A new flux weakening method of permanent magnet synchronous machine

As traditional permanent magnet synchronous machines (PMSM) are deficient in flux weakening operation, a new method of automatic flux weakening with the rotor speed is presented. The flux weakening principle of permanent magnet synchronous motor (PMSM) is introduced. The flux weakening speed range is investigated and the forces on magnetic conductor which for adjusting the leakage reluctance of the rotor are analyzed in detail. Results from the finite element field emulation analysis are presented to verify the validity and feasibility.