The invention is a drive system comprising an inverter comprising N arms, each arm including an upper half-arm and a lower half-arm each comprising at least one switching module, a rotary machine connected to the inverter, including a rotor having at least one magnetic element made from a modular magnetization material and a control device which, during magnetization controls the inverter to simultaneously for each one of m arms, set each switching module of the upper half-arm and turned on and each switching module of the lower half-arm is turned off, for each one of k other arms, set each switching module of the upper half-arm to be off and each switching module of the lower half arm to be on, and for each of the remaining arms, set each switching module to be off.

The invention relates to a drive system comprising an inverter a first input, a second input and N outputs, a rotary machine comprising a stator and a rotor comprising at least one magnetic element made from a modular magnetization material, an output switching device connected between a common point and the second input, and a control device which simultaneously during magnetization of the at least one magnetic element step controls the output switching device to be on for a predetermined magnetization time interval, and controls the inverter to connect during the magnetization time interval, the first input to at least one and at most N-1 outputs.

A permanent magnet synchronous motor includes a stator, a rotor rotatable relative to the stator, and a magnetic structure with a low coercive force magnet and a high coercive force magnet that are arranged magnetically in series with respect to each other to define a pole-pair of the permanent magnet synchronous motor. A magnetization level of the low coercive force magnet is changeable by a stator current pulse such that a stator magnetomotive force at a rated current is equal to or larger than a product of a magnetic field strength for fully magnetizing the low coercive force magnet and a thickness of the low coercive force magnet.

A permanent magnet synchronous motor includes a stator, a rotor rotatable relative to the stator, and a magnetic structure with a low coercive force magnet and a high coercive force magnet that are arranged magnetically in series with respect to each other to define a pole-pair of the permanent magnet synchronous motor. A magnetization level of the low coercive force magnet is changeable by a stator current pulse such that a stator magnetomotive force at a rated current is equal to or larger than a product of a magnetic field strength for fully magnetizing the low coercive force magnet and a thickness of the low coercive force magnet.

A permanent magnet synchronous motor includes a stator, a rotor rotatable relative to the stator, and a magnetic structure with a low coercive force magnet and a high coercive force magnet that are arranged magnetically in series with respect to each other to define a pole-pair of the permanent magnet synchronous motor. A magnetization level of the low coercive force magnet is changeable by a stator current pulse such that a stator magnetomotive force at a rated current is equal to or larger than a product of a magnetic field strength for fully magnetizing the low coercive force magnet and a thickness of the low coercive force magnet.