Answer:
Complex analysis = 682.2 V
Explanation:
1. Using a complex power approach:
Data:
Power drawn by the load, Q load = 120 kW
Power factor lagging = 0.85
The reactive power is solved as follows:
tan [arccos (power factor)] = [tex]\frac{Qload}{Pload}[/tex]
tan (cos⁻¹ [0.85]) = [tex]\frac{Qload}{120}[/tex]
solving the equation above gives Qload = 74. 4 kVar
The complex power drawn in by the load is given as:
S load = P load + jQload
= 120 + j74.4 kVA
using the complex analysis above, we can solve for the current into the load like this: I = [tex]\frac{Sload}{Vload}[/tex]
= [tex]\frac{120 + j74.4}{480/8}[/tex]
= 294 (-31.8⁰) A
The power factor will be 682.2
2. Circuit power approach:
using the KVL:
Vsource = Zline + Vload
= j 1(294 (-31.8⁰) + 480
= 682.4
The power factor will be cos (21.5 - 31.79) = 0.598 lagging
