves the problems that the applied current is small and the current amplitude and the phase of the secondary loop cannot be measured normally during the power frequency through-current test.
The device is used for carrying out hexagonal vector diagram detection on the wiring of a 2 x 35MW newly-built 1# starting transformer differential protection device of the Liaoning Datang International cucurbit island thermoelectric Limited company. The three-phase power supply of the device sets a 5Hz test frequency to be applied from a 220kV line side (a high-voltage side of a transformer), a double-inlet bus of a generator at a 6.3kV side is all in short circuit grounding, so that test current passes through the transformer to generate low-frequency short circuit current at two low-voltage sides, the amplitude and the phase of each phase of current are secondarily tested by a high-voltage bushing CT (current transformer) and a low-voltage bushing CT (current transformer), and the wiring and the differential current calculation of a differential protection loop of the transformer. The correctness of the low-frequency three-phase through-flow theory is verified by comparing the low-frequency measurement data with the power frequency measurement data.
The above description is only exemplary of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (7)
1. A high-impedance transformer simulation loaded through-flow test method is characterized in that:
the method comprises the following steps: the high-impedance transformer is adopted to simulate a loaded through-flow test device, and the high-impedance transformer is adopted to simulate the loaded through-flow test device and comprises an electronic three-phase broadband voltage source, a three-phase power frequency heavy current booster and a broadband wireless phase remote measuring device; the output end of the electronic three-phase broadband voltage source is connected with a three-phase power frequency heavy current booster, and the three-phase power frequency heavy current of the booster is composed of three isolation transformers with the same specification and model; the broadband wireless phase telemetering device comprises a host and an extension, wherein the host and the extension respectively comprise a signal acquisition module, a signal amplification module, an analog-to-digital conversion module, a data processing module and a wireless communication module; a calibration line is assembled between a time calibration port of a host data processing module and a time calibration port of an extension data processing module, the host data processing module outputs time reference pulses, and the extension data processing module completes time calibration by receiving the time reference pulses sent by a host to realize synchronization;
step two: before measurement, time calibration is firstly carried out on a host and an extension of the broadband wireless telemetering phase device, and the specific operation mode is as follows:
respectively inserting the calibration lines into the host calibration port and the used extension calibration ports;
setting the host computer on a communication measurement interface, and setting the extension set on a current communication measurement interface;
the system automatically checks and makes a check completion prompt;
pulling out the calibration line, completing the verification and continuing the subsequent measurement;
step three: completing wiring operation according to the wiring requirement;
step four: power frequency through-flow
The output end of the three-phase large-current booster is connected with a bus interval three-phase loop in the station, the host of the broadband wireless phase telemetering device selects any one-phase CT secondary current as a reference, and the phase and the amplitude of the CT secondary current of a three-phase switch of the interval loop are measured by the extension set and sent to the host;
step five: low frequency through-flow
The method comprises the steps that a primary loop of a low-voltage side of a transformer is short-circuited through a bus grounding switch, an electronic three-phase broadband voltage source is started to pressurize a low frequency of the high-voltage side of the transformer, and the test frequency and the output voltage are adjusted according to a bushing CT secondary loop current detected by a broadband wireless telemetering phase device, so that the amplitude of the bushing CT secondary current of the high-voltage side and the low-voltage side of the transformer meets the requirement of test precision;
the extension set respectively sends the amplitude of the secondary current of the high-low voltage side bushing CT of the transformer and phase information of the reference datum of the host to the host, and the correctness of the differential protection hexagonal diagram is detected;
step six: drawing a hexagonal relation graph according to the phase and amplitude information sent by the extension set, measuring the transformation ratio, judging the correctness of the transformation ratio and the polarity, and performing differential flow operation.
2. The method for simulating a loaded through-flow test of a high impedance transformer according to claim 1, wherein: the low-frequency parts of the electronic three-phase broadband voltage source and the broadband wireless phase telemetering device are adopted, and the output frequency of the electronic three-phase broadband voltage source and the detection frequency of the wireless phase telemetering device are both less than 5 Hz.
3. The method for simulating a loaded through-flow test of a high impedance transformer according to claim 1, wherein: the theoretical basis of the test for simulating the on-load through-flow by adopting the low-frequency ride through transformer is that the short-circuit impedance of the transformer is inductive, and the impedance value is in direct proportion to the test frequency.
4. The method for simulating a loaded through-flow test of a high impedance transformer according to claim 1, wherein: the current applied to the transformer by the electronic three-phase broadband voltage source is less than 10% of the rated current, and the output of the voltage amplitude is automatically controlled after the test frequency is selected to ensure that the transformer core and the bushing CT cannot be subjected to low-frequency saturation.
5. The method for simulating a loaded through-flow test of a high impedance transformer according to claim 1, wherein: in the fourth step, the voltage of the test device is adjusted to enable the low-frequency current of the primary loop to reach more than 10A, and the secondary current of the CT on the two sides of the transformer bushing exceeds 10 mA.
6. The method for simulating a loaded through-flow test of a high impedance transformer according to claim 1, wherein: the electronic three-phase broadband voltage source in the first step is composed of a three-phase alternating current input end, a high-voltage direct current circuit, an H-bridge circuit, a PWM control chip and a three-order sine filter circuit;
the three-phase alternating current is a three-phase power supply, high-voltage direct current is obtained after rectification and filtering, the amplitude of the high-voltage direct current circuit is 565V, the rectified and filtered bus voltage is added to two ends of an H bridge driven by a PWM control chip to generate high-frequency voltage, and the high-frequency voltage output by the H bridge circuit outputs required voltage through a three-order sine filter circuit;
the H-bridge circuit inverts the direct current into alternating current with a certain frequency or variable frequency through the opening and closing of a switch, and the switch of the H-bridge circuit is controlled by a PWM control chip;
the PWM control chip is an SPWM sine pulse width modulation chip;
and the output end of the H-bridge circuit is connected with a third-order sine filter circuit.
