ABSTRACT
A distribution feeder provides service to unbalanced three-phase, twophase,andsingle-phaseloadsoveruntransposedthree-phase,two-phase, andsingle-phaselinesegments. Thiscombinationleadstothethree-phase linecurrentsandthelinevoltagesbeingunbalanced. Inordertoanalyze theseconditionsaspreciselyaspossible,itwillbenecessarytomodelall three phases of the feeder as accurately as possible. However, many times onlya“ballpark”answerisneeded. Whenthisisthecase,someapproximate methodsofmodelingandanalysiscanbeemployed. Itisthepurposeof thischaptertodevelopsomeoftheapproximatemethodsandleaveforlater chapters the exact models and analysis.
