We all know solar panels are expen$ive, and therefore we need to extract every possible joulle (or is that jewel?) of energy we can. Whilst an MX60 is a fine piece of engineering, I have read comments on here by at least several people who have managed to destroy them. Replacement cost for those of us downunder (Australia) being in the order of AU$1000 each, I figure there's got to be an alternative for those of us proficient at things electronic.
Working forwards from this article http://www.acs.comcen.com.au/buildppt.html where he shows that it is only necessary to maintain the cell voltage at 17 volts (thereabouts) for a 12 volt panel, and marrying this idea to an ex-telecoms 48-24 volt 1KW inverter which I picked up from my friends at oatley electronics
for $44.00, I plan to put an op-amp between the cell voltage and the output voltage adjustment pot on this power supply. This will effectively adjust the ouput current to maintain a constant input voltage. This page http://www.oatleyelectronics.com/powersup.html and find SMPS1 will give more details.
Now, if the mppt point for a typical 12 volt panel is about 17 volts, then 3 panels in series will give me 51 volts, well within the input voltage specs for this inverter. Ultimately, I'd like to have 3 banks each with 3 x 80 watt panels. 720 watts, which should approach the max efficiency point of the inverter, if it follows the typical inverter.
I had originally planned to implement this with the MPPT controller I talked about previously http://www.fieldlines.com/story/2006/3/12/14840/1315 but I'm thinking this simplified appraoch is closer to the KISS ideal.
More details later after I finish the (almost finished) dump load controller.
Amanda