Westinghouse Electric Corporation

Arthur Mulach

Raymond M Calfo

George F Dailey

Warren W Jones

Gerald R Alkire

Frank P Fidei

James G Minto

A means for preventing harmful interlaminar electrical currents from flowing within the stator core of dynamoelectric machines is disclosed. By providing an insulation between the building bolts and the step iron portion of the stator core, current flow is inhibited in the event that a portion of the stator core is electrically shorted between adjacent laminations. Electrical communication between the building bolt and the stator core laminations is prevented by an insulated cylinder disposed about the building bolt and cooperatively associated with two layers of plates which are disposed on the two axial extremes of a preselected segment of the stator core laminations.

Apparatus for preventing overflux damage to stator cores

A dynamoelectric machine's segmented baffle assembly comprises a baffle ring which is bolted to a back-up plate disposed in the stator core. The annular-shaped baffle ring is formed from a plurality of arcual segments, each segment secured by at least one of said bolts. For low flow rates of coolant gas, the air gap can be further reduced by means of a teflon insert located on the inner circumferential surface of the baffle ring. For expeditious access to the rotor assembly, only one of said segments need be.

Dynamoelectric machines segmental air gap baffle assembly

Laminated flux screens disposed between finger plates and end plates of a generator to reduce the axial flux striking the end region of the generator core.

Dynamoelectric machine with flux screen

In a generator a plurality of laminations are disposed adjacent the stator teeth to extend radially outwardly from the rotor and generally perpendicular to the stator laminations to form a flux shunt to prevent fringing flux from entering the core perpendicular to the stator laminations.

Laminated flux shunt for dynamoelectric machine stator

A flux sensor is provided for measuring magnetic flux in laminated cores, and especially for measuring the axial flux in the end regions of the stator cores of large generators. The sensor comprises a flat, multi-turn coil of fine wire enclosed in an insulating enclosure which includes a pressure-supporting member of greater thickness than the coil. The sensor is thin enough to be placed between the laminations of a generator core and the high clamping pressure is carried by the pressure-supporting member which protects the coil. The leads are flat conductors brought out between the laminations to the periphery of the core. Such a sensor can remain permanently embedded in the core since it does not effect the core structure.

Magnetic flux sensor for laminated cores

A system for ensuring uniform axial expansion of a dynamoelectric machine's stator core subjected to elevated temperatures. The stator core constitutes axially adjacent ferromagnetic laminations held in axial compression by through-bolts axially extending through an intermediate portion thereof and building bolts situated in notches formed in the radially outer periphery of the laminations. The building bolts are secured to bore rings which circumferentially encircle and provide support for the stator core. The bore rings are rigidly secured in the axial direction by structural members connected to the bore rings and surrounding machine frame. Nuts disposed on each axial end of the through-bolts are torqued to allow at first axial expansion of the core while maintaining a selected degree of axial compression of the laminations during operation at elevated temperatures. Thermal axial expansion of the building bolts is restrained by their securement to the bore rings and the bore rings' axial securement to the dynamoelectric machine's frame. A spring is disposed on each axial end of the building bolts between the laminations and a building bolt nut. Suitable selection of the spring's force constant and tightening torque for the building bolt nuts permits a second axial expansion of the lamination's outer periphery which is at least as great as the first axial expansion of the lamination's intermediate portions. Uniform axial expansion of the lamination portions between the outer periphery and intermediate portion is provided by a rigid core support plate radially disposed between and intersected by the through-bolts and building bolts.

System for providing uniform axial expansion of a stator core

Improved cooling is provided for the end regions of the stator core of a large dynamoelectric machine. For this purpose, a solid rigid vent plate is placed in contact with the finger plate at each end of the core. The vent plates are non-magnetic plates of the same configuration as the core laminations and have radial grooves in at least one surface. Coolant gas flows through the grooves to directly cool the finger plate and the end laminations of the stator core.

Stator core cooling for dynamoelectric machines

Disclosed is a dynamoelectric machine with a tubular shaped stator assembly having a generally cylindroid rotor assembly mounted therein. There is a clearance between the outer circumference of the rotor and the inner circumference of the stator for the passage of cooling gas. On one end of the stator assembly there is mounted a dual position air gap baffle assembly. In one position the baffle assembly will regulate the flow of cooling gas in the clearance space between the dynamoelectric machine's stator and rotor; and in the other position, there is a keystone shaped opening which will make the rotor assembly accessible.

Growing community of inventors

Penn Hills, PA, United States of America

Arthur Mulach