DISTRIBUTION-SYSTEM HARMONIC WORST-CASE DESIGN USING A GENETIC ALGORITHM

IEEE Standard 519 suggests that utility distribution buses should prov ide a voltage harmonic distortion level of less than 5% provided custo mers on the distribution feeder limit their load harmonic current inje ctions to a prescribed level. It is therefore desirable to anticipate voltage harmonics on distribution lines that have constantly changing characteristics due to line switching, capacitor switching, and load i mpedance changes, and are also subject to multiple harmonic sources wi th changing magnitudes and spectra. This paper outlines a technique fo r finding worst-case combinations of these distribution system variabl es in order to design solutions to potential harmonic excesses. The nu mber of harmonic source-load combinations makes it desirable to use a Genetic Algorithm for this purpose.