A method is provided for balancing rotors (10) of electrical machines. Each rotor (10) has a shaft (11) and at least one laminated core (12) is arranged on the shaft. The method includes providing blanks (13) with a length (l) that is smaller than an outside diameter (d) of the laminated core (12) of the rotor (10). A magnitude and orientation of an initial unbalance of the rotor (10) then is ascertained. A recess (15) then is made in each blank (13) spaced from the center of gravity by a distance depending on the magnitude of the ascertained initial unbalance. The blank (13) is mounted by fitting the recess (15) on the shaft (11) of the rotor (10) and mounting the processed blank (13) on the rotor (11) in an angular position that is dependent on the orientation of the ascertained initial unbalance.

Systems and methods for reclaiming and remagnetizing permanent magnet motors such as may be used in electric submersible pumps. In one embodiment, a method includes removing a permanent magnet rotor assembly from a motor and heating the rotor to burn off the residual oil and evaporate water in between laminations of the rotor and on the rotor surface. The rotor should be heated to a temperature that is above a flashpoint of oil on the rotor and below a Curie temperature of a material of a set of permanent magnets in the rotor (e.g., at least 600° F. for at least 12 hours). The heating may partially or fully demagnetize the permanent magnets in the rotor. The exposed surfaces of the rotor are then cleaned and the permanent magnets in the rotor are remagnetized using a specialized magnetizing fixture.

A rotor for connection to a stationary member for use in an electric machine is provided. The rotor includes a body defining a center of rotation of the body. The body further defines a first surface extending in a direction generally perpendicular to the center of rotation. The rotor also includes a magnet connected to the body and an adhesive. The adhesive is positioned between the magnet and the body. The adhesive is adapted to assist in securing the magnet to the body. The first surface of the body is adapted to permit removal of material from the body and to assist in balancing the rotor.

A rotor includes an assembly of laminations including a plurality of radially-projecting poles, a winding of electrically conductive wires to be wound around each pole by means of wire-guiding heads arranged axially on either side of the lamination assembly. A guiding head support is inserted between the lamination assembly and each guiding head such that: an internal radial face of the support abuts against an external radial face at an axial end of the lamination assembly; and a peripheral surface of the support, which projects axially outward from the internal radial face of the support, is in contact with a contact face of the guiding head that is orientated radially outward from same, the guiding head abutting against the peripheral surface of the support.

A rotor 10 rotatable around a predetermined centerline direction includes: a columnar magnet 12; and a first rotating shaft 70 with a first columnar part 71 and a cylinder-shaped first cylindrical part 72 covering a part of a first outer circumferential surface 913 of the magnet 12, wherein the first outer circumferential surface 913 of the magnet 12 and a first inner circumferential surface 721 of the first cylindrical part 72 of the first rotating shaft 70 are joined, and a first end surface 912 of the magnet 12 and a first end surface 731 of the first rotating shaft 70 are not joined.

A rotor according to an embodiment includes a cylindrical magnet, a holder, and a balance adjusting portion. The cylindrical magnet has a bore portion into which a rotary shaft is inserted, the inner diameter of the bore portion being larger than the outer diameter of the rotary shaft. The holder is made of resin, and has a tubular portion formed in the bore portion of the magnet and a protruding portion protruding from the magnet in the rotation axis direction, the holder being press-fitted onto the rotary shaft. The balance adjusting portion is press-fitted onto the rotary shaft with the protruding portion interposed therebetween.

A rotor according to an embodiment includes a cylindrical magnet and a balance adjusting portion. The balance adjusting portion is provided to at least one end portion of the magnet in a rotation axis direction, and is used for adjusting rotational balance of the rotor. The balance adjusting portion has a first member that is in contact with an end portion of the magnet and a second member press-fitted onto the rotary shaft with the first member interposed therebetween.

An induction machine with localized voltage unbalance compensation is disclosed. The use of an induction machine with a voltage unbalance correction compensator (VUC) may be used to maintain proper working conditions of the machine during intervals of voltage unbalance.

An electric drive unit and method of assembling the same is disclosed. The electric drive unit includes a rotor having a rotor shaft, and gear shaft, where the rotor shaft is inserted into the gear shaft. The gear shaft is supported by two bearings, while the rotor shaft supported directly at one end by a bearing and at the other by the gear shaft. A wave spring is also disclosed that provides an axial loading to the rotor shaft. Also disclosed is a balancing ring secured to an end of the rotor via a locknut. The balancing ring can be machined in order to balance the rotor. The rotor shaft can be connected to the gear shaft via a spline connection. The rotor shaft can bear against the gear shaft via a pilot journal and pilot bore defined on the rotor shaft and gear shaft respectively.

An alternator assembly includes a crankshaft that is rotatable about an axis. A rotor is coupled with the crankshaft and is rotatable about the axis in conjunction with the crankshaft. A plurality of magnetic segments is disposed circumferentially about the rotor. Each of the plurality of magnetic segments includes one or more portions having one of a north or south polarity and at least one of the portions on one of the plurality of magnetic segments is configured as a datum section. The datum section has varied characteristic from the remaining one or more portions of the plurality of magnetic segments. A stator includes a plurality of stator poles that includes first and second groups of poles each having respective windings on each pole. The first and second groups are separated by a pair blank poles. A Hall Effect sensor extends between and is supported by the blank poles.