The Design And Implementation Of Multi-functional Harmonic Power Meter

As the primary energy in the national economy and people’s lives, themeasurement of electric energy involves economic profits of three parties, namely theelectricity generating party, electricity supplying party and electricity consumingparty. With the wide application of power electronics in various industrialdepartments, the harmonic effect in the power grid is on the rise, and as a result, theregular watt-hour meter can no longer measure accurately under the harmoniccondition. Research and application of power meter with harmonic analysis andmeasurement function can help improve the contradiction in charging for electricity,which can provide a necessary basis for making harmonic treatment plans.The Development stages and current research status of watt-hour meter has beensummarized firstly, the measuring principle of electronic watt-hour meter has beenillustrated, and the standard of multi-function electronic watt-hour meter has beenintroduced. And then the harmonic influence on the measurement of electricity hasbeen analyzed, several current harmonic measurement methods have been introduced,the widely-used FFT principle has been fully illustrated, and appropriate electricitymetering measures have been proposed under harmonic effect. On the basis oftheoretical analysis, the design of high-accuracy and wide-range multi-functionelectronic watt-hour meter has been accomplished, the design principle for hardwareand realization method of software has been illustrated specifically, and unit circuit ofthe hardware as well as the module flow chart of some software have been put forward.Next, combining the theory with reality, effective measures in resisting interferenceand improving reliability of the watt-hour meter has been stated from both thehardware and software aspects in this paper. Finally, the testing methods and results ofthe multi-function watt-hour meter have been introduced. This meter has reached thedemands from all expected goals in performance, function and accuracy.Multi-function electronic watt-hour meter in this paper has adopted a simple andpractical design plan, in which all the functions have been achieved, such as thesurvey control, electricity measurement, harmonic measurement and analysis. It hasreached the requirements from the measurement and control power meter on "remotesignal","remote control","remote measurement" and "remote regulation", withvarious advantages such as wide range, high accuracy, multi functions and easy networking. This meter has a good application value in the intelligent powerdistribution system and industrial automation system.