CN118169628A - Polarity calibration method and device for current transformer and polarity calibration instrument - Google Patents

Abstract

The invention discloses a polarity verification method and device of a current transformer and a polarity verification instrument. Wherein the method comprises the following steps: obtaining standard specification parameters of a current transformer, wherein the current transformer is a component in a GIS sleeve on the high-voltage side of a main transformer, and the GIS sleeve is used for protecting electric components and wires inside the main transformer; when the main transformer is determined to meet the test conditions, determining the power supply capacity required for verifying the polarity of the current transformer based on the standard specification parameters; when the power supply capacity is determined to meet the test condition, reading the primary side current and the secondary side current of the current transformer by using test equipment so as to verify the polarity of the current transformer; and when the proportional relation between the secondary side current and the primary side current meets the preset proportion, determining that the polarity of the current transformer is correct. The invention solves the technical problems of complex method for checking CT polarity and harsh use condition in the related technology.

Description

Polarity verification method and device for current transformer, and polarity verification instrument

Technical Field

The present invention relates to the technical field of relay protection, and in particular to a polarity verification method and device for a current transformer, and a polarity verification instrument.

Background technique

The current transformer is one of the important equipment in the power system. Its function is to convert the large current on the primary high-voltage side into a small current for use by secondary equipment such as protection, measurement, and metering. At the same time, it isolates the primary equipment from the secondary equipment to ensure the safe use of the secondary equipment. The polarity of the CT (current transformer) refers to the relationship between the current directions of its primary winding and secondary winding, which directly reflects the consistency between the current information obtained by the secondary equipment and the primary current information. Therefore, the CT secondary circuit polarity test is related to the safe and stable operation of the power grid. CT polarity verification is a very important step in the power system to ensure that the current transformer is correctly connected and operated. Incorrect CT polarity may cause the protection device to work abnormally, which may cause power system failures.

Transformer differential protection is the main protection for short-circuit faults inside the transformer and on the lead-out lines. It can respond to phase-to-phase short-circuit inside the transformer and on the lead-out lines, turn-to-turn short-circuit inside the transformer, and single-phase grounding short-circuit faults on the high-current system side. Transformer differential protection, by comparing the size and phase between the same-name phase currents on each side of the transformer, forms a short-circuit zero-start current method on the high-voltage side of the main transformer, that is, using the grounding knife switch at the high-voltage side outlet of the main transformer to form a three-phase short-circuit grounding. It is commonly used in the polarity verification of differential protection of non-first main transformers in conventional power stations and energy-storage power stations. This method is relatively complex, has harsh operating conditions, and requires temporary high-voltage cables, which takes up equipment operation time.

With regard to the problem that the method for verifying CT polarity in the above-mentioned related technologies is relatively complicated and has harsh use conditions, no effective solution has been proposed so far.

Summary of the invention

The embodiments of the present invention provide a polarity verification method and device for a current transformer, and a polarity verification instrument, so as to at least solve the technical problems in the related art that the method for verifying the polarity of a CT is relatively complicated and has harsh use conditions.

According to one aspect of an embodiment of the present invention, a method for checking the polarity of a current transformer is provided, comprising: obtaining standard specification parameters of a current transformer, wherein the current transformer is a component in a GIS bushing on a high-voltage side of a main transformer, and the GIS bushing is used to protect electrical components and wires inside the main transformer; when it is determined that the main transformer meets test conditions, determining a power capacity required for checking the polarity of the current transformer based on the standard specification parameters; when it is determined that the power capacity meets the test conditions, using a test device to read the primary and secondary currents of the current transformer to check the polarity of the current transformer, wherein the primary current represents the current to be measured received by the current transformer, and the secondary current represents the current output from the current transformer that is proportional to the current to be measured; when the proportional relationship between the secondary current and the primary current meets a predetermined ratio, determining that the polarity of the current transformer is correct.

Optionally, determining that the main transformer meets the test conditions includes: inspecting the GIS bushing of the main transformer to obtain an inspection result; when the inspection result indicates that the GIS bushing meets the preset conditions and a predetermined amount of preset gas is contained in the GIS bushing, determining that the main transformer meets the test conditions.

Optionally, determining the power supply capacity required for verifying the polarity of the current transformer includes: determining test parameters for verifying the polarity of the current transformer based on the standard specification parameters; and calculating the power supply capacity using a first formula according to the test parameters, wherein the first formula is: S represents the power supply capacity, _Sn represents the rated power, _Uk represents the short-circuit impedance, _Ik1 represents the primary test current on the high-voltage side of the main transformer, and _In represents the rated current.

Optionally, the current transformer polarity verification method further includes: after determining that the polarity of the current transformer is correct, verifying the differential protection polarity of the main transformer.

