This is another example of 'not wanting to start from here' - treat it as a theoretical exercise if you will, but the fixed doll's house application I'm starting with can't change, so there is little point in suggesting that...
We are looking at a (very) small wind turbine generator which will be spinning a brushless motor from a disk drive. Such a set-up will probably spin at 300rpm for much of the time, and this will generate a voltage of perhaps 0.5v at perhaps 5mA. So...0.0025VA. And I would like to make that do some useful work - perhaps charge a battery (which is 12v).
I had thought of taking A/C off the motor into a transformer (probably small audio) to bring it up to 12v, with a rectifier on the output which would give DC, and stop the battery charge leaking away. But I see various clever circuits around on the Web - which I suspect won't work with such a low input voltage. Has anyone got any better ideas? Apart from giving up, that is....
P.S.
I've just spun one of the motors, giving 0.7v at 100mA. A bit better than I thought, but still pretty minimal for Power Electronics...
We are looking at a (very) small wind turbine generator which will be spinning a brushless motor from a disk drive. Such a set-up will probably spin at 300rpm for much of the time, and this will generate a voltage of perhaps 0.5v at perhaps 5mA. So...0.0025VA. And I would like to make that do some useful work - perhaps charge a battery (which is 12v).
I had thought of taking A/C off the motor into a transformer (probably small audio) to bring it up to 12v, with a rectifier on the output which would give DC, and stop the battery charge leaking away. But I see various clever circuits around on the Web - which I suspect won't work with such a low input voltage. Has anyone got any better ideas? Apart from giving up, that is....
P.S.
I've just spun one of the motors, giving 0.7v at 100mA. A bit better than I thought, but still pretty minimal for Power Electronics...
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