An electric propulsion system for an aircraft includes a nacelle and an electric machine. The electric machine includes a stator positioned in the nacelle, and a rotor and fan assembly positioned in a primary flow path through the nacelle. The rotor and fan assembly includes a cylindrical fan shroud, a plurality of rotor magnets positioned on an outer surface of the fan shroud, and a fan hub mounted on a central support shaft via one or more bearings. A plurality of fan blades extend between an inner surface of the fan shroud and an outer surface of the fan hub. The rotor magnets may be loaded in compression in a radial direction when the rotor and fan assembly is at rest. The fan blades may be pre-stressed in a radial direction when the rotor and fan assembly is at rest.

A stator of an external rotor motor supports a plurality of excitation windings. At least one heat dissipation means is provided, for discharging heat in an axial direction. The heat dissipation means contacts the end face of at least one excitation winding or a potting compound or insulation enclosing the excitation winding and is also connected to a heat sink, in the form of the stator carrier, a cooling element and/or a housing, for removing the heat.

A stator of an external rotor motor supports a plurality of excitation windings. At least one heat dissipation means is provided, for discharging heat in an axial direction. The heat dissipation means contacts the end face of at least one excitation winding or a potting compound or insulation enclosing the excitation winding and is also connected to a heat sink, in the form of the stator carrier, a cooling element and/or a housing, for removing the heat.

The invention relates to an in-wheel motor (100) comprising a rotor (110A, 110B) coaxially surrounding a stator (102), the stator comprising electromagnets (104), the electromagnets in working producing heat, the heat at least in part removed from the stator by gas, characterized in that the motor comprises an electric fan (150) internal to the rotor for displacing the gas.

The invention relates to a thermodynamic system (10), notably a system (10) implementing a thermodynamic Rankine cycle, comprising a circulation loop (31-36) for the circulation of a working fluid, said loop (31-36) comprising an energy production means (20), said system (10) also comprising a device for cooling said energy production means (20) and a channel (37, 38) designed to supply said cooling device with working fluid from said loop (31-36) and to return said working fluid into said loop (31-36), said cooling device being designed so as to cool said energy production means (20) by vaporisation of the working fluid inside said production means (20), said working fluid entering said energy production means (20) in the liquid phase.

The invention relates to a thermodynamic system (10), notably a system (10) implementing a thermodynamic Rankine cycle, comprising a circulation loop (31-36) for the circulation of a working fluid, said loop (31-36) comprising an energy production means (20), said system (10) also comprising a device for cooling said energy production means (20) and a channel (37, 38) designed to supply said cooling device with working fluid from said loop (31-36) and to return said working fluid into said loop (31-36), said cooling device being designed so as to cool said energy production means (20) by vaporisation of the working fluid inside said production means (20), said working fluid entering said energy production means (20) in the liquid phase.

Disclosed are liquid coolants for electric systems and methods of making the same. An example liquid coolant for electric systems may comprise: a base oil, wherein the base oil is a major component of the liquid coolant; and a dissolved gas in an amount sufficient to have a measurable effect on fluid viscosity of the liquid coolant; wherein the liquid coolant has a kinematic viscosity at 100° C. of about 7 cSt or less.

Disclosed is a hermetic AC electric motor that includes harmonics shunting such that high frequency harmonics are shunted from the AC electric motor without the use of one or more high frequency filters in the associated motor drive. A related method of operating an AC electric motor includes shunting high frequency harmonics to a fluid passing through the AC electric motor. Also disclosed is a simplified variable speed motor drive system which eliminates the need for a filter for removing high frequency harmonics.

Disclosed is a hermetic AC electric motor that includes harmonics shunting such that high frequency harmonics are shunted from the AC electric motor without the use of one or more high frequency filters in the associated motor drive. A related method of operating an AC electric motor includes shunting high frequency harmonics to a fluid passing through the AC electric motor. Also disclosed is a simplified variable speed motor drive system which eliminates the need for a filter for removing high frequency harmonics.

A powered system that has an electric power system with a stator having plural poles with each pole having a conductive winding that may surround the corresponding pole and may be configured to generate a magnetic field, and a rotor that may be configured to rotate in response to the magnetic field generated by the stator. The at least one of the conductive windings may be insulated with an insulation material configured to conduct heat from the at least one conductive winding while operating at a temperature above 600° C.