An electric motor for a vapor compression system is disclosed. The electric motor is provided with a working fluid. The electric motor includes a housing forming cavity therein. The housing includes a rotor, a stator, and a shaft. The rotor is secured to the shaft and the stator surrounds at least a portion of the rotor. An airgap is formed between the rotor and the stator. An inlet of the housing receives the working fluid and is in fluid communication with the airgap. An outlet of the housing is in fluid communication with the airgap and receives the working fluid from the airgap. The electric motor further includes an impeller that induces flow of the working fluid between the inlet and the outlet.

A magnetic pole piece device disposed between an inner diameter side magnet field and an outer diameter side magnet field of a magnetic gear, includes: an outer circumferential cover member disposed opposite to the outer diameter side magnet field and having a cylindrical shape; an inner circumferential cover member disposed opposite to the inner diameter side magnet field and having a cylindrical shape; and a plurality of magnetic pole pieces disposed at intervals in a circumferential direction between the outer circumferential cover member and the inner circumferential cover member. The outer circumferential cover member includes a plurality of outer circumferential side facing portions facing outer circumferential surfaces of the plurality of magnetic pole pieces, and a plurality of outer circumferential side connecting portions for connecting two adjacent outer circumferential side facing portions of the plurality of outer circumferential side facing portions.

A system includes an electric generator, a power electronics system, and a heat exchanger. The electric generator includes a turbine wheel, a rotor, and a stator. The turbine wheel is configured to receive process gas and rotate in response to expansion of the process gas flowing into an inlet of the turbine wheel and out of an outlet of the turbine wheel. The rotor is configured to rotate with the turbine wheel. The electric generator is configured to generate electrical power upon rotation of the rotor within the stator. The power electronics system is configured to convert the electrical power to specified power characteristics. The heat exchanger includes a first side in fluid communication with the process gas and a second side in fluid communication with a fluid stream from a second system. The heat exchanger is configured to cool the fluid stream using the process gas.

Provided is an electric drive device which controls a current supplied to coils during normal operation so as to be less than a current limit value when normal, which is determined from heat generating properties and heat radiating properties of a thermally coupled body that includes the coils and an inverter circuit. When an abnormality in each group or each phase of the coils and the inverter circuit is detected, the supply of current to all phases of a group suffering an abnormality in the coils, or to a phase that is not capable of continuous operation, is stopped or reduced; and the limit value of the current supplied to a coil that is capable of continuous operation is reset to a current limit value in the event of abnormality, which is larger than the current limit value when normal, within the range of improvement of the heat generating properties of the thermally coupled body due to the stopping or reduction of the supply of current.

Provided is an electric drive device which controls a current supplied to coils during normal operation so as to be less than a current limit value when normal, which is determined from heat generating properties and heat radiating properties of a thermally coupled body that includes the coils and an inverter circuit. When an abnormality in each group or each phase of the coils and the inverter circuit is detected, the supply of current to all phases of a group suffering an abnormality in the coils, or to a phase that is not capable of continuous operation, is stopped or reduced; and the limit value of the current supplied to a coil that is capable of continuous operation is reset to a current limit value in the event of abnormality, which is larger than the current limit value when normal, within the range of improvement of the heat generating properties of the thermally coupled body due to the stopping or reduction of the supply of current.

A power tool is provided that, in one version, includes a front housing that supports an output drive, and a back cap located opposite the front housing. The back cap receives at least one fastener of the plurality of fasteners. A motor housing supports a motor and is located between the front housing and the back cap. The motor includes a rotor that is configured to rotate about a motor axis to drive rotation of the output drive. The fastener is disposed through the back cap, and secures to the front housing coupling the front housing, the motor housing, and the back cap together.

A power tool is provided that, in one version, includes a front housing that supports an output drive, and a back cap located opposite the front housing. The back cap receives at least one fastener of the plurality of fasteners. A motor housing supports a motor and is located between the front housing and the back cap. The motor includes a rotor that is configured to rotate about a motor axis to drive rotation of the output drive. The fastener is disposed through the back cap, and secures to the front housing coupling the front housing, the motor housing, and the back cap together.

A superconducting flux barrier electric motor, including at least one induced element and at least one conductor, one of the armature or the inductor housing at least one rotor and at least one superconducting induction coil, and the other including at least one arrangement of the electromagnetic coils coaxial with the superconducting induction coil the rotor comprising superconducting pellets mounted radially inside the superconducting coil on an axis of rotation of the motor, where the electromagnetic coils are made of superconducting material and the induced element and the inductor are arranged in an assembly forming a cooling chamber provided with specific cooling means for the superconducting elements of the induced element and the inductor.

A superconducting flux barrier electric motor, including at least one induced element and at least one conductor, one of the armature or the inductor housing at least one rotor and at least one superconducting induction coil, and the other including at least one arrangement of the electromagnetic coils coaxial with the superconducting induction coil the rotor comprising superconducting pellets mounted radially inside the superconducting coil on an axis of rotation of the motor, where the electromagnetic coils are made of superconducting material and the induced element and the inductor are arranged in an assembly forming a cooling chamber provided with specific cooling means for the superconducting elements of the induced element and the inductor.

A coolant system includes a first and a second coolant tank, the first and second coolant tanks are connectable to each other by means of a coolant supply conduit and a first coolant feeding conduit, wherein the first coolant feeding conduit comprises a fluid pump. The coolant system hereby provides an active coolant pressure control with service filling ability.