Abstract:
An induction rotor assembly having conductive bars is provided. The assembly comprises a lamination stack comprising a body having a first end and second ends to define a longitudinal axis. The body has an outer circumferential portion extending from the first end to the second end. The outer portion has a plurality of walls defining open slots formed from the first end through the second end. The assembly further comprises a first ring disposed on the first end and a second ring disposed on the second end. The assembly further comprises a plurality of conductive bars extending between the first and second rings. Each conductive bar is disposed in one of the slots such that the respective conductive bar is in contact with the lamination stack and connects the first and second rings. Each bar comprises an inner portion and a conductive outer skin disposed about the inner portion.
Abstract:
Stator cores and methods for fabricating stator cores are provided. An exemplary stator core includes a stack of laminations. Each lamination in the stack of laminations comprises a yoke and a plurality of tooth segments fixed to the yoke.
Abstract:
A rotor casting includes a lamination stack and a cast structure including proximal and distal cast end rings respectively adjacent proximal and distal end faces of the lamination stack. Cast axial ribs are distributed radially on a peripheral surface of the lamination stack and extend between the proximal and distal cast end rings. Cast feed members extend axially from the proximal cast end ring and are respectively positioned radially between an adjacent pair of axial ribs. In one example, cast bar segments integral to the proximal and distal cast end rings are formed in axial slots of the lamination stack. In one example, a bar insert in each axial slot has insert ends that extend respectively from the proximal and distal end faces of the lamination stack and are fully encapsulated respectively in the proximal and distal cast end rings. A method of forming the rotor casting is provided.
Abstract:
A rotor for an electromagnetic machine and a method of assembling the rotor are provided. In one embodiment, the rotor includes a lamination stack disposed about a rotational axis a plurality of conductor bars disposed within corresponding slots formed in the lamination stack and extending beyond the longitudinal ends of the lamination stack. End rings are positioned at either end of the lamination stack and define a plurality of openings configured to receive the ends of the conductor bars. Each end ring includes separate inner and outer concentric rings. The inner and outer rings define radially outer and inner surfaces configured to abut one another and each of the concentric rings defines a portion of each conductor bar opening in the end ring.
Abstract:
A system for offsetting a CNC machining process includes transferring compensation variables through registers in fixed G-code programming of the CNC machine and offsetting the CNC machine without altering fixed G-code programming. Global compensation variables are applied to all feature programs of the CNC machining process, and local compensation variables are applied to only individual features or groups of features. The machine shifts position in response to the compensation variables.
Abstract:
An electrical part testing system for evaluating quality of an insulated electrical part, including a computer-controlled switching apparatus for providing an original voltage to the electrical part automatically according to a pre-established testing scheme calling for provision of voltage to each phase of the part, in turn, while grounding the other phases of the part. A high-frequency filter for receiving receive the original voltage, receiving a load voltage emanating from the electrical part in response to the part receiving the original voltage, and filtering the original voltage from the load voltage to isolate any partial-discharge voltage added to the original voltage by the electrical part while the part is being electrified by the original voltage, yielding a filtered signal. A computing device determines, based on a comparison of a peak amplitude of the partial-discharge inception voltage to a voltage threshold, the quality of the electrical part being tested.
Abstract:
An arc welding/brazing process is disclosed that is useful to join together a first copper piece and a second copper piece without damaging more heat-sensitive materials that may be located nearby is disclosed. The arc welding/brazing process includes using a non-consumable electrode wire, which electrically communicates with a weld control in a straight polarity orientation, to strike an arc across a gap established between a leading tip end of the electrode wire and the first copper piece. The current that flows through the arc when the arc is established heats the first copper piece such that the first copper piece becomes joined to a second copper piece. The joint between the first copper piece and the second copper piece may be an autogenous weld joint or a braze joint.
Abstract:
An induction rotor assembly includes a laminated stack, conductor bars, a first end ring, and a second end ring. The laminated stack includes a body with a first end, an opposing second end, and an outer circumferential surface extending from the first end to the second end along a longitudinal axis. The conductor bars are disposed within grooves in the outer circumferential surface. Each conductor bar includes a first conductor end and a second conductor end extending beyond the ends of the laminated stack. The first conductor end and the second conductor end of each of the conductor bars includes a serrated surface having serrations. The first end ring and second end ring interlock with the serrated surface of the conductor ends. The conductor bars extend between the first end ring and the second end ring.
Abstract:
Methods and systems for detecting partial discharge in a stator for an electric motor are provided. An exemplary method includes applying a high voltage AC sinewave input signal to the stator and energizing at least one winding therein. The method includes sensing a first resulting load signal occurring in the stator with a first device and filtering the first resulting load signal to form a first high frequency signal indicating any partial discharge (PD) voltage occurring in the stator. The method also includes sensing a second resulting load signal occurring in the stator with a second device and filtering the second resulting load signal to form a second high frequency signal indicating any partial discharge voltage occurring in the stator. Further, the method includes processing the first and second high frequency signals to form a processed signal indicating whether partial discharge occurred.
Abstract:
An induction motor includes a stator and a rotor. The stator is configured to generate a rotating magnetic field. The rotor is disposed inside the stator, separated from the stator by an air gap, and is configured to rotate around an axis in response to the rotating magnetic field. The rotor includes a rotor core, multiple end rings, and multiple collars. The end rings are attached at opposite ends of the rotor core. Each end ring has one of multiple regions disposed outside the air gap. Each region has an outer surface. The collars are attached in a prestressed condition around the outer surface of each region. The prestressed condition is configured to maintain a compressive stress in the end rings at a maximum-designed rotational speed of the rotor.