Design of End-Iron-Free Voice Coil Motor with Appropriate PM Length Ratio

The linear voice coil motor (VCM) is widely used in many applications. Many research studies have been done to improve its thrust density. This article proposes a novel end-iron-free VCM topology to suppress the end effect on thrust loss. As the end iron yoke is removed, the reverse flux near the end of VCM has been greatly reduced. For a higher thrust density, the arrangement of unequal length be...