Hl Mando Corporation

North Carolina State University

Mando Corporation

Md Sariful Islam

Mohammad S Islam

Iqbal Husain

Mazharul Chowdhury

Tomy Sebastian

Christian Ross

Christopher William Lutz

Gregory Dale Buckner

Abraham Tesfamicael

Ritvik Chattopadhyay

Adeeb Ahmed

Md Ashfanoor Kabir

Amina Shrestha

Scott Blehm

Various examples related to stator and rotor configurations for the improvement in torque density and/or efficiency in AC machines are presented. In one example, a bar wound stator includes a stator core with winding slots; a first group of bar type conductors in the winding slots adjacent to a proximal end adjacent to a rotor air gap surface of the stator core; and a second group of bar type conductors in the winding slots adjacent to a distal end adjacent to a back-iron section of the stator core. The first group of bar type conductors having a first cross-sectional area and the second group of bar type conductors having a second cross-sectional area greater than the first cross-sectional area. In another example, a motor includes the bar wound stator and a rotor such as, e.g., a permanent magnet rotor. The motor can be utilized in hybrid or battery electric vehicles.

Torque density and efficiency improvement in AC machines

A motor comprises: a stator assembly; and a rotor assembly configured to be rotatable relative to the stator assembly, wherein the stator assembly comprises a stator core having stator slots; and electrical conductors at least partially disposed in the stator slots, the electrical conductors having hairpin winding segments, each of the hairpin winding segments comprising: first and second legs, each of the first and second legs having an in-slot portion disposed in one of the stator slots, and an endturn portion formed between the first and second legs. The endturn portion formed between the first and second legs is thicker than the in-slot portion of the first and second legs, disposed in the stator slot. Further, thicknesses of open end portions formed at ends of the first and second legs are different from a thickness of the in-slot portion of the first and second legs, disposed in the stator slot.

Electric motor having hairpin type windings and method for designing the same

A vehicle wheel assembly comprises: a wheel for mounting a tire thereon; and an in-wheel motor mounted in the inner space of the wheel and comprising: a rotor connected to the wheel, wherein a magnet is mounted to a center portion of the rotor rotatably coupled with a bearing assembly and arranged at a rotation axis of the wheel, a stator configured to drive the rotor, a rotary sensor disposed in sensing relationship with the magnet mounted to the center portion of the rotor, the rotary sensor configured to be responsive to rotation of the magnet for generating a signal, and an electronic device comprising a circuit board and electronics; and a brake actuator configured to apply brake to the wheel or the rotor. The electronics mounted on the circuit board comprise a single electronic control unit configured to control both the in-wheel motor and the brake actuator.

In-wheel motor with motor position sensor and brake system

Various examples are provided related to 3D airgap electric machines and winding embedded liquid cooling. In one example, an electric machine includes a stator assembly with stator windings supported by a stator core and an outer rotor assembly includes a radial plate surrounding the stator assembly and an endplate at a first end of the radial plate adjacent to the first end of the stator core. The stator windings can include a first portion extending along an axial length of the stator core and a second portion at a first end of the stator core that extends radially inward towards a shaft of the electric machine. The radial plate can include magnets distributed about the radial plate. In another example, a stator assembly includes stator windings supported by a stator core with a winding support including cooling channels distributed between the stator windings. The winding support can be nonmagnetic.

Three-dimensional airgap electric machines employing winding embedded liquid cooling

A rotor assembly of a motor is configured to be rotatable relative to a stator. The rotor assembly may comprise a permanent magnet rotor segment comprising permanent magnets, the permanent magnet rotor segment configured to be rotatable by a magnetic field generated by the permanent magnets; and a reluctance rotor segment comprising flux barriers, the reluctance rotor segment configured to be rotatable by magnetic reluctance formed by the flux barriers. The permanent magnet rotor segment and the reluctance rotor segment are axially stacked relative to each other so that at least a part of a first torque ripple generated by the permanent magnet rotor segment and at least a part of a second torque ripple generated by the reluctance rotor segment can cancel each other. The permanent magnet rotor segment may be a rare earth permanent magnet rotor, and the reluctance rotor segment may be a synchronous reluctance rotor.

