Sorry, meant to add a link to some photos of the ME0913 motor disassembled to that last post. They aren't the ones I was thinking of, but nevertheless they show that it's just an ordinary axial BLDC arrangement internally: http://www.diyelectriccar.com/forums/showthread.php/ripperton-electric-track-bike-41173p20.html?highlight=ME0913
Also I missed your reference to speed/torque control strategies. I've used battery current control and motor voltage control strategies on my simple BLDC controllers and they both work OK. I'm about to try phase current control to get true torque control (battery current control gives power, rather than torque control, because of the current multiplication effect of the controller). All these control strategies work OK with a plain old ordinary trapezoidal controller and BLDC motor, provided you put the current sensor(s) in the right place and have a fast enough control loop to run the PID throttle control element for current or power control (no PID loop needed for speed control).
There's no need to go to sinusoidal control to get these throttle profiles, plus, depending on the exact topology of the motor you may not want sinusoidal control anyway. The ME0913 is a good example, as the BEMF waveform (derived from spinning the motor mechanically with the windings loaded) is closer to trapezoidal than sinusoidal, indicating that there's little to be gained (other than making the motor run a little quieter) by using the more expensive controller type.
Jeremy
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