CN220709338U - Voltage transformer parameter experiment and secondary circuit test system - Google Patents
Voltage transformer parameter experiment and secondary circuit test system Download PDFInfo
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- CN220709338U CN220709338U CN202321509160.XU CN202321509160U CN220709338U CN 220709338 U CN220709338 U CN 220709338U CN 202321509160 U CN202321509160 U CN 202321509160U CN 220709338 U CN220709338 U CN 220709338U
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- 238000012360 testing method Methods 0.000 title claims abstract description 131
- 238000002474 experimental method Methods 0.000 title claims abstract description 10
- 238000004891 communication Methods 0.000 claims abstract description 17
- 238000004804 winding Methods 0.000 claims description 27
- 230000005284 excitation Effects 0.000 claims description 9
- 230000009466 transformation Effects 0.000 claims description 9
- 238000012795 verification Methods 0.000 abstract description 4
- 230000010354 integration Effects 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 11
- 238000005259 measurement Methods 0.000 description 8
- 238000000034 method Methods 0.000 description 8
- 230000008569 process Effects 0.000 description 6
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- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
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- 230000009286 beneficial effect Effects 0.000 description 1
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Abstract
The utility model belongs to the technical field of transformer testing, and discloses a voltage transformer parameter experiment and secondary circuit testing system which comprises a testing host, wherein the testing host comprises a plurality of interfaces, a signal acquisition unit, an analog-digital converter and a processor unit; the signal acquisition unit is in communication connection with the interfaces, and the signal acquisition unit, the analog-digital converter and the processor unit are in communication connection in sequence. The testing system can realize the testing of multiple groups of functions of the voltage transformer, has the advantages of simple hardware structure, high intelligent degree, high integration level, high verification speed, simple and convenient operation, and can be widely applied to the testing of the voltage transformers of substations of various grades.
Description
Technical Field
The utility model belongs to the technical field of transformer testing, and particularly relates to a voltage transformer parameter experiment and secondary circuit testing system.
Background
As shown in FIG. 1, the current voltage transformer parameter test and secondary circuit inspection method is complicated, the conclusion is not accurate enough, and the requirements on the skills of inspectors are high. For example, the existing secondary loop test of the voltage transformer includes an excitation characteristic test, a load test, a polarity test, a direct current resistance test, and a transformation ratio test.
In the test items such as the excitation characteristic, the polarity test, the direct current resistance test and the transformation ratio test of the secondary circuit, a plurality of groups of measuring instruments are needed, the wire is repeatedly disconnected and connected, the operation is complex, and no instrument and no test method for testing the load of the secondary circuit exist in the prior art.
When the voltage transformer is tested, a plurality of instruments such as a booster, a standard voltage transformer, a volt-ampere characteristic tester, a universal meter and the like are required to be configured, so that a plurality of inconveniences are brought to the testing work of the voltage transformer, and a plurality of resource wastes are caused.
In summary, the secondary circuit inspection of the voltage transformer in the current stage needs more instruments, and the testing method is tedious and wastes time.
Disclosure of Invention
Aiming at the problems, the utility model provides a voltage transformer parameter experiment and secondary circuit test system, which adopts the following technical scheme:
the voltage transformer parameter experiment and secondary circuit test system comprises a test host, wherein the test host comprises a plurality of interfaces, a signal acquisition unit, an analog-digital converter and a processor unit;
the signal acquisition unit is in communication connection with the interfaces, and the signal acquisition unit, the analog-digital converter and the processor unit are in communication connection in sequence.
Further, the test host further comprises a housing, the signal acquisition unit, the analog-digital converter and the processor unit are all arranged in the housing, a plurality of interfaces are arranged on the housing, and the interfaces comprise a first interface K1, a second interface K2, a third interface S1, a fourth interface S2, a fifth interface P1 and a sixth interface P2.
Further, when the transformation ratio and polarity test of the voltage transformer is performed, the third interface S1 is connected with the primary side a end of the voltage transformer to be tested, the fourth interface S2 is connected with the primary side X end of the voltage transformer to be tested, the fifth interface P1 is connected with the secondary side a end of the voltage transformer to be tested, and the sixth interface P2 is connected with the secondary side X end of the voltage transformer to be tested.
