BLDC vs AC Squirrel Cage Induction Motors: Torque, Efficiency, and EV Applications

I've done some searching and there is plenty of comparison between similar motor tech, (such as slip-ring AC vs squrrel cage AC) but I haven't found anything compaing brushless DC motors to AC "squirrel cage" induction motors.

The reason I am asking is that AC motors are often used in electric vehicles due to starting torque, high speed, and regenerative breaking, but it seems BLDC has those same characteristics -- yet easier to control.  Therefore, could somebody break down torque/efficiency of both kinds for me?

Thanks,
-KC

hi,

here is a "good comparison("")":http://www.orientalmotor.com/brushless-dc-motors/technology/AC-brushless-brushed-motors.html on ac motor and bldc. Read about why most operators choose "bldc motors("")":http://www.pfonline.com/articles/ac-versus-bldc-motors.

All motors internally need an alternating field and therefore an alternating current to create motion - so a motor that works with DC uses a commutator and brushes to achieve this. A BLDC motor achieves the same thing electronically. An AC motor does not need to do this (i.e., have commutation and brushes, etc) so in that sense a BLDC motor superficially is similar to an AC motor.