Abstract:
A sleeve about an electric machine rotor core and the plurality of permanent magnets has a fiber-reinforced composite layer about the rotor core and the plurality of permanent magnets. At least a portion of the sleeve about the rotor core and the permanent magnets has a coefficient of thermal expansion that is substantially equal to the aggregate coefficient of thermal expansion of the rotor core and the plurality of permanent magnets.
Abstract:
A rotor for an electric machine can be constructed with magnet segments having a uniformly oriented direction vector component. In certain instances, a two-pole rotor includes a rotor hub and a plurality of permanent magnet segments affixed to a perimeter of the rotor hub. The magnetic segments defining a substantially cylindrical outer surface of the rotor. The magnet segments each have a magnetic field with a direction vector component, and the direction vector components of the magnet segments affixed to the perimeter of the rotor hub are substantially parallel and oriented in substantially the same direction.
Abstract:
A reconfigurable power system that includes a gas turbine, flywheel, a first electric machine coupled to the gas turbine, a second electric machine coupled to the flywheel, the first and second electric machines being substantially similar in configuration, a first power device for coupling power from the first electric machine to a power grid, a second power device coupled to the second electric machine for driving the flywheel and coupling power from the second electric machine to the power grid, and a switch for coupling either the power generated by the first electric machine or the second electric machine to the grid.
Abstract:
A method and apparatus are provided for modeling an electric motor. The method includes the steps of interpolating a flux density for each angular position within an air gap of the electric motor from a predetermined air gap and tooth magnetization magnetomotive force versus air gap flux density curve, decomposing the interpolated flux density into a set of harmonic components using a fast Fourier transform and determining a flux density error function from the decomposed set of harmonic components.
Abstract:
A stator core for a stator of an electrical machine includes an elongate stator yoke having an interior surface that defines an axial central opening through the stator yoke. The interior surface further defines a plurality of axial channels about a perimeter of the central opening. A plurality of stator teeth are retained in the plurality of axial channels and spaced apart from one another to define to define axial channels to receive windings of the stator.
Abstract:
An apparatus includes a rotor and a magnet disposed on the rotor. The apparatus also includes a pole cap proximate to the at least one magnet disposed on the rotor. The pole cap is magnetically coupled to the magnet and has a laterally asymmetric profile.
Abstract:
An electric machine system includes an electric machine and a companion device. The electric machine has a stationary member and a movable member that, by interaction of magnetic fields, at least one of moves relative to the stationary member or generates electricity when moved relative to the stationary member. One of the stationary member and the movable member comprising a permanent magnet. The companion device is coupled to the electric machine to communicate mechanical movement with the movable member. In certain instances, the electric machine system has adaptations for operation of the electric machine system subsea and/or in a corrosive environment. The electric machine includes a stator that carries a conductive winding having multiple coils. A first subset of the coils are in a first configuration, and a second subset of the coils are in a second configuration. In some implementations, the first configuration is a lap winding configuration, and the second configuration is a concentric winding configuration.
Abstract:
A stator for an electric machine includes multiple conductive coils. Each coil defines a loop that extends axially through the elongate core, exits the core through an end face, and reenters the core through the end face. A first subset of the coils collectively form a first radial layer axially exterior the core and a third radial layer axially exterior the core. Each coil in the first subset resides in both the first layer and the third layer. A second subset of the coils collectively forms a second radial layer axially exterior the core and a fourth radial layer axially exterior the core. Each coil in the second subset residing in both the second layer and the fourth layer.
Abstract:
A rotor for an electrical machine includes a rotor hub and a plurality of permanent magnet segments affixed around a perimeter of the rotor hub. A first plurality of the permanent magnet segments have a substantially uniform arcuate span and are formed of a single unitary piece of material. A multi-piece permanent magnet segment includes at least two pieces, each having a smaller arcuate span than the first plurality of segments. The magnetization direction vector of one piece different than the magnetization direction vector of at least one other piece in each multi-piece segment.
Abstract:
A rotor for an electrical machine includes an elongate rotor core assembly comprising a rotor core and a plurality of permanent magnets arranged in a plurality of rings around the rotor core. A composite sleeve resides around the rotor core assembly. The sleeve includes a primarily axially-oriented outer layer and an intermediate layer beneath the outer layer. The intermediate layer includes a circumferential band of composite material positioned orthogonal to a longitudinal axis of the rotor core assembly.