A load Z draws 12 kVA at a power factor of 0.856 lagging from a 120-V rms sinusoidal source. Calculate: (a) the average and reactive pow- ers delivered to the load, (b) the peak current, and (c) the load impedance. Solution: (a) Given that pf = cos@=0.856, we obtain the power angle as # = cos¹ 0.856 = 31.13°. If the apparent power is S = 12,000 VA, then the average or real power is P = S cos0= 12,000 x 0.856 10.272 kW =

A load Z draws 12 kVA at a power factor of 0.856 lagging from a 120-V rms sinusoidal source. Calculate: (a) the average and reactive pow- ers delivered to the load, (b) the peak current, and (c) the load impedance. Solution: (a) Given that pf = cos@=0.856, we obtain the power angle as # = cos¹ 0.856 = 31.13°. If the apparent power is S = 12,000 VA, then the average or real power is P = S cos0= 12,000 x 0.856 10.272 kW =

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

Chapter2: Fundamentals

Section: Chapter Questions

Problem 2.11P

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