A calibration system and method for electronic transformer tester

Abstract

The present invention discloses a calibration system and method for an electronic transformer calibrator, belonging to the field of intelligent device technology. The method of the present invention comprises: a clock reference module, a quantum voltage reference module, a standard signal source module, an inductive voltage divider module, a standard CT module and a standard sampling resistor module, a frequency division module, a differential sampling module, a reconstruction frame module, and a calibrator. The present invention applies a quantum voltage reference to the calibration of an electronic transformer calibrator, realizes high-precision sampling of analog quantities based on quantum voltage reference and differential sampling technology, and improves the uncertainty level of digital quantity signals. Compared with the traditional electronic transformer calibrator calibration device, the present invention improves the overall accuracy of the entire calibration system by tracing the digital quantity to the quantum voltage reference. In addition, the value of the electronic transformer calibrator calibration device is traced to the quantum reference, and the flat traceability of the value can be realized.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent devices, and more specifically, to a calibration system and method for an electronic transformer tester. Background Art

[0002] As an error measurement device for electronic transformers, the electronic transformer tester has analog signals and digital signals of IEC 61850 protocol as the output types of electronic transformers. Therefore, the measured input channels of the electronic transformer tester are divided into analog channels and digital message channels. The calibration of the electronic transformer tester is also divided into two forms: analog calibration and digital calibration of the electronic transformer tester. At present, the accuracy of the electronic transformer tester is generally 0.05%, while the accuracy of the electronic transformer tester calibration device is generally 0.02%, and the highest accuracy can reach 0.01%. The electronic transformer tester calibration device usually includes an industrial frequency proportional power supply, a voltage or current converter, a high-precision digital multimeter and a digital message generator. In order to realize the digital quantity calibration of the electronic transformer tester, the electronic transformer tester calibration device usually uses a high-precision digital multimeter as the A / D sampling module to directly sample the AC signal output by the industrial frequency proportional power supply, and then the digital message generator usually frames the sampled value into a digital message of the IEC 61850 protocol and sends it to the digital message channel of the electronic transformer tester. Since the digital multimeter is affected by the laboratory operating environment and the performance of the instrument itself during use, its actual measurement accuracy is generally around 0.01%, which limits the overall accuracy of the electronic transformer tester calibration device. In addition, this calibration method traces the value of the digital message to a high-precision digital multimeter, and then traces it to a calibration source with higher accuracy through the digital multimeter, using a step-by-step physical quantity transmission method. With the development of quantization technology and the emergence of quantum voltage standards, the flattened quantum quantity transmission method has significant advantages. The voltage quantity is directly traced to the quantum voltage standard, and the traditional gradual quantity transmission is no longer required, which improves the accuracy and reliability of quantity transmission and traceability.

[0003] In terms of electronic transformer calibration technology, the invention patent applied by Shanghai Institute of Metrology and Testing Technology - Inspection system and inspection method of electronic transformer calibrator (patent number: 201910975186.5) uses industrial frequency proportional power supply, high-precision digital multimeter and protocol conversion to realize analog and digital calibration of electronic transformer calibrator. In terms of quantized quantity transmission and traceability technology, the invention patent applied by China National Institute of Metrology - a quantum voltage-based AC voltage commutation differential measurement device and method (patent number: 201910203056.X) uses a commutation switch and a differential sampling circuit to perform differential sampling on the measured AC voltage and quantum voltage respectively, and uses the differential signal and quantum voltage to reconstruct the measured voltage, thereby improving the accuracy of AC voltage amplitude measurement. The invention patent applied for by the China National Institute of Metrology - an AC power differential measurement system and method based on quantum technology (patent number: 201611202556.4) uses two sampling units to sample the sinusoidal voltage and the AC quantum voltage respectively and calculate the phase difference, and adjusts the phase of the AC quantum voltage according to the phase difference, so that the step center positions of the sinusoidal voltage and the AC quantum voltage intersect, thereby improving the accuracy of AC signal measurement. Summary of the invention

[0004] In view of the above problems, the present invention proposes a calibration system for an electronic transformer tester, comprising:

