8.7 Sensitive rotor earth fault protection, injection based
ROTIPHIZ (64R)
GUID-60B5DBE4-5942-471A-95DD-D6077894A8C1 v1
8.7.1 Identification
GUID-BA521452-3BE2-4D63-9FC1-58647166FFD9 v1
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Sensitive rotor earth fault protection,
injection based
ROTIPHIZ Rre< 64R
8.7.2 Application
GUID-1B61E4DF-46B9-4894-B065-D78198CC6C59 v1
GUID-4BF7B3BA-9CC3-4B5D-852E-63502FE475EB v2
The sensitive rotor earth fault protection, injection based (ROTIPHIZ, 64R), is used to
detect ground faults in the rotor windings of generators and motors. An independent
signal with a frequency different from the generator rated frequency is injected into the
rotor circuit.
To implement the above concept, a separate injection device is required. The injection
device generates a square wave voltage signal which is fed into the rotor winding of
the generator.
The magnitude of the injected voltage signal is measured at the injection point; the
magnitude of the injected current is measured through a resistive shunt located within
REX060. These two measurements are fed to the IED. Based on these two measured
quantities, the IED determines the rotor winding resistance to ground. The resistance
value is then compared to the preset fault resistance alarm and trip levels.
The protection function can detect ground faults in the entire rotor winding and
associated connections. The function can also detect excitation system ground faults on
the AC side of the excitation rectifier. The measuring principle used is not influenced
by the generator operating mode and is fully functional even with the generator at
standstill.
8.7.2.1 Rotor earth fault protection function
GUID-4869A8DB-F725-4EF1-8FD0-42A9AECDD69D v2
The injection to the rotor is schematically shown in figure
154.
Section 8 1MRK 502 071-UUS A
Impedance protection
312 Generator protection REG670 2.2 ANSI and Injection equipment REX060, REX061, REX062
Application manual
To Next Page
Loading...
