ABB REG670 - Page 298

1
rot
ref
j C
Z
w =
EQUATION2511 V1 EN
Where:
2
inj
f w p = ×
EQUATION2512 V1 EN
The injected frequency f
inj
of the square wave, is a set value, different from the
fundamental frequency (50 or 60 Hz). The injected frequency can be set within the
range 75 – 250 Hz with the recommended value 113 Hz in 50 Hz systems and 137 Hz
in 60 Hz systems.
R
series
is a resistance in the REX061 unit used to protect against overvoltage to the
injection unit. Such overvoltages can occur if the unit is fed from static excitation
system.
The injection unit REX060 is connected to the generator and to IED as shown in figure
155.
Section 8 1MRK 502 071-UEN -
Impedance protection
292 Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Application manual