Table 111: OOSPPAM Non group settings (advanced)
Name Values (Range) Unit Step Default Description
StartAngle 90.0 - 130.0 Deg 0.1 110.0 Angle between two rotors to get the start
signal, in deg
TripAngle 15.0 - 90.0 Deg 0.1 60.0 Maximum rotor angle to allow trip signals,
in deg
7.6.6 Monitored data
Table 112: OOSPPAM Monitored data
Name Type Values (Range) Unit Description
CURRENT REAL - A Magnitude of the
measured positive-
sequence current, in A
VOLTAGE
REAL - kV Magnitude of the
measured positive-
sequence voltage, in V
R
REAL - % Real part of measured
positive-sequence
impedance % of UBase/
(sqrt(3)*IBase)
X
REAL - % Imaginary part of
measured positive-seq
impedance % of UBase/
(sqrt(3)*IBase)
SLIPFREQ
REAL - Hz Slip frequency in Hz
ROTORANG REAL - deg Rotor angle as estimated
by the out-of-step
function
UCOSPHI
REAL - kV Estimated Ucos(Phi)
voltage during pole slip,
in V
7.6.7 Operation principle
General
Under balanced and stable conditions, a generator operates with a constant rotor angle
(power angle), delivering active electrical power to the power system, which is
approximately equal to the input mechanical power on the generator axis.The currents
and voltages are constant and stable. An out-of-step condition is characterized by
periodic changes in the rotor angle, that leads to a wild flow of the synchronizing
power; so there are also periodic changes of rotational speed, currents and voltages.
When displayed in the complex impedance plane, these changes are characterized by
a cyclic change in the complex load impedance Z(R, X) as measured at the terminals
of the generator, or at the location of the instrument transformers of a power line
connecting two power subsystems. This is shown in
Figure 111.
Section 7 1MRK502052-UEN B
Impedance protection
262
Technical manual