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Old 03-23-2011, 01:53 AM   #9 (permalink)
Join Date: Mar 2010
Location: New Zealand
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Oh dear, what a long rambling post, just like the ones I do when I've had a glass (or two) of red wine.
Firstly, your pictures didn't appear. Don't ask me, I can barely get mine up there, let alone put them where I want.
Second/Third?fourth - whatever, if your motors are rated at 24 V and 80A, that's only just under 2 kw which is pretty useless. Now, that will be a continuous rating (I'm sure) and you can overdrive them by heaps as long as it isn't for too long. For example, my L91 motors have a continuous rating of about 14 kw each (x2 for 28 kw) but they can do a peak of about 47 kw (94 kw for 2). gliding along the road at about 55 kph takes about 16 kw or so - maybe a bit more - and that's only 8 kw per motor, so they only get a bit warm Acceleration is where the big power demand is, but that's only for a short time, so no prob. Seems like 110 kph needs about 26 kw or 13 kw per motor and that's getting close to their max rating, so driving for an hour at that speed will warm them up and it does, they get up to about 75 deg C.
Now, you have your pissy little 24V motors that can do 2 kw continuous, you can probably overdrive them by a factor of 5 in the short term, for acceleration say, so you can get 10 kw. But you need a continuous power capability of ??? depends on the size, weight, aero drag and such. A motor cycle will need about 6 kw continuous to go 100 kph (Jeez, that's a rough guess!) and a car about 25 to 30 kw, so your bike will need 3 motors and a car will need 15!
These figures all just ball-park estimates, but based on my experience with both bikes and a car.
The mechanical coupling of all those motors will be the biggest nightmare. Two motors in parallel, easy, just a couple of sprockets and a chain - how do you take the drive off? In series , also easy as long as they are double ended motors.
You go figure out the mechanics and the electronics is a piece of cake!
Sometimes I sits and thinks and sometimes I just sits.
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