protection (reference angle set to 0) to trip if the active power from the generator is lessthan about 2%. One should set the overpower protection (reference angle set to 180) to tripif the power flow from the network to the generator is higher than 1%.Underpower protection Overpower protectionQ QP POperating pointwithoutturbine torqueMargin MarginOperateLine OperateLineOperating pointwithoutturbine torqueIEC09000019-2-en.vsdIEC09000019 V2 ENFigure 92: Reverse power protection with underpower or overpower protection7.8.3 Setting guidelinesGlobalBaseSel: Selects the global base value group used by the function to define (IBase),(VBase) and (SBase).Operation: With the parameter Operation the function can be set Enabled/Disabled.Mode: The voltage and current used for the power measurement. The setting possibilitiesare shown in table 33.Table 33:Complex power calculationSet valueMode Formula used for complex power calculationA, B, C * * *A A B B C CS V I V I V I= × + × + ×EQUATION2055-ANSI V1 EN (Equation 45)Arone * *AB A BC CS V I V I= × - ×EQUATION2056-ANSI V1 EN (Equation 46)PosSeq *3 PosSeq PosSeqS V I= × ×EQUATION2057-ANSI V1 EN (Equation 47)Table continues on next page1MRK 505 337-UUS - Section 7Current protection211Application manual
