The Research Of Harmonic Measurement Method Based On FAFT Algorithm

With the increasing use of large number of electronic equipment the harmonic pollution of power system become more and more serious. The accident caused by power harmonic appears more. In order to ensure the power system's safety, it is necessary to establish the measuring and analysis system of harmonic to avoid and eliminate the power harmonic. At first, the paper discusses the theory of the current power harmonic detection methods. The characteristics and the applying area of the various methods are given. Then a multi-channel data-acquiring box is designed which choose SMC as core component as well as multi-channel 14-bit A/D converter. A virtual power harmonic detection system is designed on portable computer by using LabView as programminglanguage and the fast anti-alias--FAFT algorithm is applied to thesystem to realize the measurement of the parameters of high level harmonic ratio(HRUn HRIn)s total harmonic distortion(THD)s active powers reactive powers power factor etc.At last, a three-phase-four-line voltages current testing condition is set up, the system and the THS720P oscillograph are used to test the voltage current of different harmonic content. The result of the experiment show that the system have the advantage of simple structure credible performance and high precision.