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Old 07-10-2013, 12:25 AM   #41 (permalink)
MPaulHolmes
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Join Date: Feb 2008
Location: Maricopa, AZ (sort of. Actually outside of town)
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Michael's Electric Beetle - '71 Volkswagen Superbeetle 500000
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What I'm doing now for the MPPT algorithm is just scanning the pwm duties from 400 up to around 725. And instead of monitoring current, I'm summing the current 128 times, and then comparing the sum to the previous sum of 128 currents. It gave very solid results. The pwm duty never varied by more than +/- 5 on a scale of 0 to 1600. It found the peak, and stayed there! I was charging at 45 amps today at about 4:30 pm. Next I just might turn this sucker on at noon and see if we can't blow up the batteries. The efficiency was 99%!! What's that all about?! Here were some typical efficiencies:
99.06973283
99.20951228
99.22393609
99.06973283
98.86593514
98.99944755
98.99944755

I'm going to double check those tomorrow but I think they are pretty close to correct.

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