Patent ID: 7134180

Claim:
A method of providing slip energy control in a permanent magnet electrical machine comprising a stator and a magnet coupling uncluttered rotor provided with a plurality of elements for coupling flux to a secondary coil, the method comprising: inducing a flux in the magnetic coupling uncluttered rotor across a first air gap located between the stator and the magnetic coupling uncluttered rotor by conducting a current in a primary winding of the stator of the electrical machine and by positioning a permanent magnet rotor with permanent magnets in said first air gap; positioning the secondary coil across a second air gap from the magnetic coupling uncluttered rotor and facing the magnetic coupling uncluttered rotor; and inducing a slip current in the secondary coil by magnetically coupling the flux through the magnetic coupling uncluttered rotor without inducing a current in the magnetic coupling uncluttered rotor.