Propagation characteristics of sag and harmonics in medium voltage distribution systems

The propagation characteristics of power quality disturbances, such as sag and harmonics, are examined in this paper. The scope of the study is limited to large disturbances at the industrial and utility substation level, where disturbances propagate typically from one industrial customer to another through the utility networks. Based on studies on a typical distribution system, a few generalized conclusions were drawn. Even though these conclusions are case-specific, in the opinion of the authors, depending upon the closeness of the actual system to the reference system selected, these conclusions can be validated and extrapolated with relative ease using the judgement of the user.