Systematic Design Approach for Dual-Pole Line Start Permanent Magnet Synchronous Motors

Dual-pole Permanent Magnet (PM) synchronous motor is an emerging technology that can operate at two different synchronous speeds at a fixed frequency. The two-speed operation is realized solely based on the pole-changing concept without the need for a drive circuit and/or a reduction gear. Therefore, these machines are becoming potential contenders to Induction Motors (IM) in two-speed applications, such as fans, pumps, compressors, etc. contingent upon that issues related to their relatively poor startup and higher production cost are addressed. This paper aims to facilitate the design process of the family of dual-pole PM synchronous machines by proposing a new design algorithm for any two arbitrary pole numbers. By leveraging the proposed design algorithm, a new (4p/8p) structure is proposed featuring dual magnetic pole numbers in a single rotor layout.