CN106443567B - Real load test system of electric energy meter - Google Patents
Real load test system of electric energy meter Download PDFInfo
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- CN106443567B CN106443567B CN201611094396.6A CN201611094396A CN106443567B CN 106443567 B CN106443567 B CN 106443567B CN 201611094396 A CN201611094396 A CN 201611094396A CN 106443567 B CN106443567 B CN 106443567B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R35/00—Testing or calibrating of apparatus covered by the other groups of this subclass
- G01R35/04—Testing or calibrating of apparatus covered by the other groups of this subclass of instruments for measuring time integral of power or current
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P90/00—Enabling technologies with a potential contribution to greenhouse gas [GHG] emissions mitigation
- Y02P90/02—Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]
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Abstract
The invention relates to a real load test system of an electric energy meter, which comprises an upper computer, wherein the upper computer is in bidirectional communication with a central control board, the central control board is respectively in bidirectional communication with a single-phase error test device for carrying out error test on a single-phase tested electric energy meter and a three-phase error test device for carrying out error test on a three-phase tested electric energy meter, and the central control board supplies power to the single-phase error test device and the three-phase error test device. The invention can simulate the real load of the site electricity consumption, and test the metering error of the ammeter under the actual electricity consumption condition; the invention can output the actual load curve of the operation of the ammeter, and help to know and master the operation metering condition of the ammeter more closely and accurately; under the condition of real load, the invention tests the power carrier communication capability of the detected electric energy meter through the external carrier meter controller, and can more truly reflect the environment of the user site.
Description
Technical Field
The invention relates to the technical field of electric energy testing, in particular to a real load testing system of an electric energy meter.
Background
At present, intelligent electric energy meters are widely used, the electric energy meters are used as metering products with higher precision, and the metering accuracy and stability are important aspects of user attention. Before the electric energy meter leaves the factory, the electric energy meter manufacturer needs to measure the electric energy meter and verify the performance qualification, and judges whether the electric energy meter meets the requirements of users, whether the measurement precision and the performance quality are qualified or not, and whether the electric energy meter has the leaving-factory conditions or not.
Before the electric energy meter is formally put into use, the electric energy meter is approved by a verification of an electric power metering department, and the electric energy meter is required to detect the metering precision and verify the functional compliance. However, considering production cost and inspection cost, the calibrating devices used by manufacturers and electric power metering bureaus at present use dummy loads to calibrate the metering accuracy of the electric energy meter, namely a constant-output voltage current source is installed in the inspection bench, when the electric energy meter is tested, a constant-current voltage source is output to a sampling loop, the metering value flowing through the electric energy meter is obtained through conversion of an internal metering unit of the electric energy meter, then the metering value is compared with the metering value of a standard meter in the bench body, an error value of the electric energy meter to be calibrated is obtained, whether the error value meets the deviation requirement is compared, and whether the electric energy meter is qualified is judged. The method only judges the accuracy of the electric energy meter in theory, and the applied current is an ideal clean current and is not a load current in actual work. The working characteristics under the false load are not necessarily completely consistent with those under the real load, certain deviation can exist in metering errors, and the sampling verification is carried out on the electric energy meter under the real load in a more reliable way.
Disclosure of Invention
The invention aims to provide a real load test system of an electric energy meter, which adopts a real load to detect the metering function of a sampling circuit of the electric energy meter and judges whether the metering function of the electric energy meter is normal or not under the condition of simulating the actual electricity consumption of a user on site.
In order to achieve the above purpose, the present invention adopts the following technical scheme: the utility model provides a real load test system of electric energy meter, includes the host computer, host computer and the two-way communication of central control panel, the central control panel respectively with be used for carrying out the single-phase error testing arrangement of error test to single-phase electric energy meter to be examined, be used for carrying out the three-phase error testing arrangement two-way communication of error test to the three-phase electric energy meter to be examined, the central control panel is to single-phase error testing arrangement and three-phase error testing arrangement power supply respectively.
The central control board adopts a main control chip, and the main control chip is an STC89C516 main control chip.
The single-phase error testing device comprises a program-controlled single-phase power source, a first RLC load box, a first high-power voltage regulating source, a first standard electric energy meter, a first error calculator and a plurality of first error displays, wherein a first communication port of a central control board is connected with a communication control end of the program-controlled single-phase power source, the program-controlled single-phase power source respectively provides continuous working voltage for a single-phase detected electric energy meter and a first standard electric energy meter through the first high-power voltage regulating source, the central control board is in bidirectional communication with the first RLC load box, the first RLC load box outputs real current signals to the first standard electric energy meter and the single-phase detected electric energy meter respectively, signal output ends of the first standard electric energy meter and the single-phase detected electric energy meter are connected with an input end of the first error calculator, and an output end of the first error calculator is connected with an input end of the first error display.
