A design of slotless BLDC motor for robot using equivalent magnetic circuit model

An analytical model for slotless brushless DC motors having four poles and twelve single coils is presented. To determine a back EMF constant of motor with hexagonal windings, winding forming factor taking into account winding shapes is introduced. The calculated results are verified with FE analysis and manufacturing through an example model, and electromagnetic parameters, such as EMF, motor constant with respect to the winding angles are analyzed.