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Old 05-29-2012, 01:31 PM   #19 (permalink)
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Originally Posted by fb_bf View Post
Thanks for the lengthy reply. I'll look into what you said about the controller. I have been assuming an 85% to 90 % efficiency for the motor, 10% loss in the drive train, and a couple of percent for the controller.
What you suppose may be true on brand new AC drive, DC drive, especially older setups weren't too swift at lower rpms, the controller itself may not dissapate much but more power is lost in the motor as well in these situations, which means if RPM & throttle are too low composite efficiency can drop into the 75% area.

Normally most folks who have EVs never have so much voltage to end up in this region but you setup may be light enough and aero enough to get awefull close.

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