CN216144940U - System and equipment for live-line checking of current transformer - Google Patents
System and equipment for live-line checking of current transformer Download PDFInfo
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- CN216144940U CN216144940U CN202122001833.8U CN202122001833U CN216144940U CN 216144940 U CN216144940 U CN 216144940U CN 202122001833 U CN202122001833 U CN 202122001833U CN 216144940 U CN216144940 U CN 216144940U
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Abstract
The utility model discloses a system and equipment for live-line checking of a current transformer, which relate to the technical field of checking of the current transformer, wherein the system comprises a current transformer to be tested CTx, a standard current transformer CT1, a standard current transformer CT2 and a comprehensive processing device; the standard current transformer CT1 is connected in series on a primary winding loop of the current transformer CTx to be detected and is used for detecting primary current I1 on the primary winding loop; the standard current transformer CT2 is connected in series on a secondary winding loop of the current transformer CTx to be detected and is used for detecting the secondary current Ix on the secondary winding loop; and the standard current transformer CT1 and the standard current transformer CT2 are both connected with a comprehensive processing device, and the comprehensive processing device is used for calculating the error of the current transformer to be detected CTx according to the detected primary current I1 and secondary current Ix. The online electrified calibration system can rapidly realize online electrified calibration of the error of the current transformer on the premise of no power failure, and is smaller in size and portable in use.
Description
Technical Field
The utility model relates to the technical field of current transformer calibration, in particular to a system and equipment for live calibration of a current transformer.
Background
The current transformer is used as an important component of an electric energy metering device, is mainly used for providing current signals with accurate proportion relation with a primary loop in electric measurement, electric energy metering and automation devices, and plays a key role in terminal electric energy metering. After the current transformer is installed in a circuit, power failure detection needs to be carried out regularly or at fixed points, and if errors exceed the limit or measurement is inaccurate in the using process of the current transformer, the situation is difficult to find in time, so that measurement of terminal electric energy measurement is inaccurate.
If the circuit is not powered off, the related technology discloses a system and a method for calibrating a low-voltage current transformer without power failure, which belong to the technical field of low-voltage current transformers. Although the related technology can carry out error detection on the low-voltage current transformer according to the detection regulation requirement under the condition that a low-voltage line is not powered off, the problem that the current low-voltage current transformer cannot accurately measure under the condition that the line is not powered off is solved.
However, the above-mentioned related art uses the flow-through assay, and further requires the use of a current booster or the like to generate a conditioning current in accordance with the test requirements, and requires a large space for installing the apparatus for assay.
SUMMERY OF THE UTILITY MODEL
The utility model provides a system and equipment for checking a current transformer with power supply, aiming at solving the defects that the current transformer has large volume, heavy weight and potential safety hazard in the uninterrupted checking equipment.
The technical scheme adopted by the utility model is as follows:
the system for electrified checking of the current transformer comprises a current transformer to be tested CTx, a standard current transformer CT1, a standard current transformer CT2 and a comprehensive processing device; the current transformer CTx to be tested comprises a primary winding and a secondary winding; the standard current transformer CT1 is connected in series on a primary winding loop of the current transformer to be tested CTx, and the standard current transformer CT2 is connected in series on a secondary winding loop of the current transformer to be tested CTx; and the standard current transformer CT1 and the standard current transformer CT2 are both connected with a comprehensive processing device.
Further, the standard current transformer CT1 and the standard current transformer CT2 are both pincer-shaped standard current transformers.
Further, the standard current transformer CT1 is clamped on a primary winding loop of the current transformer CTx to be tested; the standard current transformer CT2 is clamped on a secondary winding loop of the current transformer CTx to be tested.
Further, the primary current range of the standard current transformer CT1 is greater than or equal to the primary current range of the current transformer CTx to be tested.
Furthermore, the comprehensive processing device comprises a signal converter and a check tester, the signal converter and the check tester are integrated into a whole or are arranged independently, and the signal converter is electrically connected with the check tester.
Further, the checking tester comprises a processor, a data transmission module and a man-machine interaction screen; the processor is respectively in communication connection with the data transmission module, the man-machine interaction screen and the signal converter.
