DIRECTIONALCHARACTERISTICS OF DISTANCERELAYMHOELEMENTS:PARTI - A NEWMETHODOF ANALYSIS

A generalstudyof theeffectof line loadingon the responseof mho elementsothreverse faultshas necessitated thedevelopment of an altern- ate methodof representingthe responseof various typesof mho elements.Thispaperreviewstheusual methodsand establishesthe basisfor an alternate method.Withthisnewmethod,theresponseof any type of mho elementis represented by impedancesthatare viewedwithrespectto a characteristic circlepassing throughthe originand the reachpointon the R-X plane. Thischaracteristic is thesameforeachele- mentandis invariantwithpowersystemparametersand thefaulttype.Sincethecalculation of an impedance onlyis required,thismethodlendsitselfto general computeranalysesof mho elementresponseas wellas to manipulation of expressionsobtainedfrom power systemnetworkanalysis.