CN107861091B - Dynamic performance tracing method based on dynamic electric energy calibrator - Google Patents
Dynamic performance tracing method based on dynamic electric energy calibrator Download PDFInfo
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- CN107861091B CN107861091B CN201710990020.1A CN201710990020A CN107861091B CN 107861091 B CN107861091 B CN 107861091B CN 201710990020 A CN201710990020 A CN 201710990020A CN 107861091 B CN107861091 B CN 107861091B
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- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R35/00—Testing or calibrating of apparatus covered by the other groups of this subclass
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Abstract
a dynamic performance tracing method based on a dynamic electric energy calibrator comprises the steps of (1) selecting a standard device with the accuracy grade of 0.01 under a steady-state test signal; (2) selecting a standard meter with 0.05-level high dynamic performance as a 0.05-level dynamic electric energy calibrator; (3) under the condition of a steady-state test signal, the 0.01-level standard device is used for carrying out conventional calibration on the 0.05-level dynamic electric energy calibrator; (4) selecting a device for measuring the dynamic performance of the electric energy meter of 0.1 grade and below grade which needs to be calibrated; (5) under the condition of a dynamic test signal, calibrating the accuracy index of the dynamic performance of the electric energy meter dynamic performance measuring device of the level 0.1 and the level below by using a 0.05-level dynamic electric energy calibrator through electric energy comparison; (6) and under the condition of a dynamic test signal, the dynamic performance indexes of the tested electric energy meter are examined by the electric energy meter dynamic performance measuring device with the level of 0.1 and below after calibration.
Description
Technical Field
The invention relates to a dynamic performance tracing method based on a dynamic electric energy calibrator, and belongs to the technical field of electric energy metering.
Background
Under the existing electric energy value traceability system, the verification and verification of the electric energy meter all adopt steady-state signals as test signals, although a verification regulation stipulates a plurality of current and power factor test points, the error indexes of all the test points are measured after the voltage and current signals reach a set value and are stable, and the verification result only reflects the steady-state performance indexes of the electric energy meter. In order to ensure that the electric energy meter can accurately measure under the dynamic signal environment of some nonlinear loads, an electric energy meter dynamic performance measuring device needs to be developed and adopted to check the dynamic performance indexes of the electric energy meter, and the tracing of the measuring device is needed to be realized in order to ensure the use accuracy and the compliance of the measuring device.
at present, the tracing method for dynamic performance at home and abroad mainly comprises the following two methods: firstly, a learner provides a method for measuring dynamic errors of an electric energy meter, a sinusoidal envelope power frequency signal and a trapezoidal envelope power frequency signal are used as dynamic conditions, the characteristics of the existing standard power (electric energy) meter under the dynamic conditions are inspected by a method of source meter combination and multi-parameter and multi-instrument measurement mutual check, and uncertainty estimation of 3.0% is preliminarily obtained; secondly, a scholars comprehensively obtains 0.4778% standard uncertainty by considering standard uncertainty introduced by measurement repeatability, standard uncertainty introduced by errors of an electric energy meter calibration device, standard uncertainty introduced by superior transfer errors of the electric energy meter calibration device, standard uncertainty introduced by errors of the electric energy meter dynamic error testing device and standard uncertainty introduced by errors generated by an electric energy meter dynamic error theoretical calculation method through a test result of an electric energy meter dynamic error testing device developed based on an amplitude shift keying (ASK modulation) signal modulation mechanism.
Therefore, the existing dynamic performance traceability precision further improves the space, and the invention provides a dynamic performance traceability method, which can realize the traceability of a 0.1-level electric energy meter dynamic performance measuring device by adopting a dynamic electric energy calibrator.
Disclosure of Invention
The purpose of the invention is: the invention provides a dynamic performance traceability method based on a dynamic electric energy calibrator, which aims to solve the traceability problem of electric energy metering under the condition of dynamic load, is suitable for testing and evaluating the metering performance of an electric energy meter under various dynamic loads and developing corresponding testing devices.
