1- A 3-phase 400KVA, 11000/416 transformer is delta-connected on the primary and star connected on the secondary. The primary resistance / phase is 4.3 2 and secondary resistance/phase is 0.0022. if the iron loss is 990 watts. Determine the full load copper losses. 2- A three-phase transformer has 3300/400 V, D/Y connected and working on 50Hz. The line current on the primary side is 12A and secondary has a balanced load at 0.8 lagging p.f. Determine the, i) Secondary phase voltage ii) Line current iii) Output power 4 * Remember For 中 3phase Tr 1-Connected system connected system. A- * 34 = 3 V I 2... COS = S34 зиф 9 = FL = √3 3 P3 = 3 * Zba = 3 Ye baze 3+ * Any given Power is 3phase * Any Jiven voltage I S Lone が is chosen base Upase S chosen Power: P oltage according to Rating of Tr. ording For A-D sr 人一人 3ph Tr the same as the problem. For A-1 3ph T to Vp/Vs Ratio a Vp/Vs a = Vē ·For A-D 3ph Tr √3

1- A 3-phase 400KVA, 11000/416 transformer is delta-connected on the primary and star connected on the secondary. The primary resistance / phase is 4.3 2 and secondary resistance/phase is 0.0022. if the iron loss is 990 watts. Determine the full load copper losses. 2- A three-phase transformer has 3300/400 V, D/Y connected and working on 50Hz. The line current on the primary side is 12A and secondary has a balanced load at 0.8 lagging p.f. Determine the, i) Secondary phase voltage ii) Line current iii) Output power 4 * Remember For 中 3phase Tr 1-Connected system connected system. A- * 34 = 3 V I 2... COS = S34 зиф 9 = FL = √3 3 P3 = 3 * Zba = 3 Ye baze 3+ * Any given Power is 3phase * Any Jiven voltage I S Lone が is chosen base Upase S chosen Power: P oltage according to Rating of Tr. ording For A-D sr 人一人 3ph Tr the same as the problem. For A-1 3ph T to Vp/Vs Ratio a Vp/Vs a = Vē ·For A-D 3ph Tr √3

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

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.10P: A single-phase step-down transformer is rated 13MVA,66kV/11.5kV. With the 11.5 kV winding...

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A 3-phase 10OOKVA, 11000O/416 transformer is delta-connected on the primary and star connected on the secondary. The primary resistance / phase is 1.45 Q and secondary resistance/phase is 0.0006 Q. determine the efficiency on full-load at 0.85 power factor lagging if the iron loss is 1770 W.* 1 Add file
6. The figure below shows a single-line-diagram of part of a power system. For each transformer in the diagram state a suitable connection method, giving reasons for your suggested connection method. G1 G1 800MW 200MW 15kV 10kV T1-T4 88 T5-T6 250MVA each 125MVA each 330/15kV 88/10kV Line 1 Line 2 T7-T8 100MVA each 330/88kV T9 T10-T11 50MVA 50MVA each 88/66kV 88/11kV T12 2MVA 11/0.4kV Singe-phase loads
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