Voltage regulation under a capacitive load.

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Homework Statement

Why does the voltage regulation of a transformer become negative when a capacitive load is attached? It causes the voltage across the secondary winding to increases rather than decrease, as would be the case for a resistive load. But why?

Homework Equations

Regulation = (Vn-V)/Vn

where Vn is the voltage at no load

The Attempt at a Solution

As I understand it, the capacitance is obviously reactive and consumes no power, instead it reflects the power back to the source, and this results in an oscillation of power.

I'm probably missing something obvious here, but the negative voltage regulation can't be due to the returning power from the capacitance increasing the voltage?

 

[DaveE]

Yes, you're on the right track with your statement "this results in an oscillation of power". To learn more look into "resonant circuits" and "simple harmonic oscillators". Like pushing a child on a swing, if you do it at just the right time, you can build up a big response.