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Join this group to post and comment. ericsson • Jan 19, 2009

# How to calculate power in capacitor?

How to calculate the power consumed by a capacitor which is connected to a line to improve powerfactor? vasanthmbs • Jan 21, 2009
p=i^2(Xc)..
Xc=1/2pifc ericsson • Jan 24, 2009
The formula u have given is used to calculate the reactive power only. what we have to do to calculate the real power.....? icehari • Jan 24, 2009
basically capacitors don't consume power, they store the power and release the power when a predetermined level is reached, But i have no idea to calculate the power consumed by capacitor.. reachrkata • Jan 27, 2009
No capacitors have pure capacitance, there is always a resistive component. If that is what you require, you can refer the datasheets to get the resistance value and use that to calculate the power dissipated.

- Karthik avm • Jan 30, 2009
Pure capacitors and inductors do not consume power. The power assosiated with these are only reactive power unless there is some internal resistance. If there is some internal resistance, it will consume power. mimo11 • Feb 3, 2009
Capacitors stores energy only and discharge it after voltage drop under a limit

you can calculate energy stored in capacitor using this law C* V^2

where C : capacitance of the system
V : voltage applied gargoor • Feb 4, 2009
ideally , all the energy stored in capacitor during the positive portion of the power cycle is returned to the source during the negative portion, no net energy is lost due to conversion to heat in capacitor , so the true power is zero , actually because of the leakage and foil resistance in a practical cpacitor , a small percentage of the total power is dissipated in the form of true power ..
u can just calculate the reactive power wich is the rate at wich capacitor stores and returns energy . so its not zero , bcz at any instant in tme the capacitor is actually taking energy from the source or returning energy to it
P = V*I
P=V^2/ Xc
R=I^2 * Xc