# charging capacitor

Discussion in 'General Electronics Chat' started by TAKYMOUNIR, Feb 10, 2012.

1. ### TAKYMOUNIR Thread Starter Active Member

Jun 23, 2008
351
1
there is high voltage power supply (very high voltage up to 100 kv) we use it for charging capacitors, my question why we do not use the power supply direct to do the function of the capacitor if not(i mean we can not use power supply instead of capacitor) why we use the capacitor,and what kind of application that use the capacitor with very high voltage charge
thanks

Feb 16, 2010
112
5
I'm not sure what you're saying. Do you mean that you charge up the capacitor with the 100 kV and then turn of the source and allow the capacitor to power a circuit?

Otherwise the capacitor is probably just across the source to smooth out the supply. The source still supplies the power and the cap just shunts away high frequencies.

EDIT: Also, if you're just charging the cap, do you move it into a circuit to use it later? I imagine it would be difficult to safely take the cap from the source and make a circuit with it.

Last edited: Feb 10, 2012
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3. ### ErnieM AAC Fanatic!

Apr 24, 2011
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There are two reasons off the top of my head why to use a cap:

The cap may be used to get an instantaneous bust of current far larger then the power supply is capable of.

The cap absolutely limits the total energy to about (.5*C*V^2)

As far as typical applications such as these, the ones I am familiar with are for electrostatic discharge (ESD) testing where a capacitor C is charged to a certain voltage and discharged into something under test thru a resistor R to simulate a human finger zapping something.

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4. ### TAKYMOUNIR Thread Starter Active Member

Jun 23, 2008
351
1
thanks very much you got what in my mind

5. ### holnis Member

Nov 25, 2011
50
4
Basically, when we have a system and have a high power surge from bass, like the brief hard hits, the capacitor let's loose some energy to compensate and help save the battery. very quick. then charges back up.

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6. ### BillB3857 Senior Member

Feb 28, 2009
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348
Sounds similar to a photo flash system. Low current high voltage source charges a cap and the cap provides a high current surge to the flash tube.

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