Design and analysis of stator modular integrated motor propulsor

Integrated motor propulsor (IMP) is an open-type underwater propulsion device, which has no watertight problem and combines the advantages of permanent magnet motor and pod propeller. In this paper, a novel design of IMP named stator modular integrated motor propulsor (SM-IMP) was introduced. The motor part adopts a modular permanent magnet (MPM) motor with additional tooth structure. Both 18-slot/20-pole and 24-slot/20-pole MPM motors were investigated and compared with traditional permanent magnet motor for IMP. The effects of the additional tooth on the back-EMF, air gap flux density and cogging torque of MPM motors were calculated by using the electromagnetic field analysis software. The results show that the SM-IMP proposed in this paper simplifies the machining process and substantially eliminates the cogging torque, which is beneficial to improve the performance of IMP.