ABB REG670 Applications Manual page 289

1MRK 502 071-UEN -
Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Application manual
noticed that the power limitations shown below is highly dependent on the network
impedance.
IEC06000322 V1 EN
Figure 146: The complex apparent power from the generator, at different angles
δ
To prevent damages to the generator block, the generator should be tripped at low
excitation. A suitable area, in the PQ-plane, for protection operation is shown in
figure 147. In this example limit is set to a small negative reactive power independent
of active power.
Q
en06000322.vsd
Section 8
Impedance protection
70º
80º
P
90º
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