Need a boost converter circuit.

[gizmo]

Hi all

I've just put up a little windmill using one of those 24v 300watt DC motors from www.oatleyelectronics.com. Made a set of PVC blades with a tip ratio of 7. And it goes like the clappers. Shorted output current was 12 amps, but voltage only peaked at 6 volts. As these are a DC motor I cant use a transformer to step up the voltage, so a boost converted is needed.

Has anyone come across a simple boost converter circuit that would give an output over 13 volts for charging 12 volt batteries, and with a variable input voltage, say 3 to 10 volts, and can handle this sort of current.

Thanks in advance.

Gizmo

www.thebackshed.com

[commanda]

Might have to build one. Only one I've seen commercially is from Jaycar, cat AA-0264. Max output current is only 2 amps though.

What sort of power level were you hoping to get out of it?

Amanda

[gizmo]

Hi Amanda.

Not expecting much. As the motor is so cheap ($36) and the whole windmill took less than 2 hours to make, including blades, I would be happy with 2 amps charging current. I'll have a look at that Jaycar unit. The windmill is running very well in low wind and starts easily as there is no cogging, so it could be a good little windmill in light winds, as the big F&P windmill wont start untill the wind picks up.

Thanks for that.

Glenn

[sPuDd]

Linear Technology (LT)

http://www.linear-tech.com/pc/productDetail.do?navId=H0,C1,C1003,C1042,C1031,C1061,P1313

This LT1170 5 pin IC with a few external components scrapped from an

old computer PSU can deliver the goods. It will start at 3V and go as

high as 60V input - perfect for wind. I use them to charge batts from

those tiny 0.45V solar cells. 10 cells gives about 3-4.5V and the cct

starts easily and produces very clean power. I have even tried them

without a heatsink and they seem quite robust.

sPuDd..

[DanG]

w-s booster here!!

[veewee77]

years ago, Radio shaft had a 6Volt to 12V converter that was made so you could run a 12Volt car radio in a 6Volt car.  Or, the same device could be used to change from a 12V positive ground to a 12V negative ground.

One of these would take your 6V and boost it to 12V, but remember, if you just used a meter with no load when you tested the voltage, soon as you put a load on it, the voltage will drop considerably.

I think those were rated at 3A outout when converting from 6 to 12V.

I have a couple of them around here somewhere that still work. . .

Doug

[drdongle]

what, no inverter schematic??

[BruceDownunder]

Hi Glenn., Silicon Chip mag ran an item in July 1996 on a 2A charger but you also get the instructions for boosting it to 3.5 A.

Oatley electronics sell the kit K091-S01

Bruce