[0005] A clock reference module, wherein the clock reference module provides a reference clock for the system;

[0006] A quantum voltage reference module, which receives a reference clock provided by the clock reference module and generates a synchronization pulse of a preset frequency and an AC quantum voltage step signal;

[0007] A standard signal source module, which receives the synchronization pulse output by the quantum voltage reference module and outputs an AC signal in phase-locked fashion with respect to the rising edge of the synchronization pulse;

[0008] An inductive voltage divider module, a standard CT module and a standard sampling resistor module, wherein the inductive voltage divider module, the standard CT module and the standard sampling resistor module receive the AC signal output by the standard signal source module, convert the AC signal with a preset proportional coefficient, and output an AC signal with an amplitude close to that of the quantum reference signal;

[0009] A frequency division module, which receives a synchronization pulse and performs frequency division processing on the synchronization pulse to output a synchronization pulse signal of a preset multiple of a preset frequency;

[0010] The synchronous pulse signal is a synchronous trigger signal of the differential sampling module and the electronic transformer tester;

[0011] A differential sampling module, wherein the differential sampling module is triggered by a synchronous trigger signal to perform differential sampling on an AC signal and a quantum reference signal to obtain a differential sampling value;

[0012] A reconstruction framing module, wherein the reconstruction framing module obtains the differential sampling value output by the differential sampling module, superimposes the sampling value with the amplitude of the AC quantum voltage step signal, generates the sampling value of the AC signal through reconstruction, converts the sampling value with a preset conversion coefficient, obtains a discrete AC signal, superimposes the discrete AC signal with a differential signal, outputs an AC sampling signal, frames the AC sampling signal into a digital message in a preset message format, and transmits it to the calibrator;

[0013] The calibrator receives digital messages, obtains signal errors, and completes the calibration of the voltage / current channel of the electronic transformer calibrator through the signal errors.

[0014] Optionally, the AC signal is converted with a preset proportionality factor, including:

[0015] If the AC signal is an AC voltage signal, the inductive voltage divider module converts the AC signal with a preset proportional coefficient and outputs an AC signal with an amplitude close to that of the quantum reference signal;

[0016] If the AC signal is an AC current signal, the standard CT module and the standard sampling resistor module convert the AC signal with a preset proportional coefficient and output an AC signal with an amplitude close to that of the quantum reference signal.

[0017] Optionally, the frequency of the reference clock is not less than 10 MHz.

[0018] Optionally, the quantum voltage reference module generates a synchronization pulse of not less than 50 Hz by a bias power supply, and the bias power supply drives an AC quantum voltage step signal with a frequency of not less than 50 Hz at the output end at the rising edge of the synchronization pulse of not less than 50 Hz, and each cycle of the AC quantum voltage step signal is composed of a plurality of DC voltage step signals of equal time periods, and the amplitude of the DC voltage signal of each step is controllable.

[0019] Optionally, reconstruct the framing module, including:

[0020] Reconstruction unit, differential unit and framing unit;

[0021] The reconstruction unit obtains the differential sampling value output by the differential sampling module, superimposes the sampling value with the amplitude of the AC quantum voltage step signal, generates the sampling value of the AC signal through reconstruction, and converts the sampling value with a preset conversion coefficient to obtain a discrete AC signal;

[0022] The differential unit superimposes the discrete AC signal with the differential signal to output an AC sampling signal;

[0023] The framing unit frames the AC sampling signal into a digital message in a preset message format and transmits the digital message to the calibration instrument.

[0024] The present invention also proposes a calibration method for an electronic transformer tester, comprising:

[0025] Control the clock reference module to provide a reference clock;

[0026] Control the quantum voltage reference module to receive the reference clock provided by the clock reference module, and generate a synchronization pulse of a preset frequency and an AC quantum voltage step signal;

[0027] The control standard signal source module receives the synchronization pulse output by the quantum voltage reference module, and outputs an AC signal in phase-locked manner according to the rising edge of the synchronization pulse;

[0028] Control the inductive voltage divider module, the standard CT module and the standard sampling resistor module to receive the AC signal output by the standard signal source module, convert the AC signal with a preset proportional coefficient, and output an AC signal with an amplitude close to that of the quantum reference signal;