Further, the checking tester also comprises a power supply module; the power supply module is respectively connected with the processor, the data transmission module and the human-computer interaction screen and used for providing power.
Further, the signal converter is connected with the processor through two signal channels.
In a first aspect, an apparatus for live-line verification of a current transformer is provided, and includes a standard current transformer CT1, a standard current transformer CT2 and an integrated processing device; the standard current transformer CT1 is connected in series on a primary winding loop of the current transformer to be tested CTx, and the standard current transformer CT2 is connected in series on a secondary winding loop of the current transformer to be tested CTx; and the standard current transformer CT1 and the standard current transformer CT2 are both connected with a comprehensive processing device.
Further, the standard current transformer CT1 and the standard current transformer CT2 are both pincer-shaped standard current transformers; the standard current transformer CT1 is clamped on a primary winding loop of a current transformer CTx to be tested; the standard current transformer CT2 is clamped on a secondary winding loop of the current transformer CTx to be tested.
The utility model has the beneficial effects that:
the beneficial effect of this application includes: on the premise of no power failure, the online live measurement of the error of the current transformer is realized quickly, and the volume is smaller and is easier to carry.
The embodiment of the application provides a system and equipment for live-line checking of a current transformer, wherein a standard current transformer CT1 is used for detecting a primary current I1 on a primary winding loop of a current transformer CTx to be detected, a secondary current Ix on a secondary winding loop of the current transformer CTx to be detected is detected through a standard current transformer CT2, and a comprehensive processing device can be used for simply calculating and analyzing the primary current I1 and the secondary current Ix so as to quickly obtain the error of the current transformer CTx to be detected; meanwhile, in the verification and calibration process of the system, the states of the current transformer CTx to be tested and the circuit thereof cannot be changed or influenced, and electric quantity loss cannot be caused. Therefore, the method and the device solve the problem that the power failure verification time of the power grid and the user cannot be coordinated, reduce the composition of the system, and realize the accuracy verification of the online error of the current transformer CTx to be detected without 'injection'.
Drawings
Fig. 1 is a circuit connection diagram of a standard current transformer CT1, a standard current transformer CT2 and a current transformer CTx to be tested in a system with a current transformer for verification by electrification according to an embodiment of the present disclosure;
fig. 2 is a block diagram of a comprehensive processing device in a system for live-line verification of a current transformer according to an embodiment of the present disclosure;
fig. 3 is a schematic composition diagram of an apparatus for electrically verifying a current transformer according to an embodiment of the present application.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
The flow diagrams depicted in the figures are merely illustrative and do not necessarily include all of the elements and operations/steps, nor do they necessarily have to be performed in the order depicted. For example, some operations/steps may be decomposed, combined or partially combined, so that the actual execution sequence may be changed according to the actual situation.
The embodiment of the application provides a system for checking a current transformer with electricity, which solves the problem that the time for power failure detection of a power grid and a user cannot be coordinated, reduces the composition of the system, reduces the weight so as to be convenient to carry, can realize the precision check of the online error of the current transformer (CTx) to be detected without 'flow injection', and also reduces the volume of the system for checking the current transformer with electricity. In short, the embodiment of the application can quickly realize the online measurement of the error of the current transformer on the premise of not power failure, and has smaller volume and more portability in use.
Some embodiments of the present application will be described in detail below with reference to the accompanying drawings. The embodiments described below and the features of the embodiments can be combined with each other without conflict.
As shown in fig. 1, an embodiment of the present application provides a system for live-line verification of a current transformer, which includes a current transformer to be tested CTx, a standard current transformer CT1, a standard current transformer CT2, and a comprehensive processing device.
The current transformer CTx to be tested comprises a primary winding and a secondary winding.
The standard current transformer CT1 is connected in series on a primary winding loop of the current transformer CTx to be tested; the standard current transformer CT1 is used for detecting a primary current I1 on a primary winding loop of the current transformer CTx to be detected.
The standard current transformer CT2 is connected in series on a secondary winding loop of the current transformer CTx to be tested; the standard current transformer CT2 is used for detecting the secondary current Ix on the secondary winding loop of the current transformer CTx to be detected.
