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Unfortunately the frequency legend on your graphs are too small to see, so we don't know how the left and right graphs relate to each other. However, what is certainly going on in the left graph i...
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#2: Post edited
by
Olin Lathrop
·
2022-05-31T15:18:12Z (over 2 years ago)
- Unfortunately the frequency legend on your graphs are too small to see, so we don't know how the left and right graphs relate to each other.
- However, what is certainly going on in the left graph is a LC resonance. Again, it would be useful to know where that peak is in relation to the right graph. If it's way over to the right, then that shouldn't be too surprising.
- Adding more capacitance should in theory lower the impedance everywhere. However, phase shifts also occur. Put another way, when you are getting near the non-ideal behavior of the capacitors, you have to consider the complex impedances and how they combine in the complex plane.
- Something that might help with intuition is to consider an ideal parallel LC circuit. Looking at just the capacitance, the impedance magnitude goes steadily lower with higher frequency. However, put the inductor in parallel with it and you suddenly have infinite impedance at one particular frequency.
By adding capacitance in your example, any resonant frequency due to non-idea characteristics will get lower. It can then show up at a frequency where there was previously no peak.
- Unfortunately the frequency legend on your graphs are too small to see, so we don't know how the left and right graphs relate to each other.
- However, what is certainly going on in the left graph is a LC resonance. Again, it would be useful to know where that peak is in relation to the right graph. If it's way over to the right, then that shouldn't be too surprising.
- Adding more capacitance should in theory lower the impedance everywhere. However, phase shifts also occur. Put another way, when you are getting near the non-ideal behavior of the capacitors, you have to consider the complex impedances and how they combine in the complex plane.
- Something that might help with intuition is to consider an ideal parallel LC circuit. Looking at just the capacitance, the impedance magnitude goes steadily lower with higher frequency. However, put the inductor in parallel with it and you suddenly have infinite impedance at one particular frequency.
- By adding capacitance in your example, any resonant frequency due to non-ideal characteristics will get lower. It can then show up at a frequency where there was previously no peak.
#1: Initial revision
by
Olin Lathrop
·
2022-05-31T15:13:39Z (over 2 years ago)
Unfortunately the frequency legend on your graphs are too small to see, so we don't know how the left and right graphs relate to each other. However, what is certainly going on in the left graph is a LC resonance. Again, it would be useful to know where that peak is in relation to the right graph. If it's way over to the right, then that shouldn't be too surprising. Adding more capacitance should in theory lower the impedance everywhere. However, phase shifts also occur. Put another way, when you are getting near the non-ideal behavior of the capacitors, you have to consider the complex impedances and how they combine in the complex plane. Something that might help with intuition is to consider an ideal parallel LC circuit. Looking at just the capacitance, the impedance magnitude goes steadily lower with higher frequency. However, put the inductor in parallel with it and you suddenly have infinite impedance at one particular frequency. By adding capacitance in your example, any resonant frequency due to non-idea characteristics will get lower. It can then show up at a frequency where there was previously no peak.