A permanent-magnet synchronous rotary electric machine for a self-propelled mobile device includes a stator having slots and a winding including at least three phases. The winding is of the type in which the number of turns N in the stator per phase is equal to the number of conductors in a slot, multiplied by the number P of pole pairs multiplied by the number of slots per pole and per phase, all divided by the number of parallel electrical paths of the conductors in a slot and/or divided by the square root of three if the winding is delta-coupled. The number of turns N per phase in the stator is between 9 and 20.

A permanent-magnet synchronous rotary electric machine for a self-propelled mobile device includes a stator having slots and a winding including at least three phases. The winding is of the type in which the number of turns N in the stator per phase is equal to the number of conductors in a slot, multiplied by the number P of pole pairs multiplied by the number of slots per pole and per phase, all divided by the number of parallel electrical paths of the conductors in a slot and/or divided by the square root of three if the winding is delta-coupled. The number of turns N per phase in the stator is between 9 and 20.

A smart ring includes a housing configured to be worn by a user. The smart ring can further include a power source disposed within the housing. The smart ring also can include a charging circuit disposed within the housing. The charging circuit can include a harvesting element configured to charge the power source. The harvesting element can be configured to convert mechanical energy to electrical energy. The smart ring also can include a device at least partially disposed within the housing. The device can be configured to draw energy from the power source. Other embodiments are disclosed.

A smart ring includes a housing configured to be worn by a user. The smart ring can further include a power source disposed within the housing. The smart ring also can include a charging circuit disposed within the housing. The charging circuit can include a harvesting element configured to charge the power source. The harvesting element can be configured to convert mechanical energy to electrical energy. The smart ring also can include a device at least partially disposed within the housing. The device can be configured to draw energy from the power source. Other embodiments are disclosed.

An electric machine having a rotor, stator and at least one winding. The winding defines a first lead having a conductive core and an electrically insulative exterior layer. A connector engaged with the first lead includes a plurality of projections that pierce the exterior layer of the first lead to engage the conductive core. The connector may be C-shaped having a spine and first and second arms with first and second bend lines respectively disposed between the spine and the two arms. Alternatively, the connector may be U-shaped having a spine and first and first and second arms wherein a bend line and a central opening are disposed between the two arms. The first lead extends through the central opening and is grippingly engaged by the connector between the first and second arms. The connector may also be used to securely engage an uninsulated terminal.

An electric machine having a rotor, stator and at least one winding. The winding defines a first lead having a conductive core and an electrically insulative exterior layer. A connector engaged with the first lead includes a plurality of projections that pierce the exterior layer of the first lead to engage the conductive core. The connector may be C-shaped having a spine and first and second arms with first and second bend lines respectively disposed between the spine and the two arms. Alternatively, the connector may be U-shaped having a spine and first and first and second arms wherein a bend line and a central opening are disposed between the two arms. The first lead extends through the central opening and is grippingly engaged by the connector between the first and second arms. The connector may also be used to securely engage an uninsulated terminal.

In some embodiments, a system includes a machine segment that includes multiple coils. Each coil is electrically isolated from the other coils in the machine segment, and each coil is electrically coupled to at least one electrical terminal to provide electrical access to the coil. Each electrical terminal provides electrical access to the coil to which it is electrically coupled such that the coil can be removably electrically coupled to an electrical circuit. The machine segment is also configured to be removably mechanically coupled to a second machine segment to form at least a portion of a stator or a portion of a rotor.

In some embodiments, a system includes a machine segment that includes multiple coils. Each coil is electrically isolated from the other coils in the machine segment, and each coil is electrically coupled to at least one electrical terminal to provide electrical access to the coil. Each electrical terminal provides electrical access to the coil to which it is electrically coupled such that the coil can be removably electrically coupled to an electrical circuit. The machine segment is also configured to be removably mechanically coupled to a second machine segment to form at least a portion of a stator or a portion of a rotor.

A system and a method for producing fracturing fluid, comprising: receiving source fluid from one or more inlet manifolds of a single transport, driving a first pump mounted on the single transport to route the source fluid from the inlet manifolds into a hydration tank mounted on the single transport, driving a second pump mounted on the single transport to route hydrated fluid produced by the hydration tank to a blending tub mounted on the single transport, and discharging fracturing fluid produced by the blending tub to one or more outlet manifolds of the single transport.

Providing electric power distribution for fracturing operations comprising receiving, at a transport, electric power from a mobile source of electricity at a first voltage level and supplying, from the transport, the electric power to a fracturing pump transport at the first voltage level using only a first, single cable connection. The first voltage level falls within a range of 1,000 V to 35 kilovolts. The transport also supplies electric power to a second transport at the first voltage level using only a second, single cable connection.