[0029] The control frequency division module receives the synchronization pulse and performs frequency division processing on the synchronization pulse, and outputs a synchronization pulse signal of a preset multiple of a preset frequency;

[0030] Controlling the synchronous pulse signal to be a synchronous trigger signal of a differential sampling module and an electronic transformer tester;

[0031] Control the differential sampling module to trigger differential sampling of the AC signal and the quantum reference signal according to the synchronous trigger signal to obtain the differential sampling value;

[0032] Control the reconstruction frame module to obtain the differential sampling value output by the differential sampling module, superimpose the sampling value with the amplitude of the AC quantum voltage step signal, reconstruct and generate the sampling value of the AC signal, convert the sampling value with a preset conversion coefficient, obtain a discrete AC signal, superimpose the discrete AC signal with a differential signal, output an AC sampling signal, frame the AC sampling signal into a digital message in a preset message format, and transmit it to the calibrator;

[0033] The control calibrator receives digital messages, obtains signal errors, and completes the calibration of the voltage / current channel of the electronic transformer calibrator through the signal errors.

[0034] Optionally, the AC signal is converted with a preset proportionality factor, including:

[0035] If the AC signal is an AC voltage signal, the inductive voltage divider module is controlled to convert the AC signal with a preset proportional coefficient, and output an AC signal with an amplitude close to that of the quantum reference signal;

[0036] If the AC signal is an AC current signal, the standard CT module and the standard sampling resistor module are controlled to convert the AC signal with a preset proportional coefficient, and an AC signal with an amplitude close to that of the quantum reference signal is output.

[0037] Optionally, the frequency of the reference clock is not less than 10 MHz.

[0038] Optionally, the quantum voltage reference module generates a synchronization pulse of not less than 50 Hz by a bias power supply, and the bias power supply drives an AC quantum voltage step signal with a frequency of not less than 50 Hz at the output end at the rising edge of the synchronization pulse of not less than 50 Hz, and each cycle of the AC quantum voltage step signal is composed of a plurality of DC voltage step signals of equal time periods, and the amplitude of the DC voltage signal of each step is controllable.

[0039] The present invention applies a quantum voltage reference to the calibration of an electronic transformer calibrator, implements high-precision sampling of analog quantities based on the quantum voltage reference and differential sampling technology, and improves the uncertainty level of digital quantity signals. Compared with traditional electronic transformer calibrator calibration devices, the present invention improves the overall accuracy of the entire calibration system by tracing the digital quantity to the quantum voltage reference. In addition, by tracing the value of the electronic transformer calibrator calibration device to the quantum reference, flat traceability of the value can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A structural diagram of a calibration system for an electronic transformer tester according to the present invention;

[0041] Figure 2 It is a diagram of AC quantum voltage step signal and AC voltage signal of a calibration system for an electronic transformer tester of the present invention;

[0042] Figure 3 The present invention is a flow chart of a calibration method for an electronic transformer tester. DETAILED DESCRIPTION

[0043] 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.

[0044] 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.

[0045] In view of the above problems, the present invention proposes a calibration system for an electronic transformer tester, such as Figure 1 As shown, including:

[0046] A clock reference module, wherein the clock reference module provides a reference clock for the system;

[0047] A quantum voltage reference module, which receives a reference clock provided by the clock reference module and generates a synchronization pulse of a preset frequency and an AC quantum voltage step signal;

[0048] A standard signal source module, which receives the synchronization pulse output by the quantum voltage reference module and outputs an AC signal in phase-locked fashion with respect to the rising edge of the synchronization pulse;

[0049] An inductive voltage divider module, a standard CT module and a standard sampling resistor module, wherein the inductive voltage divider module, the standard CT module and the standard sampling resistor module receive the AC signal output by the standard signal source module, convert the AC signal with a preset proportional coefficient, and output an AC signal with an amplitude close to that of the quantum reference signal;

[0050] A frequency division module, which receives a synchronization pulse and performs frequency division processing on the synchronization pulse to output a synchronization pulse signal of a preset multiple of a preset frequency;