And the standard current transformer CT1 and the standard current transformer CT2 are both connected with a comprehensive processing device. And the comprehensive processing device is used for calculating the error of the current transformer CTx to be measured according to the detected primary current I1 and the detected secondary current Ix.
In the embodiment of the application, the current transformer CTx to be tested comprises a primary winding and a secondary winding; the standard current transformer CT1 is connected in series with a primary winding of a current transformer CTx to be detected, an impedance type line load Z is arranged on the primary winding, the standard current transformer CT2 is connected in series with a secondary winding of the current transformer CTx to be detected, so that the standard current transformer CT1 and the standard current transformer CT2 can simultaneously detect a primary current I1 and a secondary current Ix on a line where the current transformer CTx to be detected is located, the detected primary current I1 and the detected secondary current Ix are directly used as input parameters to be connected into a comprehensive processing device, calculation and analysis can be simply carried out, and further the error of the current transformer CTx to be detected is quickly obtained; meanwhile, in the verification process of the system, the states of the current transformer CTx to be detected and the circuit where the current transformer CTx is located cannot be changed or influenced, and electric quantity loss cannot be caused.
Therefore, the problem that the power failure verification time of a power grid and a user cannot be coordinated is solved, the system composition is reduced, the weight is reduced so as to be convenient to carry, online error precision verification of the current transformer CTx to be detected can be realized without 'injection', and the volume of the system for verifying the current transformer in a charged mode is also reduced.
Further, the standard current transformer CT1 and the standard current transformer CT2 are both pincer-shaped standard current transformers; the standard current transformer CT1 is clamped on a primary winding loop of a current transformer CTx to be tested; the standard current transformer CT2 is clamped on a secondary winding loop of the current transformer CTx to be tested.
In this embodiment of the application, the standard pincerlike current transformers all use standard current transformers whose accuracy meets expectations, the standard current transformer CT1 is clamped on a primary winding of the current transformer to be tested CTx, detects a primary current I1 on a line where the current transformer to be tested CTx is located, and sends the primary current I1 to the integrated processing device, and the standard current transformer CT2 is clamped on a secondary winding of the current transformer to be tested CTx, detects a secondary current Ix on the line where the current transformer to be tested CTx is located, and sends the secondary current Ix to the integrated processing device.
Necessarily, the primary current range of the standard current transformer CT1 is greater than or equal to the primary current range of the current transformer CTx to be tested. In order to ensure the safety and reliability of the standard current transformer CT1, the primary current range is not lower than that of the current transformer CTx to be tested, and the standard current transformer CT1 is prevented from being burnt out due to overcurrent of current on a line.
Specifically, the transformation ratio of the standard current transformer CT1 is 1000A/100mA, and the transformation ratio of the standard current transformer CT2 is 10A/4 mA. In the embodiment of the application, if the primary current range of the current transformer CTx to be tested is 1000A, the current range on the secondary winding of the current transformer CTx to be tested is 5A, that is, the secondary current range is 5A, the transformation ratio of the standard current transformer CT1 is 1000A/100mA, the transformation ratio of the standard current transformer CT2 is 10A/4mA, and the requirement can be met, and meanwhile, in order to ensure the accuracy of the verification result of the whole system with the current transformer to be verified, the accuracy level of the whole system is required to be at least 0.05 level.
As shown in fig. 2, as a preferable solution in the embodiment of the present application, the comprehensive processing apparatus includes a signal converter and a verification tester, where the signal converter is integrated on the verification tester to form an integrated device, or the signal converter and the verification tester are separately disposed and electrically connected.
In the embodiment of the application, the verification tester does not directly use the current signal, so before the input parameters are input to the verification tester for mathematical operation, a signal converter is also used for converting the current signal into a signal, such as a voltage signal, which can be received by the verification tester.
Furthermore, the checking tester comprises a processor, a data transmission module and a human-computer interaction screen, wherein the processor is in communication connection with the signal converter, the data transmission module and the human-computer interaction screen.
Furthermore, the checking tester also comprises a power supply module; the power supply module is respectively connected with the processor, the data transmission module and the human-computer interaction screen and used for providing power.
In order to ensure the accuracy of data transmission, the signal converter is connected with the processor through two signal channels.
