GATE Electrical Engineering (EE) 2023 Solved Paper

Question : 20 of 65

Marks: +1, -0

For the three-bus power system shown in the figure, the trip signals to the circuit breakers B₁ to B₉ are provided by overcurrent relays R₁ to R₉, respectively, some of which have directional properties also. The necessary condition for the system to be protected for short circuit fault at any part of the system between bus 1 and the R-L loads with isolation of minimum portion of the network using minimum number of directional relays is

R₃ and R₄ are directional overcurrent relays blocking faults towards bus 2
R₃ and R₄ are directional overcurrent relays blocking faults towards bus 2 and R₇ is directional overcurrent relay blocking faults towards bus 3
R₃ and R₄ are directional overcurrent relays blocking faults towards Line 1 and Line 2, respectively, R₇ is directional overcurrent relay blocking faults towards Line 3 and R₅ is directional overcurrent relay blocking faults towards bus 2
R₃ and R₄ are directional overcurrent relays blocking faults towards Line 1 and Line 2, respectively.

Validate

Go to Question:

Prev Question

Next Question