Single-Phase Dual-Pole Line Start Permanent Magnet Synchronous Motor

Household applications such as refrigerator compressors, washing machines, evaporative air conditioners, etc. are often run by Induction Motors (IMs) at two operating speeds. The transition between the high-speed and low-speed is typically realized either with a variable frequency drive solution or a structural pole-changing solution. Although the latter solution (i.e., pole-changing) eliminates the cost and losses associated with the drive unit, it requires a larger slot area to accommodate two sets of stator windings. As a result, the efficiency of dual-pole IMs available in the market is less than their single-pole counterpart. Since the efficiency of permanent magnet synchronous motors is generally higher than that of IMs, and to improve the operational efficiency in household applications this paper aims to convert the two-speed single-phase IM with the two-speed single-phase Line Start Permanent Magnet (LSPM) synchronous motor. For this purpose, the first generation of dual-pole (4p/6p), single phase LSPM motor is designed and presented. The performance characteristic of the proposed design is analyzed in finite element (FE) simulation and validated via a series of experimental tests on the motor prototype. © 2025 The Authors.