Answer / gopal

actually here we are dealing with phasors in AC system .and
Vs and Vr are equal in magnitude but not in phase angle.
power flows from Vs/_ᵟ to Vr/_0 according to the equation of
real power flow
P= Vs Vr Sin(ᵟ) Vs/_ᵟ - Vr/_0
------ = ---------------
Xs I
actually in phasors although their magnitude is equal but
still their difference is not zero and an appriciable
voltage difference exist between the two ends which trigger
current and hence power to flow,

Answer / akash kumar

actually for the transfer of active power in a ac transmission system you need phase difference between the Vs and Vr.a line loaded with its own surge impedance acts as of reactive nature only.its reactive power requirement is supplied by its own line capacitance.thus no reactive component of line current and hence highest ohmic current in the line!!!


P=(Vs*Vr/X)Sin(delta)

Answer / muhammad ismail

Actually you are asking about Vs and Vr and PD.
On load side there is always ZERO Potential thats why power
flows to receiving side in line.

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