Online calibration method and system for automatic verification system of low-voltage current transformer

Abstract

The invention discloses an online calibration method and system for an automatic verification system of a low-voltage current transformer, and belongs to the technical field of precision measurement. The method comprises the steps that a miniaturized standard current transformer serves as a detected current transformer, the detected current transformer is online to an automatic detection system of the detected low-voltage current transformer, and the detected current transformer is calibrated based on the automatic detection system of the detected low-voltage current transformer; reading a calibration result of the detected current transformer; and the calibration result is converted into a basic error of the automatic verification system of the detected low-voltage current transformer, and whether the metering performance of the error measurement unit of the automatic verification system of the detected low-voltage current transformer is qualified is calibrated based on the basic error. Calibration can be completed without disassembling the system, through online calibration, the workload is small, the verification efficiency is high, and system problems caused by disassembling are avoided.

Description

Technical Field

[0001] The present invention relates to the field of precision measurement technology, and more specifically, to an online calibration method and system for an automatic verification system of a low-voltage current transformer. Background Art

[0002] The automatic verification system for electric energy metering instruments is an intelligent verification system that integrates automatic transmission facilities and fully automatic verification devices for electric energy metering instruments. It can complete the automatic transmission, verification, monitoring and data processing of electric energy metering instruments, and can meet the centralized verification of large quantities of standardized electric energy metering instruments. The centralized verification through the automated verification system eliminates the differences in verification quality caused by human and regional factors, effectively improves the work quality and efficiency of measurement verification, and is a major initiative of the State Grid Corporation of China to standardize the measurement management methods and business processes of electric energy metering instruments, achieve the full life cycle management goals, innovate management methods and operation mechanisms, and improve the level of measurement asset management.

[0003] Since 2014, the automatic verification system for electric energy metering instruments has been widely used in various provincial grid companies, and has effectively supported the verification / detection of electric energy metering instruments. However, with the technological progress of electric energy metering instruments and the rapid development of power grids, their detection capabilities and intelligent supervision levels are still in a relatively backward stage, which is specifically manifested in the following aspects: First, the traditional value traceability method is time-consuming and inefficient. The current value traceability is based on the existing JJG-1139 "Automated Verification System for Low-voltage Current Transformers for Measurement" verification procedures for periodic traceability. The value traceability of the automated verification system requires the shutdown and disassembly of standard equipment. Repeated disassembly and assembly accelerates the aging of contact points and affects the overall metering performance of the verification system. Summary of the invention

[0004] In view of the above problems, the present invention proposes an online calibration method for a low-voltage current transformer automatic verification system, comprising:

[0005] A miniaturized standard current transformer is used as a current transformer to be tested, and is put online to an automated verification system for a low-voltage current transformer to be tested, and the current transformer to be tested is calibrated based on the automated verification system for the low-voltage current transformer to be tested;

[0006] Read the calibration result of the current transformer under test;

[0007] The calibration result is converted into a basic error of the automated verification system for the low-voltage current transformer under test, and based on the basic error, the measurement performance of the error measurement unit of the automated verification system for the low-voltage current transformer under test is calibrated to determine whether it is qualified.

[0008] Optionally, the calibration results include: the ratio difference and phase difference measured by the basic error measurement unit of the automated verification system for the low-voltage current transformer under test, and the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measurement points.

[0009] Optionally, basic errors include: ratio difference and phase difference of basic error measurement units of the automated verification system for the low-voltage current transformer under test.

[0010] Optionally, based on the following conversion, the test result is converted into the basic error of the automatic test system of the low-voltage current transformer under test. The conversion formula is as follows:

[0011] f x =-f0+f p

[0012] δ x =-δ0+δ p

[0013] Among them, f x and δ x f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively. f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively. p and δ p They are the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measuring points.

[0014] Optionally, if the miniaturized standard current transformer is two or more accuracy levels higher than the low-voltage current transformer automated verification system being tested, the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measuring point are not taken into account. Therefore, the conversion formula is as follows:

[0015] f x =-f0

[0016] δ x =-δ0

[0017] Among them, f x and δ x are the ratio difference and phase difference of the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively; f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively.