Optionally, the differential protection polarity of the main transformer is checked, including: obtaining the connection status of the connecting lines between the test transformer, the test voltage regulator and the main transformer; when the connection status indicates that the connecting lines are well connected, adjusting the first output voltage of the test voltage regulator until the first output voltage corresponds to the second output voltage of the test transformer, and/or adjusting the first output voltage of the test voltage regulator until the first high-voltage side current of the test transformer reaches a predetermined value.

Optionally, before adjusting the first output voltage of the test voltage regulator until the high-voltage side current of the test transformer reaches a predetermined value, the polarity verification method of the current transformer also includes: when the first output voltage of the test voltage regulator is the minimum output voltage, obtaining the second high-voltage side current and the low-voltage side current of the main transformer; judging whether the second high-voltage side current and the low-voltage side current satisfy a predetermined range to obtain a judgment result; when the judgment result indicates that the high-voltage side current and the low-voltage side current do not satisfy the predetermined range, increasing the first output voltage of the test voltage regulator until the second high-voltage side current and the low-voltage side current satisfy the predetermined range.

According to another aspect of an embodiment of the present invention, a polarity verification device for a current transformer is also provided, comprising: an acquisition unit, used to acquire standard specification parameters of the current transformer, wherein the current transformer is a component in the GIS bushing on the high-voltage side of the main transformer, and the GIS bushing is used to protect the electrical components and wires inside the main transformer; a first determination unit, used to determine the power capacity required for verifying the polarity of the current transformer based on the standard specification parameters when it is determined that the main transformer meets the test conditions; a reading unit, used to read the primary side current and the secondary side current of the current transformer using a test device when it is determined that the power capacity meets the test conditions to verify the polarity of the current transformer, wherein the primary side current represents the current to be measured received by the current transformer, and the secondary side current represents the current output from the current transformer that is proportional to the current to be measured; a second determination unit, used to determine that the polarity of the current transformer is correct when the proportional relationship between the secondary side current and the primary side current meets a predetermined ratio.

Optionally, the first determination unit includes: a first acquisition module, used to inspect the GIS bushing of the main transformer to obtain an inspection result; a first determination module, used to determine that the main transformer meets the test condition when the inspection result indicates that the GIS bushing meets the preset condition and the GIS bushing contains a predetermined amount of preset gas.

Optionally, the first determination unit includes: a second determination module, configured to determine a test parameter for verifying the polarity of the current transformer based on the standard specification parameter; and a calculation module, configured to calculate the power supply capacity using a first formula according to the test parameter, wherein the first formula is: S represents the power supply capacity, _Sn represents the rated power, _Uk represents the short-circuit impedance, _Ik1 represents the primary test current on the high-voltage side of the main transformer, and _In represents the rated current.

Optionally, the polarity verification device for the current transformer further includes: a verification unit, configured to verify the polarity of the differential protection of the main transformer after determining that the polarity of the current transformer is correct.

Optionally, the verification unit includes: a second acquisition module, used to obtain the connection status of the connecting lines between the test transformer, the test voltage regulator and the main transformer; a first adjustment module, used to adjust the first output voltage of the test voltage regulator when the connection status indicates that the connecting line is well connected, until the first output voltage corresponds to the second output voltage of the test transformer, and/or, adjust the first output voltage of the test voltage regulator until the first high-voltage side current of the test transformer reaches a predetermined value.

Optionally, the polarity verification device of the current transformer also includes: a third acquisition module, used to obtain the second high-voltage side current and the low-voltage side current of the main transformer when the first output voltage of the test voltage regulator is the minimum output voltage, while adjusting the first output voltage of the test voltage regulator until the high-voltage side current of the test transformer reaches a predetermined value; a fourth acquisition module, used to determine whether the second high-voltage side current and the low-voltage side current meet a predetermined range to obtain a judgment result; and a second adjustment module, used to increase the first output voltage of the test voltage regulator until the second high-voltage side current and the low-voltage side current meet the predetermined range when the judgment result indicates that the high-voltage side current and the low-voltage side current do not meet the predetermined range.

According to another aspect of an embodiment of the present invention, there is also provided a polarity tester for a current transformer, comprising: a test housing, wherein the polarity tester for the current transformer uses any one of the above-mentioned polarity tester methods for the current transformer.

According to another aspect of an embodiment of the present invention, a computer-readable storage medium is further provided, wherein the computer-readable storage medium includes a stored program, wherein the program executes any one of the above-mentioned methods for checking the polarity of a current transformer.

According to another aspect of an embodiment of the present invention, a processor is further provided, and the processor is used to run a program, wherein when the program is run, any one of the above-mentioned methods for checking the polarity of a current transformer is executed.

