Modification of LCR Series Equations

Manu Balakrishnan

Abstract: Here I am going to provide a modification for LCR series circuit calculations which have been found to be in agreement with experimental observations. According to LCR series equations, at resonance resistance offered by resistor is the only impedance acting on the circuit.ie, inductive and capacitive elements are absent here. But it is also observed that at resonance we could measure the potential drop across inductor and capacitor. So definitely there is some impedance offered by these circuit elements. The existing LCR series equation fails to explain this. The modified equation can account for resonant frequency, potential drop across inductor and capacitor during resonance and also why the frequency response curves are broader to the right of resonant frequency than to its left. The analysis reveals where we went wrong earlier. The modified equations help us to develop circuits which can be operated on wide range of frequencies.

Keywords: Phase changes in an inductor, Shape of frequency response curve, Impedance at resonance, Resonant frequency, Similarity between capacitor and inductor