What is power factor significance in calculating the AC power?

Answer 1

Power Factor is one of most significant parameter in calculating AC Power. As we know it is cosine of angle between AC Voltage and Current it comes in picture while calculating power in AC circuits Power In AC (P) = Voltage (V) X Current (V) X Power Factor

Let us take an example of Power with Power factor and without power factor for same circuit.

Let Us assume

V = 125 Volts

I = 1 Amp

Power Factor = 1

Then

P = 125X1X1= 125 Watts

But for any circuit when Power factor is below 1, to execute same power, Circuit has to draw more current. for example

P = 125X 1.25 X 0.8 = 125 Watts

In first example power factor of the circuit was unity = 1 and in that condition current of the circuit was 1 amp whereas in second example power factor of the circuit is 0.8 due to which current of the circuit increases to 1.25 amp to execute the same power. Now due to increase in current of the circuit many factors are affected like heat loss, Conductor's specification , Class of insulation etc.

Thus it can be concluded after going through above explanation that power factor play a significant role in AC power calculation as well as in actual practices.

Answer 2

As the name implies, these are calculations to determine the power factor of a load, where power factor is the ratio of a load's true power to reactive power.