The three-phase error testing device comprises a program-controlled three-phase power source, a second RLC load box, a second high-power voltage regulating source, a three-phase voltage transformer PT, a three-phase current transformer CT, a monitoring instrument, a three-phase on-site calibrator, a second error calculator and a plurality of second error displays, wherein a second communication port of a central control board is connected with a communication control port of the program-controlled three-phase power source, the program-controlled three-phase power source provides continuous working voltage for a three-phase checked electric energy meter through the second high-power voltage regulating source, the central control board is in bidirectional communication with the second RLC load box, the second RLC load box outputs real current signals to the three-phase current transformer CT and the three-phase checked electric energy meter respectively, and a signal output end of the three-phase current transformer CT is connected with current input ends of the monitoring instrument and the three-phase on-site calibrator respectively; the output end of the second high-power voltage regulating source is connected with the input end of the three-phase voltage transformer PT, the signal output end of the three-phase voltage transformer PT is respectively connected with the voltage input ends of the monitoring instrument and the three-phase on-site calibrator, the signal output ends of the three-phase on-site calibrator and the three-phase detected electric energy meter are connected with the input end of the second error calculator, and the output end of the second error calculator is connected with the input end of the second error display.
The first error calculator is in bidirectional communication with the central control board.
And the second error calculator is in bidirectional communication with the central control board, and a second standard electric energy meter is arranged in the three-phase on-site calibrator.
According to the technical scheme, the invention has the advantages that: firstly, the invention can adopt the real load of the simulated field electricity consumption, and test the metering error of the ammeter under the actual electricity consumption condition; secondly, the invention can output the actual load curve of the operation of the ammeter, thereby helping to know and master the operation metering condition of the ammeter more closely and accurately; third, the invention tests the power carrier communication capability of the detected electric energy meter through the external carrier meter controller under the condition of real load, and can more truly reflect the environment of the user site.
Drawings
FIG. 1 is a system block diagram of the present invention;
fig. 2 is a general operational flow diagram of the present invention.
Detailed Description
As shown in fig. 1, a real load test system of an electric energy meter comprises an upper computer, wherein the upper computer is in bidirectional communication with a central control board, the central control board is respectively in bidirectional communication with a single-phase error test device 1 for carrying out error test on a single-phase detected electric energy meter and a three-phase error test device 2 for carrying out error test on a three-phase detected electric energy meter, and the central control board is respectively used for supplying power to the single-phase error test device 1 and the three-phase error test device 2. The central control board adopts a main control chip, and the main control chip is an STC89C516 main control chip.
As shown in fig. 1, the single-phase error testing device 1 includes a program-controlled single-phase power source, a first RLC load box, a first high-power voltage regulating source, a first standard electric energy meter, a first error calculator and a plurality of first error displays, a first communication port of the central control board is connected with a communication control end of the program-controlled single-phase power source, the program-controlled single-phase power source respectively provides continuous working voltages for the single-phase detected electric energy meter and the first standard electric energy meter through the first high-power voltage regulating source, the central control board is in bidirectional communication with the first RLC load box, the first RLC load box outputs real current signals to the first standard electric energy meter and the single-phase detected electric energy meter respectively, signal output ends of the first standard electric energy meter and the single-phase detected electric energy meter are connected with an input end of the first error calculator, and an output end of the first error calculator is connected with an input end of the first error display. The first error calculator is in bidirectional communication with the central control board.
As shown in fig. 1, the three-phase error testing device 2 includes a program-controlled three-phase power source, a second RLC load box, a second high-power voltage regulating source, a three-phase voltage transformer PT, a three-phase current transformer CT, a monitoring instrument, a three-phase on-site calibrator, a second error calculator and a plurality of second error displays, wherein a second communication port of the central control board is connected with a communication control port of the program-controlled three-phase power source, the program-controlled three-phase power source provides continuous working voltage for a three-phase inspected electric energy meter through the second high-power voltage regulating source, the central control board is in bidirectional communication with the second RLC load box, the second RLC load box outputs real current signals to the three-phase current transformer CT and the three-phase inspected electric energy meter respectively, and signal output ends of the three-phase current transformer CT are respectively connected with current input ends of the monitoring instrument and the three-phase on-site calibrator; the output end of the second high-power voltage regulating source is connected with the input end of the three-phase voltage transformer PT, the signal output end of the three-phase voltage transformer PT is respectively connected with the voltage input ends of the monitoring instrument and the three-phase on-site calibrator, the signal output ends of the three-phase on-site calibrator and the three-phase detected electric energy meter are connected with the input end of the second error calculator, and the output end of the second error calculator is connected with the input end of the second error display. And the second error calculator is in bidirectional communication with the central control board, and a second standard electric energy meter is arranged in the three-phase on-site calibrator.