[0051] The synchronous pulse signal is a synchronous trigger signal of the differential sampling module and the electronic transformer tester;

[0052] A differential sampling module, wherein the differential sampling module is triggered by a synchronous trigger signal to perform differential sampling on an AC signal and a quantum reference signal to obtain a differential sampling value;

[0053] A reconstruction framing module, wherein the reconstruction framing module obtains the differential sampling value output by the differential sampling module, superimposes the sampling value with the amplitude of the AC quantum voltage step signal, generates the sampling value of the AC signal through reconstruction, converts the sampling value with a preset conversion coefficient, obtains a discrete AC signal, superimposes the discrete AC signal with a differential signal, outputs an AC sampling signal, frames the AC sampling signal into a digital message in a preset message format, and transmits it to the calibrator;

[0054] The calibrator receives digital messages, obtains signal errors, and completes the calibration of the voltage / current channel of the electronic transformer calibrator through the signal errors.

[0055] Converts AC signals with preset scaling factors, including:

[0056] If the AC signal is an AC voltage signal, the inductive voltage divider module converts the AC signal with a preset proportional coefficient and outputs an AC signal with an amplitude close to that of the quantum reference signal;

[0057] If the AC signal is an AC current signal, the standard CT module and the standard sampling resistor module convert the AC signal with a preset proportional coefficient and output an AC signal with an amplitude close to that of the quantum reference signal.

[0058] The frequency of the reference clock is not less than 10MHz.

[0059] The quantum voltage reference module generates a synchronous pulse of not less than 50Hz by a bias power supply. The bias power supply drives an AC quantum voltage step signal with a frequency of not less than 50Hz at the output end at the rising edge of the synchronous pulse of not less than 50Hz. Each cycle of the AC quantum voltage step signal is composed of a plurality of DC voltage step signals of equal time periods, and the amplitude of the DC voltage signal of each step is controllable.

[0060] Reconstruct the framing module, including:

[0061] Reconstruction unit, differential unit and framing unit;

[0062] The reconstruction unit obtains the differential sampling value output by the differential sampling module, superimposes the sampling value with the amplitude of the AC quantum voltage step signal, generates the sampling value of the AC signal through reconstruction, and converts the sampling value with a preset conversion coefficient to obtain a discrete AC signal;

[0063] The differential unit superimposes the discrete AC signal with the differential signal to output an AC sampling signal;

[0064] The framing unit frames the AC sampling signal into a digital message in a preset message format and transmits the digital message to the calibration instrument.

[0065] The present invention is described in detail below in conjunction with embodiments:

[0066] The present invention is divided into a voltage mode and a current mode. The voltage mode is used to calibrate the voltage channel of the electronic transformer calibrator, and the current mode is used to calibrate the current channel of the electronic transformer calibrator.

[0067] In voltage mode, the system of the present invention includes: a clock reference module, a quantum voltage reference module, a standard signal source module, a differential sampling module, an inductive voltage divider module, a reconstruction frame module and a frequency division module;

[0068] In current mode, the system of the present invention includes: a clock reference module, a quantum voltage reference module, a standard signal source module, a differential sampling module, a standard CT module, a standard sampling resistance module, a reconstruction frame module and a frequency division module;

[0069] The clock reference can be an external component or an internal component of Quantum Voltage. Its main function is to provide a 10MHz reference clock for the calibration system.

[0070] The low-end LO of the quantum voltage reference is connected to the low end of the inductive voltage divider or the standard CT, and the high-end HI is connected to the high-end HI of the differential sampling module. Its main function is to receive the 10MHz reference clock of the external clock reference, generate a 50Hz synchronization pulse by the bias power supply, and output the standard signal source and frequency division module; the bias power supply drives the AC-PJVS to output an AC quantum voltage step signal with a frequency of 50Hz at the LO and HI ends at the rising edge of the 50Hz synchronization pulse. like Figure 2 As shown, each cycle of the AC quantum voltage step signal is composed of N DC voltage step signals of equal time periods, and the DC voltage amplitude of each step can be programmably controlled.

