Page 539 - Industrial Power Engineering and Applications Handbook

Captive (emergency) power generation 16/513

Generator (G)
214 : Impedance protection or distance back-up protection
324 : Anti-motoring protection or low forward power protection
404 : Loss of excitation or loss of field protection
464 : Negative sequence protection
49-43 : ‘RTD’ protection
59-43 : Over voRage/Hz protection
64-G & : Generator stator ground
51-G fault protection
64-GF : Field ground protection
78-G : Pole slipping protection or out of step protection
814 : Abnormal frequency operation
87-G : Differential protection
Generator Transformer (GT)
49-GT : ‘RTD protection
51N-GT: Ground fault protection
63-GT : Gas protection
64R-GT: Restricted ground fault protection
87-GT : Differential protection

Main bus

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I

Unit auxiliary transformer (UT)
49-UT : ‘RTD’ protection
51-UT : Over-current protection
SIN-UT : Ground fault protection
63-UT : Gas protection
87-UT : Differential protection
64R-UT : Restricted ground fault
protection

Protection of unit auxiliary transformers no. 1 and 2 (shown only one transformer)

Figure 16.14 A typical protection scheme in a large generating station