Hi,
Find out how they do it in the other engines.
Have you got a scope to look at the waveform you are using to power the stator?
What waveform are you trying to send to the stator, sinewave, modified sine or square wave?
Have you calculated from your code the maximum speed it is possible to output your signals.
Can you please post some pictures of your project?
Can you please post a full schematic of your project including the stator windings?
Thanks.. Tom... 
