Improve Of Square Demodulation Method On Flicker Measure And The Check To Digital Flicker Meter

The voltage fluctuation and the flicker are taken as an important index to judge thepower quality in IEC6100-3-7 of the EMC standard and GB12326-2000.This paperaims at the way recommended by IEC on flicker measure, mainly analyzes the detection errorwhich rests with the frequency's move component of the single frequency square-wave signalfirstly, reveals that the way of square detection which may ignore the frequency's move due tothe square calculate and more, the part within 35Hz will cause the flicker measuring error.Furthermore,it proposes a improved way which based on the IEC recommended way, itindicates that the improved way can enhance the accuracy of flicker measurement on thecondition of no increased calculation task by the deducted theory and confirmed simulation.Secondly, this paper discusses the check to the digital Flickermeter, produces the standarddigital flicker signal of single frequency, bi-frequencies and the multi-frequencies, obtains thecorresponding S (t ) value by inputting it into the digital Flickermeter, checks theflickermeter by comparing the different value of different way. It proves that this way cancheck every frequency's accuracy of digital flickermeter.