b) A three-phase supply operating at 400 V 50 Hz is supplying a factory with two loads. Load A is consuming 350 kVA at power factor of 0.72 lagging. Load B is powered by a 260 kVA synchronous motor with a mechanical load of 200 kW. The Loads A and B remain constant and synchronous motor is running at over- excited to achieve the power factor of whole system at 0.92 lagging. Determine: (i) the reactive power of the synchronous motor; (ii) the power factor of the synchronous motor; (iii) whether unity power factor of whole system can be achieved; (iv) the best power factor of the whole system at given loads within the rated conditions; (v) the line current of the whole system under the conditions in part (iv).

b) A three-phase supply operating at 400 V 50 Hz is supplying a factory with two loads. Load A is consuming 350 kVA at power factor of 0.72 lagging. Load B is powered by a 260 kVA synchronous motor with a mechanical load of 200 kW. The Loads A and B remain constant and synchronous motor is running at over- excited to achieve the power factor of whole system at 0.92 lagging. Determine: (i) the reactive power of the synchronous motor; (ii) the power factor of the synchronous motor; (iii) whether unity power factor of whole system can be achieved; (iv) the best power factor of the whole system at given loads within the rated conditions; (v) the line current of the whole system under the conditions in part (iv).

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 2.16P: A single-phase, 120V(rms),60Hz source supplies power to a series R-L circuit consisting of R=10 and...

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