Computer aided analysis of a DC brushless motor by means of a finite element technique

The analysis of permanent magnet DC brushless motors can be conveniently performed by means of the finite element method, which gives the magnetic field distribution in complicate geometries taking into account the properties of saturable materials. Some facilities of the proposed computer aided analysis package are presented. The motor is analyzed both at rated and no-load operating conditions evaluating torque-angle curves, induction waveforms in the teeth region, and induced emf diagrams. The overload conditions are investigated to estimate the localized magnetic saturation and the demagnetizing effects on permanent magnets. The computed results are found to be in satisfactory agreement with the experimental ones