Overseas electric energy meter error single-point calibration method

Abstract

The invention discloses an overseas electric energy meter error single-point calibration method. Firstly, an overseas electric energy meter is connected to the output end of a standard table body; the single-point condition that Un = 230V, Ib = 5A and PF = 0.5 L is input into an operation interface at the front end of the upper computer to set the output of the standard table body, after the overseas electric energy meter is powered on, the active power and the reactive power output by the standard table body are obtained, the overseas electric energy meter is connected with the infrared photoelectric head, and the type of the electric energy meter is selected; the initial metering parameter key and the meter calibration parameter key are pressed, and the meter calibration operation can be completed when the complete meter calibration mark of the electric energy meter appears. A single-point condition calibration method with Un = 230V, Ib = 5A and PF = 0.5 L is adopted, and output values of a standard table body are unified and fixed, so that the difference between actual voltages and actual currents tested by different electric energy meters is small, the calculation time is saved, no matter how voltage and current specifications of the electric energy meters are, metering errors of calibration of the electric energy meters are not influenced, and the calibration efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electric energy meter calibration, and in particular to a single-point calibration method for overseas electric energy meter errors. Background Art

[0002] With the continuous development and growth of the overseas electric energy meter market, especially the impact on the power industry of African countries, various electric energy meters have been born and applied to the power grids of various countries. These electric energy meters include ordinary single-phase electric energy meters, ordinary three-phase electric energy meters, single-phase and three-phase high-voltage electric energy meters, single-phase and three-phase photovoltaic electric energy meters, rail meters and other series of products, up to dozens of types of electric energy meter products. The voltage and current specifications of electric energy meters used in each country are mostly different. Compared with domestic electric energy meters, the voltage specification type requirements of 220V are more complicated. Although the technology of electric energy metering overseas is very mature, the calibration method of electric energy metering error overseas still follows the previous method: according to the U of electric energy meters of different specifications, the calibration method of electric energy metering error is still the same as before: according to the U of electric energy meters of different specifications, the calibration method of electric energy metering error is still the same as before. n ,I b And manganese copper value (impedance property value of special material used for current sampling), and then compare the value of the standard meter to verify the measurement error. Therefore, to calibrate electric energy meters of different specifications, it is necessary to frequently modify the relevant program parameters of the electric energy meter, and double-point calibration is required, and the compatibility is poor.

[0003] Therefore, it is necessary to study an innovative single-point calibration method for overseas electricity meters to improve the efficiency of overseas electricity meters error calibration. Summary of the invention

[0004] The purpose of the present application is to provide a single-point calibration method for overseas electric energy meter errors, so as to solve the problem of low efficiency in calibrating electric energy meters using existing electric energy meter measurement error calibration methods.

[0005] In order to solve the above technical problems, the present application provides a single-point calibration method for overseas electric energy meter errors, including:

[0006] Connecting the overseas electric energy meter whose measurement error is to be calibrated to the output end of the standard platform to supply power to the overseas electric energy meter;

[0007] Enter the rated voltage U in the front-end operation interface of the host computer. n =230V, rated current I b =5A, power factor PF = 0.5L single point condition to set the output of the standard table, after the overseas electric energy meter is powered on, the active power P and reactive power Q output by the standard table are obtained, and the rated voltage U n , the rated current I b , the active power P and the reactive power Q are added to the front-end operation interface;

[0008] Connect the overseas electric energy meter to the infrared photoelectric head, and select the electric meter type corresponding to the overseas electric energy meter in the front-end operation interface;

[0009] Press the initialization metering parameter button and the calibration parameter button on the front-end operation interface, and the calibration operation is completed when the complete calibration mark of the electric energy meter appears.

[0010] As a preferred implementation, a single-point calibration method for overseas electric energy meters is provided, wherein the overseas electric energy meters include ordinary single-phase electric energy meters, ordinary three-phase electric energy meters, single-phase and three-phase high-voltage electric energy meters, and single-phase and three-phase photovoltaic electric energy meters.

[0011] As a preferred implementation, a method for single-point calibration of overseas electric energy meter errors is provided, wherein the overseas electric energy meter communicates with the host computer via a DL645 communication protocol.

[0012] As a preferred implementation, a method for single-point calibration of overseas electric energy meter errors is provided, wherein the overseas electric energy meter is connected to the host computer via RS232 or RJ45 communication.

[0013] Compared with the prior art, the present invention provides a single-point calibration method for overseas electric energy meter errors. First, the overseas electric energy meter to be calibrated for measurement error is connected to the output end of the standard platform to power the overseas electric energy meter; the rated voltage U is input in the front-end operation interface of the host computer. n =230V, rated current I b =5A, power factor PF = 0.5L single point condition to set the output of the standard unit, after the overseas energy meter is powered on, get the active power P and reactive power Q output by the standard unit, and set the rated voltage U n , Rated current I b , active power P and reactive power Q are added to the front-end operation interface; connect the overseas electric energy meter with the infrared photoelectric head, and select the electric energy meter type corresponding to the overseas electric energy meter in the front-end operation interface; press the initialization metering parameter button and the calibration parameter button on the front-end operation interface, and the calibration operation is completed when the electric energy meter is fully calibrated. n =230V, rated current I b =5A, power factor PF=0.5L single-point condition calibration method, the standard table output value is uniformly fixed, so that the actual voltage Ur and actual current Ir tested by different electric energy meters are less different, saving calculation time. No matter what voltage and current specifications of the electric energy meter that needs to be calibrated are, it will not affect the measurement error of the calibration electric energy meter, effectively improving the calibration efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solution of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without inventiveness.

