I have a single phase mains supply which I need to split it into two phases, then shift one of them by 90 degrees relative to the other (with peak values of both waveforms having the same magnitude).(adsbygoogle = window.adsbygoogle || []).push({});

I know this is generally done by two branches in parallel, with a series capacitor in one of the branches and a series resistor in the other. As I see it, the magnitude of the capacitive reactance (Xc) in the one branch and the resistance (R) in the other have to be the same if the magnitudes of the two waveforms are to be the same

i.e. |Xc| = | 1/(2*pi*freq*C) | = |R|

Is this a correct assumption?

I know that for this application, a paper capacitor is the best option. If my mains supply is 230V 50Hz, does anyone know how I go about finding the required series capacitance and it's rating? None of the text books I have access to explain this topic in any detail. Also, everything I've found seems to suggest that a capacitor automatically sets up a phase shift of 90 degrees (which may only be the case for an "ideal" capacitor). Any advice or suggested online resources would be greatly appreciated.

Thanks in advance

Jack

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# Homework Help: Phase shift using a series capacitor

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