According to another aspect of an embodiment of the present invention, a computer program product is further provided, comprising computer instructions, wherein when the computer instructions are executed by a processor, any one of the above-mentioned methods for checking the polarity of a current transformer is executed.

In an embodiment of the present invention, standard specification parameters of a current transformer are obtained, wherein the current transformer is a component in a GIS bushing on the high-voltage side of a main transformer, and the GIS bushing is used to protect electrical components and wires inside the main transformer; when it is determined that the main transformer meets the test conditions, the power supply capacity required to verify the polarity of the current transformer is determined based on the standard specification parameters; when it is determined that the power supply capacity meets the test conditions, the primary current and the secondary current of the current transformer are read using a test device to verify the polarity of the current transformer, wherein the primary current represents the current to be measured received by the current transformer, and the secondary current represents the current output from the current transformer that is proportional to the current to be measured; when the proportional relationship between the secondary current and the primary current meets a predetermined ratio, it is determined that the polarity of the current transformer is correct. Through the above technical scheme, the purpose of using the test equipment to read the primary and secondary currents of the current transformer, and then judging whether the polarity of the current transformer is correct by judging whether it conforms to the transformation ratio is achieved, and the technical effect of using simple and easy-to-operate test equipment and test methods to verify the polarity of the current transformer is achieved, thereby solving the technical problems in the related art that the method for verifying the CT polarity is relatively complicated and the use conditions are harsh.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

1 is a hardware structure block diagram of a mobile terminal for a method for checking polarity of a current transformer according to an embodiment of the present invention;

FIG2 is a flow chart of a method for checking the polarity of a current transformer according to an embodiment of the present invention;

3 is a schematic diagram of a polarity tester for a current transformer according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a polarity verification device for a current transformer according to an embodiment of the present invention.

Among them, the above-mentioned drawings include the following figure marks: 1. Inspection machine housing; 2. Handle slide.

Detailed ways

In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

As introduced in the background technology, the method for checking the polarity of CT in the related art is relatively complicated and has harsh use conditions. In view of the above defects, a method and device for checking the polarity of a current transformer and a polarity checker are provided in the embodiments of the present invention.

The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

The method embodiments provided in the embodiments of the present invention can be executed in a mobile terminal, a computer terminal or a similar computing device. Taking running on a mobile terminal as an example, FIG1 is a hardware structure block diagram of a mobile terminal of a current transformer polarity verification method in an embodiment of the present invention. As shown in FIG1 , the mobile terminal may include one or more (only one is shown in FIG1 ) processors 102 (the processor 102 may include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA) and a memory 104 for storing data, wherein the mobile terminal may also include a transmission device 106 and an input/output device 108 for communication functions. It can be understood by those skilled in the art that the structure shown in FIG1 is only for illustration and does not limit the structure of the mobile terminal. For example, the mobile terminal may also include more or fewer components than those shown in FIG1 , or have a configuration different from that shown in FIG1 .

The memory 104 can be used to store computer programs, for example, software programs and modules of application software, such as the computer program corresponding to the polarity verification method of the current transformer in the embodiment of the present invention. The processor 102 executes various functional applications and data processing by running the computer program stored in the memory 104, that is, the above method is implemented. The memory 104 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 may further include a memory remotely arranged relative to the processor 102, and these remote memories can be connected to the mobile terminal via a network. Examples of the above-mentioned network include but are not limited to the Internet, corporate intranets, local area networks, mobile communication networks and combinations thereof. The transmission device 106 is used to receive or send data via a network. The above-mentioned specific examples of the network may include a wireless network provided by a communication provider of the mobile terminal. In one example, the transmission device 106 includes a network adapter (Network Interface Controller, referred to as NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission device 106 may be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

According to an embodiment of the present invention, a method embodiment of a polarity verification method for a current transformer is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

FIG. 2 is a flow chart of a polarity verification method for a current transformer according to an embodiment of the present invention. As shown in FIG. 2 , the method includes the following steps:

Step S202, obtaining standard specification parameters of a current transformer, wherein the current transformer is a component in a GIS bushing on the high-voltage side of a main transformer, and the GIS bushing is used to protect electrical components and wires inside the main transformer.

Optionally, the above standard specification parameters may include but are not limited to the rated transformation ratio, rated voltage, rated current and other parameters of the current transformer.

In this embodiment, the performance and application range of the current transformer can be understood according to the standard specification parameters of the current transformer, so that the test parameters can be correctly set during the test process, thereby ensuring the correctness of the test.

Step S204: when it is determined that the main transformer meets the test conditions, the power capacity required for verifying the polarity of the current transformer is determined based on standard specification parameters.

In this embodiment, it is necessary to ensure that the main transformer, test equipment and instruments can all operate normally and be accurately calibrated before the formal test can be carried out to ensure the safety during the test and the accuracy of the test results.

