A real-time comparison method for measuring operat

2022-08-03
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A real-time comparison method for measuring and operating errors of broadband watt hour meters

Jinchengli's invention, which is regarded as the company's mission, has no limit on creativity and continues to create maximum value for customers. Today, I'd like to introduce a national invention patent - a real-time comparison method for measuring operation errors of broadband watt hour meters. The patent was applied by State Grid Corporation of China, Jiangsu electric power company, Electric Power Research Institute of Jiangsu electric power company and Fujian Yirong Information Technology Co., Ltd. and was authorized to announce on August 8, 2017

content description

the invention relates to a real-time comparison method for measuring operation errors of broadband electric energy meters, belonging to the technical field of electric energy measurement

invention background

at present, the electric energy metering devices put into actual operation by the State Power Corporation are basically the technical schemes of traditional electromagnetic current transformer, traditional electromagnetic voltage transformer and supporting traditional electric energy meter. The scheme has mature technology, stable performance and simple maintenance, so it has been widely used. However, as the power system becomes larger and larger, the transmission characteristics become more complex. In particular, many current electric energy measurement schemes only consider the energy transmission within the power frequency range and do not take the harmonic factor into account, which seriously affects the accuracy and fairness of measurement. Therefore, it is particularly necessary to invent a method that can widely evaluate the measurement characteristics of existing electric energy meters

at present, the measurement accuracy of traditional electric energy meters at home and abroad is basically tested by comparing the electric energy pulse measurement of the standard metering device with that of the electric energy meter before installation; For the detection of electric energy meters that have been put into field operation, the influence of the electromagnetic characteristics of the traditional electromagnetic transformer is generally not considered, that is, there is a lack of real-time analysis and comparison of the power quality of the metering secondary incoming line. Therefore, the verification results are often not ideal, resulting in the reduction of the accuracy and reliability of the electric energy meter in the substation

content of the invention

the purpose of the invention is to overcome the lack of real-time analysis and comparison of the power quality of the secondary incoming line of the metering when detecting the metering accuracy of the traditional power metering device, and the poor verification results, resulting in the reduction of the accuracy and reliability of the power metering of the substation. The real-time comparison method for measuring operation errors of broadband watt hour meters of the invention is applicable to the calibration of watt hour meters before leaving the factory, various scientific research institutions carry out experiments related to the measurement accuracy of watt hour meters in the laboratory, and carry out on-site experiments and tests on installed and put into use Watt hour meters such as substations, so as to ensure the accuracy and reliability of watt hour measurement, and has a good application prospect

the figure shows the flow chart of the optimization selection method for improving the metering accuracy of the operating state of the voltage transformer of the invention

and various adhesive resins and sealing modified resins. In order to achieve the above purpose, the technical scheme adopted by the invention is: a real-time comparison method for the metering operation error of the broadband watt hour meter, which is characterized by the following steps: step (1), the current at the secondary side The voltage signals are respectively output to synchronously sample the broadband watt hour meter to be tested and the standard watt hour meter, and output the first current and voltage sampling signals corresponding to the broadband watt hour meter composed of the full-automatic tensile testing machine system to be tested, and the second current and voltage sampling signals corresponding to the standard watt hour meter; Step (2), outputting the electric energy pulses of the two broadband electric energy meters to be measured to the first electric energy pulse metering unit and the second electric energy pulse metering unit respectively, and outputting the first electric energy metering signal and the second electric energy metering signal; Step (3), input the first current and voltage sampling signals and the second current and voltage sampling signals respectively into the electric energy metering unit, perform real-time electric energy calculation through the electric energy metering unit for the broadband electric energy meter to be measured and the standard electric energy meter, and output the third electric energy metering signal corresponding to the broadband electric energy meter to be measured and the fourth electric energy metering signal corresponding to the standard electric energy meter; Step (4), input the first electric energy measurement signal, the second electric energy measurement signal, the third electric energy measurement signal and the fourth electric energy measurement signal into the electric energy comparison unit respectively, and the electric energy comparison unit conducts periodic continuous calculation and comparison of the four electric energy measurement signals, with an interval of 1 minute; Step (5), input the first current and voltage sampling signals and the second current and voltage sampling signals to the harmonic analysis unit respectively, and conduct real-time harmonic analysis on the two current and voltage sampling signals through the harmonic analysis unit

the above-mentioned real-time comparison method for measuring operation errors of broadband watt hour meters is characterized in that: step (1) the broadband watt hour meter to be tested and the standard watt hour meter use high-speed and high-precision analog-to-digital conversion chip to synchronously sample the current and voltage signals at the secondary side. The model of the analog-to-digital conversion chip is ad7606, the sampling speed is 12.8, the rotation of the force measuring pointer will slow down kHz, and the number of sampling bits is 16

step (2) the first electric energy pulse metering unit and the second electric energy pulse metering unit output the first electric energy metering signal and the second electric energy metering signal by collecting electric energy pulses and counting the electric energy pulses in unit time to obtain the corresponding electric energy metering signal

step (3), carry out real-time electric energy calculation, including active power calculation and reactive power calculation, through the broadband electric energy meter and standard electric energy meter to be measured by the electric energy measurement unit

step (4), the method of periodic continuous calculation and comparison of four electric energy measurement signals by the electric energy comparison unit is as follows: 1) the electric energy calculation unit calculates the electric energy of each electric energy measurement signal in real time, accumulates the electric energy values of each circuit through the integrator, and performs periodic continuous calculation and comparison under the control of the timer; 2) Taking the second electric energy measurement signal as the standard, the first electric energy measurement signal, the third electric energy measurement signal and the fourth electric energy measurement signal are periodically compared for active electric energy through the electric energy calculation unit; 3) Taking the second electric energy measurement signal as the standard, the first electric energy measurement signal, the third electric energy measurement signal and the fourth electric energy measurement signal are compared periodically for reactive electric energy

step (5) the method of real-time harmonic analysis of two current and voltage sampling signals through the harmonic analysis unit, including 1) fast Fourier transform of two current and voltage sampling signals; 2) Calculate the amplitude and phase of power frequency component and harmonic component in frequency domain

the aforementioned real-time comparison method for measuring operation errors of broadband watt hour meters is characterized in that the amplitude and phase of the harmonic component are 21st harmonic signals

the beneficial effect of the invention is that the real-time comparison method for the measurement and operation error of the broadband watt hour meter of the invention is applicable to the calibration of the watt hour meter before leaving the factory, the relevant experiments on the measurement accuracy of the watt hour meter carried out by various scientific research institutions in the laboratory, the field experiments and detection of the installed and put into use watt hour meters such as substations, etc., so as to ensure the accuracy and reliability of the watt hour measurement, and has a good application prospect

for further information, please download the complete specification of the patent

relevant data download: [invention authorization] a real-time comparison method for measuring operation error of broadband watt hour meter pdf

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