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QUESTION 2 [20 Marks] a) For questions 2(a)-2(b), demonstrate all your calculations in per-unit and then convert to real values. The ratings of a three-phase round-rotor synchronous generator are given as 415 MVA, 45 KV, 0.84 power factor lagging. The characteristic reactance of the generator is 2.4 2. At rated voltage, if the generator is supplying full load 415 MVA at a 0.84 lagging power factor, determine the rotor angle 8, the electromotive force owing to the rotor field (E) (i.e., excitation EMF) of the generator, and the reactive power consumed by the load connected to the generator. [4 Marks] b) When the synchronous generator in question 2(a) is supplying the full real power load at rated voltage, i) What would be the rotor angle 8, load power factor, and the reactive power consumed by the load if E in 2(a) is increased by 35% ? [3 Marks] ii) What would be the rotor angle 8, load power factor, and the reactive power consumed by the load if E in 2(a) is decreased by 35% ? [3 Marks] c) Draw the impacts of different excitation EMFs of the synchronous generator in questions 2(a). 2(b)-(i) and 2(b)-(ii) on a single phasor diagram. Clearly mark the corresponding rotor angles 8, excitation currents, power factor angles, load voltages, and excitation EMFs. [5 Marks] d) A 300 MW interconnector connects region A (generators 1, 2, 3) to region B (generator 4, 5). The demand in region A and B are 1600 MW and 750 MW, respectively. Figure 4 shows the generator bids for one dispatch interval (quoted prices are in S/MWh). What will be the dispatched power for each generator and marginal prices in the two regions? If the interconnector is unregulated, how much revenue will it generate in one 5-minute dispatch interval? What will the dispatch be in the case where the interconnector has 5% losses? [5 Marks] 100 MW @ 80S 100 MW 70S 300 MW @ 40$ 300 MW@ 75$ 500 MW @ 30S 200 MW @ 300S 300 MW @ 35$ 400 MW @ 10S 200 MW @ 120S 300 MW@40S 150 MW @-10$ 100 MW@ 30$ 100 MW@ 20$ Gen 1 Gen 2 Gen 3 Gen 4 Gen 5 Region A Figure 4: Generator bids for one dispatch interval Region B