Further, when the excitation characteristic of the voltage transformer is tested, the third interface S1 is connected to the a end of the secondary side of the voltage transformer to be tested, and the fourth interface S2 is connected to the x end of the secondary side of the voltage transformer to be tested.
Further, when the secondary circuit line judgment test of the voltage transformer is performed, the first interface K1, the second interface K2, the third interface S1 and the fourth interface S2 are respectively connected with the end a, the end B, the end C and the end N of the secondary circuit to be tested in a one-to-one correspondence manner.
Further, when the secondary side load of the voltage transformer is measured, the third interface S1 and the fourth interface S2 are respectively connected with two ends of the secondary side load.
Further, when the direct current resistance test of the secondary side winding of the voltage transformer is performed, the first interface K1 and the second interface K2 are respectively connected with two ends of the secondary side winding.
Further, the test system also comprises a printer and a display screen, wherein the printer and the display screen are both in communication connection with the test host.
Further, the processor unit comprises a digital signal processor and a micro control unit, the analog-digital converter is in communication connection with the digital signal processor, and the display screen and the printer are both in communication connection with the micro control unit.
Further, the test host also comprises a storage unit, and the storage unit is in communication connection with the digital signal processor and the micro control unit.
The utility model has the beneficial effects that: the testing system can realize the testing of multiple groups of functions of the voltage transformer, has the advantages of simple hardware structure, high intelligent degree, high integration level, high verification speed, simple and convenient operation, and can be widely applied to the testing of the voltage transformers of substations of various grades.
Additional features and advantages of the utility model will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the utility model. The objectives and other advantages of the utility model may be realized and attained by the structure particularly pointed out in the written description and drawings.
Drawings
In order to more clearly illustrate the embodiments of the present utility model or the technical solutions of the prior art, the following description will briefly explain the drawings used in the embodiments or the description of the prior art, and it is obvious that the drawings in the following description are some embodiments of the present utility model, and other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 shows a schematic diagram of a voltage transformer parametric test and secondary loop test flow according to the prior art;
FIG. 2 is a schematic diagram of a voltage transformer parameter experiment and secondary loop test system according to an embodiment of the utility model;
FIG. 3 shows a schematic diagram of a transformation ratio and polarity test interface for a voltage transformer in accordance with an embodiment of the present utility model;
FIG. 4 shows a schematic diagram of a transformation ratio and polarity test flow for a voltage transformer in accordance with an embodiment of the present utility model;
FIG. 5 shows a schematic diagram of an excitation characteristics testing interface connection for a voltage transformer according to an embodiment of the present utility model;
fig. 6 shows a schematic diagram of a flow of testing excitation characteristics of a voltage transformer according to an embodiment of the utility model;
fig. 7 shows a schematic diagram of secondary loop line testing interface connection for a voltage transformer according to an embodiment of the utility model;
fig. 8 shows a schematic diagram of a secondary loop line judgment test flow for a voltage transformer according to an embodiment of the utility model;
FIG. 9 illustrates a secondary side load measurement interface connection schematic for a voltage transformer in accordance with an embodiment of the utility model;
fig. 10 shows a schematic diagram of a secondary side load measurement procedure for a voltage transformer according to an embodiment of the utility model;
FIG. 11 shows a schematic diagram of a secondary side winding DC resistance test interface connection for a voltage transformer in accordance with an embodiment of the utility model;
fig. 12 shows a schematic diagram of a flow chart of a secondary side winding dc resistance test of a voltage transformer according to an embodiment of the utility model.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present utility model more apparent, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model, and it is apparent that the described embodiments are some embodiments of the present utility model, but not all embodiments of the present utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.
It should be noted that the terms "first," "second," and the like herein are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order.
The embodiment of the utility model provides a comprehensive test system for a voltage transformer parameter test and a voltage transformer secondary circuit of a transformer substation, which enables a test method to be comprehensive, accurate, convenient and reliable, achieves the aim of improving working efficiency, and can perform secondary load test.
First, the structure of the voltage transformer is briefly described, and the voltage transformer comprises an iron core, a primary winding, a secondary winding, terminals and an insulating bracket. The primary winding is connected in parallel with the primary loop of the power system, the secondary winding is connected in parallel with the voltage coil of the measuring instrument, the relay protection device or the automation device, namely when the load is multi-element, the load is connected in parallel with the secondary winding.
