1
GATE EE 2008
+1
-0.3
A two machine power system in shown below. Transmission line $$XY$$ has positive sequence impedance of $${Z_1}\Omega$$ and zero sequence impedance of $${Z_0}\Omega$$
An $$'a'$$ phase to ground fault with zero fault impedance occurs at the centre of the transmission line. Bus voltage at $$X$$ and line current from $$X$$ to $$F$$ for the phase $$'a',$$ are given by $${V_a}$$ Volts and $${{\rm I}_a}$$ Amperes, respectively. Then, the impedance measured by the ground distance relay located at the terminal $$X$$ of line $$XY$$ will be given by
A
$${Z_1}/2\Omega$$
B
$${Z_0}/2\Omega$$
C
$$\left( {{Z_0} + {Z_1}} \right)/2\Omega$$
D
$${V_a}/{{\rm I}_a}\,\Omega$$
2
GATE EE 2006
+1
-0.3
In a biased differential relay the bias is defined as a ratio of
A
Number of turns of restraining and operating coil
B
Operating coil current and restraining coil current
C
Fault current and operating coil current
D
Fault current and restraining coil current
3
GATE EE 2004
+1
-0.3
The transmission line distance protection relay having the property of being inherently directional is
A
impedance relay
B
MHO relay
C
OHM relay
D
reactance relay
4
GATE EE 2002
+1
-0.3
Consider the problem of relay co-ordination for the distance relays $$R1$$ and $$R2$$ on adjacent lines of a transmission system figure. The Zone $$1$$
and Zone $$2$$ settings for both the relays are indicated on the diagram. Which of the following indicates the correct time setting for the Zone $$2$$ of relays $$R1$$ and $$R2.$$
A
$$TZ{2_{R1}} = 0.6s,\,\,TZ{2_{R2}} = 0.3s$$
B
$$TZ{2_{R1}} = 0.3s,\,\,TZ{2_{R2}} = 0.6s$$
C
$$TZ{2_{R1}} = 0.3s,\,\,TZ{2_{R2}} = 0.3s$$
D
$$TZ{2_{R1}} = 0.1s,\,\,TZ{2_{R2}} = 0.3s$$
EXAM MAP
Medical
NEET