Hi folks.
For last two days I was in the clutches of the HV project and didn't get time to post. Yesterday a friend of mine asked me to post about working of the inductor and capacitor at very high and very low frequency. Thank you Sumit for this opportunity and helping me to make this whole thing a 2 way communication.:)
Well, Let us talk about ideal inductor and capacitor first.
The ideal inductor behaves as short circuit at lower frequencies and open circuit at very high frequencies. It is obvious as the inductive reactance is directly proportional to the frequency of supply. You can understand this as inductance is the property due to which element is able to oppose the change in current flowing through it.
The ideal capacitor behaves as open circuit at lower frequencies and short circuit at very high frequencies. The capacitive reactance is inversely proportional to the frequency of supply. Let us go into the basics of this phenomenon.
Imagine that you have 2 metal plates separated by a dielectric. Say capacitor is charging from 0V. When 1st +ve charge comes on plate 1 it induces equal and opposite charge on plate 2. When 2nd +ve charge comes, it is opposed by the 1st charge and the charge induced by this 2nd will be opposed by charge already present on plate 2. Now 3rd charge will be opposed by 2 charges. So if you carefully observe,
1. Capacitor is opposing unidirectional flow of charges. (This explains it is open for DC).
2.Capacitor tends to saturate for unidirectional flow of charges which is what we call charging of capacitor.
3.The first charge did not face any opposition which explains an uncharged capacitor is SC at t=0+.
The practical inductor has inter-turn capacitance that acts as SC and creates problems at high frequency operation. It exists due to the potential gradient between the windings and air as dielectric. The Aryton windings are used to reduce this (using loosely wound turns- increase d and reduce capacitance).
The practical capacitor has inter-turn inductance due to the circular arrangement of the metal foil and dielectric. This inductance will keep quiet at lower frequencies but take over the capacitive properties at higher frequencies.
So there are complex construction constraints for power capacitors and inductors. In short, Low frequency gives power in hands of capacitor and high frequency gives power in the hands of inductor. In the middle somewhere, our poor champ resistor lies, where resonance takes place. We will talk about it soon.
Thank you for your time and please feel free to leave comments about your views or extra information. You can mail me at dnachiketa1010@gmail.com
For last two days I was in the clutches of the HV project and didn't get time to post. Yesterday a friend of mine asked me to post about working of the inductor and capacitor at very high and very low frequency. Thank you Sumit for this opportunity and helping me to make this whole thing a 2 way communication.:)
Well, Let us talk about ideal inductor and capacitor first.
The ideal inductor behaves as short circuit at lower frequencies and open circuit at very high frequencies. It is obvious as the inductive reactance is directly proportional to the frequency of supply. You can understand this as inductance is the property due to which element is able to oppose the change in current flowing through it.
The ideal capacitor behaves as open circuit at lower frequencies and short circuit at very high frequencies. The capacitive reactance is inversely proportional to the frequency of supply. Let us go into the basics of this phenomenon.
Imagine that you have 2 metal plates separated by a dielectric. Say capacitor is charging from 0V. When 1st +ve charge comes on plate 1 it induces equal and opposite charge on plate 2. When 2nd +ve charge comes, it is opposed by the 1st charge and the charge induced by this 2nd will be opposed by charge already present on plate 2. Now 3rd charge will be opposed by 2 charges. So if you carefully observe,
1. Capacitor is opposing unidirectional flow of charges. (This explains it is open for DC).
2.Capacitor tends to saturate for unidirectional flow of charges which is what we call charging of capacitor.
3.The first charge did not face any opposition which explains an uncharged capacitor is SC at t=0+.
The practical inductor has inter-turn capacitance that acts as SC and creates problems at high frequency operation. It exists due to the potential gradient between the windings and air as dielectric. The Aryton windings are used to reduce this (using loosely wound turns- increase d and reduce capacitance).
The practical capacitor has inter-turn inductance due to the circular arrangement of the metal foil and dielectric. This inductance will keep quiet at lower frequencies but take over the capacitive properties at higher frequencies.
So there are complex construction constraints for power capacitors and inductors. In short, Low frequency gives power in hands of capacitor and high frequency gives power in the hands of inductor. In the middle somewhere, our poor champ resistor lies, where resonance takes place. We will talk about it soon.
Thank you for your time and please feel free to leave comments about your views or extra information. You can mail me at dnachiketa1010@gmail.com
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