Siemens Energy, Inc.

Siemens Westinghouse Power Corporation

Siemens Power Generation, Inc.

Randy Edward Whitener

Jiping Zhang

William Cannon Gardner

Peter Jon Clayton

Kevin Michael Light

Stephen Thomas Soto

Larry L Zeller

Thomas Leonard Schuchart

Michael Joseph Rasinski

Robert Gore

Shane Bell

Justin Nathaniel England

Raul Ricardo Rico

Michael D Garmon

Kevin P Bailey

Robert L Murphy

David Earl Hulsey

Thomas L Schuchart

Justin England

Robert R Messel

William Gene Morgan

Terrell H Yon, Iii

Donald Yaffee

Mark A Grobe

James V Johnson

Robert F Lemke

Andrew Adam

Robert W Ralph

Alejandro Felix

Mark Roberts

Christian T Schneider

Grant Hennessey

Neil R Smith

Alan Fortner

Craig Michael Spencer

Brent Mazingo

Henk Roel Jan Van Ravenswaay

Mark Steven Peavy

William C Gardner

A method for repairing a stator core of a generator is presented. The stator core includes laminations grouped into packs. A ventilation spacer is disposed between adjacent packs. Laminations are separated from each other by insulation layers. The ventilation spacer is removed between adjacent packs having a damaged insulation layer between the laminations to locally loosen the laminations in the adjacent packs which allows the damaged insulation layer between the laminations to be repaired. A new ventilation spacer is reinstalled between the adjacent packs where the ventilation spacer being removed to retighten the laminations in the adjacent packs after completion of the repair. The new ventilation spacer is adhesively secured between the adjacent packs.

Method for repairing generator stator core

A false tooth assembly for a generator stator core is presented. The false tooth assembly has a tapered shape including multiple tapered false tooth pieces. The multiple tapered false tooth pieces are installed into a damaged area in a tooth of a lamination of the stator core such that a wide end of the false tooth assembly is disposed into a wide opening of the damaged area and a narrow end of the false tooth assembly is flushed with a narrow opening of the damaged area at a tip of the tooth. The tapered shape of the false tooth assembly enables the false tooth assembly to fill the entire damaged area and to lock the false tooth assembly into the damaged area. The false tooth assembly can be used to repair stator core in any region of the stator core including step iron region without being dislodged during generator operation.

False tooth assembly for generator stator core

An assembly and a method for preventing an axial migration of a spring in a generator rotor are presented. The assembly includes a step pin radially disposed through an amortisseur and inserted into a spring of the generator rotor. The step pin is arranged axially apart from an adjacent radial vent passage and radially extends through the spring into a slot clearance between the spring and a creepage. The amortisseur includes a counter bore to retain a pin head and a pin shoulder. The spring includes a pin hole for a pin body extending therethrough. Diameters of the counter bore and the pin hole are smaller than diameters of amortisseur radial vent aperture and spring radial vent aperture. The step pin prevents an axial migration of the spring in rotor slots.

Assembly and method for preventing axial migration of springs in generator rotors

A method of determining the risk of a stator failure is provided. The stator includes multiple stator coil windings. Each of the windings includes multiple conductive metal strands. The number of strand failures is determined from an image captured by a radiography. A risk analysis is assessed from the determined number of strand failures.

Method of assessing the risk of a stator failure

A radial lead seal assembly of a generator and a method for sealing a radial chamber from an axial chamber of a generator using a radial lead seal assembly are presented. The radial lead seal assembly includes sealing elements disposed around a radial lead to seal an annular space between the radial lead and the radial chamber and thereby seal the axial chamber fluidically from the radial chamber. Conical springs are disposed annularly around the radial lead between the sealing elements and a junction between the radial lead and the axial lead. The radial lead seal assembly includes a nut for exerting a compressive load on the radial lead seal assembly in a radially inward direction such that the conical springs are only partially compressed.

Radial lead seal assembly for a generator and method incorporating the same

A retrofit method for modifying a radial lead seal assembly of a generator and a radial lead seal assembly of a generator are presented. The radial lead seal assembly seals a radial chamber from an axial chamber. The radial lead seal assembly includes sealing elements disposed around a radial lead to seal an annular space between the radial lead and the radial chamber, a coil spring disposed around the radial lead between the sealing elements and a junction between the radial lead and the axial lead, and a nut. The retrofit method includes removing one or more of the sealing elements to define a radial space between the remainder of the sealing elements and the coil spring. Conical springs are inserted in the radial space and only partially compressed under a radially inward compressive load exerted on the radial lead seal assembly via the nut.

