(Q.2 ) Line impedances of the following power system are, Z12 (4+j60) 2. R12 and R32 are directional impedance relays that control the breakers B12 and B32 respectively. Zone 1 of R12 is set to protect 70% of line 1-2, Zone 2 of R12 is set to protect 110% of line 1-2 and Zone 3 of R12 is set to protect 100% of line 1-2 plus 110% of line 2-4. Find the Z23 = (5+j50) and Z24 %3D possible largest ratio of (I32/I12) for R12 relay to see the fault at bus 4. 21 R32 31 1 R12 B12 B32 4.

(Q.2 ) Line impedances of the following power system are, Z12 (4+j60) 2. R12 and R32 are directional impedance relays that control the breakers B12 and B32 respectively. Zone 1 of R12 is set to protect 70% of line 1-2, Zone 2 of R12 is set to protect 110% of line 1-2 and Zone 3 of R12 is set to protect 100% of line 1-2 plus 110% of line 2-4. Find the Z23 = (5+j50) and Z24 %3D possible largest ratio of (I32/I12) for R12 relay to see the fault at bus 4. 21 R32 31 1 R12 B12 B32 4.

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter6: Power Flows

Section: Chapter Questions

Problem 6.46P

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