[0018] Optionally, based on a standard current transformer basic error limit table, the automated verification system for the low-voltage current transformer under test is calibrated to determine whether it is qualified according to the basic error.

[0019] On the other hand, the present invention also proposes an online verification system for a low-voltage current transformer automatic calibration system, comprising:

[0020] A calibration unit, used for calibrating the current transformer under test based on the automatic calibration system of the low-voltage current transformer under test;

[0021] Among them, a miniaturized standard current transformer is used as the current transformer to be tested and connected to the automatic verification system of the low-voltage current transformer to be tested;

[0022] An output unit, used for reading the calibration result of the current transformer under test;

[0023] The judgment unit is used to convert the calibration result into the basic error of the automatic verification system of the low-voltage current transformer under test, and based on the basic error, calibrate whether the measurement performance of the error measurement unit of the automatic verification system of the low-voltage current transformer under test is qualified.

[0024] Optionally, the calibration results include: the ratio difference and phase difference measured by the basic error measurement unit of the automated verification system for the low-voltage current transformer under test, and the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measurement points.

[0025] Optionally, basic errors include: ratio difference and phase difference of basic error measurement units of the automated verification system for the low-voltage current transformer under test.

[0026] Optionally, based on the following conversion, the test result is converted into the basic error of the automatic test system of the low-voltage current transformer under test. The conversion formula is as follows:

[0027] f x =-f0+f p

[0028] δ x =-δ0+δ p

[0029] Among them, f x and δ x f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively. f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively. p and δ p They are the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measuring points.

[0030] Optionally, if the miniaturized standard current transformer is two or more accuracy levels higher than the low-voltage current transformer automated verification system being tested, the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measuring point are not taken into account. Therefore, the conversion formula is as follows:

[0031] f x =-f0

[0032] δ x =-δ0

[0033] Among them, f x and δ x are the ratio difference and phase difference of the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively; f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively.

[0034] Optionally, based on a standard current transformer basic error limit table, the automated verification system for the low-voltage current transformer under test is calibrated to determine whether it is qualified according to the basic error.

[0035] In yet another aspect, the present invention further provides a computing device, comprising: one or more processors;

[0036] a processor for executing one or more programs;

[0037] When the one or more programs are executed by the one or more processors, the above-described method is implemented.

[0038] In yet another aspect, the present invention further provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed, the method described above is implemented.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The present invention provides an online calibration method for a low-voltage current transformer automatic verification system, comprising: taking a miniaturized standard current transformer as a current transformer to be tested, going online to the low-voltage current transformer automatic verification system to be tested, calibrating the current transformer to be tested based on the low-voltage current transformer automatic verification system to be tested; reading the calibration result of the current transformer to be tested; converting the calibration result into the basic error of the low-voltage current transformer automatic verification system to be tested, and calibrating whether the metrological performance of the error measurement unit of the low-voltage current transformer automatic verification system to be tested is qualified based on the basic error. The present invention can complete the calibration without disassembling the system, and through online calibration, the workload is small, the verification efficiency is high, and the system problems caused by disassembly are avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is the structure diagram of the verification system;

[0042] Figure 2 is a flow chart of the method of the present invention;

[0043] Figure 3 It is a structural diagram of the system of the present invention. DETAILED DESCRIPTION

[0044] Now, exemplary embodiments of the present invention are described with reference to the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely and to fully convey the scope of the present invention to those skilled in the art. The terms used in the exemplary embodiments shown in the accompanying drawings are not intended to limit the present invention. In the accompanying drawings, the same units / elements are marked with the same reference numerals.

