Research On Electric Energy Metering Technology For Typical Nonlinear Power User

With the wide application of power electronic technology,there are more andmore rectifier equipments, inverter technologies, power inverter, electronic pressurecontrol equipments, electric arcfurnaces etc to be used in industrial production. Manyelectric energy metering of large nonlinear users are still common electronicwatt-hourmeter, which cannot achieve base and harmonic measuring respectively, making theharmonic source users pay less electric charge while polluting the power grid, whichbring huge losses to power supply enterprises and power users. So it is necessary tostudy the electric energy metering technology of typical nonlinear power users.This thesis collects all kinds of harmonic sources users and impact load,asymmetric load current, voltage waveform characteristics and the existing measuringmethods, analyzes the disadvantages of the existing measuring and the reasonablemeasurement methods by laboratory simulation and field netting comparative, andanalyz the current watt-hour meter measuring characteristics, and also puts forwardthe electric energy metering work methods of typical nonlinear power user on thebasis of these projects mentioned above.First of all, by collecting nonlinear power user’s current, voltage test reports, thethesis analyzes the characteristics of all kinds of harmonic sources users and impactload, asymmetric load current, voltage waveform.and also analyzes the influence ofharmonics on electric energy metering through a simplified model of power systemunder the existing measuring methods, then puts forward that we must use harmonicpower metering mode under the nonlinear load. Through the analysis of harmonics onelectric energy measurement and test, electric iron, electric arc furnace load electricitymetrology laboratory simulation, it is concluded that under the condition of harmonicinfluence,the power measured by fully power meter is less than actual powerconsumption; And analyzing the influence of harmonics on electric energy meteringthrough traction substation site screening,we can concluded that the fundamentalpower of the harmonic source users absorbed from the grid is greater than its fullpower of electricity.Comprehensive the above study, the typical nonlinear power users should install base wave (harmonic) watt-hour meter for electric energymetering.Then, by analyzing the current watt-hour meter measuring characteristics, wecan draw the conclusion that big users of nonlinear load should take harmonicelimination measures to reduce the effects of harmonic power;If the user cannot takeharmonic elimination measures, they can consider to use hardware filter installed basewave (harmonic) watt-hour meter.Finally,the thesis puts forward the electric energy metering methods of Jiangxitypical nonlinear grid power users, the conditions of the fundamental wave(harmonic), the technical conditions of the fundamental wave (harmonic) watt-hourmeter selection, the methods of fundamental wave (harmonic) watt-hour metercalibration and field calibration.