Paul A. Cianciolo wrote: > > Hello Folks, > > First I must apologize because this is off topic. I will try > to keep it short. > > The other day I had a phone conversation with Otmar about a > problem I am have with a wind power generating system I am > building. He was very helpful and described a simple circuit, > with part numbers on how to build a charge pump voltage > converter to regulate the varying voltage from the wind > generator(which all homemade) to the charge voltage needed for > the 48 volt 500 amphr battery pack. > > I have spent more than a few hours looking on to find circuit > information on this but the generator is working in the > kilowatt range and I have found nothing yet. > > Could someone please help me here. I hate to bother Otmar > again but I have the lost the paper the notes were on. > > Generator voltage can fluctuate from say 40 Volts at 120 RPM > to 250 or more at 650 RPM Max RPM > > Thank you for any help and again sorry to be off topic > > [EMAIL PROTECTED] > > Paulc > W1VLF
Hi Paul, well, to do this properly you need a "cube law" converter which will match the charge current properly to your wind speed. I happen to be working on something like this. You say 250V at 650RPM - that's very fast for a direct drive wind turbine, so I assume you have some gear-up. So if with any decent wind speed your generator voltage is >= 48V, what you actually need is a buck mode connverter, even a fixed duty cycle PWM would do something useful. If the generator output is AC, try experimenting with a tap- changing transformer to see exactly what you need. You will likely find that the best compromise is a simple fixed transformer ratio - the blades will go into stall above that speed. If it is a permanent magnet DC generator, then you should try a chopper circuit as above. Regards, Evan.
