| With the reform of electrical enterprise that power plant separates from power grid step by step, power plants and electricity customers pay close attention to energy metering devices. Power enterprises attach more and more importance to the assessment of economic benefit. The core is to ensure the accuracy and reliability of energy measurement in trade settlement process, as a result, the technical management of energy metering device becomes more and more important.On the other hand, energy metering technology management faces a new situation, and highlights several new technical problems, such as:network size is growing; trading power and energy measurement devices are increasing; which requires standardized technology management under the conditions of limited manpower; implementation of multi-rate sub-period tariff policy requires clock of the electric energy meter owns a higher accuracy; numerously promotion of power electronics related technology, the increasing of nonlinear loads as harmonic pollution, the impact of harmonics on power measurement and analysis of response measures needs further study; now widely used traditional manual field calibration mode efficiency is low, which can not carry out real-time monitoring and fault warning. It is difficult to effectively control measures fault and reduce errors power.For the above, this article has mainly carried on the following several aspect analytical study work:Using the GPS technology, Harmonic measure theory, Different frequency harmonic injection test method, low high school equivalent circuit method and other measurement related technologies, with power line carrier technology, GPRS/PSTN communication technology. GPS technology is completed based on the clock power meter calibration and measurement of the voltage transformer secondary voltage drop. Based on add window interpolation FFT harmonic electricity measurement, standard table comparison test electrical energy table error online monitor, long-distance calibration, the second load voltage transformer secondary stress test, the current injection transformer secondary high-frequency harmonics of different frequency admittance method test. As while based on the proposed the voltage/current transformer, the equivalent impedance survey's voltage/current transformer low school high verification method (TV/TA) on the spot the real-time calibration method. This paper has carried on the error analysis and the uncertainty evaluation to the above each measuring technique.This article researched power metering device on line monitoring and remote calibration techniques can be applied to the domestic electricity grid systematically. The main contributions are as follows:(1) Based on GPS technology and according to multi-rate, multi-function power meter calibration requirements for the clock, this paper developed energy metering clock fundamental frequency testing and calibration devices. The device can use wireless and non-contact method to test energy meter clock error in the field. With the GPS precision timing, using GPS synchronized measure the amplitude of the voltages on both ends of the secondary circuit in the TV. And using the ratio of the difference between the two voltages and secondary voltage calculate the ratio worse of TV. To gain GPS real-time time scale on both ends of the secondary circuit in the TV respectively when the voltage signal pass zero and gain the difference between them to calculate angle difference. According to TV voltage transformer secondary circuit voltage vector, calculate the voltage transformer secondary circuit voltage drop.(2) Under the Hunan Electric Power Corporation and Electric Power Test Research Institute's works of harmonic test, from the theoretical point analyzed the principle of harmonics from harmonic source users. Proposed interpolation FFT harmonic power measurement algorithm based on Blackman window, using FFT butterfly sequence iteration formula compute power supply system grid parameters. Proposed identification method about the presence of harmonic source in the consolidated loads, and the measurement model that can add up harmonic energy based on harmonic characteristics and load flow direction, respectively, according to the national standards and the power industry regulations. Developed a kind of Multi-function, small size, friendly interface of harmonic energy measurement and online monitoring devices with harmonic source load adaptive features.(3) According to the requirement of calibration about the electric energy meter^ the second side pressure drop of potential transformer, the potential transformer and current transformer, and etc in the technical administrative code of electric energy metering DL/T448-2000, analysis the weakness of the traditional field calibration way. Through analysis the experience summary of years field work and according to the practical application of the electric energy meter, "master meter comparation" is proposed to calibrate the error of the electric energy meter in field. Developing the field devices which the electric energy measurement realize remote monitoring and calibrating. Meanwhile the master station about management information system is developed by using network database technology.(4) According to the test code of transformer second side load and admittance, the method that achieve measuring the secondary circuit load and admittance of the potential transformer and current transformer online which using the remote monitoring and calibrating system in the electric energy metering device is introduced. Analysis the main factor that which influences the impedance and admittance of the secondary circuit, pointing out several statuses that causes the changes of the impedance and admittance of the transformer. Through observing numerical value and phase angle change in a period of time to judge the failure source. On this basis, the method of measure in different frequency about inject harmonic components is proposed in this paper, based on which the online test method of the impedance and admittance of the secondary load is deduced in the paper.(5) The document analyzed the traditional transformer model of error on-site checking and testing, It is pointed out the transformer on-site calibration of the defects and shortcomings; The document also analyzed the technical principles of "low-proofing to high" of the current transformer and voltage transformer, It is proposed a method of real-time and on-site calibration on transformer error in the measurement device in a remote calibration and monitoring system.(6) The document described hardware implementations of remote test and monitoring system of measurement equipment, including system structure, communication networks, lower computer display and monitoring and so on. It analyzed needs of the main master station software of the system and complete the system design of the database(7) Take national measurement specifications JJF1059-1999 "Evaluation and Expression of Uncertainty in Measurement" as the basis, It is analyzed and evaluated uncertainty of online monitoring of energy measurement devices and remote calibration system of measuring, The system can be used as the field testing standards onâ… ,â…¡,â…¢class of energy metering device from the field test data and theoretical analysis.This study has a high theoretical significance and it provides a practical, efficient and reliable tools and methods for him modernization of electric energy metering management technology. It is pointed out the change proposes about administrative procedures to make it more scientific, reasonable and applicable according to the technological progress of fields on measurement.
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