Field test results of a modified flickermeter Block 5 processing algorithm

IEC TC77/SC77A/WG2 is poised to consider maintenance and revisions to IEC Standard 61000-4-15. Based on the results of multiple CIGRE Working Groups and literature publications, it appears that discrepancies between measured short-term flicker severity values and user complaints can be reduced by making modifications to the so-called Block 5 processing algorithm. For such modifications to be fairly considered in the revision of any standard, it is necessary to establish both theoretical and practical/application bases. Prior work has established theoretical bases for changes in Block 5; in this paper are reported the results obtained from modified algorithms used at multiple sites for extended periods of time. Particular attention has been paid to quantify the extent of the differences obtained from the practical perspective of flicker limit compliance.