General Electric Canada, Inc.

General Electric Company

Canadian General Electric Company Limited

Other

General Electric Copmay

Robert Henry Rehder

Richard Kenneth Barton

Michael Walter White

Melvin George Johnson

Bruce William Mills

Gerald Burt Kliman

James Harold Ferguson

James H Dymond

David R Boothman

Robert Edward Draper

Bernard John Moore

Everett C Elgar

Yangxin Li

Wayne Jerome Martin

Michael Stutt

G Paul Jones

A rotary transformer has a bus duct assembly that extends through the hollow shaft of a rotary transformer from collector or slip rings positioned above a drive motor for the rotary transformer to end windings of the rotor positioned most remote from the drive motor. By positioning the leads of the bus duct connection with the rotor end windings on the rotor end windings most remote form the drive motor, the shaft strength and integrity is not reduced due to the torque applied by the drive motor. Further, the shaft is formed from two coupled shaft sections and the bus duct assembly comprises two L shaped sections each positioned substantially within a corresponding shaft section. The bus duct sections are interconnected to complete the bus duct assembly making it simpler to remove the first or upper shaft section from the second or lower shaft section during field servicing. Further, the use of the two bus duct sections within the shaft coupled together simplifies assembly of each bus duct section within its corresponding shaft section.

High power rotary transformer with bus duct assembly

An electrical current collector system has an electrically conductive slip ring mounted to a rotatable shaft and a fixed conducting ring assembly forming a partially enclosed AC high voltage electrical current conductive ring channel in which slip ring contacting members are mounted. A compartment at ground potential at least partially encloses the slip ring and the fixed conducting ring assembly. A source directs a fluid into the compartment so that the fluid travels through into the conductive ring channel to perform at least one of cooling and cleaning of the slip ring contacting members. A hollow conically shaped insulator has a frustum with a narrower cross-sectional opening connected to the conductive ring channel and a larger diameter cross-sectional portion passing through and connected to the compartment for exhausting the fluid from the current conductive ring channel.

Electrical current collector cleaning and cooling for high voltage rotating machines

A rotary transformer system ( ) comprises a rotatable shaft ( ) having at least one and preferably plural electrically conductive slip rings ( ) mounted thereon. The slip rings ( ) of the phase planes are electrically connected to their respective windings on rotor assembly ( ) by the bus conductors ( ). The bus conductors ( ) extend through respective phase isolated bus ducts ( ) formed interiorly in rotatable shaft ( ). The bus ducts ( ) have a buffer ( ) provided therebetween so that the bus ducts ( ) are not in physical contact, but are spaced apart and separated. A mouth ( ) and annulus ( ) of each bus duct ( ) extend through a cover plate ( ). The cover plate ( ) is secured by fasteners ( ) through insulated spacers ( ) and is held slight aloft above the circumference of rotatable shaft ( ), thereby insulating cover plate ( ) from rotatable shaft ( ). The cover plates ( ) of adjacent bus ducts ( ) are electrically connected by a flux plate ( ). The flux plate ( ) extends around the exterior of rotatable shaft ( ) and is secured to rotatable shaft ( ) by fastener assemblies ( ). Each phase conductor ( ) is thus in its own grounded metal enclosure, e.g., bus duct ( ). The isolated phase bus ensures that any fault or electrical failure or arc-over will occur first to ground before becoming a phase to phase fault.

Bus duct assembly for high-power rotary current transformer system

An isolated phase bus duct joint assembly couples together first and second phase bus duct sections where each section has an interior bus conductor surrounded by an outer housing. The joint assembly couples end portions of the interior bus conductor and has first and second conductor coupling portions each extending from the end portion of one of the interior bus conductors. Each coupling portion has a reduced outside dimension relative to the interior bus conductors. The joint assembly has a plurality of movable electrical contact fingers mounted by spring loaded adjustment fasteners around the outside surface of the first conductor coupling portion. Each of the fingers extends beyond the first conductor coupling portion for engagement with the outside surface of the second conductor coupling portion. The spring loaded adjustment fastener has a threaded stem passing through the finger and the first inner conductor coupling portion. The stem has an adjustable head engaging an outer surface of the finger and a compression spring mounted over the stem to engage the inside surface of the first inner conductor coupling portion. The heads and stems are adjusted relative the compression spring to urge the fingers into locking engagement with the first and second coupling portions. This advantageously results in no substantial increase in electrical clearance required between the inner bus conductor&scirc; and the outer housing. Further, the heads may be backed off to provide for de-coupling or separation of the joint.

Isolated phase bus duct joint assembly

An electrical current collector system ( ) comprises a rotatable shaft ( ) having at least one and preferably plural electrically conductive slip rings ( ) mounted thereon. For each phase, a slip ring is paired with a fixed conducting ring assembly ( ). The fixed conducting ring assembly forms an envelope within which slip ring-contacting members are situated. The slip ring-contacting members can take many forms, including brushes ( ) or rollers ( ). The fixed conducting ring assembly comprises a first conducting plate ( T) and a second conducting plate ( B) positioned parallel to one another to form a conductive ring channel ( ) therebetween. The slip ring-contacting members ( ) are mounted in the conductive ring channel. An at least partially transparent wall ( W) extends between the first conductive plate and the second conductive plate of the fixed conducting ring assembly to further define the conductive ring channel and permit visual inspection of the slip ring-contacting members. An air flow gap ( ) exists is preferably provided between the slip ring and the fixed conducting ring assembly. The envelope acts as an electrostatic shield or Faraday cage. The envelope is a high voltage envelope which puts the slip ring-contacting members and other components within the envelope at a same high voltage as the fixed conducting ring assembly. Each pair of fixed conducting ring assembly and slip ring is substantially enclosed in its own grounded compartment ( ) for providing electromagnetic shielding.

