TB XRN2 02.00 E
13
Note:
In order to avoid any adverse interference voltage ef-
fects, for instance from contactors or relays, which may
cause overfunctions,
XRN2-1
should be connected
separately to the busbar.
4.6.1
Measuring principle of vector surge
supervision
When a synchronous generator is loaded, a rotor dis-
placment angle is build between the terminal voltage
(mains voltage U1) and the synchronous internal volt-
age (Up). Therefore a voltage is difference
∆
U is built
between Up and U1 (Fig. 4.4).
~
∆
U = I
jX
@
I
I
U
2
U
Mains
Z
Fig. 4.4: Equivalent circuit at synchronous generator in parallel
with the mains
Fig. 4.5: Voltage vectors at mains parallel operation
The rotor displacement angle
ϑ
between stator and
rotor is depending of the mechanical moving torque
of the generator shaft. The mechanical shaft power is
balanced with the electrical feeded mains power, and
therefore the synchronous speed keeps constant
(Fig. 4.5).
~
∆
U' I
'
jX
@
I
'
U
2
U
'
Mains
Z
Fig. 4.6: Equivalent circuit at mains failure
In case of mains failure or auto reclosing the generator
suddenly feeds a very high consumer load. The rotor
displacement angle is decreased repeatedly and the
voltage vector U
1
changes its direction (U
1
') (Fig. 4.6
and 4.7).
Fig. 4.7: Voltage vectors at mains failure
Summary of Contents for XRN2
Page 1: ...XRN2 Mains decoupling relay ...
Page 40: ...40 TB XRN2 02 00 E ...
