A miniature transformer-coupled high-speed synchronous motor

A synchronous motor having a bar stator winding fed from an integral phase-splitting transformer is described. The rotor magnet system is constructed from sintered samarium cobalt and reinforced with nonmagnetic stainless steel. The 1 cm-diameter rotor is capable of speeds up to 150 000 rev/min with an output of approximately 100 W. Electrical and mechanical aspects of the design are discussed and test results at supply frequencies up to 2.5 kHz are given