Envelope for slip-ring contacting members in high-power rotary current collector system

An electrical current collector system includes a rotatable shaft ( ); an electrically conductive slip ring ( ); and a slip ring support assembly ( ). The slip ring support assembly ( ) comprises plural post insulators ( ) spaced radially about the rotatable shaft for attaching the conductive slip ring to the rotatable shaft. The post insulators facilitate adjusting of the position of the slip ring relative to the rotatable shaft, e.g., to provide concentric positioning. The post insulators comprise an attachment/adjustment assembly ( ) for connecting to the slip ring. In one embodiment, the attachment/adjustment assembly comprises a spring plate ( ) which is adjustably biased to provide a preloading displacement that absorbs differential movement due to temperature changes of the slip ring an the rotatable shaft. In one example deployment, the current collector system is provided as part of a rotary transformer system ( ) which, e.g., transfers electrical power between a first electrical system (e.g., first electrical grid) and a second electrical system (e.g., second electrical grid).

Slip-ring mounting assembly for high-power rotary current collector system

An electrical current collector system ( ) comprises an electrically conductive slip ring ( ) mounted to a rotatable shaft ( ), as well as a fixed conducting ring assembly ( ) having slip ring-contacting members ( ) mounted thereon. The slip ring ( ) and fixed conducting ring assembly ( ) are mounted to have an annular gap ( ) formed therebetween. A slip ring support assembly ( ) comprising plural post insulators ( ) spaced radially about the rotatable shaft attaches the conductive slip ring to the rotatable shaft. The slip ring and fixed conducting ring assembly are at least partially enclosed in a compartment ( ), to which a source ( ) applies a cooling/cleaning fluid. In accordance with the structure and method of the invention, the source directs the fluid over at least some of the post insulators for cleaning of the post insulators. Then the fluid travels through the gap to perform at least one of cooling and cleaning of an interface of the slip ring and the slip ring-contacting members. The conductive ring channel then directs the fluid in at least a partially semicircular path to an exhaust duct ( ).

Cleaning/cooling of high-power rotary current collector system

A method and apparatus for detecting motor contamination utilizes zero-sequence currents in a sensing coil to detect contamination. The detector includes a current transformer comprised of a magnetic core and a sensing coil wound about the core. A processor processes a sub-trip level current from the sensing coil to detect contamination. Three contamination detection methods, which may be used separately or in desired combination, are based on current trends, current leakage, and current clustering. An alarm is triggered when predetermined alarm criteria have been met.

Motor winding contamination detector and detection

A sandwich type insulation for electrical machinery comprising a laminate of a polymeric material such as polyimide which contains particles of an inorganic corona resistant material, said polymeric material being bonded to mica paper consisting of mica, wherein said mica paper may be impregnated with polymeric resin containing particles of inorganic corona resistant material. The resultant insulation may be used as a tape or wrapper.

Sandwich insulation for increased corona resistance

A rotor for an induction motor of the squirrel cage type wherein the rotor bars are exposed to a resilient anti-sparking compound in the rotor slots of the machine. The rotor bars are provided with a longitudinal slot to permit the insertion of the anti-sparking compound after assembly of the squirrel cage rotor. Alternatively, the laminations may be shaped to produce a longitudinal groove in the rotor bar slot to permit the insertion of the anti-sparking compound in the groove so produced. Of course, both the rotor bar and the rotor slot may both be provided with complimentary slots adjacent one another in which the anti-sparking compound may be injected.

Spark suppression of induction type rotors of dynamoelectric machines

This invention relates to a rolling electrical contact assembly which is very similar to an anti-friction bearing. The contact has an inner and outer race made of a conductive material. A set of conductive rollers roll around in the space between the races. A cage (insulating) keeps the rollers in proper spaced relationship. The outer race is stationary and is composed of segments having V-shaped spaces between the segments and is connected to an electrical cable, and the inner race which rotates on a shaft is connected by a cable carried by the shaft to a suitable current destination. The segments of the outer race are spring loaded to improve the contact conductivity between the rollers and the inner and outer races.

Anti-friction rotating contact assembly

A circuit for monitoring the temperature of the contacts of an electrical switching device (such as a circuit breaker), comprises an electrical analogue circuit of the thermal characteristics of the switching device. The analogue circuit comprises electrical resistance and capacitance, interconnected so as to form an electrical model of the heat flow paths and capacitances respectively, in the switching device. The preferred embodiment also provides a temperature sensing device to introduce to the analogue circuit a voltage signal the magnitude of which is proportional to the exterior temperature of the switching device. The analogue circuit is connected in a series circuit relationship with a current controller. The current controller controls the amount of current flowing through the analogue circuit. The current controller is in turn controlled by a voltage control signal proportional to the amount of current being carried by the switching device. The current controller is operated in such a fashion that the current it lets flow through the analogue circuit is proportional to the square of the voltage control signal.

Overtemperature protective circuit for switching devices

In an electrical substation, the use of separate towers or poles to terminate overhead lines is obviated by using bus duct for this purpose. Isolated phase or metal-clad bus duct is erected to provide not only the electrically conductive path between the overhead lines and the associated electrical equipment, but also the mechanical strength necessary in order to eliminate the towers and poles of the prior art.

Growing community of inventors

Peterborough, Canada

Robert Henry Rehder