... levitation technology, no iron core, no hysteresis and cogging, low starting torque.2.No mechanical friction, above 98% of generation ... earth permanent magnet, multi-polar, small gap, high power density5.Low speed direct drive, No torque ripple6.Compact, high-volume power ratio7 ... .Due to no iron loss, low heat, small upward temperature. 8.Simple structure, easy to ...