There are presented various embodiments disclosed in this application, including methods and systems of arranging permanent magnets to switch from a first configuration designed for a first torque output to a second configuration designed for a second torque output.

A magnetically reconfigurable robot joint motor includes a coil stator, a permanent magnet rotor and a magnetic reconfiguration unit. The magnetic reconfiguration unit is arranged around an outer periphery of the permanent magnet rotor, and a coil connected to a control circuit is wound on an outer layer of the magnetic reconfiguration unit. When it is necessary to execute low rotation speed or zero rotation speed operating conditions, the control circuit inputs current pulses of different strengths, so that the magnetic reconfiguration unit obtains permanent magnetization of corresponding degree, and generates a magnetic field which acts together with a magnetic field of the permanent magnet rotor, so as to maintain a torque required for output.

The permanent magnet machine includes a stator, a rotor inside the stator and a ferromagnetic component fixed axially movably to the rotor. The ferromagnetic component is configured for actuating axially toward the rotor to weaken a magnetic field of the rotor. The method of constructing a permanent magnet machine includes providing a stator and a rotor inside the stator; and axially movably fixing a ferromagnetic component to the rotor such that the ferromagnetic component is configured for actuating axially toward the rotor to weaken a magnetic field of the rotor.

An electrical system includes a power inverter connected to a battery and outputting a polyphase voltage, and a cycloidal reluctance machine. A machine rotor provides output torque, and is surrounded and separated from the stator by an airgap. The rotor includes permanent magnets providing a fixed-orientation rotor field. The stator includes windings proximate the permanent magnets and electrically connected to the inverter to form stator electromagnets. The rotor field augments the stator field to boost output torque. The rotor is eccentrically positioned with respect to the stator to move with two degrees of freedom (2DOF), including rotating motion and orbiting motion about a center axis of the stator. A rotor constraint mechanism constrains motion of the rotor, such that the rotor is able to generate and transmit the output torque to a coupled load in at least one of the 2DOF.

An electrical system includes a power inverter connected to a battery and outputting a polyphase voltage, and a cycloidal reluctance machine. A machine rotor provides output torque, and is surrounded and separated from the stator by an airgap. The rotor includes permanent magnets providing a fixed-orientation rotor field. The stator includes windings proximate the permanent magnets and electrically connected to the inverter to form stator electromagnets. The rotor field augments the stator field to boost output torque. The rotor is eccentrically positioned with respect to the stator to move with two degrees of freedom (2 DOF), including rotating motion and orbiting motion about a center axis of the stator. A rotor constraint mechanism constrains motion of the rotor, such that the rotor is able to generate and transmit the output torque to a coupled load in at least one of the 2 DOF.

An electrical machine has a stator with windings, first and second rotors, and an electrical output regulator. The first rotor carries alternating polarity first field magnets, such that, on drive mechanism rotation, the windings interact with the magnetic flux produced by the first magnets to create an EMF. The second rotor carries alternating polarity second field magnets, and has first and second rotational positions to reduce and increase, respectively, the magnetic flux energy. The electrical output regulator regulates a current from the windings to produce a torque on the rotors, as the drive mechanism increases from zero rotational speed, the torque rises above a threshold level that moves the second rotor from the first to the second rotational position, and, as the drive mechanism further increases the rotational speed, the torque peaks and then drops below the threshold level to move the second rotor back to the first rotational position.

The electrical motor includes a stator and a rotor configured to be rotated about an axis wherein the rotor includes at least three rotor subsegments, wherein a first and second rotor subsegment can be turned relative to one another about the axis in response to a rotation speed range being above a predetermined threshold value of a rotation speed of the electrical machine.

An electrical submersible pump motor has rotor sections mounted along a length of a shaft to cause rotation of the shaft. Pole magnets are spaced apart from each other and mounted to the shaft. Each of the pole magnets is polarized with a north pole on one of its inner and outer sides and a south pole on the other of its inner and outer sides. An orthogonal magnet is mounted between each of the pole magnets. Each of the orthogonal magnets is polarized with a north pole on one of the its ends and a south pole on the other of its ends.

A rotary electrical machine including an annular stator having a stator core around which an armature winding is wound, and a rotor arranged on an inner circumference of the stator, a permeance of a q-axis magnetic circuit is made larger than a permeance of a d-axis magnetic circuit. The machine includes a switch for supplying power to a field winding and controller. The controller calculates the duty ratio on the condition that an upper limit of the duty ratio of the switch is a predetermined value and turns on/off the switch based on the calculated ratio. The predetermined value is set to a value larger than the duty ratio corresponding to the field current that gives the maximum reduction amount of the inductance of the field winding with respect to an increasing amount of the field current in a range that the current can take and is less than 100%.

A rotary electrical machine includes a switch for supplying power to a field winding and controller. A ratio of an on-time to one switching cycle of the switch is defined as a duty ratio, and a duty ratio which is larger than the duty ratio corresponding to the field current that gives the maximum reduction amount of the inductance of the field winding with respect to an increasing amount of the field current in a range that the current can take and has a value less than 100% is set as a predetermined value. The controller calculates the duty ratio wherein an upper limit of the ratio is the predetermined value and turns on/off the switch based on the calculated duty ratio. Also, a relay and abnormality detection part that detects abnormality in the switch. The relay is switched to off in response to the occurrence of abnormality being detected.