In the embodiment of the application, the signal converter receives the detected primary current I1 and the detected secondary current Ix, and converts the primary current I1 and the secondary current Ix into corresponding voltage signals respectively, the two voltage signals are not interfered with each other, the two voltage signals are connected with the processor through a signal channel, after the processor obtains the two voltage signals, the amplitude and the phase corresponding to the two voltage signals are obtained according to an FFT algorithm, the error of the amplitude and the phase of the two voltage signals is obtained according to an error measurement algorithm, the error is compared with the error limit value of the current transformer to be detected CTx, whether the error of the current transformer to be detected CTx meets the requirement can be judged, the judgment result is displayed through a human-computer interaction screen, and the judgment result can also be sent to an external device through a wireless or wired mode through a data transmission module.
Meanwhile, the calibration tester is also provided with a power supply module, so that a power supply does not need to be searched on site, and the problem that the determinacy of the calibration result is deviated due to uneven quality of the site power supply is avoided.
It should be noted that, after receiving the input parameters, the integrated processing device in the embodiment of the present application, the primary current I1 and the secondary current Ix may perform an automatic mathematical operation quickly, where a specific mathematical operation process is simple and convenient, and is not the point of the embodiment of the present application, and is not described in detail herein.
In the embodiment of the application, the system is based on load current on a line, under the condition of no power failure, the standard current transformer CT1 and the standard current transformer CT2 are used for detecting the primary current I1 and the secondary current Ix on the line where the current transformer CTx to be detected is located, and the primary current I1 and the secondary current Ix are used as input parameters to perform automatic mathematical operation to obtain the corresponding error of the current transformer CTx to be detected, so that the error precision requirement of the current transformer for live verification can be met, no extra 'injection' is needed in the verification process, the system is more efficient and safe, fewer in composition and smaller in size, convenient to carry and transport, and good in commercial application prospect.
As shown in fig. 3, an embodiment of the present application further provides an apparatus for live-line calibration of a current transformer, which includes a standard current transformer CT1, a standard current transformer CT2, and an integrated processing device.
The standard current transformer CT1 is connected in series on a primary winding loop of the current transformer CTx to be tested; the standard current transformer CT1 is used for detecting a primary current I1 on a primary winding loop of the current transformer CTx to be detected.
The standard current transformer CT2 is connected in series on a secondary winding loop of the current transformer CTx to be tested; the standard current transformer CT2 is used for detecting the secondary current Ix on the secondary winding loop of the current transformer CTx to be detected.
And the standard current transformer CT1 and the standard current transformer CT2 are both connected with a comprehensive processing device. And the comprehensive processing device is used for calculating the error of the current transformer CTx to be measured according to the detected primary current I1 and the detected secondary current Ix.
In the embodiment of the application, the standard current transformer CT1 is used to be connected in series with the primary winding of the current transformer to be tested CTx, the standard current transformer CT2 is used to be connected in series with the secondary winding of the current transformer to be tested CTx, so that the standard current transformer CT1 and the standard current transformer CT2 can simultaneously detect the primary current I1 and the secondary current Ix on the line where the current transformer to be tested CTx is located, and the detected primary current I1 and the detected secondary current Ix are directly used as input parameters to be connected to the comprehensive processing device, so that simple calculation and analysis can be performed, and the error of the current transformer to be tested CTx can be obtained quickly; meanwhile, in the process that the equipment is connected into the line or in the verification process by using the equipment, the states of the current transformer CTx to be tested and the line where the current transformer CTx is located cannot be changed or influenced, and electric quantity loss cannot be caused.
Therefore, the problem that the power failure verification time of a power grid and a user cannot be coordinated is solved, the accuracy verification of the online error of the current transformer CTx to be detected can be realized without 'injection', the safety performance of online verification is improved, the composition of equipment is reduced, the weight is reduced, the carrying is convenient, and the volume of a system for carrying the current transformer with electricity is reduced.
It is to be noted that the specific embodiments of the apparatus have been described in detail in the above-mentioned specific embodiments of the system, and are not described in detail herein.
In the description of the present application, it should be noted that the terms "upper", "lower", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, which are only for convenience in describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and operate, and thus, should not be construed as limiting the present application. Unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are intended to be inclusive and mean, for example, that they may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.
