An Equivalent Magnetic-Circuit-Modeling Approach for Analysis of Conical Permanent Magnet Synchronous Motor.

Area of Science:

• Electrical Engineering
• Marine Engineering
• Electromagnetics

Background:

• Shaftless propulsion offers high efficiency and low noise for marine applications.
• Integrating rim-driven thruster (RDT) motors with vessel hulls requires precise geometric and electromagnetic compatibility.
• Conical motors present unique challenges for electromagnetic analysis due to their geometry.

Purpose of the Study:

• To develop an advanced electromagnetic model for conical permanent magnet synchronous motors (CPMSMs).
• To accurately analyze magnetic fields, considering end effects and magnetic saturation.
• To provide a framework for the rapid electromagnetic analysis and design of CPMSMs for marine propulsion.

Main Methods:

• Development of a 3D equivalent magnetic circuit model (EMCM) for CPMSMs.
• Decomposition of air-gap flux into radial, axial, and tangential components.
• Lumped-parameter network modeling to address end-field nonlinearities and magnetic saturation.
• Adoption of trapezoidal expanded magnet layout and magnet-pole-trimming for sinusoidal flux distribution.

Main Results:

• A novel EMCM accurately characterizes CPMSMs, accounting for complex magnetic phenomena.
• The model facilitates the design of motors with improved electromagnetic performance.
• A 10.5 kW prototype motor was successfully designed using the EMCM and validated via FEA and experiments.

Conclusions:

• The proposed EMCM provides a robust theoretical framework for the rapid electromagnetic analysis of CPMSMs.
• This technology enhances the design and integration of efficient shaftless propulsion systems.
• The findings support the advancement of high-performance marine propulsion technologies.