Abstract：The paper proposes a novel permanent magnet synchronous motor with controllable flux. The unique rotor structure makes the performance of magnets could be changed by d-axis current pulse. At the same time, q-axis magnetic motive force, produced by load current, could not influence the statement of magnets. To the analysis of magnetization process of permanent magnets, the paper builds a magnetization model including initial magnetization and repeated magnetization in which magnetization ratio curve is expended. Then combine magnetization model and local magnetic hysteresis loops into determining the state of magnet. On the basis of the model, the paper computes magnetization magnetic field and EMF by finite element method. Prototype test results are consistent with those by finite element method, showing the effectiveness in flux weakening and applicability of the magnetization models.
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2009, Vol. 24 
