Abstract: 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.

Abstract: 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.

Abstract: An electrical current collector system comprising 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: An electrical current collector system (20) comprises a rotatable shaft (28) having at least one and preferably plural electrically conductive slip rings (27) mounted thereon. For each phase, a slip ring is paired with a fixed conducting ring assembly (44). 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 (240) or rollers (404). The fixed conducting ring assembly comprises a first conducting plate (200T) and a second conducting plate (200B) positioned parallel to one another to form a conductive ring channel (220) therebetween. The slip ring-contacting members (240, 404) are mounted in the conductive ring channel. An at least partially transparent wall (200W) 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.

Abstract: An electrical current collector system includes a rotatable shaft (28); an electrically conductive slip ring (27); and a slip ring support assembly (42). The slip ring support assembly (42) comprises plural post insulators (102) 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 (106) for connecting to the slip ring. In one embodiment, the attachment/adjustment assembly comprises a spring plate (134) 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 (20) which, e.g.

Abstract: An electrical current collector system (20) comprises an electrically conductive slip ring (27) mounted to a rotatable shaft (28), as well as a fixed conducting ring assembly (44) having slip ring-contacting members (240, 404) mounted thereon. The slip ring (27) and fixed conducting ring assembly (44) are mounted to have an annular gap (48) formed therebetween. A slip ring support assembly (42) comprising plural post insulators (102) 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 (57), to which a source (302) 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.

Abstract: An electrical current collector system includes a rotatable shaft (28); an electrically conductive slip ring (27); and a slip ring support assembly (42). The slip ring support assembly (42) comprises plural post insulators (102) 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 (106) for connecting to the slip ring. In one embodiment, the attachment/adjustment assembly comprises a spring plate (134) 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 (20) which, e.g.

Abstract: An electrical current collector system (20) comprises an electrically conductive slip ring (27) mounted to a rotatable shaft (28), as well as a fixed conducting ring assembly (44) having slip ring-contacting members (240, 404) mounted thereon. The slip ring (27) and fixed conducting ring assembly (44) are mounted to have an annular gap (48) formed therebetween. A slip ring support assembly (42) comprising plural post insulators (102) 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 (57), to which a source (302) 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.