Radial lead seal assembly for a generator and a radial lead seal assembly of a generator

A winding for a rotor for use in an electrical generator utilized in the power generation industry. The winding includes a plurality of axial sections and a plurality of transversely oriented end arc sections. An integrated leg section extends from each end arc section to form an associated corner section at an intersection of each leg section and associated end arc section. Each leg section is affixed to an associated axial section at a joint that is spaced apart from an associated corner section such that the joint is not subjected to stress concentration which occurs at the associated corner section.

Rotor winding having a braze joint spaced apart from stress concentration

A system for securing a nut () used to compress a compliant seal () surrounding a radial conductor lead () of an electric generator (). The generator has a rotor () with the radial conductor lead arranged in a radial lead bore () of the rotor and the seal coaxially arranged surrounding the radial lead. A receiving pocket () is arranged in a body of the rotor adjacent to the radial lead bore. The nut is arranged coaxially with the radial conductor lead, the nut including a seal contacting surface () and a ligament () arranged opposite the seal contacting surface, wherein a portion of the ligament is deformed into the receiving pocket to lock the nut against rotation, thereby maintaining a desired degree of compression on the seal.

Nut securing arrangement for electrical generator

A rotor pole crossover connection joint for use in a rotating electrical machine is disclosed. The connection joint integrally couples a bottom rotor coil strap to a rotor pole crossover connector with a single piece connector that reduces, distributes or otherwise tolerates stress concentrations in the connector. A corresponding method of forming a rotor pole crossover connection and a rotor assembly including a rotor pole crossover connection joint are also disclosed.

Rotor pole crossover connection

A method of determining an alignment of a floating seal for a turbo machine, including establishing a reference surface on a rotor of the turbomachine that is essentially perpendicular to an instantaneous centerline of the rotor, establishing a control surface that radially aligns a floating seal member that surrounds the rotor, providing an inflatable member arranged between a stationary portion of the turbomachine and a surface of the floating seal, inflating the inflatable member such that the inflatable member urges the floating seal firmly against the control surface, measuring an axial distance between the floating seal and the reference surface at a plurality of locations, determining a parallelism between the facing surfaces of the floating seal and the rotor based upon the plurality of measured axial distances, comparing the determined parallelism with a predetermined threshold, and adjusting an orientation of the control surface based upon the comparison.

Method and system for adjusting a turbomachine gland seal

An interconnecting assembly for a rotor assembly of a dynamoelectric machine is provided. The interconnecting assembly may be part of a conductive path generally extending from a radially inward section of the rotor assembly to a winding located at a radially outward section of the rotor assembly. The interconnecting assembly may be made up of a flexible member () comprising a bend (). The interconnecting assembly may be further made up of a connector () connected to the flexible member to pass axial and radial forces that develop during operation of the machine. The positioning of the connector relative to the flexible member may be arranged so that an effect of an axial force on a radius of curvature of the bend and an effect of a radial force on that radius of curvature are opposed to one another. This leads to lower peaks of mechanical stress at the flexible member () (e.g., J-strap), which in turn leads to a relatively more durable and reliable conductive path for the rotor assembly of the dynamoelectric machine.

Generator rotor lead path for connecting to a field winding

An improved generator rotor () and a method of repairing an existing generator rotor () are disclosed. Methods consistent with the present invention provide techniques for repairing existing stress-damaged rotors () to remove stress-induced cracks (), without requiring new retaining rings (), to significantly extend the useful life of a generator without the cost and complexity of conventional repair techniques. Improved generator rotors () consistent with the present invention provide a tooth-top design that is more resistant to stress-induced cracking than conventional designs, resulting in new generators with longer useful lives.

Generator rotor

An interconnecting assembly () for a rotor assembly of a dynamoelectric machine is provided. The interconnecting assembly may be part of an electrically conductive path generally extending from a radially inward section of the rotor assembly to a top winding of a stacked winding () located at a radially outward section of the rotor assembly. The interconnecting assembly may include a first connecting member () connected to a radial lead () at the inward section of the rotor assembly. This first connecting member is made up of multiple conductive leaves and includes a flexible bend () positioned to provide a resilient-connection relative to at least a radial direction. The interconnecting assembly may further include a second connecting member () mechanically connected to the first connecting member by way of the resilient connection. This second connecting member is electrically connected to the first connecting member and to the top winding. The second connecting member may include a stiffener () for providing support relative to an outer portion of the bend to increase stiffness and prevent buckling of the bend due to a centrifugal force that develops during operation of the machine.

Generator rotor conductive path for connecting to a top-turn of a winding

Method for repairing generator rotor

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Oviedo, FL, United States of America

Randy Edward Whitener