According to the above embodiment of the present invention, in the above step S204, it is determined that the main transformer meets the test conditions, including: inspecting the GIS bushing of the main transformer to obtain the inspection result; when the inspection result indicates that the GIS bushing meets the preset conditions and the GIS bushing contains a predetermined amount of preset gas, it is determined that the main transformer meets the test conditions.

Optionally, the preset gas may be SF6 gas.

In this embodiment, the GIS bushing, as a gas-insulated metal-enclosed switchgear, can be used to protect the current transformer placed inside it and ensure that the SF6 gas inside it does not leak, so as to play the role of isolation, protection and sealing.

When checking whether the GIS bushing of the main transformer is installed properly, the following steps can be used for inspection: 1) Check the installation record: confirm the installation record of the GIS bushing on the high-voltage side of the main transformer, including the installation date, installer, installation location and other information; 2) Check the installation location: check the installation location of the GIS bushing on the high-voltage side of the main transformer to ensure that it is consistent with the design requirements and has no obvious damage or deformation; 3) Calibrate instruments and equipment: ensure that the test equipment and instruments are calibrated and can accurately measure the relevant parameters of the GIS bushing; 4) Conduct tests: use accurately calibrated test equipment and instruments to test the GIS bushing on the high-voltage side of the main transformer, including electrical parameter tests, sealing tests, etc.; 5) Check gas filling: confirm that qualified SF6 gas has been filled in the GIS, and check the gas filling record to ensure that the filling process meets the requirements; 6) Check the test report: analyze and summarize the test results, generate a test report and review it to ensure that the test results meet the requirements; in this way, it can ensure that the GIS bushing on the high-voltage side of the main transformer has been installed and tested, and at the same time, it can also ensure the safe operation and normal use of the equipment.

In addition, SF6 gas is a special gas used as an insulating medium and arc extinguishing medium. It is mainly used for insulation and arc extinguishing purposes. Ensuring that the GIS bushing is filled with qualified SF6 gas can ensure the normal operation and safe operation of the equipment. At the same time, it can effectively extinguish the arc in the event of a fault to protect the safety of equipment and personnel.

According to the above embodiment of the present invention, in the above step S204, determining the power supply capacity required for verifying the polarity of the current transformer includes: determining the test parameters for verifying the polarity of the current transformer based on the standard specification parameters; and calculating the power supply capacity using a first formula according to the test parameters, wherein the first formula is: S represents the power supply capacity, _Sn represents the rated power, _Uk represents the short-circuit impedance, _Ik1 represents the primary test current on the high-voltage side of the main transformer, and _In represents the rated current.

Optionally, the above test parameters may include but are not limited to: test current, test voltage and other parameters.

In this embodiment, the formula can be used: Calculate the power supply capacity, i.e. the test power supply power, where S represents the power supply capacity, _Sn represents the rated power, _Uk represents the short-circuit impedance, _Ik1 represents the primary test current on the high-voltage side of the main transformer, and _In represents the rated current; the required test voltage can be obtained using the formula:/> Calculation is performed, where U represents the test voltage on the high voltage side of the main transformer and _Un represents the rated voltage.

Step S206, when it is determined that the power supply capacity meets the test conditions, the primary side current and the secondary side current of the current transformer are read by the test equipment to verify the polarity of the current transformer, wherein the primary side current represents the current to be measured received by the current transformer, and the secondary side current represents the current output from the current transformer that is proportional to the current to be measured.

The above embodiment of the present invention is described in detail below in conjunction with FIG3 , which is a schematic diagram of a polarity tester for a current transformer according to an embodiment of the present invention. As shown in FIG3 , the structural isometric view of the polarity tester is shown, in which the side wall of the bottom of the tester housing 1 that contacts the ground is fixedly connected to the handle slide 2 .

When using the polarity tester to test the polarity of the current transformer in the main transformer, the polarity tester tester housing is connected to the primary and secondary sides of the current transformer, and a known test current is applied to the primary side of the current transformer at the same time. Then, the polarity tester is used to read the secondary current of the current transformer, wherein the secondary current is obtained by the transformation ratio of the primary current. Here, the polarity of the current transformer is mainly judged by verifying whether the secondary current of the voltage transformer is the same as the primary current after the transformation ratio calculation. Generally speaking, if the polarity of the current transformer is correct, then after a test current is applied to the primary side of the current transformer, the current read on the secondary side of the current transformer should be the same as the primary current after the transformation ratio calculation.

It should be noted that the primary side of the current transformer refers to the side of the current transformer that is directly related to the current being measured, and is usually connected to the current being measured through a wire or current carrier; the secondary side of the current transformer refers to the side of the current transformer that outputs the current, and is usually converted into a standard secondary current output through the transformer principle, which is used to connect to measuring instruments or other equipment for further processing.

