Question

Could you please help with solving the following question. Note answers are attached below: please show how these answers were obtained:

Q4. A single phase 50-Hz, 100 kVA, 11000/400 V-rms transformer is connected with the grid supply (Vi) as shown in Figure 3 15Ω j100 Ω j0.12 Ω 0.016 Ω Wll j50k 2 Load V240P 300k Ideal Transformer Figure 3 The load is connected on the secondary terminal to operate at 75% of its rated kVA at 0.8 lagging power factor. The grid supply voltage Vi is adjusted until the transformer output voltage V2 is at its rated value of 400 Vms. At these load operating conditions 4.a. Sketch the approximate equivalent circuit for this transformer and determine the parameters of this circuit 4 marks] 4.b. Calculate the transformer supply voltage (V) [6 marks] Calculate the transformer percentage voltage regulation. 4.c. [4 marks] 4.d. Calculate the transformer efficiency [6 marks 4.a I2-681-36.870 15+12.12 27.1 j100+j90.75 j190.750 187.5-36.870 Vdrop 1312.054450 Load 40020 Vi11963.134.45P j50k 2 1100020 |300k 2 Ideal Transformer 4.b. Vi1196324.45 4.c Vreg=8.75% 4.d Efficiency= 97.2%

Answer 1

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