B Series LC frequency/voltage dependance

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I think I have mistaken something here but does changes in voltage affect the frequency of a series LC or parallel LC circuit or not?
Or is the frequency only dependent on capacitance and inductance of the circuit elements?

And if the fed in frequency matches the resonant frequency then the LC circuit reactance drops to zero ohms and only the ohmic wire resistance is left right?
 

berkeman

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I think I have mistaken something here but does changes in voltage affect the frequency of a series LC or parallel LC circuit or not?
Or is the frequency only dependent on capacitance and inductance of the circuit elements?
That depends. As long as the increase in amplitude of the voltage waveform does not cause an increase in current levels that result in saturation of the inductor (or cause some other non-linear effect), then the resonant behavior of the LC circuit will not depend on the amplitude of the voltages involved. Do you think you have observational evidence to the contrary?
And if the fed in frequency matches the resonant frequency then the LC circuit reactance drops to zero ohms and only the ohmic wire resistance is left right?
What reading have you been doing to answer this question? You could use a simple Google Images search to help you see the impedance of series and parallel LC circuits, for example.
 
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Ok, my bad , quick search reminded me that it was the series LC that had the least impedance as it approached it's resonant frequency while the parallel LC did exactly the opposite. Lucky for me my case involves the series LC.
I don't have any observational experience but part of what I'm making involves a series LC which would ideally have to hold it's frequency constant over a range or voltage/current values, ideally I should only be able to control the frequency with the help of the capacitor.

Think of the inductor in my case like a transformer winding and the capacitor being in series with it, now the strength of flux around my winding will change so the voltage in the winding and current will most likely change over some range but the circuit itself should be set so that it resonates with a certain frequency. The good thing is that my core flux is directly linked to my series LC resonant frequency whatever it will be.
 

berkeman

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part of what I'm making involves a series LC which would ideally have to hold it's frequency constant over a range or voltage/current values
Then you need to ensure that the inductor does not get close to saturation at the highest excitation levels. You may need to make it a bit oversize (bigger core area, lower mu material) to ensure that.
 

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