CN213302497U - Current transformer secondary side loop detection device and circuit - Google Patents
Current transformer secondary side loop detection device and circuit Download PDFInfo
- Publication number
- CN213302497U CN213302497U CN202021922639.2U CN202021922639U CN213302497U CN 213302497 U CN213302497 U CN 213302497U CN 202021922639 U CN202021922639 U CN 202021922639U CN 213302497 U CN213302497 U CN 213302497U
- Authority
- CN
- China
- Prior art keywords
- voltmeter
- voltage regulator
- terminal
- oscilloscope
- secondary side
- 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.)
- Expired - Fee Related
Links
Images
Abstract
The utility model discloses a current transformer secondary side loop detection device and circuit, which comprises a detection box and an upper cover, wherein the detection box is connected with the upper cover through a hinge, and the detection box and the front side of the upper cover are fixed through a pressing lock catch; the detection box is provided with a power supply jack, a grounding terminal, an S1 terminal, an S2 terminal, a P1 terminal, a P2 terminal, an oscilloscope, a voltage regulator, a first voltmeter, a second voltmeter and a protection air switch; the device can synchronously detect the transformation ratio and the polarity of the secondary side current loop of the current transformer, shortens the detection time and improves the working efficiency.
Description
Technical Field
The utility model relates to a current transformer secondary circuit detects technical field, concretely relates to current transformer secondary side return circuit detection device and circuit.
Background
Before starting power transmission, the accuracy of a secondary circuit needs to be checked in capital construction and technical improvement projects. In recent years, the power supply load is continuously increased, a plurality of transformer substations are newly built every year, the checking and accepting work in the transformer substations is relatively heavy, and the secondary checking and accepting work is completely finished by relay protection specialties. The checking and accepting work of the secondary system is mainly divided into protection device debugging, secondary loop inspection and relay protection countermeasure investigation. The secondary circuit is a link connecting primary equipment and secondary equipment such as relay protection, a metering device, a safety automatic device, a fault recording device and the like, and the correctness of the secondary circuit is a key for ensuring the safe and stable operation of a primary system of a transformer substation; secondly, the secondary circuit is distributed at each corner of the transformer substation, and the aspects of equipment monitoring, measurement, control, protection, regulation and the like are involved, so that a great deal of time and energy are consumed in each secondary circuit acceptance.
The inspection work of the secondary circuit can be classified into the following four categories: voltage loop inspection, current loop inspection, control loop inspection and signal loop inspection; the inspection of the current loop accounts for a large proportion of the inspection of the whole secondary loop, and the main symptom causing the long inspection time of the secondary loop is the long time consumption of the inspection of the current loop, wherein the current loop mainly comprises protection, measurement, metering, failure recording, mother difference, electric energy quality and the like according to different purposes, and the detection of the aspects of transformation ratio, polarity, accuracy level, volt-ampere characteristics and the like is mainly carried out.
The traditional method for detecting the transformation ratio is to use a large current generator to introduce large current (voltage is applied to the device) to the primary side of the CT, and check the magnitude of the current in each loop of the secondary side, thereby determining the transformation ratio of the loop; the traditional polarity measuring method is a method using dry batteries for 'point polarity', the working principle is that the dry batteries are added at two ends of the primary side of a CT (computed tomography) to enable the dry batteries to flow tiny direct current, a pointer type milliammeter is connected to the secondary side, and the polarity adding or the polarity reducing is determined by observing whether the deflection direction of a pointer is a positive direction or a negative direction; the traditional method needs separate tests for measuring the transformation ratio and polarity of a current loop; not only wasting manpower but also wasting a lot of time; based on the technical background, the inventor designs a device and a circuit for detecting a secondary side loop of a current transformer, and the device can synchronously detect the transformation ratio and the polarity of the secondary side current loop of the current transformer, shorten the detection time and improve the working efficiency.
Disclosure of Invention
An object of the utility model is to provide a current transformer secondary side return circuit detection device and circuit, this device can carry out synchronous the detecting to the transformation ratio, the polarity in current transformer secondary side current loop, shortens check-out time, promotes work efficiency.
The utility model adopts the technical scheme as follows: a secondary side loop detection device of a current transformer comprises a detection box and an upper cover, wherein the detection box is connected with the upper cover through a hinge, the detection box is fixed with the front side of the upper cover through a pressing lock catch, and a power jack, a grounding terminal, an S1 terminal, an S2 terminal, a P1 terminal, a P2 terminal, an oscilloscope, a voltage regulator, a first voltmeter, a second voltmeter and a protection air switch are arranged on the detection box; the power jack is electrically connected with the oscilloscope, the voltage regulator, the first voltmeter and the second voltmeter; the grounding binding post is electrically connected with the oscilloscope, the voltage regulator, the voltmeter I and the voltmeter II; the voltage regulator is electrically connected with the first voltmeter and the second voltmeter; the S1 wiring terminal and the S2 wiring terminal are electrically connected with the voltage regulator through wires, and the P1 wiring terminal and the P2 wiring terminal are electrically connected with the second voltmeter through wires; the probe of the oscilloscope channel I is connected with the voltage regulator and is used for detecting the waveform of the secondary side voltage of the CT; and a probe of the oscilloscope channel II is connected with the voltmeter II, detects the waveform of the primary side voltage of the CT, and protects the air switch from being connected with an output loop of the voltage regulator.