Step S208: When the ratio of the secondary current to the primary current satisfies a predetermined ratio, it is determined that the polarity of the current transformer is correct.

In this embodiment, the primary current of the current transformer is converted into the secondary current of the current transformer through the transformer principle, that is, the secondary current is obtained by the primary current after the transformation ratio; here, whether the polarity of the current transformer is correct can be judged by judging whether the ratio between the secondary current and the primary current satisfies the transformation ratio, and whether the polarity of the current transformer is correct can also be judged by comparing whether the read secondary current is consistent with the value of the primary current after the transformation ratio.

According to the above embodiment of the present invention, the polarity verification method of the current transformer further includes: after determining that the polarity of the current transformer is correct, verifying the polarity of the differential protection of the main transformer.

In this embodiment, after testing the polarity of the current transformer, it is also necessary to verify the polarity of the differential protection of the main transformer in a small range. By verifying the polarity of the differential protection of the main transformer in a small range, it can help confirm that the differential protection device of the main transformer in a small range can correctly detect the current on the high and low voltage sides of the main transformer in actual operation, thereby achieving accurate monitoring and protection of the operating status of the main transformer; by verifying the polarity of the differential protection of the main transformer in a small range, it can also ensure that the differential protection device of the main transformer in a small range can accurately identify the operating status of the main transformer when the protection trips, thereby effectively protecting the safe operation of the main transformer equipment and the power system. The method for verifying the polarity of the differential protection of the main transformer in a small range is described in detail below, which will not be repeated here.

In the above-mentioned embodiment of the present invention, the differential protection polarity of the main transformer is checked, including: obtaining the connection status of the connecting lines between the test transformer, the test voltage regulator and the main transformer; when the connection status indicates that the connecting lines are well connected, adjusting the first output voltage of the test voltage regulator until the first output voltage corresponds to the second output voltage of the test transformer, and/or adjusting the first output voltage of the test voltage regulator until the first high-voltage side current of the test transformer reaches a predetermined value.

First, connect the connecting wires between the test transformer, the test voltage regulator and the main transformer; then, adjust the output voltage protection of the test voltage regulator to correspond to the output voltage of the test transformer and perform a trip test; and/or, adjust the output voltage of the test voltage regulator until the current on the high-voltage side of the test transformer reaches 15A and remains stable.

The purpose of checking the differential protection polarity of the main transformer here is to confirm that the small-scale differential protection device of the main transformer is working properly and that the protection device can correctly monitor and protect the voltage and current of the main transformer.

The tripping test here refers to the differential protection device of the main transformer in a small range, to confirm that when the protection action conditions are met, the device can trip accurately and timely to protect the safety and reliability of the equipment and system.

In this embodiment, before adjusting the first output voltage of the test voltage regulator until the high-voltage side current of the test transformer reaches a predetermined value, the polarity verification method of the current transformer also includes: when the first output voltage of the test voltage regulator is the minimum output voltage, obtaining the second high-voltage side current and the low-voltage side current of the main transformer; judging whether the second high-voltage side current and the low-voltage side current satisfy a predetermined range, and obtaining a judgment result; when the judgment result indicates that the high-voltage side current and the low-voltage side current do not satisfy the predetermined range, increasing the first output voltage of the test voltage regulator until the second high-voltage side current and the low-voltage side current satisfy the predetermined range.

Before adjusting the output voltage of the test voltage regulator until the current on the high-voltage side of the test transformer reaches the predetermined range, it is necessary to make a zero adjustment on the test voltage regulator to ensure that the current of the current transformer on the high-voltage side of the main transformer is within the normal range.

Here you can first adjust the test voltage regulator to the minimum position, monitor the current of the current transformer on the high-voltage side of the main transformer during the adjustment process, and after confirming that the current of the current transformer on the high-voltage side of the main transformer is within the normal range, slowly adjust the output voltage of the test voltage regulator until the current on the high-voltage side of the test transformer reaches 15A and remains stable.

It can be seen from the above that through the above steps, the standard specification parameters of the current transformer can be obtained, wherein the current transformer is a component in the GIS bushing on the high-voltage side of the main transformer, and the GIS bushing is used to protect the electrical components and wires inside the main transformer; when it is determined that the main transformer meets the test conditions, the power supply capacity required to verify the polarity of the current transformer is determined based on the standard specification parameters; when it is determined that the power supply capacity meets the test conditions, the primary and secondary currents of the current transformer are read using the test equipment to verify the polarity of the current transformer, wherein the primary current represents the current transformer to be tested. Current, the secondary current represents the current output from the current transformer that is proportional to the current to be measured; when the proportional relationship between the secondary current and the primary current meets the predetermined ratio, it is determined that the polarity of the current transformer is correct, thereby achieving the purpose of using the test equipment to read the primary current and the secondary current of the current transformer, and then judging whether the polarity of the current transformer is correct by judging whether it meets the transformation ratio, and achieving the technical effect of using simple and easy-to-operate test equipment and test methods to verify the polarity of the current transformer, thereby solving the technical problem that the method for verifying the polarity of CT in the related art is relatively complicated and the use conditions are harsh.

