* Constructed the new wind turbine rectifier unit
The original temporary one got so hot last weekend with all the strong, prolonged wind,
I was concerned the diode bridges would fail with catastrophic effects.

Thanks to David (who gave me a whole tray of once-used CPU coolers and fans), an idea of
how to best build the new one quickly developed. They have a lovely copper heatsink,
bonded to a reasonably sizable aluminium fin assembly, with a small fan.

Testing shows these fans start to work at about 4V, and survive at least briefly at 30
volts, so since my turbine makes about 60 volts at peak when 2-phase half-wave rectified,
3 fans in series should be quite happy.

I've put one rectifier per heatsink, and joined BOTH AC inputs together to give me two
diodes in parallel for each half-cycle, per phase. Nominally 35A rated bridges, this gives
me some safety margin.

An old 6.6Mb floppy disk drive enclosure makes a great box. It's diecast aluminium so it
is strong, will dissipate heat well, and won't burn or melt! Plus its good to recycle!

The heatsinks were just a fraction too wide to fit inside this clamshell style case, so
I had to shave a whisker off the edge.... anglegrinder with 1mm "Razer-blade" made short
work of it and the heatsinks fit perfectly now.

I drilled a (pilot) hole for the screws that mount the rectifiers.

Mounting the rectifiers to the clamshell was another metalthread into the side of each
heatsink through the case. I'll add the current meter to the front, along with "Brake" and
primary/secondary battery selectors, and connectors on the rear.

Knocked up a front panel from some old, leftover black perspex. Unfortuntely, its ancient
and very fragile (brittle). Broke two corners off while drilling it out :(

Have front-panel switch for (electric/dynamic) brake, 20A meter for wind and 10A meter for
solar, and a front-panel switch to let me send solar to main battery bank, or secondary
for maintenance charging.

Rear panel has 3-way strip for 3-phase from turbine, 6-way for pri, sec battery banks and
PV input from solar array. Still need to build a back panel yet, but for now it works.



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