(b) The unbalanced four wire Y-connected load has balanced voltages of 415 V and the RYB-sequence. By taking VRN as reference, with the load impedances are ZR = 25 2, Zy = (20 +j15) Q, Z (40-j30) 2. (i) Sketch the three-phase circuit with three wattmeter connection to measure the real power in the system, (ii) Calculate the line currents and neutral currents. (iii) Calculate the wattmeter readings and find the total power absorbed by the load. (iv) Can two-wattmeter method be used to measure the real power for the system ? Justify your answer. UTM

(b) The unbalanced four wire Y-connected load has balanced voltages of 415 V and the RYB-sequence. By taking VRN as reference, with the load impedances are ZR = 25 2, Zy = (20 +j15) Q, Z (40-j30) 2. (i) Sketch the three-phase circuit with three wattmeter connection to measure the real power in the system, (ii) Calculate the line currents and neutral currents. (iii) Calculate the wattmeter readings and find the total power absorbed by the load. (iv) Can two-wattmeter method be used to measure the real power for the system ? Justify your answer. UTM

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 2.52P: A balanced three-phase load is connected to a 4.16-kV, three-phase, fourwire, grounded-wye dedicated...

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It is stated that (i) balanced three-phase circuits can be solved in per unit on a per-phase basis after converting - load impedances to equivalent Y impedances. (ii) Base values can be selected either on a per-phase basis or on a three-phase basis. (a) Both statements are true. (b) Neither is true. (c) Only one of the above is true.
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