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A three phase unbalanced four wire star connected system can be analysed usinga.Millman's theoremb.star delta transformation methodc.loop current methodd.all above methods

Question

A three phase unbalanced four wire star connected system can be analysed usinga.Millman's theoremb.star delta transformation methodc.loop current methodd.all above methods

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Solution

The analysis of a three-phase unbalanced four-wire star connected system can be done using all the methods mentioned above. Here's a step-by-step explanation:

a. Millman's Theorem: This theorem is a method to simplify the analysis of electrical circuits. It is used to calculate the voltage output of a circuit with multiple sources of voltage and resistance. In the context of a three-phase unbalanced four-wire star connected system, Millman's theorem can be used to simplify the analysis

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A balanced three-phase star-connected supply of phase sequence ABC feeds a balancedstar connected load of impedance 5025°Ω in each phase. Phase voltage of Phase A ismeasured to be 24030° V.a) Determine the magnitude and phase of each line current supplied by the source.b) Determine the active power and the reactive power supplied by the source.c) Determine the reactive power requirement of each of the three capacitances,connected in star, to improve the power factor to 0.95 lag.

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