I'm doing a university project and we're not allowed to use mains. Hence, I planned to use a 9V input and step it up to 24V.
However, I couldn't find any transformers online which have a 9V ac input; all I found are designed for mains (220V/110V).
I'm using a switch mode circuit to convert the 9V dc to 9V ac, then step it up to 24V ac and use a rectifier circuit to convert it back to dc.
So my question is what will happen if I bought a 80Vac "input" to 24V ac "output" transformer and used a 9V ac as the input?
I know the voltage will lower in the secondary because the voltage is much lower in the primary. If that is so, how can I calculate the difference?
Also, I'm using a voltage regulator (0 to 40V input) -> (24V output) after the rectifier circuit. Any solutions? Thanks in advance.
Best Answer
If a transformer is rated for 80 V in and 24 V out, then its output will be 24/80 = 30% of its input for any input that doesn't saturate the core. Therefore, 9 V in will yield 2.7 V out.