Monitored Data - ABB RES670 Technical Manual

Section 7
Impedance protection
7.2.6
7.2.7
158

Monitored data

Table 89: OOSPPAM (78) Monitored data
Name Type
CURRENT REAL
VOLTAGE REAL
R REAL
X REAL
SLIPFREQ REAL
ROTORANG REAL
VCOSPHI REAL
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
Values (Range) Unit
- A
- kV
- %
- %
- Hz
- deg
- kV
Figure
Phasor measurement unit RES670 2.2 ANSI
1MRK 511 408-UUS A
PID-3539-MONITOREDDATA v8
Description
Magnitude of the measured
positive-sequence current, in
A
Magnitude of the measured
positive-sequence voltage, in
V
Real part of measured
positive-sequence impedance
% of VBase/(sqrt(3)*IBase)
Imaginary part of measured
positive-seq impedance % of
VBase/(sqrt(3)*IBase)
Slip frequency in Hz
Rotor angle as estimated by
the out-of-step function
Estimated Ucos(Phi) voltage
during pole slip, in V
GUID-787EEB01-B760-4D4B-AB4E-1DCD6ABFFF5E v6
42.
Technical manual