Optimization of the Different Pole Arc Combination to Reduce the Cogging Torque in PMDC Motors

In this paper, the method with different pole arc combination was adopted to reduce the cogging torque in PMDC motors. To minimize the cogging torque, a global optimization algorithm (zooming algorithm) and the finite element method (FEM) are combined to find the best pole arc combination. The Fourier coefficient of the square of magnetic flux density is analyzed to determine the feasible region from which the lowest cogging torque was obtained. Then the zooming algorithm and FEM are used to find the best combination. It can be concluded that the cogging torque is notably reduced