[0045] Unless otherwise specified, the terms (including technical terms) used herein have the commonly understood meanings to those skilled in the art. In addition, it is understood that the terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0046] Embodiment 1:

[0047] The schematic diagram of the low voltage current transformer verification system is as follows: Figure 1 As shown in the figure, it adopts modular design and is mainly composed of a calibration system management platform, automatic transmission facilities and a fully automatic transformer calibration device. The calibration system management platform consists of calibration system management software, calibration software, control software, etc. It accepts the inspection plan issued by the production scheduling platform, manages and controls the entire calibration system, and reports the calibration results and packaging information to the production scheduling platform. The automatic transmission facility consists of pre-processing, loading, conveying, identification and positioning, sorting and labeling, unloading, post-processing and other units to complete the transportation and positioning of the transformer during the calibration process. The fully automatic transformer calibration device consists of insulation resistance measurement, power frequency withstand voltage test, secondary winding inter-turn insulation strength test, basic error measurement, magnetic saturation margin measurement and other units, and automatically completes the calibration operation of the low-voltage current transformer according to the requirements of the calibration regulations.

[0048] The automated verification system is widely used in the large-scale automatic verification of electric energy metering instruments (including low-voltage current transformers, single-phase electric energy meters and three-phase electric energy meters, etc.). It is a measurement standard with high accuracy, complex measurement process and important measurement results. The national metrological verification regulations JJG 1139-2017 "Verification Regulations for Automated Verification Systems of Low-voltage Current Transformers for Measurement" has been issued for the automated verification system of low-voltage current transformers. Its periodic verification is usually carried out in accordance with the regulations, and the verification is carried out at regular intervals to ensure the accuracy and reliability of the measurement performance. According to JJG 1139-2017 "Verification Regulations for Automated Verification Systems of Low-voltage Current Transformers for Measurement", the unit error measurement requires checking that the standard current transformer, transformer tester, and transformer load box have valid verification / calibration certificates. Therefore, traditional periodic calibration requires the standard current transformer, transformer tester, and transformer load box to be removed from the automated calibration system, and then sent for separate inspection. After the calibration is completed, they must be installed back into the calibration system. This traceability method is time-consuming and inefficient, and frequent disassembly and assembly of standard devices will affect the performance of the contact points and standards. It is necessary to explore a new online calibration method.

[0049] Since the automated calibration system is an integrated device with multiple devices and multiple functions, it involves multiple disciplines such as mechanics, electrical, control, and automation. If classified by function, it can be divided into five categories: transmission function, data transmission function, identification and positioning function, measurement and measurement function, and electrical safety measurement function. Most of the functions cannot be accurately displayed through data. Only the error measurement function is a true value measurement. The accuracy of its measurement is directly related to the measurement of people's livelihood and is the most concerned issue in traceability. Therefore, this calibration method only targets the ratio difference and phase difference of the error measurement unit of the low-voltage current transformer automated calibration system. According to the JJG 313 measurement transformer, the traceability of the standard current transformer is two levels higher than that of the calibrated transformer. Therefore, according to the above-mentioned standards, the present invention proposes an online calibration method for a low-voltage current transformer automated calibration system.

[0050] Traditional traceability is to dismantle the standard current transformer in the automated verification system and use a higher-level double-stage current transformer or current comparator to perform error verification on it. Usually, this type of standard current transformer has a high accuracy level and is relatively large in size. In order to achieve online calibration of the automated verification system for electric energy metering instruments, the current ratio standard device must first be miniaturized and lightweight. Because the current standard current transformers of the same accuracy level are both large in size and weight, they cannot meet the online verification requirements of the automated verification system. Therefore, the present invention uses a miniaturized standard device for verification;

[0051] The method of the present invention, such as Figure 2 As shown, including:

[0052] Step 1: Using a miniaturized standard current transformer as a current transformer to be tested, and putting it online to an automated verification system for a low-voltage current transformer to be tested, and calibrating the current transformer to be tested based on the automated verification system for the low-voltage current transformer to be tested;

[0053] Step 2, reading the calibration result of the current transformer under test;

[0054] Step 3: convert the calibration result into the basic error of the automatic verification system of the low-voltage current transformer under test, and based on the basic error, calibrate whether the metrological performance of the error measurement unit of the automatic verification system of the low-voltage current transformer under test is qualified.

[0055] The calibration results include: the ratio difference and phase difference measured by the basic error measurement unit of the automated verification system for the low-voltage current transformer under test, and the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measurement points.

[0056] Among them, the basic error includes: the ratio difference and phase difference of the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test.

