Analytical Calculation of Magnetic Field in Surface-Inset Permanent Magnet Motors

This paper presents an analytical approach to calculate the magnetic field distribution in surface-inset permanent magnet motors. A series-slot analytical model is newly proposed to describe the magnetic field behavior by a set of partial differential equations in terms of scalar magnetic potentials. The field solutions are determined by considering the boundary constraints. Then, the cogging torque characteristic is deduced by calculating the Maxwell tensors. The accuracy of the proposed analytical calculation is verified by comparing the field distribution and cogging torque results with those obtained from the finite element method.