As shown in fig. 2, the third option is to select a single phase or a three phase, and the basic function test and the multi-function test are specifically as follows:
the direct current harmonic test refers to a direct current even harmonic test: the rated frequency is the harmonic wave of even times of fundamental wave frequency, which is called as 'even harmonic wave', such as 2, 4, 6 and 8 harmonic waves, the AC current of the electric energy meter is connected in series with diodes in the table body, the tested electric energy meter must be installed in pairs, and the reference current is selected to be 14.1A when in test, and the power factor is 1.
The voltage drop test is to realize the voltage quick drop test by operating the high-power voltage regulating source to quickly rise and fall in the normal voltage test process.
The power consumption test is to test the power consumption of the voltage loop and the current loop through an internal power consumption test module, and read the power data of the standard meter under the conditions of carrier communication and non-communication respectively to obtain the power consumption of the electric energy meter.
The carrier test is to read the carrier of the electric energy meter through an external power carrier reading controller in the process of the power-on test of the table body, and test the accurate success rate of reading information under different voltages and loads.
The mains isolation test means that a high-power isolation power supply is arranged in the test device, the test process is to ensure the test safety, and the isolation power supply is started to realize mains isolation.
The real load test is to start the RLC load box to carry out power load on the electric energy meter, and the test pair is the real load test.
The invention is further described below with reference to fig. 1 and 2.
The electric energy meter to be detected is installed and fixed on a wiring frame of the electric energy meter table, the table body is started, the electric energy meter to be detected is electrified to operate, the RLC load box is started, and the metering operation of the electric energy meter to be detected is driven by the actual load power consumption of the rear end. The upper computer expands a plurality of serial ports through the serial port server, and sets the load characteristic of the RLC load box through an RS485 or RS232 communication mode, so that the current magnitude and the phase angle characteristic of the load are adjusted. By adjusting the voltage of the power supply, the metering conditions of the electric energy meter under the conditions of rapid voltage drop and rapid voltage rise in the actual operation process can be simulated, and whether the electric quantity metering is inaccurate or not is judged.
The upper computer detects the metering value of the electric energy meter through serial port communication, the relative error of the electric energy meter is obtained through comparing the electric energy value measured by the detected electric energy meter with the electric energy value measured by the standard electric energy meter, and the relative error is compared with the upper error limit set by a user to judge whether the error of the electric energy meter is qualified or not. After the parameters of the meter (such as current specification, resistance-capacitance characteristics, sensitivity and the like) are determined, the upper computer sequentially adjusts the current of the load according to the set meter calibration parameters, performs error verification, and stores verification results in a database. Through the operation to load and on-off, the host computer still has the function of the load curve of test electric energy meter.
The program-controlled single-phase power source provides continuous working voltage for the single-phase detected electric energy meter through the first high-power voltage regulating source, the first RLC load box provides real current output for the single-phase detected electric energy meter and the first standard electric energy meter, each single-phase detected electric energy meter is calculated through the first error calculator and then is compared with the first standard electric energy meter to obtain data, and finally the data are displayed through the first error display.
The program-controlled three-phase power source provides a three-phase continuous working power supply for the three-phase inspected electric energy meter through the second high-power voltage regulating source, and meanwhile, the program-controlled three-phase power source calculates through the voltage transformer PT and displays an actual voltage value in real time through the monitoring instrument. The upper computer controls the second RLC load box to provide real load current for the three-phase detected electric energy meter, the real load current is converted by the current transformer CT, and after the three-phase on-site calibrator is calibrated, the real error value is finally displayed on the second error display through calculation and comparison of the second error calculator.
The first RLC load box and the second RLC load box adopted by the device are load boxes integrating resistance, inductance and capacitance, the electricity consumption of the electric energy meter on the user site is simulated truly, the electric energy metering is metered truly according to the actual electric quantity loss on the site, the power supply voltage passes through a high-power voltage source, the emergency of quick power failure and power up on the site is simulated truly, and the electric energy metering condition of the electric quantity under the site emergency is detected. The voltage transformer PT and the current transformer CT are used as accessories of the program-controlled three-phase power source and are fixed together with the program-controlled three-phase power source; the error calculator is an integrated part of the error display, is arranged in the error display, and the detected electric energy meter is an external detected object and is fixed at the corresponding position of the device only during the test;
the procedure at the time of testing was as follows:
1. selecting a starting button, powering on the platform body to run, installing the electric energy meter to be tested on a single-phase wiring frame or a three-phase wiring frame on the platform body to correspond to the epitope according to the model of the product to be tested, operating a crimping handle, fixing the electric energy meter to be tested, and adjusting the position of the photoelectric collector to enable the photoelectric collector to be aligned to the pulse output indicator lamp of the product to be tested; the photoelectric signal output by the pulse is collected under the action of the photoelectric collector and then transmitted to an error counter for error calculation;
2. operating a power control switch of the RLC load box, opening an operation display screen and configuring parameters; opening an upper computer, and setting parameter configuration according to stations and test items where the detected electric energy meter is located;
3. the system automatically performs precision error measurement and direct current even harmonic test on the detected electric energy meter on the self-meter frame according to the setting content;
4. the power output of the console body is controlled to finish the performance test communication test of the console body;
5. after the test is finished, a test finishing button is pressed to turn off the power switch.
