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Old 11-24-2010, 06:36 PM   #4051 (permalink)
Join Date: Mar 2010
Location: New Zealand
Posts: 181
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Been a while, but I finished my controller and it works pretty well. I used pcbs from Paul and bought the bits from Ian Bartie in Australia. He supplies a copper heat spreader bar! My case is folded from 3mm Al with a big lump of finned heatsink bolted to it - eight bolts in two rows of four. One row is the bolts through the heat spreader bar and the other row is four bolts from inside tapped into the heat sink base.
It powers two Advanced L91 motors connected in series and driven by 45 x Li cells also in series giving 144v. Pushes a 1988 BMW 318 (E30) along the road with direct drive ie no clutch or gearbox.
Top speed is just 100 kph and acceleration from 0 to 80 kph is about 12 seconds. I did have the motors connected in parallel at one stage and that gave a top speed of about 130 kph but the acceleration was very snail like. So, not enough torque (current) for good acceleration with parallel connection and not enough volts for good top speed with serial connection. Have to figure out a switch!
It draws 170A from the battery at full speed.
RTD Explorer tells me the heat spreader temp sits around 43 - 45 deg C during continuous operation at about 50 - 70 kph (depends on the speed zones). Outside temp was 22 deg C.
Done just on 1000 kms with it now and I get about 120 kms before the volts drop below 135.
I'd put a picture here if I knew how!

Last edited by harlequin2; 11-24-2010 at 07:04 PM..
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