I've been taught that a transformer only works with AC, however I see that in power converters, it is rectified to a DC voltage before going to the transformer. How does that work?
If the rectified AC waveform is now DC, how does it pass through the transformer? Is the rectified signal still good enough for the transformer, because it still has a fluctuating component in it, just not negative anymore?
So for example, if I have a 230V mains (with 10% fluctuation) going into my rectifier, the output DC level will range from 293V to 358V. Is this fluctuation/AC component good enough to pass through the transformer?