As shown in FIG. 2, the voltage transformer parameter experiment and secondary circuit test system comprises a printer, a test host and a display screen, wherein the printer is in communication connection with the test host through a first USB interface, and the display screen is in communication connection with the test host through a second USB interface.
The test host comprises a shell, a plurality of interfaces, a signal acquisition unit, an analog-digital converter, a processor unit and a storage unit, wherein a working indicator lamp and a power input/switch are arranged on the shell, the signal acquisition unit, the analog-digital converter, the processor unit and the storage unit are all arranged in the shell, the interfaces are arranged on the shell and are all in communication connection with the signal acquisition unit, the analog-digital converter and the processor unit are in communication connection in sequence, the processor unit comprises a digital signal processor (Digital Signal Processing, a DSP) and a micro-control unit (Microcontroller Unit, an MCU), the analog-digital converter is in communication connection with the digital signal processor, and a display screen, a man-machine interface (keyboard), a printer and the storage unit are all in communication connection with the micro-control unit.
The signal acquisition unit is used for acquiring analog quantity signals of test points through a plurality of interfaces and sending the analog quantity signals to the analog-digital converter, the analog-digital converter converts the analog quantity signals into digital signals and sends the digital signals to the digital signal processor, the digital signal processor is used for processing the digital signals to produce test results and sending the test results to the micro-control unit, and the micro-control unit is used for carrying out signal level conversion and signal switching according to human-computer interface instructions, so that the tester can be suitable for different test projects; the micro control unit is also used for sending the test result to the display screen for display; the micro control unit is also used for controlling the printer to print the test result according to the instruction of the man-machine interface, and the digital signal processor is also used for sending the test result to the storage unit for storage.
In the embodiment of the utility model, the processor unit is provided with a double CPU structure, the digital signal processor is used for processing a test algorithm, and the micro-control unit is mainly used for man-machine interface, signal conversion and signal switching, so that the test system can be suitable for more working conditions and has high test speed.
For example, the housing is provided with a first interface K1, a second interface K2, a third interface S1, a fourth interface S2, a fifth interface P1, and a sixth interface P2.
As shown in fig. 3, when the transformation ratio and polarity test of the voltage transformer are performed by using the test system, the third interface S1 is connected to the primary side a end of the voltage transformer to be tested, the fourth interface S2 is connected to the primary side X end of the voltage transformer to be tested, the fifth interface P1 is connected to the secondary side a end of the voltage transformer to be tested, and the sixth interface P2 is connected to the secondary side X end of the voltage transformer to be tested.
In the test process, as shown in fig. 4, the transformation ratio and the polarity test item are selected through the human-computer interface, the experimental voltage is input to the secondary winding, the signal acquisition unit acquires the secondary voltage signal through the fifth interface P1 and the sixth interface P2, the signal acquisition unit acquires the primary voltage signal through the third interface S1 and the fourth interface S2, the signal acquisition unit transmits the acquired secondary voltage signal and primary voltage signal to the analog-digital converter, the analog-digital converter converts the secondary voltage signal and primary voltage signal into a first digital signal and a second digital signal respectively, the first digital signal and the second digital signal are transmitted to the digital signal processor, the digital signal processor generates a test result according to the experimental voltage of the secondary winding, the first digital signal and the second digital signal, the test result is transmitted to the display screen for display, the micro-control unit can transmit an instruction to the micro-control unit through the human-computer interface, the micro-control unit can control the printer to print the test result, and the micro-control unit can also transmit the test result to the storage unit through the human-computer interface for storage.
As shown in fig. 5, when the excitation characteristic test of the voltage transformer is performed by using the test system, the third interface S1 is connected to the a end of the secondary side of the voltage transformer to be tested, and the fourth interface S2 is connected to the x end of the secondary side of the voltage transformer to be tested.