7. The method for simulating a loaded through-flow test of a high impedance transformer according to claim 1, wherein: in the first step, the host data processing module and the extension data processing module both adopt a DSP digital filtering mode to process the sampling data, so as to realize frequency selection and broadband measurement.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201811499769.7A CN109406907B (en) | 2018-12-09 | 2018-12-09 | High-impedance transformer simulation loaded through-flow test device and test method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201811499769.7A CN109406907B (en) | 2018-12-09 | 2018-12-09 | High-impedance transformer simulation loaded through-flow test device and test method |
Publications (2)
Publication Number | Publication Date |
---|---|
CN109406907A CN109406907A (en) | 2019-03-01 |
CN109406907B true CN109406907B (en) | 2021-03-02 |
Family
ID=65458006
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201811499769.7A Active CN109406907B (en) | 2018-12-09 | 2018-12-09 | High-impedance transformer simulation loaded through-flow test device and test method |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN109406907B (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111208373B (en) * | 2020-02-20 | 2023-04-07 | 中国电力科学研究院有限公司 | Mutual load method-based transformer rated operation condition simulation method and system |
CN114280392A (en) * | 2020-09-28 | 2022-04-05 | 国网安徽省电力有限公司阜阳供电公司 | Main transformer simulation load test system |
CN113030620A (en) * | 2021-03-16 | 2021-06-25 | 马鞍山钢铁股份有限公司 | Transformer differential protection phasor test system and method |
CN114062875A (en) * | 2021-11-18 | 2022-02-18 | 株洲时代新材料科技股份有限公司 | Device and method for testing impedance characteristics of rail insulation and parts thereof |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006084203A (en) * | 2004-09-14 | 2006-03-30 | Mitsubishi Electric Engineering Co Ltd | Direct-current grounding warning device |
CN201141903Y (en) * | 2007-12-14 | 2008-10-29 | 浙江省送变电工程公司 | Load test instrument of three-phase through-flow simulation belt of transforming station |
CN203465372U (en) * | 2013-09-30 | 2014-03-05 | 福建省电力工程承包公司 | Once through-flow three-phase simultaneous measurement detector for transformer station device |
CN104730408B (en) * | 2015-03-03 | 2017-11-14 | 国家电网公司 | A kind of method for verifying high-power transformer differential circuit correctness |
CN206208997U (en) * | 2016-11-15 | 2017-05-31 | 甘肃送变电工程公司 | A kind of transforming plant primary flow device |
CN207281271U (en) * | 2017-10-19 | 2018-04-27 | 中国南方电网有限责任公司超高压输电公司柳州局 | A kind of secondary through-flow instrument of portable type current transformer |
CN210109220U (en) * | 2018-12-09 | 2020-02-21 | 国网辽宁省电力有限公司锦州供电公司 | High-impedance transformer simulation loaded through-flow test device |
-
2018
- 2018-12-09 CN CN201811499769.7A patent/CN109406907B/en active Active
Also Published As
Publication number | Publication date |
---|---|
CN109406907A (en) | 2019-03-01 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN109406907B (en) | High-impedance transformer simulation loaded through-flow test device and test method | |
CN210109220U (en) | High-impedance transformer simulation loaded through-flow test device | |
CN101699301B (en) | Method for measuring line parameter through induced electricity | |
CN102680798A (en) | Online measurement method and device for grounding resistor of rod tower | |
CN102116803A (en) | Method for testing capacitance and dielectric loss value of 220KV coupling capacitor | |
CN105891606A (en) | Device for testing tower grounding resistance through disassembly-free ground lead | |
CN111879996A (en) | Transient overvoltage back-calculation method based on electromagnetic voltage transformer | |
CN117630583B (en) | Control method of power distribution network capacitance current and ground resistance detection device | |
CN104122452B (en) | Large grounded screen power-frequency grounding impedance measurement method based on multiple-synchronous different-frequency method | |
CN106324397A (en) | Ultrahigh-voltage direct-current transmission project converter transformer alternating-current loop system on-site inspection method | |
CN103424627B (en) | The method of double-end measurement parallel grid line zero-sequence impedance | |
RU112525U1 (en) | AUTOMATED DIAGNOSTIC AND MONITORING SYSTEM OF POWER CABLE LINES INSULATION | |
CN108181600B (en) | Capacitor voltage transformer testing device | |
CN205920179U (en) | High voltage transmission lines construction grounding detection device | |
CN111157924A (en) | System and method for measuring and eliminating residual magnetic chain of three-phase transformer core | |
CN103954869B (en) | Cable power frequency parameter testing device based on PXI system | |
CN207380190U (en) | A kind of iron core reactor turn-to-turn defect tests circuit | |
CN202748409U (en) | Line power frequency parameter measuring apparatus capable of eliminating power frequency interference | |
CN113985338A (en) | Primary loop optimization and modeling method for field broadband test of direct current transformer | |
CN205787992U (en) | Constant-current source control system | |
CN104361802A (en) | Electrical operation simulation device for capacitive equipment | |
CN104345218A (en) | Reactance value measurement system and method for three-phase reactor | |
CN203572898U (en) | Novel on-line monitoring device for current transformer | |
CN203587699U (en) | Insulation resistance testing device | |
CN109839536B (en) | Transformer substation CVT harmonic measurement judgment device |
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 | ||
GR01 | Patent grant | ||
GR01 | Patent grant |