(a) Based on the relationship between the line and phase value of currents and voltage, show that the active power input to a three-phase balance load is V3VIcosø, where V and I are line quantities. (b) A balanced Y-connected load has phase voltage of 230 V and positive phase sequence. The impedances Za, Zs, and Zc are 10230° N, respectively. (i) By taking Vas on the load side as a reference, determine all the line currents and phase voltages and line voltages. (ii) Determine total real power, P, total reactive power, Q and total apparent power, S of the system. (iii) Total real power of the loads can be measured using two wattmeter methods. Draw the connection of the two wattmeters if their current coils are in line A and C, respectively. What is the total real power measured by each wattmeter? Prove and compare the value with Q2(b)(i11).

(a) Based on the relationship between the line and phase value of currents and voltage, show that the active power input to a three-phase balance load is V3VIcosø, where V and I are line quantities. (b) A balanced Y-connected load has phase voltage of 230 V and positive phase sequence. The impedances Za, Zs, and Zc are 10230° N, respectively. (i) By taking Vas on the load side as a reference, determine all the line currents and phase voltages and line voltages. (ii) Determine total real power, P, total reactive power, Q and total apparent power, S of the system. (iii) Total real power of the loads can be measured using two wattmeter methods. Draw the connection of the two wattmeters if their current coils are in line A and C, respectively. What is the total real power measured by each wattmeter? Prove and compare the value with Q2(b)(i11).

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 2.44P: Two balanced three-phase loads that are connected in parallel are fed by a three-phase line having a...

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