As shown in fig. 6, in the test process, an excitation characteristic test item is selected through a human-computer interface, an experimental voltage is input to a secondary winding, a signal acquisition unit acquires a primary current signal through a third interface S1 and a fourth interface S2, the signal acquisition unit transmits the acquired primary current signal to an analog-digital converter, the analog-digital converter converts the primary current signal into a third digital signal and transmits the third digital signal to a digital signal processor, the digital signal processor generates a test result according to the experimental voltage of a secondary winding and the third digital signal, a micro-control unit transmits the test result to a display screen for display, an instruction can be transmitted to the micro-control unit through the human-computer interface, the micro-control unit controls a printer to print the test result, and the micro-control unit can also transmit an instruction to the micro-control unit through the human-computer interface, and the micro-control unit transmits the test result to a storage unit for storage.
As shown in fig. 7, when the secondary circuit line judgment test of the voltage transformer is performed by using the test system, the first interface K1, the second interface K2, the third interface S1 and the fourth interface S2 are respectively connected with the end a, the end B, the end C and the end N of the secondary circuit to be tested in a one-to-one correspondence manner.
In the test process, as shown in fig. 8, a secondary loop line judgment test is selected through a human-computer interface, different voltage values are input to the a phase, the B phase and the C phase of the secondary side winding through an alternating voltage source (0-100V), for example, 30V voltage can be input to the a phase of the secondary side winding, 60V voltage is input to the B phase of the secondary side winding, 80V voltage is input to the C phase of the secondary side winding, the signal acquisition unit acquires voltage signals of the a phase, the B phase and the C phase through a first interface K1, a second interface K2, a third interface S1 and a fourth interface S2, the signal acquisition unit transmits the acquired voltage signals of the a phase, the B phase and the C phase to an analog-digital converter, the analog-digital converter converts the voltage signals of the a phase, the B phase and the C phase to a fourth digital signal, and the digital signal processor generates a test result according to the voltage values input to the a phase, the B phase and the C phase of the secondary loop and the fourth digital signal.
As shown in fig. 9, when the present test system is used to measure the secondary side load of the voltage transformer, the third interface S1 and the fourth interface S2 are connected to both ends of the secondary side load, respectively.
As shown in fig. 10, in the test process, a secondary side load test is selected through a human-computer interface, a set voltage is input to the secondary side load through an ac power supply, a signal acquisition unit acquires a current signal and a voltage signal of the secondary side load through a third interface S1 and a fourth interface S2, the current signal and the voltage signal of the secondary side load are sent to an analog-digital converter, the analog-digital converter converts the current signal and the voltage signal of the secondary side load into a fifth digital signal, the fifth digital signal is sent to a digital signal processor, the digital signal processor generates a test result according to the set voltage input by the secondary side load and the fifth digital signal, the test result is sent to a display screen for display by the digital signal processor, an instruction can be sent to the micro control unit through the human-computer interface, the micro control unit controls a printer to print the test result, and the micro control unit can also send an instruction to the micro control unit through the human-computer interface for storing the test result.
As shown in fig. 11, when the present test system is used to perform a dc resistance test of the secondary winding of the voltage transformer, the first interface K1 and the second interface K2 are connected to two ends of the secondary winding, respectively.
As shown in fig. 12, in the test process, a secondary side load test is selected through a human-computer interface, a set direct current is input to a secondary side winding through a direct current power supply, a signal acquisition unit acquires a direct current voltage signal of the secondary side winding through a first interface K1 and a second interface K2, the direct current voltage signal of the secondary side winding is sent to an analog-digital converter, the analog-digital converter converts the direct current voltage signal of the secondary side winding into a sixth digital signal and sends the sixth digital signal to a digital signal processor, the digital signal processor generates a test result according to the set direct current input by the secondary side winding and the sixth digital signal, the test result is sent to a display screen to be displayed by the digital signal processor, an instruction is sent to the micro control unit through the human-computer interface, the micro control unit controls a printer to print the test result, and the micro control unit can also send an instruction to the micro control unit through the human-computer interface to store the test result.
The voltage transformer parameter experiment and secondary circuit test system provided by the embodiment of the utility model is easy to operate, has complete test functions, and has the function of printing test reports. The test system has the advantages of simple hardware structure, high intelligent degree, high integration level, high verification speed, simple and convenient operation, and can be widely applied to the voltage transformer test of substations of various grades.