Specifically, the voltage regulator is a TDGC2J-2 type alternating current voltage regulator; the first voltmeter and the second voltmeter are HB404 type digital display voltmeters; the oscilloscope is a Hantek2C42 type oscilloscope.
Further, a handle is arranged on the front side of the detection box.
The beneficial effects of the utility model reside in that: the device can synchronously detect the transformation ratio and the polarity of the secondary side current loop of the current transformer, shortens the detection time and improves the working efficiency.
In addition, the invention also has the following characteristics:
1. connecting the tail end P2 of a primary winding of the CT and the tail end S2 of a secondary winding of the CT to ground, wherein the number of turns of the secondary winding of the current transformer is more than that of the primary winding, so that the CT is seen from the secondary side to form a step-down transformer, an alternating voltage U1 is added between the two ends S1 and S2 of the secondary winding with more turns by using a voltage regulator, the added voltage signal is transmitted to the primary side of the CT according to the transformation ratio of the CT, and the transformation ratio of the CT can be calculated by measuring the voltages at the two sides of the CT through a voltmeter;
2. for the judgment of CT polarity, a dry battery is used for adding a direct current signal to CT, and the device adds an alternating current signal to CT through a voltage regulator, so that the waveforms of voltage signals on two sides of CT can be clearly observed through an oscilloscope, and if the wiring on two sides is connected to the same-name end, the observed waveforms are in the same phase; if the wiring at the two sides is connected with the different name end, the observed waveform is in an opposite phase, so that the correctness of the CT polarity can be judged;
3. in this application, for protection AC voltage regulator not overload generates heat, install the empty division of protection of a 1A additional in output circuit, when the electric current exceeded 1A, the empty division of protection was disconnected in the twinkling of an eye to avoid AC voltage regulation to damage.
Drawings
Fig. 1 is a schematic perspective view of the present invention.
Fig. 2 is a schematic view of the handle position of the present invention.
Fig. 3 is a schematic view of the hinge position of the present invention.
FIG. 4 is a schematic diagram of a circuit detection connection.
FIG. 5 is a schematic diagram of a judgment waveform.
Fig. 6 is a circuit connection diagram.
In the figure: the device comprises a detection box 1, an upper cover 2, a hinge 3, a press lock catch 4, a power jack 5, a grounding binding post 6, an S1 binding post 7, an S2 binding post 8, a P1 binding post 9, a P2 binding post 10, an oscilloscope 11, a voltage regulator 12, a voltmeter I13, a voltmeter II 14, a protection air switch 15 and a handle 16.
Detailed Description
In order to make the technical solutions of the present invention better understood by those skilled in the art, the present invention will be further described in detail with reference to the accompanying drawings, which are only used for illustrating the technical solutions of the present invention and are not limited.
In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; the two components can be directly connected or indirectly connected through an intermediate medium, and the two components can be communicated with each other; the specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.
The present invention will be further described in detail with reference to fig. 1 to 6, and a schematic structure of a secondary side loop detection device and a circuit for a current transformer is as follows.
The device comprises a detection box 1 and an upper cover 2, wherein the detection box 1 is connected with the upper cover 2 through a hinge 3, the detection box 1 is fixed with the front side of the upper cover 2 through a pressing lock catch 4, and the upper cover 2 is opened and closed through the pressing lock catch 4; a handle 16 is arranged on the front side of the detection box 1, so that the device is convenient to carry; the detection box 1 is provided with a power supply jack 5, a grounding terminal 6, an S1 terminal 7, an S2 terminal 8, a P1 terminal 9, a P2 terminal 10, an oscilloscope 11, a voltage regulator 12, a first voltmeter 13, a second voltmeter 14 and a protection switch 15; the power jack 5 is electrically connected with the oscilloscope 11, the voltage regulator 12, the first voltmeter 13 and the second voltmeter 14, and an external power supply supplies power to the device through the power jack 5; the oscilloscope 11, the voltage regulator 12, the first voltmeter 13 and the second voltmeter 14 are grounded through the grounding terminal 6; the voltage regulator 12 is electrically connected with the first voltmeter 13 and the second voltmeter 14; the S1 terminal 7 and the S2 terminal 8 are electrically connected with the voltage regulator 12 through leads, and the P1 terminal 9 and the P2 terminal 10 are electrically connected with the second voltmeter 14 through leads; a probe of a first channel of the oscilloscope 11 is connected with the voltage regulator 12 and is used for detecting the waveform of the secondary side voltage of the CT; a probe of a channel II of the oscilloscope 11 is connected with a secondary voltage 14 meter and is used for detecting the waveform of the primary side voltage of the CT; in order to protect the alternating current voltage regulator from overload and heating, a 1A protection air switch 15 is additionally arranged in an output loop of the voltage regulator 12, and when the current exceeds 1A, the protection air switch 15 is instantly disconnected, so that the alternating current voltage regulation damage is avoided.
