I know the impedance of the inductance is: 'jwl'; but this is correct with sinusoidal input; now my question is:
how to calculate the impedance when the input is the periodic square wave(like a digital clock)?
any help will be appreciated.
Electrical – how to find impedance of inductance with square wave input
circuit analysisimpedanceinductorsquare
Best Answer
You could use the fundamental to get a very approximate stab, but because a square wave has significant energy at higher frequencies, there will be a fair degree of error.
However, given that we know that the square wave is treatable as a summed series of sine waves with a well known equation - you could iterate towards a better solution by applying the sine wave equation for impedance at each of these harmonics in turn, and summing the current flowing at each. You then get a series of sinusoidal currents which you can sum to get total current, and then get impedance back.
As you include more and more of the upper frequencies you will iterate towards a more accurate solution. This could be done easily enough in a spreadsheet or with a simple script if you know a little programming.
This gives a decent solution without delving into higher mathematics - or a useful sanity check on results that you might obtain by other methods.