[0071] The standard signal source has a phase-locked input port, an AC voltage signal output port and an AC current signal output port. Its output port is connected to the input end of the inductive voltage divider and the reference voltage input end of the calibrator. The main function of the standard signal source is to phase-lock the output of the AC voltage signal or AC current signal at the rising edge of the 50Hz synchronous pulse at the input end.

[0072] The main function of the inductive voltage divider is to realize voltage proportional conversion. The voltage conversion coefficient is k1 = U a / U b , the AC voltage signal output by the standard signal source Converted into an AC voltage signal close to the AC-PJVS output signal in the quantum voltage reference like Figure 2 As shown, the function of the inductive voltage divider is also to electrically isolate the AC-PJVS from the standard signal source and the calibrator.

[0073] The main function of the standard CT and the standard sampling resistor R is to realize the current / voltage ratio conversion. The voltage conversion coefficient is k2=I a / U b , the AC current signal output by the standard signal source Converted into a small AC voltage signal close to the AC-PJVS output signal in the quantum voltage reference In addition, the function of the standard CT is to electrically isolate the AC-PJVS from the standard signal source and the calibrator.

[0074] The main function of the frequency division module is to receive a 50Hz synchronous pulse signal, and after 50 times frequency division processing, output a 1Hz synchronous pulse signal to provide a synchronous trigger signal to the differential sampling module and the calibrator.

[0075] The differential sampling module has a differential sampling input port, a sampling value communication interface and an external trigger port. Its main function is to detect the AC signal output by the inductive voltage divider. and AC-PJVS output AC signal Differential sampling is performed, and the sampling trigger signal is provided by the 1Hz synchronous pulse output by the frequency division module. By setting the sampling rate and trigger delay time of the differential sampling module, the sampling time is kept as close to the AC signal as possible. At the middle moment of each DC voltage step, the differential sampling module transmits the differential sampling value to the reconstruction frame module for processing.

[0076] The reconstruction frame module includes a reconstruction module, a differential module and a frame module. Its main function is to convert the differential sampling value of the differential sampling module into the AC-PJVS output signal in the quantum voltage reference. The amplitude of the DC voltage steps is superimposed and reconstructed into an AC signal The sampling value is multiplied by the conversion coefficient k1 to obtain a discrete AC signal That is, it outputs the signal as a standard signal source The equivalent sampling signal.

[0077] The differential module is used in the AC equivalent sampling signal Superimpose differential signal Output AC sampling signal in Contains ratio error and phase error.

[0078] The framing module reconstructs the AC signal with the differential signal from the differential module. The digital message is framed into SV digital message according to the IEC61850 protocol format and output to the digital message interface of the calibrator through optical fiber.

[0079] In voltage mode, the bias power supply inside the quantum voltage reference outputs a 50Hz synchronous pulse in phase with the 10MHz reference clock output by the clock reference to the phase-locked input of the standard signal source and the input of the frequency division module. The standard signal source phase-locks and outputs a 50Hz AC voltage signal at the rising edge of the 50Hz synchronous pulse. And output to the inductive voltage divider input and the reference voltage input of the calibrator. The inductive voltage divider converts the AC voltage signal Convert to AC voltage signal The bias power supply drives the AC programmable Josephson voltage reference chip (AC-PJVS) output and the AC voltage signal at the rising edge of the 50Hz synchronous pulse AC quantum voltage step signal with the same amplitude Short the output low end of the inductive voltage divider with the output low end of AC-PJVS, and the differential sampling module senses the AC signal output by the inductive voltage divider. and AC-PJVS output AC signal The differential signal is sampled and the differential sampling value is output to the reconstruction module. The frequency division module divides the 50Hz synchronization pulse into a 1Hz synchronization pulse to provide a trigger signal for the differential sampling module and the calibrator. The reconstruction module superimposes the differential sampling value with the quantum step voltage of AC-PJVS to reconstruct the AC signal. The sampling value is multiplied by the conversion coefficient k1 to obtain the AC signal The differential module is used in AC signal Superimposed Difference Output discrete AC signal Among them, ε includes ratio error and phase error. The framing module discretizes the AC signal The SV message is framed in the IEC61850 protocol format and then output to the digital message interface of the calibrator through optical fiber; the calibrator synchronously collects the AC voltage signal at the reference voltage input terminal under the 1Hz synchronization pulse and receive the SV message of the IEC61850 protocol of the digital message interface, and calculate the error You can use the formula Calculate the error of the calibrator and calibrate the electronic transformer calibrator.

