Disclaimer: Hi, I was in the neighborhood (StackOverFlow) and just noticed this cool site. I have had this general wondering for a while now and I am not sure if my question is constructive enough for this site (not from EE background). But I am genuinely interested to learn/know if there's any practical use of the concept. So, please do keep an open mind and any explanation would be greatly appreciated.
Concept: Let's say I have a DC motor (12V, 0.5A) and I managed to keep it spinning by "strategically" attaching some neodymium magnets around it (my intention is not to start a war regarding whether or not it is possible, but for the sake of practical usage, let's assume it is possible). The output I am getting is 7-9V, unknown amperage.
Question: Is it possible to convert this variable output to a stable 5.0 volt (standard USB output) with 0.5-1.0 amp to charge cellphone and if so, could anyone please provide some resources / explanation / diagram?
Assuming we can completely ignore the laws of physics, especially as regards conservation of energy, then yes it is possible*.
The device you are looking for is called a "Voltage Regulator", and it takes in a variable voltage and outputs a stable, lower, voltage.
They come in two basic flavours:
Now the electronics are sorted out, why not head over to Physics.SE and discuss perpetual motion and why it doesn't work in the real world. :)
* for certain values of "possible"