[0015] Figure 1 A flow chart of a single-point calibration method for overseas electric energy meter errors provided in an embodiment of the present application;

[0016] Figure 2 A logic diagram for error calibration of a single three-phase electric energy meter provided in an embodiment of the present application. DETAILED DESCRIPTION

[0017] In order to enable those skilled in the art to better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings.

[0018] The core of this application is to provide a single-point calibration method for overseas electric energy meter errors, which solves the problem of low efficiency in calibrating electric energy meters using existing electric energy meter measurement error calibration methods.

[0019] In current technology, when calibrating the error of overseas electric energy meters, the rated voltage U of the electric energy meter is usually required. n and rated current I b Then the standard platform is based on the U n ,I b Set the standard table output to power the energy meter, and calibrate the voltage and current values ​​according to the energy meter measurement value and the standard table setting value so that:

[0020] U 表 =U 台 , I 表 =I 台 Then, according to the power method, the active power and reactive power of the electric energy meter under the conditions of PF = 1.0 and PF = 0.5L are calibrated so that: P 表 =P 台 , Q 表 =Q 台 , so as to achieve the purpose of calibrating the electric energy meter.

[0021] The above common method of calibrating the error of the electric energy meter needs to be based on the U n ,I b The power value under the conditions of PF=1.0 and PF=0.5L double-point calibration should be calibrated every time, and the U n ,I b The value needs to be modified and the calibration process is complicated and troublesome.

[0022] Figure 1A flow chart of a single-point calibration method for overseas electric energy meter errors provided in an embodiment of the present application. Figure 2 A logic diagram for error calibration of a single three-phase electric energy meter provided in an embodiment of the present application is shown in FIG. Figure 1 to Figure 2 shown.

[0023] A single-point calibration method for overseas electric energy meter errors comprises the following steps:

[0024] S1: Connect the overseas electric energy meter whose measurement error is to be calibrated to the output terminal of the standard table to supply power to the overseas electric energy meter;

[0025] S2: Enter the rated voltage U in the front-end operation interface of the host computer. n =230V, rated current I b =5A, power factor PF = 0.5L single point condition to set the output of the standard unit, after the overseas energy meter is powered on, get the active power P and reactive power Q output by the standard unit, and set the rated voltage U n , Rated current I b , active power P and reactive power Q are added to the front-end operation interface;

[0026] S3: Connect the overseas electric energy meter to the infrared photoelectric head, and select the meter type corresponding to the overseas electric energy meter in the front-end operation interface;

[0027] S4: Press the initialization metering parameter button and the calibration parameter button on the front-end operation interface. When the meter is fully calibrated, the calibration operation is completed. This calibration method is not restricted by the voltage and current specifications of different meters and meets the calibration requirements of meters of various specifications. It is applicable to meters on multiple platforms and is still applicable even if the microcontroller of the meter is replaced.

[0028] As a preferred implementation method, a single-point calibration method for overseas electric energy meters is provided, wherein the overseas electric energy meters include ordinary single-phase electric energy meters, ordinary three-phase electric energy meters, single-phase and three-phase high-voltage electric energy meters, and single-phase and three-phase photovoltaic electric energy meters.

[0029] As a preferred implementation, a method for single-point calibration of overseas electric energy meter errors is provided, wherein the overseas electric energy meter communicates with a host computer via a DL645 communication protocol.

[0030] As a preferred implementation, a method for single-point calibration of overseas electric energy meter errors is provided, wherein the overseas electric energy meter is connected to a host computer via RS232 or RJ45 communication.

[0031] The overseas electric energy meter error single-point calibration method provided in the embodiment of the present application is mainly supported by the following main logics:

[0032] 1. Logic of fixed basic parameters: No matter what voltage and current specifications the overseas electric energy meter that needs to be calibrated has, it will not affect the measurement error of the calibrated electric energy meter. During the calibration process, all meters are based on U n =230V, I b The meter is calibrated under the single-point condition of =5A, PF=0.5L. Under this condition, the active power P and reactive power Q output by the standard table are also fixed values. All electric energy meters are calibrated for measurement errors based on this standard value.

