Cogging Torque Reduction in PM machines Used in Electro-Mechanical Battery

Abstract

Electro-Mechanical Batteries have important

advantages comparing chemical batteries and using them is

popularized specially in Low Earth Orbit satellites recently.

External rotor Permanent Magnet machines are used in these

systems as Motor/Generator. The main problem of these

machines is their cogging torque originated from high strength

PM's. Different methods for cogging torque reduction are

available, anyway not all of them are applicable in spacecraft

EMB’s machines. In this paper different method of cogging

torque will be investigated and proper manners will be

extracting. Finite Element Method (FEM) simulations are used

for this aim.