in order to achieve the above object, the present invention provides a dynamic performance tracing method based on a dynamic electric energy calibrator, wherein the dynamic electric energy calibrator calibrates an accuracy index of a dynamic performance measuring device of an electric energy meter by comparing electric energy under a dynamic test signal condition, and compares the accuracy index of the dynamic performance measuring device of the electric energy meter with the accuracy index of the dynamic performance measuring device of the electric energy meter under the dynamic test signal condition to calibrate the dynamic performance measuring device of the electric energy meter, so that the dynamic performance tracing method is performed under the dynamic test signal condition, and the method comprises:
(1) selecting a standard device with the accuracy grade of 0.01 grade under a steady-state test signal;
(2) Selecting a standard meter with 0.05-level high dynamic performance as a 0.05-level dynamic electric energy calibrator;
(3) under the condition of a steady-state test signal, the 0.01-level standard device is used for carrying out conventional calibration on the 0.05-level dynamic electric energy calibrator, and the 0.05-level dynamic electric energy calibrator is confirmed to meet the requirement of a steady-state index;
(4) selecting a device for measuring the dynamic performance of the electric energy meter of 0.1 grade and below grade which needs to be calibrated;
(5) Under the condition of a dynamic test signal, calibrating the accuracy indexes of the dynamic performance of the electric energy meter dynamic performance measuring device of the 0.1 level and the lower level by using a 0.05 level dynamic electric energy calibrator through electric energy comparison;
(6) Under the condition of dynamic test signals, the electric energy meter dynamic performance measuring device with the level of 0.1 and below after calibration can be used for checking the dynamic performance indexes of the tested electric energy meter.
Wherein, in the step (2), the requirement for selecting the 0.05-stage dynamic power calibrator is as follows: selecting a standard table with high dynamic performance, and under a steady-state test signal, performing conventional calibration on a 0.01-level standard device; under the condition of dynamic test signals, the 0.05-level dynamic electric energy calibrator needs to overcome the influence of factors such as range switching, sampling synchronization errors, phase compensation and the like on the dynamic performance of the electric energy meter, and adopts the method of generating electric energy pulses according to instantaneous power calculation, so that the change of the test signals can be reflected in time, and the accuracy of dynamic electric energy measurement is high.
In step (3), under the condition of a steady-state test signal, the 0.01-level standard device is used for carrying out conventional calibration on the 0.05-level dynamic power calibrator, and the time requirements of the calibration are as follows: the standard device of the 0.01 level generates electric energy pulses based on average power calculation, the dynamic calibrator of the 0.05 level generates electric energy pulses based on instantaneous power calculation, in order to overcome the influence of the difference of the output modes of the two electric energy pulses on the measurement result to a degree of being basically ignored, the calibration time for obtaining each error result is required to be not less than the power factor under the rated voltage current, and Emax is the maximum value accepted by the additional error caused by the difference of the output pulse modes of the two electric energy pulses.
A dynamic performance traceability system based on a dynamic electric energy calibrator comprises a 0.01-level standard device, a 0.05-level dynamic electric energy calibrator, a 0.01-level and lower-level electric energy meter dynamic performance testing device, a tested electric energy meter, a steady-state testing signal source and a dynamic testing signal source; the steady-state test signal source sends steady-state test signals to the 0.01-level standard device and the 0.05-level dynamic electric energy calibrator respectively, and the 0.01-level standard device performs conventional calibration on the 0.05-level dynamic electric energy calibrator under the condition of the steady-state test signals; the dynamic test signal source sends dynamic test signals to a 0.05-level dynamic electric energy calibrator, a 0.1-level electric energy meter dynamic performance test device and a lower-level electric energy meter dynamic performance test device respectively, and under the condition of the dynamic test signals, the 0.05-level dynamic electric energy calibrator calibrates the dynamic performance accuracy indexes of the 0.01-level electric energy meter dynamic performance test device and the lower-level electric energy meter dynamic performance test device; similarly, the calibrated dynamic performance measuring device of the electric energy meter with the grade of 0.01 and below can be used for checking the dynamic performance index of the tested electric energy meter under the condition of a dynamic test signal.
Compared with the prior art, the invention has the beneficial effects that: the dynamic performance tracing method based on the dynamic calibrator, provided by the invention, can solve the problem of tracing of electric energy metering under the condition of dynamic loads, ensure the use accuracy and compliance of the measuring device, realize the tracing of the measuring device, and then be used for effectively testing and evaluating the metering performance of the electric energy meter under various dynamic loads.
Drawings
FIG. 1 is a flow chart of dynamic performance tracing based on a dynamic power calibrator;
Fig. 2 is a schematic diagram of a dynamic performance traceability system based on a dynamic power calibrator.
Detailed Description
The specific embodiments of the invention are shown in the attached drawings.
