Question

Question 4 (20 marks total) (I) (10 marks) The first part of the question relates to the power system illustrated in Figure 4. This system incorporates a zoned protection system, with circuit breakers labelled from B1 to B32. Discuss how this protection system operates. As part of your answer you should address the following points: (a) Draw in your answer booklet the zones of protection for this system. (b) You should outline which breakers would operate for faults at different locations. For example which breakers operate for a fault at bus 3, or in the middle of transmission line 2 - 3? (C) Discuss the different protection relays that would be used for different fault types. For example what relay types would be needed for the breaker B32, to address faults on Bus 3, or faults on the transmission line 2 - 3, and how are they configured? Bus 1 T2 Line 1 - 2 Bus 2 Do 2 Ti AC 13E B12 B21 | B2 YA A Bus 3 AYB T3 Line 1-3 Line 2-3 CHE B13 B31 B32 B23 B3 모 3 X Figure 4 : Power System for Question 5

Answer 1

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