Design of high-torque-density double-stator permanent magnet brushless motors

This study proposes and implements an optimal design approach for the double-stator permanent magnet brushless motor. The key is to optimise the split ratio, namely the ratio of the inner-stator outside diameter to the outer-stator outside diameter, of this motor in such a way that the maximum torque density can be achieved. Both finite-element analysis and experimental results are given to verify the validity of the proposed design approach.