#### Salvador12

##### Full Member level 4

Say you have a small capacitance , from somewhere of 500 pF upwards to maybe 500 nF maybe p to 1 uF at best.

Now say I wish to transfer AC current through it , for example , at 50 Hz.

Now for a series LC circuit the circuit becomes purely resistive at resonance when the L and C reactances are equal.

So in theory at resonance I could transfer most current, but the problem is that for such a small capacitance the resonant inductance is very large which means a large coil made of rather thin wire in order to achieve that resonance.

So even if the circuit becomes purely resistive , due to the large coil the DC resistance of that cold would be substantial and limit maximum current.

So what I'm asking is , how does one achieve efficient power transfer if one only has small capacitance? Parallel LC? There too the coil still have to be massive due to the need for maximizing inductance as far as I'm aware.

One option is to increase frequency, in the hundreds of kHz range even a small capacitance can transfer alot of power and it's reactance is small, but what if I wish to do it at low frequency ?

The only option that comes to mind is to increase voltage because as far as I know for the same capacitance , increasing voltage increases the total energy either stored in the capacitor as in DC or transferred through the capacitor as in AC.

Any comments folks?

Thanks.