The motor does not run on a 2-wire PWM DC current, it is brushless. Switching of the 3 wiring phases is handled by the controller, not the motor. The hall sensors in the motor provide a position signal to the controller.
You might be able to duplicate the functionality with a custom built controller. Starting points for your custom design might include the OSMC project and a Light Electric Vehicle controller being built by FrankG (here:
http://www.theworkshop.ca/energy/picox/4/picox4.htm). I believe both designs are for brushed motors, so you will need to make the jump to 3-phase brushless motors. A gentleman on the Endless Sphere forums has posted pictures of his own custom designed controller, which I believe is a brushless motor controller, but he has not posted schematics or source code. I don't think he ever will.
You may want to get this information confirmed, but I believe the motor is wired in wye configuration, and the hall sensors are spaced at 120 degrees of phase. Hopefully the info helps for your custom design.