5-100 G60 Generator Management Relay GE Multilin5.5 GROUPED ELEMENTS 5 SETTINGS5The saturation detector is implemented as a state machine (see below). "NORMAL" is the initial state of the machine. Whenin "NORMAL" state, the saturation flag is not set (SAT = 0). The algorithm calculates the saturation condition, SC. If SC = 1while the state machine is "NORMAL", the saturation detector goes into the "EXTERNAL FAULT" state and sets the satura-tion flag (SAT = 1). The algorithm returns to the "NORMAL" state if the differential current is below the first slope, SL, formore than 200 ms. When in the "EXTERNAL FAULT" state, the algorithm goes into the "EXTERNAL FAULT & CT SATU-RATION" state if the differential flag is set (DIF = 1). When in the "EXTERNAL FAULT & CT SATURATION" state, the algo-rithm keeps the saturation flag set (SAT = 1). The state machine returns to the "EXTERNAL FAULT" state if the differentialflag is reset (DIF = 0) for 100 ms.Figure 5–53: SATURATION DETECTION STATE MACHINEPHASE COMPARISON PRINCIPLE:The test for direction can be summarized by the following equation:(EQ 5.7)where: IR = restraining current, DIR = flag indicating that the phase comparison principle is satisfiedBL = breakpoint 1 setting, ITS, INS = current at the terminal and neutral sources, respectivelyK = factory constant of 0.25Figure 5–54: STATOR DIFFERENTIAL FINAL OUTPUT LOGIC830736A1.CDRNORMALSAT := 0SC(saturation condition)EXTERNAL FAULTSAT := 1EXTERNAL FAULTAND CT SATURATIONSAT := 1DIF = 0for 100 ms(|ID| < SL x IR) or (|ID| < PICKUP)AND(NOT (SC)) for 200 msSC = (|ID| < SL x IR) and (IR > BL)where:IR = restraint currentID = differential currentDIF = stator differential pickup flagSL = slope 1 settingBL = break point 1 settingPICKUP = pickup settingIf I TS B L> or I TS K I R⋅> and I TS 0.1 pu>( )( ) and I NS B L> or I NS K I R⋅> and I NS 0.1 pu>( )( )then DIR abs I TS∠ I NS∠–( ) 90°>=else DIR 1=842707A1.CDRANDANDANDOROROROR STATOR DIFF OPSTATOR DIFF OP CSTATOR DIFF OP BSTATOR DIFF OP ASTATOR DIFF PKP ASTATOR DIFF PKP BSTATOR DIFF PKP CSTATOR DIFF SAT ASTATOR DIFF SAT BSTATOR DIFF SAT CSTATOR DIFF DIR ASTATOR DIFF DIR BSTATOR DIFF DIR CFLEXLOGIC OPERANDFLEXLOGIC OPERANDSFLEXLOGIC OPERANDSFLEXLOGIC OPERANDSFLEXLOGIC OPERANDFLEXLOGIC OPERANDFLEXLOGIC OPERAND
