R
Offset
Z1 or Z2
XoffsetZ1
Z1diameter
Z (apparent impedance)
Z1 = Z - (Xof
Z1diameter/2)
en06000456-2.vsd
IEC06000456 V2 EN
Figure 121:
Zone measurement in LEXPDIS protection function
The impedance Z1 is constructed from the measured apparent impedance Z and the
impedance corresponding to the centre point of the impedance characteristic (Z1 or
Z2). If the amplitude of this impedance is less than the radius (diameter/2) of the
characteristic, this part of the protection will operate.
If the directional restrain is set Off the impedance zone operation will start the
appropriate timer and LEXPDIS will trip after the set delay (
tZ1
or
tZ2
).
If the directional restrain is set On the directional release function must also operate
to enable operation. A new impedance is constructed from the measured apparent
impedance Z and the
XoffsetDirLine
point on the y-axis. If the phase angle of this
impedance is less than the set
DirAngle
LEXPDIS function will be released, see
figure
1MRK502052-UEN B
Section 7
Impedance protection
277
Technical manual
Summary of Contents for Relion REG670
Page 1: ...Relion 670 series Generator protection REG670 2 0 IEC Technical manual ...
Page 2: ......
Page 44: ...38 ...
Page 58: ...52 ...
Page 80: ...74 ...
Page 106: ...100 ...
Page 482: ...476 ...
Page 548: ...542 ...
Page 570: ...564 ...
Page 600: ...594 ...
Page 608: ...602 ...
Page 630: ...624 ...
Page 862: ...856 ...
Page 1094: ...1088 ...
Page 1226: ...1220 ...
Page 1250: ...1244 ...
Page 1297: ...1291 ...