It is noted that, in the present application, relational terms such as "first" and "second", and the like, are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The above description is merely exemplary of the present application and is presented to enable those skilled in the art to understand and practice the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. The utility model provides a system for electrified check-up current transformer which characterized in that: the system for live-line verification of the current transformer comprises a current transformer to be tested CTx, a standard current transformer CT1, a standard current transformer CT2 and a comprehensive processing device; the current transformer CTx to be tested comprises a primary winding and a secondary winding; the standard current transformer CT1 is connected in series on a primary winding loop of the current transformer to be tested CTx, and the standard current transformer CT2 is connected in series on a secondary winding loop of the current transformer to be tested CTx; and the standard current transformer CT1 and the standard current transformer CT2 are both connected with a comprehensive processing device.
2. The system for live-verifying a current transformer of claim 1, wherein: the standard current transformer CT1 and the standard current transformer CT2 are both pincerlike standard current transformers.
3. The system for live-verifying a current transformer of claim 2, wherein: the standard current transformer CT1 is clamped on a primary winding loop of a current transformer CTx to be tested; the standard current transformer CT2 is clamped on a secondary winding loop of the current transformer CTx to be tested.
4. The system for live-verifying a current transformer of claim 1, wherein: the primary current range of the standard current transformer CT1 is larger than or equal to the primary current range of the current transformer CTx to be tested.
5. The system for live-verifying a current transformer of claim 1, wherein: the comprehensive processing device comprises a signal converter and a check tester, the signal converter and the check tester are integrated into a whole or are arranged independently, and the signal converter is electrically connected with the check tester.
6. The system for live-verifying a current transformer of claim 5, wherein: the checking tester comprises a processor, a data transmission module and a man-machine interaction screen; the processor is respectively in communication connection with the data transmission module, the man-machine interaction screen and the signal converter.
7. The system for live-verifying a current transformer of claim 6, wherein: the checking tester also comprises a power supply module; the power supply module is respectively connected with the processor, the data transmission module and the human-computer interaction screen and used for providing power.
8. The system for live-verifying a current transformer of claim 6, wherein: the signal converter is connected with the processor through two signal channels.
9. The utility model provides an equipment of live calibration current transformer which characterized in that: the equipment for live-line verification of the current transformer comprises a standard current transformer CT1, a standard current transformer CT2 and a comprehensive processing device; the standard current transformer CT1 is connected in series on a primary winding loop of the current transformer to be tested CTx, and the standard current transformer CT2 is connected in series on a secondary winding loop of the current transformer to be tested CTx; and the standard current transformer CT1 and the standard current transformer CT2 are both connected with a comprehensive processing device.
10. The apparatus for live-verifying a current transformer as claimed in claim 9, wherein: the standard current transformer CT1 and the standard current transformer CT2 are both pincerlike standard current transformers; the standard current transformer CT1 is clamped on a primary winding loop of a current transformer CTx to be tested; the standard current transformer CT2 is clamped on a secondary winding loop of the current transformer CTx to be tested.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122001833.8U CN216144940U (en) | 2021-08-24 | 2021-08-24 | System and equipment for live-line checking of current transformer |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202122001833.8U CN216144940U (en) | 2021-08-24 | 2021-08-24 | System and equipment for live-line checking of current transformer |
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| CN216144940U true CN216144940U (en) | 2022-03-29 |
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| CN202122001833.8U Active CN216144940U (en) | 2021-08-24 | 2021-08-24 | System and equipment for live-line checking of current transformer |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116381590A (en) * | 2023-06-07 | 2023-07-04 | 云南电网有限责任公司 | Current transformer electrified checking system, self-calibration method and use method |
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2021
- 2021-08-24 CN CN202122001833.8U patent/CN216144940U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116381590A (en) * | 2023-06-07 | 2023-07-04 | 云南电网有限责任公司 | Current transformer electrified checking system, self-calibration method and use method |
| CN116381590B (en) * | 2023-06-07 | 2023-09-19 | 云南电网有限责任公司 | Current transformer electrified checking system, self-calibration method and use method |
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