155results about "Prevention/reducing eddy-current losses in winding heads" patented technology

An automotive alternator including a rotor having a plurality of poles; a plurality of phases in operable communication with the plurality of poles; and a stator core in operable communication with the rotor, the stator having a number of slots defined by:

S=(P×PH)+((M×PH)+N)

where S=number of slots P=number of poles PH=number of phases M=a whole integer greater than or equal to 0 N=a whole integer selected from a group of integers ranging from, and including, 1 through the number of phases minus 1. A method for reducing magnetic noise in an automotive alternator includes selecting a number of poles, selecting a number of phases, selecting a number of stator core slots, the foregoing selections interacting in the automotive alternator to produce an order of frequency of a tangential force different than any multiple of the number of phases and different than an order of frequency of a radial force of the alternator.

An electromechanical apparatus includes: a rotor including a central shaft and permanent magnets disposed around a cylindrical surface along an outer circumference of the central shaft, and a stator including hollow electromagnetic coils disposed around a cylindrical surface along an outer circumference of the permanent magnets and a pipe member having a hollow cylindrical shape and disposed between the permanent magnets and the electromagnetic coils, wherein the pipe member is made of a carbon fiber reinforced plastic, and the carbon fiber reinforced plastic is formed by weaving carbon fiber bundles formed of bundled carbon fibers.

The present application has a purpose to provide a conductor wire for motor capable of improving durability against bending, and a coil for motor using the conductor wire for motor. One aspect of the invention, therefore, provides a conductor wire for motor comprising a fine wire assembly and a coating member covering an outer peripheral surface of the fine wire assembly, the fine wire assembly consisting of a plurality of fine wires assembled in a bundle, and each of the fine wires including a conductor and an insulating part provided on an outer peripheral surface of the conductor, wherein the coating member is made of metal, and the coating member has an electrical resistance value larger than an electrical resistance value of the conductor.

The invention provides a motor convenient for fluid flowing. The motor comprises stator windings and ventilation channel steel. According to the technical points, two pieces of rectangular ventilation channel steel are arranged between two adjacent stator windings of one group, one piece of trapezoid ventilation channel steel is arranged between one group of two adjacent stator windings and another adjacent group of two stator windings, and the width radio of the upper half part to the lower half part of the trapezoid ventilation channel steel is 2:1. The ventilation channel steel after changing changes a lot both in shape and distribution, and the lower part of each piece of trapezoid ventilation channel steel is narrowed, so that the flowing range of a fluid is increased, and the flowing speed of the fluid is increased; the eddy current loss is reduced due to the change of the direction of the fluid, and the concave-shaped design of the upper part of the trapezoid ventilation channel steel further increases the flowing speed of the fluid; in addition, the distribution mode of the trapezoid ventilation channel steel and the rectangular ventilation channel steel facilitates the heat exchange between the inner part and the outer part of the motor, the temperature rise of the motor is reduced, and heat loss through convection is facilitated.

A power generator (20) includes a rotor (22), and a stator (23) surrounding the rotor and having opposing ends. The stator (23) includes a stator core (21) and a plurality of windings (28) carried by the stator core creating an undesired axial magnetic field component adjacent the opposing ends of the stator. The power generator (20) may also include at least one counteracting magnetic field generator (30) associated with at least one end of the stator (23) for generating a counteracting magnetic field for counteracting the undesired axial magnetic field component.

A shield (2) for components on the stator (10) of a three-phase generator (1), with at least one pressure plate (3) or the like being arranged at the end on the stator core (6), is distinguished in that the shield (2) is composed essentially of a magnetically permeable composite material of low electrical conductivity. A method for production of a shield such as this includes the pressing and heat-treatment of appropriate composite particles. This overcomes the disadvantages of the prior art and provides a shield for components on the stator of a three-phase generator, which reduces the additional losses and prevents a build up of heat. Furthermore, this results in a solution which can be produced and installed easily and at low cost, and which can also easily be retrofitted to existing installations. Furthermore, three-dimensional finite element design methods can be used for optimized guidance of the magnetic field.

A rotating electric machine including a stator including a stator core and a stator coil wound around the stator core, and a rotor including a rotor core arranged coaxially and radially in a face-to-face relationship with the stator core and a field coil wound around the rotor core. Both axial end portions of the rotor core project more axially outward than respective axial end faces of the stator core. The rotor core has a cutout surface between one of the axial end faces of the rotor core and an outer peripheral surface of the rotor core. A corner at which the cutout surface and the outer peripheral surface intersect is not more axially outward than either of the axial end faces of the stator core.

A system and a method are presented. The system includes an electrically conducting material and an electrical insulation system. The electrical insulation system includes a layered insulation tape that has a first layer and a second layer. The first layer includes a mica paper and a binder resin in a range from about 5 wt % to about 12 wt % of the insulation tape. The second layer includes a composite of layered nanoparticles dispersed in a polyetheretherketone (PEEK) matrix. The second layer laminates the first layer. The method includes attaching the first layer and the second layer with or without the addition of further resin; using the layered insulation tape as a turn insulation and ground wall insulation for an electrically conducting material; and impregnating the system with a nanofiller-incorporated resin by a vacuum pressure impregnation method, to form an insulation system within the system.

