Comparison of Characteristics of Permanent-Magnet Linear Oscillating Actuator According to Laminated Method of Stator Core

The efficiency of a linear oscillating actuator (LOA) can be increased by reducing the mechanical losses caused by the crankshaft mechanism. In addition, this system has lower noise and fewer vibration effects than rotary motors. In this paper, the features of the stator core in an LOA are examined with regard to a new radial lamination method. When typical rotational equipment is used, the stator core is laminated toward the axis to reduce the eddy current losses. In contrast, the LOA should be laminated in a radial direction. Conventional radial lamination has a weakness when compared with axis lamination: the air gap has a low flux density owing to the small stacking factor. To address this problem, this paper suggests a new radial lamination method that laminates the teeth and yoke of the outer stator in a separated formation. Compared with the existing lamination model, the presenting lamination model multiplies the flux density of the air gap by enlarging the stacking factor. The results indicate that the present lamination model has higher back electromotive force and thrust. In addition, the effect of fabrication error is hardly observed when the new lamination method is applied. Thus, the results suggest that the capability of an LOA can be increased by employing the present lamination method.