Tracing the electric energy meter measuring device, and directly measuring the accuracy index of the device by adopting a device calibrating instrument or a standard meter with higher precision than the device. The embodiment continues to use the tracing thought to develop a standard meter with high dynamic performance, overcomes the influence of factors such as range switching, sampling synchronization error, phase compensation and the like on the dynamic performance of the electric energy meter, has high accuracy of electric energy measurement in a dynamic signal environment, and provides a dynamic performance tracing method taking the standard meter with high dynamic performance as a dynamic electric energy calibrator.
in verification and calibration, a steady-state signal is used as a test signal, the error index of each test point is measured after the voltage and current signal reaches a set value and is stabilized, and a verification result only reflects the steady-state performance index and is called as conventional calibration; in the verification and verification, a dynamic signal is used as a test signal, the error index of each test point is measured under the dynamic condition that the voltage and current signals are rapidly changed in parameters such as amplitude, frequency, phase and the like, and the verification result can reflect the dynamic performance index and is called dynamic calibration.
fig. 1 is a flowchart of a dynamic performance tracing method according to this embodiment, which includes the following specific steps:
Step 1, selecting a standard device with the accuracy grade of 0.01 grade under a steady-state test signal;
Step 2, selecting a standard meter with 0.05-level high dynamic performance as a 0.05-level dynamic electric energy calibrator;
Step 3, under the condition of a steady-state test signal, the 0.01-level standard device is used for carrying out conventional calibration on the 0.05-level dynamic electric energy calibrator, and the 0.05-level dynamic electric energy calibrator is confirmed to meet the requirement of a steady-state index;
step 4, selecting a device for measuring the dynamic performance of the electric energy meter of 0.1 grade and below grade to be calibrated;
Step 5, calibrating the accuracy indexes of the dynamic performance of the electric energy meter dynamic performance measuring device of the level 0.1 and the level below by using a 0.05 level dynamic electric energy calibrator through electric energy comparison under the condition of dynamic test signals;
and 6, under the condition of dynamic test signals, the electric energy meter dynamic performance measuring device with the level of 0.1 and below after calibration can be used for checking the dynamic performance indexes of the tested electric energy meter.
in step 2 of this embodiment, the requirements for selecting the 0.05-stage dynamic power calibrator are as follows: selecting a standard table with high dynamic performance, and under a steady-state test signal, performing conventional calibration on a 0.01-level standard device; under the condition of dynamic test signals, the 0.05-level dynamic electric energy calibrator needs to overcome the influence of factors such as range switching, sampling synchronization errors, phase compensation and the like on the dynamic performance of the electric energy meter, and adopts the method of generating electric energy pulses according to instantaneous power calculation, so that the change of the test signals can be reflected in time, and the accuracy of dynamic electric energy measurement is high.
In step 3 of this embodiment, under the condition of a steady-state test signal, the 0.01-stage standard device is used to perform a conventional calibration on the 0.05-stage dynamic power calibrator, and the time requirements for the two calibrations are: the standard device of the 0.01 level generates electric energy pulses based on average power calculation, the dynamic calibrator of the 0.05 level generates electric energy pulses based on instantaneous power calculation, in order to overcome the influence of the difference of the output modes of the two electric energy pulses on the measurement result to a degree of being basically ignored, the calibration time for obtaining each error result is required to be not less than the power factor under the rated voltage current, and Emax is the maximum value accepted by the additional error caused by the difference of the output pulse modes of the two electric energy pulses. When t is 20 seconds and the power factor is 1, Emax is 0.0159%, 1/3 which is close to the maximum allowable error of 0.05%; the power factor is still 1, and t is 63.6 seconds to make Emax 0.005%.
FIG. 2 is a schematic diagram of the dynamic performance traceability system of the present invention.
The embodiment of the invention discloses a dynamic performance traceability system based on a dynamic electric energy calibrator, which comprises a 0.01-level standard device, a 0.05-level dynamic electric energy calibrator, a 0.01-level and lower-level electric energy meter dynamic performance testing device, a tested electric energy meter, a steady-state testing signal source and a dynamic testing signal source, wherein the dynamic testing signal source is connected with the tested electric energy meter; the steady-state test signal source sends steady-state test signals to the 0.01-level standard device and the 0.05-level dynamic electric energy calibrator respectively, and the 0.01-level standard device performs conventional calibration on the 0.05-level dynamic electric energy calibrator under the condition of the steady-state test signals; the dynamic test signal source sends dynamic test signals to a 0.05-level dynamic electric energy calibrator, a 0.1-level electric energy meter dynamic performance test device and a lower-level electric energy meter dynamic performance test device respectively, and under the condition of the dynamic test signals, the 0.05-level dynamic electric energy calibrator calibrates the dynamic performance accuracy indexes of the 0.01-level electric energy meter dynamic performance test device and the lower-level electric energy meter dynamic performance test device; similarly, the calibrated dynamic performance measuring device of the electric energy meter with the grade of 0.01 and below can be used for checking the dynamic performance index of the tested electric energy meter under the condition of a dynamic test signal.
