Example 5. A 3-phase 4-wire 400/231 volt, 50 Hz system has a balanced 3-phase motor load of 20 kW at a power factor 0.8 lagging and 1-phase loads 25 A at unity p.f., 45 A at p.f. 0.9 leading and 25 A at p.f. 0.8 lagging, the phase sequence being in the order given. Determine the current in each line and neutral and the capacitance required across each phase to obtain unity p.f. in each line. 58.04 A, 69.4 A, 61.08 A, 35.8 A, 300 µF, 28.46 µF, 505 µF

Example 5. A 3-phase 4-wire 400/231 volt, 50 Hz system has a balanced 3-phase motor load of 20 kW at a power factor 0.8 lagging and 1-phase loads 25 A at unity p.f., 45 A at p.f. 0.9 leading and 25 A at p.f. 0.8 lagging, the phase sequence being in the order given. Determine the current in each line and neutral and the capacitance required across each phase to obtain unity p.f. in each line. 58.04 A, 69.4 A, 61.08 A, 35.8 A, 300 µF, 28.46 µF, 505 µF

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 3.31P

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