[0057] Among them, based on the following conversion, the verification result is converted into the basic error of the automatic verification system of the low-voltage current transformer under test. The conversion formula is as follows:

[0058] f x =-f0+f p

[0059] δ x =-δ0+δ p

[0060] Among them, f x and δ x f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively. f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively. p and δ p They are the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measuring points.

[0061] Among them, if the miniaturized standard current transformer is two or more accuracy levels higher than the low-voltage current transformer automated verification system being measured, the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measuring point are not taken into account. Therefore, the conversion formula is as follows:

[0062] f x =-f0

[0063] δ x =-δ0

[0064] Among them, f x and δ x are the ratio difference and phase difference of the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively; f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively.

[0065] Wherein, based on the standard current transformer basic error limit table, according to the basic error, the automatic verification system of the low-voltage current transformer under test is calibrated to determine whether it is qualified.

[0066] The method of the present invention is further described below with reference to specific cases:

[0067] According to JJG 1139-2017, the traditional traceability method is to remove the standard current transformer, transformer calibrator and transformer load box of the error measurement unit separately and send them to the upper-level standard laboratory for calibration. The current online calibration method regards the standard current transformer, transformer calibrator and transformer load box as a whole, which is similar to the idea of ​​transformer calibration device calibration, and then uses a high-level standard current transformer to trace the whole.

[0068] The standard instrument and the low-voltage current transformer under test are measured by direct measurement under the same rated ratio. The specific test method is as follows: the miniaturized standard current transformer is used as the current transformer under test, and it is put online to the automatic verification system for normal verification, and the basic error test is carried out. The ratio difference and phase difference of the current transformer are read from the automatic verification system, and converted into the basic error of the automatic verification system using the following formula.

[0069] Ratio difference f x :

[0070] f x =-f0+f p (1)

[0071] Where: f x - Ratio difference of basic error measurement unit of automated verification system;

[0072] f0-the ratio difference measured by the basic error measurement unit of the automated verification system;

[0073] f p - Ratio difference of miniaturized standard current transformer at corresponding measuring points.

[0074] Phase difference δ x :

[0075] δ x =-δ0+δp (2)

[0076] Where: x - Ratio difference of basic error measurement unit of automated verification system;

[0077] δ0-ratio difference measured by the basic error measurement unit of the automated verification system;

[0078] δ p - Ratio difference of miniaturized standard current transformer at corresponding measuring points.

[0079] When the standard is two or more accuracy levels higher than the low voltage current transformer automated verification system being tested, the ratio difference f of the standard current transformer p and phase difference δ p Can be ignored.

[0080] That is, the following expression:

[0081] f x =-f0 (3)

[0082] δ x =-δ0 (4)

[0083] Refer to the ratio difference and phase difference and the basic error limit table of standard current transformers, as shown in Table 1, to determine whether the automated verification system is qualified.

[0084] Table 1

[0085]

[0086] This idea can refer to the error calibration method of JJF (Fujian) 1048-2011 "Calibration Specifications for Current Transformer Field Calibrators".

[0087] The present invention only targets the core measurement unit of the automated verification system, and other insulation and withstand voltage units and mechanical crimping functions are not within the scope of consideration of this method.

[0088] Since the automatic verification system of the low-voltage current transformer to be tested has many transformation ratios, and the online standard mentioned above only has a single transformation ratio, a single standard can only meet the calibration of a single transformation ratio. Therefore, in order to meet the measurement performance verification requirements, how to complete the online traceability more efficiently is a problem we need to consider.

[0089] The automatic calibration system generally calibrates 5 types of transformers, including LMZ1D: 75-150A; LMZ2D: 200-500A; LMZ3D: 600-800A; LMZ4D: 1000-1500A; LMZ5D: 2000-3000A. Each model selects a current ratio, which can correspond to 5 types of transformers respectively, and the inspection line can detect the calibration capabilities of different types of transformers.

[0090] The workstations of the automated verification system are generally grouped into 12. For a ratio test, 1-12 transformers can be measured at a time. For online calibration, you can select (1-12) transformers. The more you select, the more data information you get. When more than 2 transformers are tested, the consistency of the workstations can be obtained through data analysis.