Therefore, the technical solution provided by the above-mentioned embodiment of the present invention solves the technical problem that the method for verifying CT polarity in the related art is relatively complicated and has harsh use conditions.

It should be noted that, for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the described order of actions, because according to the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present application.

Through the description of the above implementation methods, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM/RAM, magnetic disk, optical disk), and includes a number of instructions for a terminal device (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods described in each embodiment of the present application.

According to an embodiment of the present invention, a polarity verification device for a current transformer for implementing the polarity verification method of the current transformer is also provided. FIG4 is a schematic diagram of a polarity verification device for a current transformer according to an embodiment of the present invention. As shown in FIG4, the device includes: an acquisition unit 41, a first determination unit 43, a reading unit 45, and a second determination unit 47. The device is described in detail below.

The acquisition unit 41 is used to acquire standard specification parameters of a current transformer, wherein the current transformer is a component in a GIS bushing on the high-voltage side of a main transformer, and the GIS bushing is used to protect electrical components and wires inside the main transformer.

The first determination unit 43 is used to determine the power capacity required for verifying the polarity of the current transformer based on standard specification parameters when it is determined that the main transformer meets the test conditions.

The reading unit 45 is used to read the primary current and secondary current of the current transformer using the test equipment when it is determined that the power supply capacity meets the test conditions, so as to verify the polarity of the current transformer, wherein the primary current represents the current to be measured received by the current transformer, and the secondary current represents the current output from the current transformer that is proportional to the current to be measured.

The second determining unit 47 is used to determine that the polarity of the current transformer is correct when the ratio of the secondary side current to the primary side current satisfies a predetermined ratio.

It should be noted here that the above-mentioned acquisition unit 41, first determination unit 43, reading unit 45 and second determination unit 47 correspond to steps S202 to S208 in the above-mentioned embodiments, and the four units are the same as the instances and application scenarios implemented by the corresponding steps, but are not limited to the contents disclosed in the above-mentioned embodiments.

As can be seen from the above, in the scheme recorded in the above embodiment of the present invention, the acquisition unit can be used to obtain the standard specification parameters of the current transformer, wherein the current transformer is a component in the GIS bushing on the high-voltage side of the main transformer, and the GIS bushing is used to protect the electrical components and wires inside the main transformer; then, when the main transformer is determined to meet the test conditions, the first determination unit is used to determine the power capacity required for verifying the polarity of the current transformer based on the standard specification parameters; and then, when the reading unit is determined to meet the test conditions, the test equipment is used to read the primary and secondary currents of the current transformer to verify the polarity of the current transformer, wherein the primary current meter The primary side current represents the current to be measured received by the current transformer, and the secondary side current represents the current output from the current transformer that is proportional to the current to be measured; finally, the second determining unit is used to determine that the polarity of the current transformer is correct when the proportional relationship between the secondary side current and the primary side current meets the predetermined ratio, thereby achieving the purpose of using the test equipment to read the primary side current and the secondary side current of the current transformer, and then judging whether the polarity of the current transformer is correct by judging whether it meets the transformation ratio, and achieving the technical effect of using simple and easy-to-operate test equipment and test methods to verify the polarity of the current transformer, thereby solving the technical problems in the related art that the method for verifying the CT polarity is relatively complicated and the use conditions are harsh.

Therefore, the technical solution provided by the above-mentioned embodiment of the present invention solves the technical problem that the method for verifying CT polarity in the related art is relatively complicated and has harsh use conditions.

Optionally, the first determination unit includes: a first acquisition module, used to inspect the GIS bushing of the main transformer and obtain an inspection result; a first determination module, used to determine that the main transformer meets the test condition when the inspection result indicates that the GIS bushing meets the preset condition and the GIS bushing contains a predetermined amount of preset gas.

Optionally, the first determination unit includes: a second determination module, used to determine a test parameter for verifying the polarity of the current transformer based on a standard specification parameter; and a calculation module, used to calculate the power supply capacity using a first formula according to the test parameter, wherein the first formula is: S represents the power supply capacity, _Sn represents the rated power, _Uk represents the short-circuit impedance, _Ik1 represents the primary test current on the high-voltage side of the main transformer, and _In represents the rated current.

Optionally, the polarity verification device for the current transformer further includes: a verification unit, configured to verify the polarity of the differential protection of the main transformer after determining that the polarity of the current transformer is correct.