A rotating electrical machine, especially a turbogenerator, includes a rotor and a stator, which concentrically surrounds the rotor and is terminated at each of the two axial ends by a laminated press plate (14), which is constructed from a stack of individual press plate laminates (30). The electrical properties are improved by providing the press plate laminates (30) at least partially with slits (26) for reducing the eddy current losses.

A rotating electric machine having a magnetic circuit which in one of the parts of a rotor and a stator of the machine comprises an element (1) having a slot for a winding of layers (14, 16) of cables (9) extending substantially axially and arranged substantially radially outside each other, said cables comprising an inner conductor (10) comprising a plurality of strands (13) and an insulation (11) arranged outside thereof, has a larger share of strands of the cables closest to the other part of the rotor and the stator electrically insulated (15) with respect to each other than in the cables in the cable layer (16) most far away from said other part.

A rotation machine is configured such that permanent magnets and pole shoes holding the permanent magnets at the outer diameter side of the permanent magnets are provided for a rotor, and an outer diameter size (Ra) in the axial end portion of the pole shoe is made smaller than an outer diameter size (Rb) in the axial center portion.

In an electric rotating machine, for reducing losses that occur in clamping plates and their shield, the electric rotating machine includes a rotor formed with field winding wound around a rotor core, a stator placed opposite to the rotor at a predetermined space and formed with stator winding wound around a stator core formed by stacking multiple magnetic steel sheets in the axial direction, clamping plates clamping and retaining the stator core from both axial end parts thereof in the stacking direction of the magnetic steel sheets, and a magnetic shield placed around the clamping plates to shield flux leakage flowing into the clamping plates, and the magnetic shield is formed of a cylinder of stacked steel sheets stacked in a form of a cylinder about the rotor shaft and powder magnetic core segments and powder magnetic core segments having portions which are stuck to the cylinder of stacked steel sheets on the stacking cross section, and arranged to cover side surfaces and an inner surface of radial direction of the clamping plates.

The invention provides for flux-shields wrapped around the flux-sources at the core-end of large power generators. They prevent overheating of all core-end parts under all abnormal conditions of operation. A first flux-shield is an electrically conductive cylindrical shell concentric with rotating end-windings, held outside the retaining ring. The rotating flux source induces eddy currents in the first flux-shield whose flux repels the source flux. Only a small part of the rotating source flux is hence received by all the core-end parts, thereby greatly reducing their temperatures. A second flux-shield comprises an electrically conductive tape wrapped over the ground-insulation of stator bars protruding from the core. Alternating flux generated by the stator bars induces eddy currents in the second flux-shield whose flux repels the source flux. Only a small fraction of the source flux is hence received by all core-end parts, thereby greatly reducing their temperatures. The present invention replaces multiple devices such as step-iron, flux-shields, flux shunts, short-rotors etc, used in the prior-art with only two devices. As a result, the design of the core-end is simplified and the cost of the generator is reduced.

An AC asynchronous motor with circumferential windings includes three phases of stator magnetic cores (145, 146 and 147), three phases of circumferential windings (167, 168 and 169), an a asynchronous motor rotor and accessories including a casing and a bearing. the three phases of stator magnetic cores are arranged axially phase by phase, and each phase of stator magnetic core comprises a cylindrical magnetic core, stator magnetic poles arranged in parallel with the axial direction of the cylindrical wall and magnetic circuit connectors; the magnetic poles form a circumferential range, a gap exists between the adjacent magnetic poles, one end of the magnetic pole and one end of the adjacent magnetic pole are connected to the two ends of the cylinder via the magnetic circuit connectors respectively, and the circumferential winding is embedded into an annular space between the magnetic poles and the inner cylindrical wall; and three phases of rotor magnetic cores are aligned and connected in series along the axial direction, busbars in the three phases of rotor slotways share short-circuit rings at the two ends, under the three-phase AC of the three-phase circumferential windings, induction currents of the busbars of the rotors bear a force in a mixed manner, self-startup operation is realized, and loss and end-portion loss of traditional windings are avoided. Thus, the AC asynchronous motor has the advantages including little magnetic flux leakage, simple structure, reduced copper material, less heating, high efficiency and reliability and energy-saving performance.

A generator rotor core (54) carrying superconducting windings (60) and having a shield (426) over the superconducting windings (60) to prevent external magnetic fields from impinging the windings. Axial shield edges (430/434) mate with corresponding features of the rotor core (54) or with structures affixed to or supported by the core (54) to support the shield (426).

The invention relates to a winding tooth (3) for a component (2) of an electrical machine (1), in particular for a stator and/or a rotor, comprising: a tooth shaft for being wound with a winding coil (4); and a tooth head (5) which is arranged at one end of the tooth shaft with respect to a winding axis; wherein one or more slots (14) are provided at at least one end section of the winding tooth (3), said slots extending along the winding axis through the tooth head (5), wherein the end section corresponds to a region at one or both ends of the winding tooth (3) along a transverse direction which runs substantially perpendicular to the winding axis.

A motor driving device includes N units (N is a natural number equal to or greater than 2) of inverters configured to control N units of motors, respectively, a×N units (a is a natural number) of cables configured to allow connection between the N units of inverters and the N units of motors, respectively, and a PWM signal output unit configured to transmit a PWM signal to the N units of inverters. The N units of inverters and the a×N units of cables are divided into M groups (M≤N). The PWM signal output unit outputs the PWM signal for driving at least one inverter belonging to each group of the M groups so that the PWM signals have phase differences shifted by 360 degrees/M among the groups.