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Infinite Capacitor Voltage

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baby_1

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Hello
as you know this equation
eeb64263325750f08a1e7249b4b88095.png


Capacitor voltage can get more charge while the Current continue.but according this schematic
220px-RC_switch.svg.png


the current decrease by time increase and voltage of capacitor should be equal to source power after the RC period time.

so the voltage can't get more charge to higher voltage.

if we change the Dc power to ac Power capacitor behave as an impedance.and seems can't charge more only transfer some electronic between its plate.

now can charge capacitor with higher voltage with Current?
 

Dear baby_1
Hi
At AC , capacitor will charge , too . it is the cause of it's impedance . it will charge at 1/4 of cycle and will discharge at 1/4 of cycle too . and ...... etc ( + and negative ) . so , the capacitor can't occupy more than supply voltage , unless it will be at a current source , thus it can accept higher charges .
Best Luck
Goldsmith
 
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    baby_1

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Dear goldsmith
how can make a Current source for charge the Capacitor for infinite voltage?
 

Infinite voltage ???!!! it is impossible ! but if you need a current source for very high voltages , you should try to create a high voltage ( nearby some kilo volts ) and then use it as supply of your current source . to achieve high power current source , there are many ways available , that depends on your purpose .
Best Wishes
Goldsmith
 

Yes,i know it is impossible to get infinite.but i want to create a circuit that charge capacitor with current source by time.if i do it with an CE current source it doen't work.now how can i should create current source for low voltage (10 Volt)
 

A coil is the component that will generate as high a voltage as it needs to, in an attempt to sustain current flow when resistance suddenly goes high. It may even produce a spark, the voltage can get that high.

So mathematically speaking the coil might be said to generate near-infinite voltage.
 

Hi Baby_1,

If you want a current source that gives you high voltage you should check out boost converters. They utilize a coil to work as a current source, that can raise voltage to high values (limited by the insulator thickness etc for discharge and leakage currents on coil and other PCB elements). That would mean that ideal components would raise the voltage to infinity.

Infinite voltage has not yet been achieved though, but good luck in trying :D
 
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    baby_1

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Thanks Sloth
could you attach a boost convertor.because i want to analyses it and know how they works and theory of them
 

Thanks for everything
i will read them after my exam and if i have any question once again i ask you more and learn more.
thansk
 

Hello
i has read "http://en.wikipedia.org/wiki/Buck_converter" article but it shows me that the Energy from inductor transfer to Capacitor.but i want to know how can we charge a capacitor with a Current source.
Any help appreciate
 

If you connect a current source to a capacitor then the current source will charge the capacitor.

Which part of that don't you understand?
 

as you know if create a Current source with transistor and put the capacitor as load it only charge until Vc=VEE,doesn't take more voltage.
i want to demonstrate the capacitor integral voltage the increase with Current
 

baby_1 said:
as you know if create a Current source with transistor and put the capacitor as load it only charge until Vc=VEE,doesn't take more voltage.
i want to demonstrate the capacitor integral voltage the increase with Current
Click to expand...

Yes, that happens because no current source (or anything else) is a perfect. You may build a "perfect integrator" (that is what you want) in a limited domain.

Check this circuit:

https://bertrik.sikken.nl/bat/pix/funcgen.gif

The op-amp at your right is a perfect integrator... until the output clips! It will integrate the voltage that the left op-amp outputs. The whole circuit is a simple oscillator: the op-amp at the left is configured as a schmitt-trigger and outputs a square wave. The right op-amp is the perfect integrator: it will integrate a positive voltage as an ascending ramp and a negative voltage as a descending ramp. The schmitt-trigger toggles depending upon the voltage of the perfect integrator, assuring this last one is always working on its domain.
 

Dear baby_1
Hi again
can you tell me that what do you want to do , exactly ? perhaps there are better ways ( better than charging a capacitor !!!!) available . if you tell us a bit more about the aim of this project perhaps we can help you as well as possible . unless it is a hobby . and not for any specific aim ?
Best Luck
Goldsmith
 

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