Optionally, the verification unit includes: a second acquisition module, used to obtain the connection status of the connecting lines between the test transformer, the test voltage regulator and the main transformer; a first adjustment module, used to adjust the first output voltage of the test voltage regulator when the connection status indicates that the connecting line is well connected, until the first output voltage corresponds to the second output voltage of the test transformer, and/or, adjust the first output voltage of the test voltage regulator until the first high-voltage side current of the test transformer reaches a predetermined value.

Optionally, the polarity verification device of the current transformer also includes: a third acquisition module, used to adjust the first output voltage of the test voltage regulator until the high-voltage side current of the test transformer reaches a predetermined value, and obtain the second high-voltage side current and the low-voltage side current of the main transformer when the first output voltage of the test voltage regulator is the minimum output voltage; a fourth acquisition module, used to determine whether the second high-voltage side current and the low-voltage side current meet a predetermined range and obtain a judgment result; a second adjustment module, used to increase the first output voltage of the test voltage regulator until the second high-voltage side current and the low-voltage side current meet the predetermined range when the judgment result indicates that the high-voltage side current and the low-voltage side current do not meet the predetermined range.

According to another aspect of an embodiment of the present invention, a polarity tester for a current transformer is provided, comprising: a test housing, wherein the polarity tester for a current transformer uses any of the above-mentioned polarity tester methods for a current transformer.

According to another aspect of an embodiment of the present invention, a computer-readable storage medium is further provided. The computer-readable storage medium includes a stored program, wherein the program executes any one of the above-mentioned polarity verification methods for a current transformer.

Optionally, in this embodiment, the computer-readable storage medium may be located in any one of the computer terminals in a computer terminal group in a computer network, or in any one of the communication devices in a communication device group.

Optionally, in this embodiment, the computer-readable storage medium is configured to store program code for performing the following steps: obtaining standard specification parameters of the current transformer, wherein the current transformer is a component in the GIS bushing on the high-voltage side of the main transformer, and the GIS bushing is used to protect the electrical components and wires inside the main transformer; when it is determined that the main transformer meets the test conditions, determining the power capacity required to verify the polarity of the current transformer based on the standard specification parameters; when it is determined that the power capacity meets the test conditions, using the test equipment to read the primary and secondary currents of the current transformer to verify the polarity of the current transformer, wherein the primary current represents the current to be measured received by the current transformer, and the secondary current represents the current output from the current transformer that is proportional to the current to be measured; when the proportional relationship between the secondary current and the primary current meets a predetermined ratio, determining that the polarity of the current transformer is correct.

Optionally, in this embodiment, the computer-readable storage medium is configured to store program codes for executing the following steps: inspecting the GIS bushing of the main transformer to obtain an inspection result; when the inspection result indicates that the GIS bushing meets a preset condition and the GIS bushing contains a predetermined amount of preset gas, determining that the main transformer meets the test condition.

Optionally, in this embodiment, the computer-readable storage medium is configured to store program codes for executing the following steps: determining test parameters for verifying the polarity of the current transformer based on standard specification parameters; and calculating the power supply capacity using a first formula according to the test parameters, wherein the first formula is: S represents the power supply capacity, _Sn represents the rated power, _Uk represents the short-circuit impedance, _Ik1 represents the primary test current on the high-voltage side of the main transformer, and _In represents the rated current.

Optionally, in this embodiment, the computer-readable storage medium is configured to store program codes for executing the following steps: after determining that the polarity of the current transformer is correct, verifying the polarity of the differential protection of the main transformer.

Optionally, in this embodiment, the computer-readable storage medium is configured to store program code for performing the following steps: obtaining the connection status of the connecting lines between the test transformer, the test voltage regulator and the main transformer; when the connection status indicates that the connecting lines are well connected, adjusting the first output voltage of the test voltage regulator until the first output voltage corresponds to the second output voltage of the test transformer, and/or adjusting the first output voltage of the test voltage regulator until the first high-voltage side current of the test transformer reaches a predetermined value.

Optionally, in this embodiment, the computer-readable storage medium is configured to store program codes for executing the following steps: when the first output voltage of the test voltage regulator is the minimum output voltage, obtaining the second high-voltage side current and the low-voltage side current of the main transformer; judging whether the second high-voltage side current and the low-voltage side current satisfy a predetermined range, and obtaining a judgment result; when the judgment result indicates that the high-voltage side current and the low-voltage side current do not satisfy the predetermined range, increasing the first output voltage of the test voltage regulator until the second high-voltage side current and the low-voltage side current satisfy the predetermined range.

According to another aspect of an embodiment of the present invention, a processor is further provided, and the processor is used to run a program, wherein when the program is run, any one of the above-mentioned polarity verification methods for a current transformer is executed.

