[chbot] Help I don't know enough about SMPS! (And can you help me design one pls)

[Volker Kuhlmann]

On Mon 26 Dec 2011 18:27:42 NZDT +1300, Jasper Mackenzie wrote:

[Connecting solar panel to battery and load]

I have heard good things about LT (Linear Technology). Their reference
designs (those in the data sheets and appnotes) are reported to work
reliably. They're big in switch mode designs too. Check their range, but
I suspect you are pushing the limits (mainly input voltage) with your
solar panel. They have a good spice simulator too (LTspice), and are the
only company who bothers to mention Linux and say that LTspice works
under wine. (There was an article in a recent Elektor about that too).
The LT semiconductors should all have spice models for their simulator.
I would make extensive use of that in your position.

From memory many of their appnotes also said how to calculate the
component values, which should be useful if you need to beef it up. I
would expect your biggest problem to be with the inductors (which you
may have to wind yourself) and replacing the transistors with bigger
ones while taking care of some of the parameters that scale
disproportionally with your increased current. Keep in mind that
converters are more efficient if you are able to restrict yourself to
either up or down, but not both.

Look at LED lighting supplies, which may be not too far from what you're
looking for and there's a glut of them everywhere.

For your wind turbine you should probably just get the kit that comes
from the turbine manufacturer. They know what they're doing there. If
you really want to roll your own, my advice is get the solar panel
working first and collect experience there, then scale up.

The obligatory microcontroller is there to log your system state, energy
flow, and control the batteries. If you want to power mains appliances
you need a suitable inverter too. I'd start without that.

HTH,

Volker

-- 
Volker Kuhlmann
http://volker.dnsalias.net/	Please do not CC list postings to me.