I am given a balanced 3 phase circuit question shown in the linked image. I am confused on the difference between apparent, average and reactive power and how each is calculated. This is my first post so I hope it is in accordance with the rules. Thanks
Electronic – Calculate total apparent, average and reactive power in 3-phase
powerthree phase
Related Topic
- Apparent power definition
- Electronic – Calculating reactive power (Q) sign
- Electronic – Three phase system – power factor
- Electrical – why we say that in three phase system total power delivered to the balanced three-phase circuit is the same at any instant
- Reactive Power – Does Reactive Power Flow Between Energy Storage Elements in a Three Phase System?
- Electrical – Effect of Reversed Phase Polarity on Active & Reactive Power of 3-Phase System
Best Answer
Average power is the real power you get billed for as kWh and, is the numerical multiplication of voltage and current waveforms, often done in an MCU these days but back in the old days a thing called a wattmeter did things magnetically then, along came analogue multiplier chips and solid state magnetic multipliers as patented by Landis & Gyr. This is all about four quadrant multiplication of the instantaneous signals and not to be confused with either of the following: -
Apparent power is RMS voltage x RMS current and only equals average power (above) on a purely resistive load. For pure sinewaves: -
\$Power_{Average} = Power_{Apparent}\cdot Power\space Factor\$
i.e. \$P=V\cdot I\cdot Cos{\phi}\$
Where power factor is the cosine of the phase angle between voltage and current - clearly when that angle is zero, power factor = 1.
Reactive power is \$\sqrt{Apparent^2 - Average^2}\$: -
See also this site for further details.