Electrical Engineering ⇒ Topic : True power
True power. The power which is actually consumed in the circuit is called true power or active power. We know that power is consumed in resistance only since neither pure inductor (L) nor pure capacitor (C) consumes any active power. Now, current and voltage are in phase in a resistance.Therefore, current in phase with voltage produces true or active power. It is the useful component of apparent power.
The product of voltage (I) and component of total current in phase with voltage cos (Φ) is equal to true power i.e.
True power, P = Voltage x Component of total current in phase with voltage
= V x I cos Φ
P = VI cos Φ
It is measured in watts (W). The component I cos (Φ) is called in-phase component or wattful component because it is this component of total current which contributes to true power (i.e. VI cos (Φ)). It may be noted that it is the true power which is used for producing torque in motors and supply heat, light etc. It is used up in the circuit and cannot be recovered
!! OOPS Login [Click here] is required for more results / answer