The invention can simulate the real load of the site electricity consumption, and test the metering error of the ammeter under the actual electricity consumption condition; the invention can output the actual load curve of the operation of the ammeter, and help to know and master the operation metering condition of the ammeter more closely and accurately; under the condition of real load, the invention tests the power carrier communication capability of the detected electric energy meter through the external carrier meter controller, and can more truly reflect the environment of the user site.
Claims (3)
1. The utility model provides a real load test system of electric energy meter which characterized in that: the system comprises an upper computer, wherein the upper computer is in bidirectional communication with a central control board, the central control board is respectively in bidirectional communication with a single-phase error testing device (1) for carrying out error testing on a single-phase electric energy meter to be tested and a three-phase error testing device (2) for carrying out error testing on a three-phase electric energy meter to be tested, and the central control board is respectively used for supplying power to the single-phase error testing device (1) and the three-phase error testing device (2);
the central control board adopts a main control chip which is an STC89C516 main control chip;
the single-phase error testing device (1) comprises a program-controlled single-phase power source, a first RLC load box, a first high-power voltage regulating source, a first standard electric energy meter, a first error calculator and a plurality of first error displays, wherein a first communication port of a central control board is connected with a communication control end of the program-controlled single-phase power source, the program-controlled single-phase power source respectively provides continuous working voltage for the single-phase detected electric energy meter and the first standard electric energy meter through the first high-power voltage regulating source, the central control board is in bidirectional communication with the first RLC load box, the first RLC load box outputs real current signals to the first standard electric energy meter and the single-phase detected electric energy meter respectively, signal output ends of the first standard electric energy meter and the single-phase detected electric energy meter are connected with an input end of the first error calculator, and an output end of the first error calculator is connected with an input end of the first error display;
the three-phase error testing device (2) comprises a program-controlled three-phase power source, a second RLC load box, a second high-power voltage regulating source, a three-phase voltage transformer PT, a three-phase current transformer CT, a monitoring instrument, a three-phase on-site calibrator, a second error calculator and a plurality of second error displays, wherein a second communication port of a central control board is connected with a communication control port of the program-controlled three-phase power source, the program-controlled three-phase power source provides continuous working voltage for a three-phase inspected electric energy meter through the second high-power voltage regulating source, the central control board is in bidirectional communication with the second RLC load box, the second RLC load box outputs real current signals to the three-phase current transformer CT and the three-phase inspected electric energy meter respectively, and a signal output end of the three-phase current transformer CT is connected with current input ends of the monitoring instrument and the three-phase on-site calibrator respectively; the output end of the second high-power voltage regulating source is connected with the input end of the three-phase voltage transformer PT, the signal output end of the three-phase voltage transformer PT is respectively connected with the voltage input ends of the monitoring instrument and the three-phase on-site calibrator, the signal output ends of the three-phase on-site calibrator and the three-phase detected electric energy meter are connected with the input end of the second error calculator, and the output end of the second error calculator is connected with the input end of the second error display.
2. The real load test system of an electric energy meter of claim 1, wherein: the first error calculator is in bidirectional communication with the central control board.
3. The real load test system of an electric energy meter of claim 1, wherein: and the second error calculator is in bidirectional communication with the central control board, and a second standard electric energy meter is arranged in the three-phase on-site calibrator.
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Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108919171B (en) * | 2018-06-29 | 2023-12-26 | 国网宁夏电力有限公司固原供电公司 | Ammeter internal fault check meter |
| CN110888100A (en) * | 2019-11-29 | 2020-03-17 | 国网重庆市电力公司电力科学研究院 | Single-phase intelligent electric energy meter online on-load detection system and method |
| CN112731262A (en) * | 2020-12-11 | 2021-04-30 | 国网上海市电力公司 | Verification equipment for electric energy meter |
| CN114114130B (en) * | 2021-09-18 | 2024-05-14 | 宁夏隆基宁光仪表股份有限公司 | Electric energy meter testing method, system and device based on simulation site actual load |
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