[0033] 2. Single-phase and three-phase compatible logic; such as Figure 2 As shown, no matter whether the required calibration error is single-phase or three-phase, the program implanted in the overseas electric energy meter uses the switch function, and uses the judgment condition to distinguish the single-phase and three-phase calibration, which can be compatible with the error calibration of two types of electric energy meters. Specifically, different judgment conditions and phase number combinations can meet the calibration requirements of single-phase and three-phase electric energy meters. One of the data 0, 1, 2, 3, and 5 is passed into the function, which means a calibration mode, which can complete the calibration of the live and neutral line measurement errors of the single-phase electric energy meter separately, and can complete the simultaneous calibration or phase-by-phase calibration of the A, B, C and neutral line measurement errors of the three-phase electric energy meter, and only needs to calibrate the PF=0.5L point, which has a high calibration efficiency.

[0034] The single-point calibration method for overseas electric energy meters is no longer based on the U of different meters. n and I b To set the output of the standard stage, instead of using a fixed value U n =230V, I b =5A can be set, the electric energy meter reads the actual voltage U according to the output of the standard table r and the actual current I r , the effective voltage values ​​measured by the voltage register and current register of the energy meter are DataU and DataI. According to the program implanted in the overseas energy meter, the error calibration can be performed according to the following logic:

[0035] Known:

[0036] Actual input voltage effective value U r , the actual input current is I r

[0037] Measured voltage RMS value U rms =DataU / 2^13

[0038] The measured current effective value I rms =(DataI / 2^13) / N(N=60 / I b )

[0039] Calculation formula:

[0040] U 误差=U r / U rms -1

[0041] I 误差 =I r / I rms -1

[0042] if:

[0043] U 误差 ≥0, then U 误差 =INT[U 误差 *2^15]

[0044] I 误差 ≥0, then I 误差 =INT[I 误差 *2^15]

[0045] if:

[0046] U 误差 <0, then U 误差 =INT[2^16+U 误差 *2^15]

[0047] I 误差 <0, then I 误差 =INT[2^16+I 误差 *2^15]

[0048] Therefore: 表 =U rms ±U 误差 , I 表 =I rms ±I 误差

[0049] According to the measured value of the electric energy meter and the setting value of the standard table, the voltage and current values ​​are calibrated so that:

[0050] U 表 =U r , I 表 =I r

[0051] According to the power method, the active power P of the electric energy meter under the condition of PF = 0.5L is calibrated

[0052]

[0053] It is known that the active power measured by the electric meter at PF = 0.5L is P 测

[0054] Error err% of the standard test

[0055]

[0056] If P 增益 ≥0, then P 误差 =INT[P 增益 *2^15]

[0057] If P 增益 <0, then P 误差 =INT[2^16+P 增益 *2^15]

[0058] When PF=0.5L:P 表 =P 测 ±P 误差

[0059] Finally, :P 表 =P 台 .

[0060] In this embodiment, the rated voltage U n =230V, rated current I b =5A, power factor PF=0.5L single-point condition calibration method, the standard table output value is uniformly fixed, so that the actual voltage Ur and actual current Ir tested by different electric energy meters are less different, saving calculation time. No matter what voltage and current specifications of the electric energy meter that needs to be calibrated are, it will not affect the measurement error of the calibration electric energy meter, effectively improving the calibration efficiency.

[0061] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the application disclosed herein. The present application is intended to cover any variations, uses or adaptations of the present application, which follow the general principles of the present application and include common knowledge or customary technical means in the art disclosed in the present application. The specification and examples are to be regarded as exemplary only, and the true scope of the present application is indicated by the claims.

[0062] It should be understood that the present application is not limited to the precise structure described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The above-described embodiments of the present application do not constitute a limitation on the scope of protection of the present application.

Claims

1. A single-point calibration method for overseas electric energy meter errors, characterized in that: include: Connecting the overseas electric energy meter whose measurement error is to be calibrated to the output end of the standard platform to supply power to the overseas electric energy meter; Enter the rated voltage U in the front-end operation interface of the host computer. n =230V, rated current I b =5A, power factor PF = 0.5L single point condition to set the output of the standard table, after the overseas electric energy meter is powered on, the active power P and reactive power Q output by the standard table are obtained, and the rated voltage U n , the rated current I b , the active power P and the reactive power Q are added to the front-end operation interface; Connect the overseas electric energy meter to the infrared photoelectric head, and select the electric meter type corresponding to the overseas electric energy meter in the front-end operation interface; Press the initialization metering parameter button and the calibration parameter button on the front-end operation interface, and the calibration operation is completed when the complete calibration mark of the electric energy meter appears.

2. The single-point calibration method for overseas electric energy meter errors according to claim 1 is characterized in that: The overseas electricity meters include ordinary single-phase electricity meters, ordinary three-phase electricity meters, single-phase and three-phase high-voltage electricity meters, and single-phase and three-phase photovoltaic electricity meters.

3. The single-point error calibration method for overseas electric energy meters according to claim 1 is characterized in that: The overseas electric energy meter communicates with the host computer via the DL645 communication protocol.

4. The overseas electric energy meter error single-point calibration method according to claim 1 is characterized in that: The overseas electric energy meter is connected to the host computer via RS232 or RJ45 communication.

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