[0091] Calibration and verification are both ways to trace the value of measuring instruments, and are also important means to ensure accurate and reliable measurement performance. This calibration method can provide technical support for the online calibration of the automated verification system in the future. If the subsequent technology matures, it can gradually replace the periodic verification. However, for the first verification of the automated verification system for low-voltage current transformers for measurement or the acceptance verification before commissioning, it is still based on JJG 1139-2017 Automated Verification System for Low-voltage Current Transformers for Measurement.

[0092] The online calibration method of the low-voltage current transformer automatic verification system of the present invention has many advantages over the traditional traceability:

[0093] (1) When carrying out the value transfer work, it is not necessary to stop the automated verification system and remove the standard instrument. Long-term disassembly and installation of the standard instrument will cause the terminal to age and the measurement performance to be impaired;

[0094] (2) Online calibration with error measurement units as the whole can more truly reflect the metrological performance of the automated verification system under actual operating conditions, greatly reduce the traceability time of measurement values, and significantly improve quality and efficiency;

[0095] (3) We should thoroughly implement the requirements of the “Guiding Opinions on Strengthening the Construction of a National Modern Advanced Measurement System” to implement remote and online calibration of measuring equipment, break through online, dynamic, remote and rapid calibration technologies, and solve the problem of accurate measurement of extreme quantities, complex quantities, micro quantities, etc.

[0096] Embodiment 2:

[0097] The present invention also proposes an online calibration system 200 for a low voltage current transformer automatic verification system, such as Figure 3 As shown, including:

[0098] A calibration unit 201, configured to calibrate the current transformer under test based on the automated calibration system for the low-voltage current transformer under test;

[0099] Among them, a miniaturized standard current transformer is used as the current transformer to be tested and connected to the automatic verification system of the low-voltage current transformer to be tested;

[0100] The output unit 202 is used to read the calibration result of the current transformer under test;

[0101] The judgment unit 203 is used to convert the calibration result into the basic error of the automatic verification system of the low-voltage current transformer under test, and based on the basic error, calibrate whether the measurement performance of the error measurement unit of the automatic verification system of the low-voltage current transformer under test is qualified.

[0102] The test results include: the ratio difference and phase difference measured by the basic error measurement unit of the automated test system for the low-voltage current transformer under test, and the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measurement points.

[0103] Among them, the basic error includes: the ratio difference and phase difference of the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test.

[0104] Among them, based on the following conversion, the verification result is converted into the basic error of the automatic verification system of the low-voltage current transformer under test. The conversion formula is as follows:

[0105] f x =-f0+f p

[0106] δ x =-δ0+δ p

[0107] Among them, f x and δ x f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively. f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively. p and δ p They are the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measuring points.

[0108] Among them, if the miniaturized standard current transformer is two or more accuracy levels higher than the low-voltage current transformer automated verification system being measured, the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measuring point are not taken into account. Therefore, the conversion formula is as follows:

[0109] f x =-f0

[0110] δ x =-δ0

[0111] Among them, f x and δ x are the ratio difference and phase difference of the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively; f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively.

[0112] Wherein, based on the standard current transformer basic error limit table, according to the basic error, the automatic verification system of the low-voltage current transformer under test is calibrated to determine whether it is qualified.

[0113] The present invention can complete calibration without disassembling the system, and through online calibration, the workload is small, the verification efficiency is high, and system problems caused by disassembly are avoided.

[0114] Embodiment 3:

[0115] Based on the same inventive concept, the present invention also provides a computer device, which includes a processor and a memory, wherein the memory is used to store a computer program, the computer program includes program instructions, and the processor is used to execute the program instructions stored in the computer storage medium. The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, which is suitable for implementing one or more instructions, and is specifically suitable for loading and executing one or more instructions in the computer storage medium to implement the corresponding method flow or corresponding functions, so as to implement the steps of the method in the above embodiment.

[0116] Embodiment 4:

[0117] Based on the same inventive concept, the present invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device for storing programs and data. It is understandable that the computer-readable storage medium here can include both a built-in storage medium in a computer device and an extended storage medium supported by the computer device. The computer-readable storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by a processor are also stored in the storage space, and these instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the steps of the method in the above embodiment.