The voltage regulator adopts a TDGC2J-2 type alternating current voltage regulator, and the input voltage of 220V and the output voltage of 0-250V can be adjusted arbitrarily; the first voltmeter and the second voltmeter are HB404 type digital display voltmeters, the voltmeter has an alternating current and direct current voltage display function, the measurement range is 0-500V, and both the measuring range and the display precision can be set; the oscilloscope is a Hantek2C42 type oscilloscope; the device has a dual-channel display function, the range of detectable voltage signals is plus or minus 800V, and the two channels sample simultaneously.
The traditional method for detecting the transformation ratio is to use a large current generator to introduce large current (voltage is applied to the device) to the primary side of the CT, and check the magnitude of the current in each loop of the secondary side, thereby determining the transformation ratio of the loop; however, this approach is dangerous: if the secondary circuit has a break point or an open circuit in the process of rising current, high overvoltage is generated on the secondary side to hurt personnel and equipment; in addition, the loss of the iron core is increased, the possibility of burning insulation is caused by serious heating, and the error of the mutual inductor is increased due to residual magnetism generated in the iron core, so that the metering accuracy is influenced; in the application, the tail end P2 of a primary winding of the CT and the tail end S2 of the secondary winding are connected together and grounded, an alternating voltage U1 is connected between the two ends S1 and S2 of the secondary winding with more turns by using a voltage regulator 12, the number of turns of the secondary winding of the current transformer is more than that of the primary winding, the CT looks into a step-down transformer from the secondary side, an added voltage signal is transmitted to the primary side of the CT according to the transformation ratio of the CT, the transformation ratio of the CT can be calculated by measuring the voltages at the two sides of the CT through a primary voltmeter 13 and a secondary voltmeter 14, and the safety of the added voltage is higher than that of a traditional method for.
The traditional polarity measuring method is a method using dry batteries for 'point polarity', the working principle is that a plurality of dry batteries are added at two ends of the primary side of a CT (computed tomography) to enable the CT to flow tiny direct current, a pointer type milliammeter is connected to the secondary side, and the polarity adding or polarity reducing is determined by observing whether the deflection direction of a pointer is a positive direction or a negative direction; in the application, the voltage is applied to the CT through the voltage regulator 12, so that the waveforms of voltage signals on two sides of the CT can be clearly observed through an oscilloscope, and if the connection wires on two sides are connected to the same-name end, the observed waveforms are in the same phase; if the two side connection wires are connected to the different name end, the observed wave form is the reverse phase, so that the correctness of the CT polarity can be judged.
In the first embodiment, the main transformer interval of a certain transformer substation is checked, wherein the transformation ratio of a neutral point bushing CT of the main transformer is 300/1; the S1 terminal 7 and the S2 terminal 8 of the device are respectively connected to the S1 end and the S2 end of the secondary winding of the transformer 0 phase (neutral point) bushing CT; the P1 binding post 9 and the P2 binding post 10 of the device are respectively connected to the end part of a primary side binding post of a bushing CT of a transformer 0 phase (neutral point) and a C phase (any phase); when a voltage of 30V is applied to the secondary winding, the voltage detected at the primary side is 0.1V, and the transformation ratio of the CT is 300/1, so that the transformation ratio is correct; meanwhile, the phases of the voltage waveforms on the two sides of the CT are the same, which shows that the two sides of the CT are wired according to the polarity reduction principle, and the polarity is correct.
Although the present invention has been described in detail with reference to the foregoing examples, it will be apparent to those skilled in the art that various changes and modifications can be made in the embodiments described above, or equivalent changes and modifications can be made to some of the technical features of the embodiments described above, and any changes, equivalents, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of the present invention.
