EEE 3230 POWER SYSTEM ANALYSIS 8 Lecture 9: Power Factor Sezai Taskin, Ph.D. sezai.taskin@cbu.edu.tr

9 Power Factor The power factor (p.f.) is computed based on the phase angle between the voltage and current where the voltage is the reference phase. is also the angle of impedance

9 Power Factor Therefore, the power supplied by a power source to an inductive load can be expressed as: As can be seen from the above defi nition, an inductive load will have a lagging p.f. Therefore, the power source supplies reactive power to the load. The reactive power supplied by the source is consumed by the inductive load. This can also be expressed as:

Now let us look at an R – C circuit 9 Power Factor Now let us look at an R – C circuit

9 Power Factor Therefore, for a capacitor load, the current through the capacitor leads the voltage. The power supplied by the AC source can be expressed as: The capacitive loads will supply reactive power to the source. We can also write the complex power as:

9 Power Factor

9 Power Factor

9 Power Factor

9 Power Factor