Two 1-phase furnaces a and b are supplied at 80V by means of a Scott-connected transformer combination from a 3-phase, 6600V system. The voltage of furnace a is leading. Calculate the line current on the 3-phase side when the furnaces take 500kW at unity power factor and 800kW at 0.7 power factor lagging respectively. Drriw the corresponding vector diagrams.

Two 1-phase furnaces a and b are supplied at 80V by means of a Scott-connected transformer combination from a 3-phase, 6600V system. The voltage of furnace a is leading. Calculate the line current on the 3-phase side when the furnaces take 500kW at unity power factor and 800kW at 0.7 power factor lagging respectively. Drriw the corresponding vector diagrams.

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 3.25P: Consider a single-phase electric system shown in Figure 3.33. Transformers are rated as follows:...

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