Design of a 10p-12s SMPM synchronous machine for a dynamic focus adjustment of a laser beam

This paper represents the design concepts and the test results of a Permanent Magnet Synchronous Motor (PMSM) for an electro-mechanical actuator used in a laser-cutting applications, for the dynamic focus adjustment. The motor is directly integrated with the mechanical components in a rotating-ballscrew architecture in order to minimize the total inertia and the actuator´s size. The dynamic motion trajectory imposes a high acceleration-torque at high speeds. A prototype has been manufactured using the design data of the optimization procedure. Due to mechanical considerations and the stringent dimensional limits, the proposed motor has the PMs directly glued on the surface of the steel nut that represents the “rotor”. Test results confirm the performance of the system and the goodness of the prototype.