[0080] The current mode is similar to the voltage mode. The difference is that the standard signal source outputs a 50Hz AC current signal in phase with the rising edge of the 50Hz synchronous pulse. The output is sent to the reference current input terminal of the standard CT and the calibrator. The standard CT and the standard sampling resistor R form a current / voltage conversion module to convert the AC current signal Convert to AC voltage signal The bias power supply drives the AC programmable Josephson voltage reference chip (AC-PJVS) output and the AC voltage signal at the rising edge of the 50Hz synchronous pulse AC quantum voltage step signal with the same amplitude Short the output low end of the standard CT with the output low end of the AC-PJVS, and the differential sampling module will sense the AC voltage signal. And AC voltage signal output by AC-PJVS The differential signal is sampled and the differential sampling value is output to the reconstruction module. The frequency division module divides the 50Hz synchronization pulse into a 1Hz synchronization pulse to provide a trigger signal for the differential sampling module and the calibrator. The reconstruction module superimposes the differential sampling value with the quantum step voltage of AC-PJVS to reconstruct the AC signal. The sampling value is multiplied by the conversion coefficient k2 to obtain the AC signal The differential module is used in AC signal Superimposed Difference Output discrete AC signal in Including ratio error and phase error, the framing module discretes the AC signal The SV message is framed in the IEC61850 protocol format and then output to the digital message interface of the calibrator through optical fiber; the calibrator synchronously collects the AC voltage signal at the reference voltage input terminal under the 1Hz synchronization pulse and receive the SV message of the IEC61850 protocol of the digital message interface, and calculate the error You can use the formula Calculate the error of the calibrator and calibrate the electronic transformer calibrator.

[0081] By controlling the phase of the AC quantum voltage, the AC voltage signal and AC quantum voltage signal The effective amplitude of the differential signal is minimized; the phase of the AC quantum voltage is controlled by controlling the amplitude of the quantum voltage step in each signal cycle; the AC quantum voltage step amplitude is set to n=0, 1, 2, ..., N-1, where n is the step number after the rising edge of the 50Hz synchronous pulse output by the bias power supply, and N is the number of steps per cycle of the AC quantum voltage.

[0082] In the SV message in the IEC61850 protocol format sent by the framing module, the rated phase delay is set to Where N is the number of steps per cycle of the AC quantum voltage.

[0083] The present invention also proposes a calibration method for an electronic transformer tester, such as Figure 3 As shown, including:

[0084] Control the clock reference module to provide a reference clock;

[0085] Control the quantum voltage reference module to receive the reference clock provided by the clock reference module, and generate a synchronization pulse of a preset frequency and an AC quantum voltage step signal;

[0086] The control standard signal source module receives the synchronization pulse output by the quantum voltage reference module, and outputs an AC signal in phase-locked manner according to the rising edge of the synchronization pulse;

[0087] Control the inductive voltage divider module, the standard CT module and the standard sampling resistor module to receive the AC signal output by the standard signal source module, convert the AC signal with a preset proportional coefficient, and output an AC signal with an amplitude close to that of the quantum reference signal;

[0088] The control frequency division module receives the synchronization pulse and performs frequency division processing on the synchronization pulse, and outputs a synchronization pulse signal of a preset multiple of a preset frequency;

[0089] Controlling the synchronous pulse signal to be a synchronous trigger signal of a differential sampling module and an electronic transformer tester;

[0090] Control the differential sampling module to trigger differential sampling of the AC signal and the quantum reference signal according to the synchronous trigger signal to obtain the differential sampling value;

[0091] Control the reconstruction frame module to obtain the differential sampling value output by the differential sampling module, superimpose the sampling value with the amplitude of the AC quantum voltage step signal, reconstruct and generate the sampling value of the AC signal, convert the sampling value with a preset conversion coefficient, obtain a discrete AC signal, superimpose the discrete AC signal with a differential signal, output an AC sampling signal, frame the AC sampling signal into a digital message in a preset message format, and transmit it to the calibrator;

[0092] The control calibrator receives digital messages, obtains signal errors, and completes the calibration of the voltage / current channel of the electronic transformer calibrator through the signal errors.