According to another aspect of an embodiment of the present invention, a computer program product is further provided, comprising computer instructions, and when the computer instructions are executed by a processor, any one of the above-mentioned methods for checking the polarity of a current transformer is executed.

The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes.

The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims (10)

1. A method for checking the polarity of a current transformer, comprising: Obtaining standard specification parameters of a current transformer, wherein the current transformer is a component in a GIS bushing on the high-voltage side of a main transformer, and the GIS bushing is used to protect electrical components and wires inside the main transformer; When it is determined that the main transformer meets the test conditions, determining the power supply capacity required for verifying the polarity of the current transformer based on the standard specification parameters; When it is determined that the power supply capacity meets the test conditions, the primary side current and the secondary side current of the current transformer are read by the test equipment to verify the polarity of the current transformer, wherein the primary side current represents the current to be measured received by the current transformer, and the secondary side current represents the current outputted from the current transformer and is proportional to the current to be measured; When the proportional relationship between the secondary side current and the primary side current satisfies a predetermined ratio, it is determined that the polarity of the current transformer is correct. 2. The polarity verification method of a current transformer according to claim 1, characterized in that determining that the main transformer meets the test conditions comprises: Inspecting the GIS bushing of the main transformer to obtain an inspection result; When the inspection result indicates that the GIS bushing meets the preset condition and a predetermined amount of preset gas is contained in the GIS bushing, it is determined that the main transformer meets the test condition. 3. The polarity verification method of a current transformer according to claim 1, characterized in that determining the power supply capacity required for verifying the polarity of the current transformer comprises: Determining test parameters for verifying the polarity of the current transformer based on the standard specification parameters; The power supply capacity is calculated using a first formula according to the test parameters, wherein the first formula is: S represents the power supply capacity, _Sn represents the rated power, _Uk represents the short-circuit impedance, _Ik1 represents the primary test current on the high-voltage side of the main transformer, and _In represents the rated current. 4. The polarity verification method of a current transformer according to claim 1, further comprising: After determining that the polarity of the current transformer is correct, the polarity of the differential protection of the main transformer is checked. 5. The polarity verification method of a current transformer according to claim 4, characterized in that the polarity of the differential protection of the main transformer is verified, comprising: Obtaining the connection status of the connecting wires between the test transformer, the test voltage regulator and the main transformer; When the connection state indicates that the connecting line is well connected, adjust the first output voltage of the test voltage regulator until the first output voltage corresponds to the second output voltage of the test transformer, and/or adjust the first output voltage of the test voltage regulator until the first high-voltage side current of the test transformer reaches a predetermined value. 6. The polarity verification method of a current transformer according to claim 5, characterized in that before adjusting the first output voltage of the test voltage regulator until the high-voltage side current of the test transformer reaches a predetermined value, it further comprises: When the first output voltage of the test voltage regulator is a minimum output voltage, obtaining a second high-voltage side current and a low-voltage side current of the main transformer; Determine whether the second high-voltage side current and the low-voltage side current meet a predetermined range, and obtain a determination result; When the judgment result indicates that the high-voltage side current and the low-voltage side current do not satisfy the predetermined range, the first output voltage of the test voltage regulator is increased until the second high-voltage side current and the low-voltage side current satisfy the predetermined range. 7. A polarity verification device for a current transformer, comprising: An acquisition unit, used for acquiring standard specification parameters of a current transformer, wherein the current transformer is a component in a GIS bushing on a high voltage side of a main transformer, and the GIS bushing is used for protecting electrical components and wires inside the main transformer; A first determining unit, configured to determine, when determining that the main transformer meets the test condition, a power supply capacity required for verifying the polarity of the current transformer based on the standard specification parameters; A reading unit, configured to read the primary side current and the secondary side current of the current transformer by using a test device when it is determined that the power supply capacity meets the test conditions, so as to verify the polarity of the current transformer, wherein the primary side current represents the current to be measured received by the current transformer, and the secondary side current represents the current outputted from the current transformer and in proportional relationship with the current to be measured; The second determining unit is used to determine that the polarity of the current transformer is correct when the proportional relationship between the secondary side current and the primary side current satisfies a predetermined proportion. 8. A polarity tester for a current transformer, characterized in that it comprises: a test housing, wherein the polarity tester for a current transformer uses the polarity test method for a current transformer according to any one of claims 1 to 6. 9. A computer-readable storage medium, characterized in that the computer-readable storage medium comprises a stored program, wherein the program executes the polarity verification method for a current transformer according to any one of claims 1 to 6. 10. A computer program product, comprising computer instructions, characterized in that when the computer instructions are executed by a processor, the polarity verification method for a current transformer according to any one of claims 1 to 6 is executed.