Claims (5)
1. The utility model provides a current transformer secondary side return circuit detection device, includes detection box, upper cover, detects the box and passes through hinge connection with the upper cover, and it is fixed its characterized in that through pressing the hasp to detect the front side of box and upper cover: the detection box is provided with a power supply jack, a grounding terminal, an S1 terminal, an S2 terminal, a P1 terminal, a P2 terminal, an oscilloscope, a voltage regulator, a first voltmeter, a second voltmeter and a protection air switch; the power jack is electrically connected with the oscilloscope, the voltage regulator, the first voltmeter and the second voltmeter; the grounding binding post is electrically connected with the oscilloscope, the voltage regulator, the voltmeter I and the voltmeter II; the voltage regulator is electrically connected with the first voltmeter and the second voltmeter; the S1 wiring terminal and the S2 wiring terminal are electrically connected with the voltage regulator through wires, and the P1 wiring terminal and the P2 wiring terminal are electrically connected with the second voltmeter through wires; the probe of the oscilloscope channel I is connected with the voltage regulator and is used for detecting the waveform of the secondary side voltage of the CT; and the probe of the oscilloscope channel II is connected with the voltmeter II to detect the waveform of the primary side voltage of the CT, and the protection air switch is connected in an output loop of the voltage regulator.
2. The device for detecting the secondary side loop of the current transformer as claimed in claim 1, wherein: the voltage regulator is a TDGC2J-2 type alternating current voltage regulator; the first voltmeter and the second voltmeter are HB404 type digital display voltmeters; the oscilloscope is a Hantek2C42 type oscilloscope.
3. The secondary side loop detection device of a current transformer according to any one of claims 1-2, wherein: the front side of the detection box is provided with a handle.
4. A circuit for detecting accuracy of a secondary side loop of a current transformer is characterized in that: the voltage regulator is electrically connected with the first voltmeter and the second voltmeter; the probe of the oscilloscope channel I is connected with the voltage regulator and is used for detecting the waveform of the secondary side voltage of the CT; and the probe of the oscilloscope channel II is connected with the voltmeter II to detect the waveform of the primary side voltage of the CT.
5. The accuracy detection circuit for the secondary side loop of the current transformer as claimed in claim 4, wherein: and a protection air switch is connected in an output loop of the voltage regulator.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021922639.2U CN213302497U (en) | 2020-09-07 | 2020-09-07 | Current transformer secondary side loop detection device and circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021922639.2U CN213302497U (en) | 2020-09-07 | 2020-09-07 | Current transformer secondary side loop detection device and circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN213302497U true CN213302497U (en) | 2021-05-28 |
Family
ID=76029150
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202021922639.2U Expired - Fee Related CN213302497U (en) | 2020-09-07 | 2020-09-07 | Current transformer secondary side loop detection device and circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN213302497U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112582161A (en) * | 2020-11-20 | 2021-03-30 | 许继（厦门）智能电力设备股份有限公司 | Quick grounding device of current transformer |
-
2020
- 2020-09-07 CN CN202021922639.2U patent/CN213302497U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112582161A (en) * | 2020-11-20 | 2021-03-30 | 许继（厦门）智能电力设备股份有限公司 | Quick grounding device of current transformer |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102680798B (en) | Online measurement method and device for grounding resistor of rod tower | |
| CN205080251U (en) | Through -flow calibration system of current transformer secondary circuit | |
| CN101271129B (en) | Sensor type high tension electricity energy gauging method | |
| CN202854255U (en) | Capacitor type potential transformer testing device | |
| CN203838286U (en) | Current transformer polarity tester | |
| CN109884439B (en) | Black-start test system and method for power system | |
| CN203502540U (en) | Current transformer polarity tester | |
| CN103454544B (en) | A kind of detection method based on the linear magnetism elimination circuit of electronic jumper | |
| CN103308807A (en) | Transformer state detection device and breaker | |
| CN103777077B (en) | Wireless pincerlike phase detection device | |
| CN101614798B (en) | Polarity detection system of electronic transformer | |
| CN112363090A (en) | Metering secondary circuit wiring test method | |
| CN213302497U (en) | Current transformer secondary side loop detection device and circuit | |
| CN109283421B (en) | Low-voltage power-on detection test method and device for railway traction substation | |
| CN109406907A (en) | High-impedance transformer simulates on-load through-flow test device and test method | |
| CN210427707U (en) | Integrated insulation detection's on-vehicle machine test system that charges | |
| CN104034977A (en) | Capacitive voltage transformer electrified detector | |
| CN113325355A (en) | Portable on-site three-phase mutual inductor wiring judgment device | |
| CN203772958U (en) | Wireless clamp-shaped phase detection device | |
| CN203259488U (en) | Measuring system for thermal contact resistance of parallel groove clamp | |
| CN108152659B (en) | Method for judging turn-to-turn insulation short circuit of electromagnetic voltage transformer | |
| CN112505543A (en) | Large-scale generator iron loss detection system and method | |
| CN201464596U (en) | Electronic transducer polarity detecting system | |
| CN111537797A (en) | System and method for measuring insulation resistance of transformer substation without disassembling lead | |
| CN215219111U (en) | Online real-time monitoring and warning device of voltage transformer multipoint earthing |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20210528 Termination date: 20210907 |