[0093] Converts AC signals with preset scaling factors, including:

[0094] If the AC signal is an AC voltage signal, the inductive voltage divider module is controlled to convert the AC signal with a preset proportional coefficient, and output an AC signal with an amplitude close to that of the quantum reference signal;

[0095] If the AC signal is an AC current signal, the standard CT module and the standard sampling resistor module are controlled to convert the AC signal with a preset proportional coefficient, and an AC signal with an amplitude close to that of the quantum reference signal is output.

[0096] The frequency of the reference clock is not less than 10MHz.

[0097] The quantum voltage reference module generates a synchronous pulse of not less than 50Hz by a bias power supply. The bias power supply drives an AC quantum voltage step signal with a frequency of not less than 50Hz at the output end at the rising edge of the synchronous pulse of not less than 50Hz. Each cycle of the AC quantum voltage step signal is composed of a plurality of DC voltage step signals of equal time periods, and the amplitude of the DC voltage signal of each step is controllable.

[0098] The present invention applies a quantum voltage reference to the calibration of an electronic transformer calibrator, implements high-precision sampling of analog quantities based on the quantum voltage reference and differential sampling technology, and improves the uncertainty level of digital quantity signals. Compared with traditional electronic transformer calibrator calibration devices, the present invention improves the overall accuracy of the entire calibration system by tracing the digital quantity to the quantum voltage reference. In addition, by tracing the value of the electronic transformer calibrator calibration device to the quantum reference, flat traceability of the value can be achieved.

[0099] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of complete hardware embodiments, complete software embodiments, or embodiments in combination with software and hardware. Moreover, the present application can adopt 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.) that contain computer-usable program code. The scheme in the embodiments of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0100] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes 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 generate 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.

[0101] 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.

[0102] 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 A step that specifies a function in one or more boxes.

[0103] Although the preferred embodiments of the present application 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 falling within the scope of the present application.

[0104] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A calibration system for an electronic transformer tester, the system comprising: A clock reference module, wherein the clock reference module provides a reference clock for the system; A quantum voltage reference module, which receives a reference clock provided by the clock reference module and generates a synchronization pulse of a preset frequency and an AC quantum voltage step signal; A standard signal source module, which receives the synchronization pulse output by the quantum voltage reference module and outputs an AC signal in phase-locked fashion with respect to the rising edge of the synchronization pulse; An inductive voltage divider module, a standard CT module and a standard sampling resistor module, wherein the inductive voltage divider module, the standard CT module and the standard sampling resistor module receive the AC signal output by the standard signal source module, convert the AC signal with a preset proportional coefficient, and output an AC signal with an amplitude close to that of the quantum reference signal; A frequency division module, which receives a synchronization pulse and performs frequency division processing on the synchronization pulse to output a synchronization pulse signal of a preset multiple of a preset frequency; The synchronous pulse signal is a synchronous trigger signal of the differential sampling module and the electronic transformer tester; A differential sampling module, wherein the differential sampling module is triggered by a synchronous trigger signal to perform differential sampling on an AC signal and a quantum reference signal to obtain a differential sampling value; A reconstruction framing module, wherein the reconstruction framing module obtains the differential sampling value output by the differential sampling module, superimposes the sampling value with the amplitude of the AC quantum voltage step signal, generates the sampling value of the AC signal through reconstruction, converts the sampling value with a preset conversion coefficient, obtains a discrete AC signal, superimposes the discrete AC signal with a differential signal, outputs an AC sampling signal, frames the AC sampling signal into a digital message in a preset message format, and transmits it to the calibrator; A calibrator, which receives digital messages, obtains signal errors, and calibrates the voltage / current channels of the electronic transformer calibrator through the signal errors; The converting of the AC signal with a preset proportionality coefficient includes: If the AC signal is an AC voltage signal, the inductive voltage divider module converts the AC signal with a preset proportional coefficient and outputs an AC signal with an amplitude close to that of the quantum reference signal; If the AC signal is an AC current signal, the standard CT module and the standard sampling resistor module convert the AC signal with a preset proportional coefficient and output an AC signal with an amplitude close to that of the quantum reference signal; The frequency of the reference clock is not less than 10 MHz; The quantum voltage reference module generates a synchronous pulse of not less than 50 Hz by a bias power supply. Driven by the rising edge of the synchronous pulse of not less than 50 Hz, the bias power supply outputs an AC quantum voltage step signal with a frequency of not less than 50 Hz at the output end. Each cycle of the AC quantum voltage step signal is composed of a plurality of DC voltage step signals of equal time periods, and the amplitude of the DC voltage signal of each step is controllable.