Electric motor having stacked different rotor segments and method for designing the same

Various examples are provided related to machines utilizing heavy rare earth (HRE) free permanent magnets. In one example, a rotor assembly including a rotor core having a plurality of rotor slots and magnets positioned within the plurality of rotor slots. At least a portion of the magnets are free of heavy rare earth (HRE) elements. The magnets can include a combination HRE segments and HRE-free segments or can be free of HRE elements. The rotor assembly can be included in an electric machine such as, e.g., a permanent magnet (PM) machine.

Machines utilizing heavy rare earth free permanent magnets

A permanent magnet motor comprises: a rotor assembly configured to be rotatable relative to a stator, wherein the rotor assembly defines magnet pockets, a segmented permanent magnet comprising a plurality of magnet segments, which include one or more magnet segments of the segmented permanent magnet have different magnetic material from another or other magnet segments of the segmented permanent magnet, is disposed in each of the magnet pockets of the rotor assembly. The segmented permanent magnet is segmented in a circumferential direction. The one or more magnet segments of the segmented permanent magnet comprises magnetic material having higher coercivity, or operable at a higher temperature, than the another or other magnet segments of the segmented permanent magnet. The one or more magnet segments of the segmented permanent magnet comprise rare earth permanent magnet, high energy density magnet, samarium cobalt (Sm&#x2014;Co) magnet or neodymium iron boron (Nd&#x2014;Fe&#x2014;B) magnet.

Electric motor having rotor assembly with segmented permanent magnet

A permanent magnet motor comprises: a stator comprising teeth; and a rotor rotatable relative to the stator, the rotor having a plurality of poles, wherein each pole of the rotor comprises a pair of magnet retention slots, each magnet retention slot accommodating a magnet. Surfaces of the teeth of the stator facing the rotor are flat or have an arc shape. Each magnet retention slot may have a plurality of angled slot surfaces forming a first barrier around a corner of the magnet positioned closest to an outer surface of the rotor. At least three second barriers are positioned around a mid-axis extending along between the pair of the magnet retention slots. Each magnet retention slot comprises a slot surface slanted or curved relative to a second side surface of the magnet facing an inner surface of the rotor to form a third barrier around an end of the second side surface of the magnet.

Electric motor having permanent magnet rotor and stator

An electric motor with a rotor and a stator, where the rotor and/or the stator can comprise two or more sections, and a torque ripple caused by the magnetic field(s) associated with a section of the rotor (or stator) can at least partially counters torque ripple caused by the magnetic field(s) associated with other section(s) of the rotor (or stator).

Variable motor laminations

A vehicle wheel assembly comprises a wheel for mounting a tire thereon and having an inner space; and an in-wheel motor mounted in the inner space of the wheel and comprising: a rotor connected to the wheel and configured to rotatable relative to a stator, the stator configured to drive the rotor, an electronic device comprising a circuit board and electronics mounted on the circuit board and configured to control the in-wheel motor, two-phase dielectric material, and covers coupled with the stator to form a hermetic enclosure. The electronic device and the two-phase dielectric material are contained in the hermetic enclosure formed by the wall of the stator and the covers coupled with stator, and the two-phase dielectric material is in contact with the wall of the stator and the electronic device to cool the stator and the electronic device by transitioning between a liquid phase and a gaseous phase, conduction, and convection.

In-wheel motor with cooling system

Various examples related to shifted fractional pitch wye-delta multilayer windings and their use in AC machines. In one example, a winding includes a first wye-delta winding with first wye and delta windings for each phase and a second wye-delta winding with second wye and delta windings for each phase. The first and second wye windings for each phase are connected in series and the first and second delta windings are connected in series, and formed wye and delta windings are connected in a wye-delta configuration thereby providing an electrical phase shift between the two windings. The windings are interdigitated to provide a physical shift between the first and second wye windings and the first and second delta windings. Such windings can be used in, e.g., permanent magnet synchronous machines, synchronous machines, reluctance machines, and induction machines.

Growing community of inventors

Raleigh, NC, United States of America

Md Sariful Islam