as shown in fig. 2, the voltage and current signals output by the steady-state test signal source reach set values and are stable, and are respectively output to the 0.01-level standard device and the 0.05-level dynamic electric energy calibrator for conventional calibration, so that the calibration time for obtaining each error result is not less than 20 seconds, and the 0.05-level dynamic electric energy calibrator is ensured to meet the requirements of steady-state indexes; secondly, outputting dynamically changed voltage and current signals through a dynamic test signal source, and respectively outputting the dynamically changed voltage and current signals to a 0.05-level dynamic electric energy calibrator and a 0.1-level and lower-level electric energy meter dynamic performance measuring device for dynamic calibration, and calibrating whether the 0.1-level and lower-level electric energy meter dynamic performance measuring device meets the requirements of dynamic indexes; finally, a dynamically changed voltage and current signal is output through the dynamic test signal source and is respectively output to the dynamic performance measuring device of the electric energy meter with the level of 0.1 and below and the electric energy meter to be tested, and the dynamic performance measuring device is used for checking the dynamic performance index of the electric energy meter to be tested.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art; the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (3)
1. a dynamic performance tracing method based on a dynamic electric energy calibrator is characterized in that the dynamic electric energy calibrator calibrates accuracy indexes of dynamic performance measuring devices of electric energy meters through electric energy comparison under the condition of dynamic test signals, so that the measuring devices are calibrated, and tracing is performed under the dynamic test signals, and the method comprises the following steps:
(1) selecting a standard device with the accuracy grade of 0.01 grade under a steady-state test signal;
(2) selecting a standard meter with 0.05-level high dynamic performance as a 0.05-level dynamic electric energy calibrator;
(3) Under the condition of a steady-state test signal, the 0.01-level standard device is used for carrying out conventional calibration on the 0.05-level dynamic electric energy calibrator, and the 0.05-level dynamic electric energy calibrator is confirmed to meet the requirement of a steady-state index;
(4) selecting a device for measuring the dynamic performance of the electric energy meter of the grade below 0.1 to be calibrated;
(5) under the condition of a dynamic test signal, calibrating the accuracy index of the dynamic performance of the electric energy meter dynamic performance measuring device with the grade below 0.1 by using a 0.05-grade dynamic electric energy calibrator through electric energy comparison;
(6) and under the condition of a dynamic test signal, the dynamic performance indexes of the tested electric energy meter are examined by the electric energy meter dynamic performance measuring device with the level of 0.1 and below after calibration.
2. The dynamic performance tracing method based on dynamic power calibrator according to claim 1, wherein said requirement of 0.05 level dynamic power calibrator in step (2) is: selecting a standard table with high dynamic performance, and carrying out conventional calibration on a 0.01-level standard device under a steady-state test signal; under the condition of a dynamic test signal, the 0.05-level dynamic electric energy calibrator needs to overcome the influences of range switching, sampling synchronization errors and phase compensation factors on the dynamic performance of the electric energy meter, and generates electric energy pulses according to instantaneous power calculation.
3. The dynamic performance tracing method based on dynamic power calibrator according to claim 1, wherein in said step (3), under the condition of steady-state test signal, said 0.01-stage standard device performs regular calibration on said 0.05-stage dynamic power calibrator, and the time requirements for both verification are: at a rated voltage, the calibration time for obtaining each error result must not be less than the maximum value that can be accepted for the additional error caused by the difference of the output pulse modes of the two, wherein the calibration time is the power factor.
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| CN111190134B (en) * | 2019-12-26 | 2024-05-14 | 国网江西省电力有限公司电力科学研究院 | Dynamic response time characteristic test method and verification device for electric energy meter |
| CN112834973A (en) * | 2020-07-30 | 2021-05-25 | 中科知影(北京)科技有限公司 | Calibration system and method for magnetometers |
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