2. The system according to claim 1, wherein the reconstructing frame module comprises: Reconstruction unit, differential unit and framing unit; The reconstruction unit obtains the differential sampling value output by the differential sampling module, superimposes the sampling value with the amplitude of the AC quantum voltage step signal, generates the sampling value of the AC signal through reconstruction, and converts the sampling value with a preset conversion coefficient to obtain a discrete AC signal; The differential unit superimposes the discrete AC signal with the differential signal to output an AC sampling signal; The framing unit frames the AC sampling signal into a digital message in a preset message format and transmits the digital message to the calibration instrument.

3. A calibration method for an electronic transformer tester using any one of the systems described in claims 1-2, the method comprising: Control the clock reference module to provide a reference clock; Control the quantum voltage reference module to receive the reference clock provided by the clock reference module, and generate a synchronization pulse of a preset frequency and an AC quantum voltage step signal; The control standard signal source module receives the synchronization pulse output by the quantum voltage reference module, and outputs an AC signal in phase-locked manner according to the rising edge of the synchronization pulse; Control the inductive voltage divider module, the standard CT module and the standard sampling resistor module to receive the AC signal output by the standard signal source module, convert the AC signal with a preset proportional coefficient, and output an AC signal with an amplitude close to that of the quantum reference signal; The control frequency division module receives the synchronization pulse and performs frequency division processing on the synchronization pulse, and outputs a synchronization pulse signal of a preset multiple of a preset frequency; Controlling the synchronous pulse signal to be a synchronous trigger signal of a differential sampling module and an electronic transformer tester; Control the differential sampling module to trigger differential sampling of the AC signal and the quantum reference signal according to the synchronous trigger signal to obtain the differential sampling value; Control the reconstruction frame module to obtain the differential sampling value output by the differential sampling module, superimpose the sampling value with the amplitude of the AC quantum voltage step signal, reconstruct and generate the sampling value of the AC signal, convert the sampling value with a preset conversion coefficient, obtain a discrete AC signal, superimpose the discrete AC signal with a differential signal, output an AC sampling signal, frame the AC sampling signal into a digital message in a preset message format, and transmit it to the calibrator; The control calibrator receives digital messages, obtains signal errors, and completes the calibration of the voltage / current channel of the electronic transformer calibrator through the signal errors; The converting of the AC signal with a preset proportionality coefficient includes: If the AC signal is an AC voltage signal, the inductive voltage divider module is controlled to convert the AC signal with a preset proportional coefficient, and output an AC signal with an amplitude close to that of the quantum reference signal; If the AC signal is an AC current signal, the standard CT module and the standard sampling resistor module are controlled to convert the AC signal with a preset proportional coefficient, and an AC signal with an amplitude close to that of the quantum reference signal is output; The frequency of the reference clock is not less than 10 MHz; The quantum voltage reference module generates a synchronous pulse of not less than 50 Hz by a bias power supply. Driven by the rising edge of the synchronous pulse of not less than 50 Hz, the bias power supply outputs an AC quantum voltage step signal with a frequency of not less than 50 Hz at the output end. Each cycle of the AC quantum voltage step signal is composed of a plurality of DC voltage step signals of equal time periods, and the amplitude of the DC voltage signal of each step is controllable.

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