ANTI-COGGING APPARATUS FOR PERMANENT MAGNET ELECTRICAL MACHINES

摘要

The present invention provides cancellation of the cogging torque of a permanent magnet electrical machine using two sets of magnetic elements, one set being mechanically coupled to the stator and the other set being mechanically coupled to the rotor of the machine. At least one of the two set comprises permanent magnets and the magnetic elements of the other set can be made of permanent magnets or non-magnetized ferromagnetic materials such as soft iron. When the arrangement of the elements of the two sets are properly designed, magnetic attraction and repulsion forces between the magnetic elements of the two sets as the machine operates produces an anti-cogging torque that substantially cancels out the cogging torque of the machine.