[0118] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes. The schemes in the embodiments of the present invention may be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0119] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0120] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0121] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0122] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0123] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. An online calibration method for a low voltage current transformer automatic verification system, characterized in that: The method comprises: A miniaturized standard current transformer is used as a current transformer to be tested, and is put online to an automated verification system for a low-voltage current transformer to be tested, and the current transformer to be tested is calibrated based on the automated verification system for the low-voltage current transformer to be tested; Read the calibration result of the current transformer under test; The calibration result is converted into a basic error of the automated verification system for the low-voltage current transformer under test, and based on the basic error, the measurement performance of the error measurement unit of the automated verification system for the low-voltage current transformer under test is calibrated to determine whether it is qualified.

2. The method according to claim 1, characterized in that The calibration result includes: the ratio difference and phase difference measured by the basic error measurement unit of the automated verification system of the low-voltage current transformer under test, and the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measurement points.

3. The method according to claim 1, characterized in that The basic error includes: the ratio difference and phase difference of the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test.

4. The method according to claim 1, characterized in that: Based on the following conversion, the test result is converted into the basic error of the automatic test system of the low-voltage current transformer under test. The conversion formula is as follows: f x =-f0+f p d x =-δ0+δ p Among them, f x and δ x f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively. f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively. p and δ p They are the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measuring points.

5. The method according to claim 4, characterized in that If the miniaturized standard current transformer is two or more accuracy levels higher than the low-voltage current transformer automated verification system being tested, the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measuring point are not taken into account. Therefore, the conversion formula is as follows: f x =-f0 d x =-δ0 Among them, f x and δ x are the ratio difference and phase difference of the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively; f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively.

6. The method according to claim 1, characterized in that Based on the standard current transformer basic error limit table, according to the basic error, calibrate whether the low-voltage current transformer automatic verification system under test is qualified.

7. An online calibration system for a low voltage current transformer automatic verification system, characterized in that: The system comprises: A calibration unit, used for calibrating the current transformer under test based on the automatic calibration system of the low-voltage current transformer under test; Among them, a miniaturized standard current transformer is used as the current transformer to be tested and connected to the automatic verification system of the low-voltage current transformer to be tested; An output unit, used for reading the calibration result of the current transformer under test; The judgment unit is used to convert the calibration result into the basic error of the automatic verification system of the low-voltage current transformer under test, and based on the basic error, calibrate whether the measurement performance of the error measurement unit of the automatic verification system of the low-voltage current transformer under test is qualified.

8. The system according to claim 7, characterized in that The calibration result includes: the ratio difference and phase difference measured by the basic error measurement unit of the automated verification system of the low-voltage current transformer under test, and the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measurement points.

9. The system according to claim 7, characterized in that The basic error includes: the ratio difference and phase difference of the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test.

10. The system according to claim 7, characterized in that Based on the following conversion, the test result is converted into the basic error of the automatic test system of the low-voltage current transformer under test. The conversion formula is as follows: f x =-f0+f p d x =-δ0+δ p Among them, f x and δ x f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively. f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively. p and δ p They are the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measuring points.

11. The system according to claim 10, characterized in that If the miniaturized standard current transformer is two or more accuracy levels higher than the low-voltage current transformer automated verification system being tested, the ratio difference and phase difference of the miniaturized standard current transformer at the corresponding measuring point are not taken into account. Therefore, the conversion formula is as follows: f x =-f0 d x =-δ0 Among them, f x and δ x are the ratio difference and phase difference of the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively; f0 and δ0 are the ratio difference and phase difference measured by the basic error measurement unit of the automatic verification system of the low-voltage current transformer under test, respectively.

12. The system according to claim 7, characterized in that Based on the standard current transformer basic error limit table, according to the basic error, calibrate whether the low-voltage current transformer automatic verification system under test is qualified.

13. A computer device, characterized in that: include: one or more processors; a processor for executing one or more programs; When the one or more programs are executed by the one or more processors, the method according to any one of claims 1 to 6 is implemented.

14. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed, the method according to any one of claims 1 to 6 is implemented.

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