b) Figure Q4 shows a three-line network. The load currents and the fault levels at various locations are indicated in the figure. The operation time of both the CBS 0.4 s. The IDMT relay characteristic in terms of PSM is shown in Table Q4. Assume the pickup current of relay is set to 1.5 A, the TMS for Relay 1 is 0.1 an the ratio of current transformer as below CT ratio for relay R₁ = A₁= 100/1; CT ratio for relay R₂ = A2-200/1 Determine, (1) the TMS value for Relay 2 if fault of 3000A detected at Bus C, and (ii) the actual operating time of Relay 2 if fault of 4800A found at Bus B. Bus A Over current Relay 2 PSM T (sec) Bus B 20 2.2 Transmission line: IL = 200A Max: IF = 4800 A = CB Figure Q4 Table Q4 18 16 2.6 2.8 (Relay operating time 0.7 S fuse = Over current Relay 1 14 3.0 TX TMS) Transmission Bus line: IL = 100A D Transmission line: I₁ = 100A 12 3.2 10 3.5 Bus C Max: IF - 3000 A =

B:A 20 MVA transformer which may be called upon to operate at 30% overload, feeds 11 KV busbars through a circuit breaker: other circuit breakers supply outgoing feeders. The transformer circuit breaker is equipped with 1000/5 A CTs and the feeder circuit breakers with 400/5 A CTs and all sets of CTs feed induction type over current relays. The relays on the feeder circuits breakers have a 125% plug setting, and 0.3 time setting. If 3 ph fault current of 5000 A flows from the transformer to one of the feeders, find the operating time of the feeder relay, the minimum plug setting of the transformer relay and its time setting assuming a discrimination time margin of 0.5 sec. Relays having the following characteristics for TMS-1 PSM T in sec. 2 3.6 5 10 15 20 10 6 3.9 2.8 2.2 2.1

What is the significance of fault analysis in power systems, and how is fault location determined?

Discuss the concept of fault analysis in power systems. What are the types of faults and their effects?