ABB REG670 - Page 290

P
70º
80º
90º
Underexcitation Protection
Operation area
IEC06000450-2-en.vsd
Q
IEC06000450 V2 EN
Figure 147: Suitable area, in the PQ-plane, for protection operation
Often the capability curve of a generator describes also low excitation capability of the
generator, see figure 148.
Section 8 1MRK 502 071-UEN -
Impedance protection
284 Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Application manual