The test system of the utility model can perform voltage transformer characteristic tests of 220, 110, 35 and 10 kilovolts or below, and is a multifunctional test system, and has the functions of excitation characteristic (volt-ampere characteristic) measurement, automatic inflection point value giving, transformation ratio measurement, polarity judgment, secondary winding resistance measurement, secondary load measurement, angle difference measurement, line judgment, iron core demagnetization and the like. The utility model adopts differential pressure virtual load measurement to the secondary circuit of the voltage transformer, and the instrument can also achieve the purpose of checking the correct wiring of the secondary circuit of the voltage transformer.
The test system fully considers the requirements of the test precision, stability, reliability and anti-interference capability, and provides reliable guarantee for the whole equipment in the test process. The test system provided by the utility model is convenient to use, high in safety, high in intelligent degree, high in verification speed and high in anti-interference capability, and meanwhile, the working time of the test is greatly shortened, and the working efficiency is improved.
Although the utility model has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present utility model.
Claims (10)
1. The voltage transformer parameter experiment and secondary circuit test system is characterized by comprising a test host, wherein the test host comprises a plurality of interfaces, a signal acquisition unit, an analog-digital converter and a processor unit;
the signal acquisition unit is in communication connection with the interfaces, and the signal acquisition unit, the analog-digital converter and the processor unit are in communication connection in sequence.
2. The system according to claim 1, wherein the test host further comprises a housing, the signal acquisition unit, the analog-to-digital converter and the processor unit are all disposed in the housing, and a plurality of interfaces are disposed on the housing, and the plurality of interfaces include a first interface K1, a second interface K2, a third interface S1, a fourth interface S2, a fifth interface P1 and a sixth interface P2.
3. The system for testing parameters of a voltage transformer and a secondary circuit according to claim 2, wherein when the transformation ratio and polarity of the voltage transformer are tested, the third interface S1 is connected with the primary side a end of the voltage transformer to be tested, the fourth interface S2 is connected with the primary side X end of the voltage transformer to be tested, the fifth interface P1 is connected with the secondary side a end of the voltage transformer to be tested, and the sixth interface P2 is connected with the secondary side X end of the voltage transformer to be tested.
4. The system for testing parameters of a voltage transformer and a secondary circuit according to claim 2, wherein the third interface S1 is connected to the secondary side a of the voltage transformer to be tested, and the fourth interface S2 is connected to the secondary side x of the voltage transformer to be tested when testing the excitation characteristics of the voltage transformer.
5. The system for testing parameters of a voltage transformer and a secondary circuit according to claim 2, wherein the first interface K1, the second interface K2, the third interface S1 and the fourth interface S2 are respectively connected with the a end, the B end, the C end and the N end of the secondary circuit to be tested in a one-to-one correspondence manner during the secondary circuit line judgment test of the voltage transformer.
6. The system for testing parameters of a voltage transformer and a secondary circuit according to claim 2, wherein the third interface S1 and the fourth interface S2 are respectively connected to two ends of a secondary load when the secondary load of the voltage transformer is measured.
7. The system for testing parameters of a voltage transformer and a secondary circuit according to claim 2, wherein the first interface K1 and the second interface K2 are respectively connected with two ends of the secondary winding when the direct current resistance of the secondary winding of the voltage transformer is tested.
8. The system for testing parameters of voltage transformers and secondary loops according to any of claims 1-7, further comprising a printer and a display, both in communication with the test host.
9. The system of claim 8, wherein the processor unit comprises a digital signal processor and a micro control unit, the analog-to-digital converter is communicatively connected to the digital signal processor, and the display screen and the printer are communicatively connected to the micro control unit.
10. The system of claim 9, wherein the test host further comprises a memory unit, and wherein the memory unit is communicatively connected to the digital signal processor and the micro-control unit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321509160.XU CN220709338U (en) | 2023-06-13 | 2023-06-13 | Voltage transformer parameter experiment and secondary circuit test system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321509160.XU CN220709338U (en) | 2023-06-13 | 2023-06-13 | Voltage transformer parameter experiment and secondary circuit test system |
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| CN220709338U true CN220709338U (en) | 2024-04-02 |
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| CN202321509160.XU Active CN220709338U (en) | 2023-06-13 | 2023-06-13 | Voltage transformer parameter experiment and secondary circuit test system |
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2023
- 2023-06-13 CN CN202321509160.XU patent/CN220709338U/en active Active
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