If load draws a current of 10A at 0.8 pf lagging when connected in 100V supply calculate the value of real, reactive and apparent powers. Also what will be the resistance of the load?
Answers
Explanation:
along the x-axis, and quadrature phase (Imaginary), yes we use complex numbers here, because it is plotted along the plus (+) and (-) y-axis..
So, you have a total current of 10A. This is a vector line starting at x=0, y=0 and extends out 10 units to represent 10A. Now you need to determine the angle. This is obtained from the Power Factor(PF). Having a PF = 0.8, the x-axis value is PF × 10A. Now plot this value along the x-axis. Now rotate your 10A vector down because you have a lagging PF, until it's projection into the x-axis matches the Real part previously plotted. Now you have a Rt triangle. The hypotenus is the magnitude of the current. The x-axis is the in-phase current and the height from the x-axis is the 90° out of phase reactive current. Knowing this, you can calculate
The magnitude of the total current
The real part or resistive current
The reactive current.
The phase angle of the total current from the resistive current
You can now do this elementary calculation using the Rt triangle theorem.
hope it will be helpful to you