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Anonymous Poster #1

Reactive Power?

04/01/2011 1:04 PM

how does a capacitor generate reactive power....?

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#1

Re: reactive power?

04/01/2011 2:41 PM

It doesn't.

It stores power and releases it in response to a lack of it, so it ends up compensating for a lack of reactive power. But it does not actually "generate" anything that was not supplied to it.

Excerpt from this website, a pretty good place to learn the basics.

"Reactive power (KVARS), caused by inductive loads, always acts at a 90-degree angle to working power (KW).

Inductance and capacitance react 180 degrees to each other.

Capacitors store KVARS and release energy opposing the reactive energy caused by the inductor.

The presence of both a capacitor and inductor in the same circuit results in the continuous alternating transfer of energy between the two. Thus, when the circuit is balanced, all the energy released by the inductor is absorbed by the capacitor."

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#3
In reply to #1

Re: reactive power?

04/02/2011 2:26 AM

from where it is getting reactive power...?..it is source or anything...? or it coverts the active power into reactive power by storing it..? it means generate word for capacitor is wrong...?

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Anonymous Poster #2
#4
In reply to #3

Re: reactive power?

04/02/2011 8:54 AM

Almost exact replica of the capacitor is a flywheel or a reservoir.

They do not generate energy.

While rotation the flywheel takes some energy from prime mover (or the reservoir from pump) and stores inside them and releases that energy back when there is a requirement from load. The same principle works with Capacitors.

The capacitors and inductors are only used to store energy ane release when there is a demand (and ideally there is no loss in them)

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#2

Re: Reactive Power?

04/02/2011 1:50 AM

Capacitors do not generate reactive Powers. Actually, Capacitor (formerly known as condenser) is a device for storing electric charge.

Capacitors are used in variety of applications like "Energy storage, Power conditioning, Noise filters, Snubbers signal Processing, Power factor correction, etc".

Generally, Capacitors rating used Power factor correction are given not in farads but rather as a reactive power in volt-amperes reactive (VAr).

The main purpose is to counteract inductive loading from devices like electric motors and transmission lines to make the load appear to be mostly resistive.

Individual motor or lamp loads may have capacitors for power factor correction, or larger sets of capacitors (usually with automatic switching devices) may be installed at a load center within a building or in a large utility substation.

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#5

Re: Reactive Power?

04/04/2011 10:39 AM

It follows the description given in Wikipedia.

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#6

Re: Reactive Power?

04/06/2011 6:15 AM

A capacitor would never "generate" reactive power. Conversly, it draws recative power.

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