Low loss permanent magnet motor

A permanent magnet synchronous motor system comprising:

• a permanent magnet motor having a stator and rotor, the rotor of which includes a permanent magnet and the stator of which includes electrically excitable plural windings for generating a varying magnetic field relative to said windings;
• said stator including a coil form of low magnetic loss material for supporting said windings;
• said permanent magnet motor having said stator coil form as a cylindrical, coil bearing non magnetic material structure with said rotor having first and second cylindrical portions receiving said stator therebetween and having a flux path therearound;
• bearings supporting said rotor relative to said stator, said rotor otherwise being free of physical contact with said stator;
• said rotor having plural, even numbered permanent magnets of alternating polarity orientated with poles facing said stator;
• said stator having said plural coils thereon, each facing a corresponding pole of said rotor;
• means for applying excitation varying at a frequency to said plural windings;
• means for continuously sensing signals developed in said windings at said frequency representative of winding back EMF during the powering thereof as a function of both winding resistance and winding inductance in response to the excitation applied thereto;
• means for controlling the phase angle between the applied excitation and sensed back EMF to provide maximum torque;
• and
• means for integrating a representation of the applied excitation to provide said sensed back EMF.