Abstract: A transformer installation including at least one non-liquid immersed transformer having a magnetic core including at least two core legs each having a winding axis. The transformer further includes at least two coil windings wound around at least one of the core legs of the magnetic core about the winding axis. The transformer installation further includes at least one coil cooling tube defining a coil cooling channel for guiding a dielectric cooling fluid. The at least one cooling tube is wound about at least one of the at least two coil windings. The transformer installation further includes at least one core cooling channel arranged within the core. The core cooling channel is configured to guide a dielectric cooling fluid through the core.

Abstract: A transformer is provided that includes an enclosure configured to house a core and a coil assembly mounted to the core. The enclosure includes a number of vertically extending sidewalls, at least one top wall connecting the sidewalls, and a bottom end opposite the at least one top wall. At least one of the sidewalls is joined to an access panel that is angled below the at least one top wall and extends between the bottom end of the enclosure and the vertically extending at least one sidewall. A first ventilation opening is provided in the angled access panel and a second ventilation opening is provided in the at least one sidewall adjacent to and/or in the top wall.

Abstract: A three-phase non-linear dry-type transformer has integral molds formed of a glass fiber-reinforced polymeric material. The low voltage coil is comprised of an inner low voltage mold formed around each of the at least three core legs, a low voltage conductor winding wound upon the inner low voltage mold and an outer low voltage mold formed around the low voltage winding. The high voltage coil is comprised of an inner high voltage mold disposed around the outer low voltage mold, a high voltage conductor winding wound upon the inner high voltage mold, and an outer high voltage mold formed around the high voltage conductor winding. An annular space between the inner and outer high voltage molds and the inner and outer low voltage molds is filled by an insulating polymeric material during a casting process. The molds are bonded to the coil windings by the insulating polymeric material and remain during the operation of the non-linear transformer as integral components of the non-linear transformer.

Abstract: A three-phase non-linear transformer is cooled by first (30) and second fans (40). The first fan (30) is attached to the first core clamps (12) of the transformer using a first mounting structure (15). The second fan (40) is attached to the second core clamps (24) of the transformer using a second mounting structure (17). The first fan is positioned first so that air is directed toward a central passage of the core. The second fan is positioned so that air is drawn through the central passage of the core. The first fan circulates air through a central passage in the transformer core and channels that exist between adjacent coil assemblies. The second fan draws air through the central passage and channels and further expels the air into the surrounding environment. The first and second fans are controlled by a control panel through which they are run automatically or manually.

Abstract: A composite electrical insulation material is comprised of first, second and third layers. The first and third layers are glass fiber mat and the second layer is a thin film material. The first and third layers are bonded to the second layer using a thin resin solution. The insulation is used in electrical machines such as transformers, generators, and motors. The insulation serves as a high/low barrier, high voltage conductor wrap, and low voltage sheet insulation in transformers. In generators and motors, the insulation serves as wrap for conductor windings and wedge insulation for stator and rotor assemblies.

Abstract: Tap covers and projections for an electrical device are provided. The tap projections have bosses or taps raised from a surface of the tap projection and encapsulated with a resin except for an outer surface of the bosses or taps. The tap projections may have a channel or recess between individual bosses or taps to prevent degradation of the insulation between the respective adjacent bosses or taps. When a tap cover is provided, it is pushed on or bolted to the tap projection. The tap cover may be provided for an individual tap or an entire tap projection and may be formed of a resin or an elastomeric material. The tap cover has a first generally planar surface and a second generally annular surface having a circumferentially-extending groove on an inside surface. The circumferentially-extending groove is located slightly beneath the second generally annular surface. The groove of the tap cover is designed to fully engage with a raised lip of a tap projection or individual tap of a transformer.

Abstract: A distribution transformer adapted for mounting to a utility pole. The distribution transformer includes a plurality of coil assemblies mounted to a ferromagnetic core. Each of the coil assemblies includes a low voltage coil and a high voltage coil. The low voltage coils are connected together and the high voltage coils are connected together. An encasement comprised of an insulating resin encapsulates the core and the coil assemblies. The encasement includes a substantially annular body and a pair of high voltage bushings extending outwardly from the body. Terminals extend from the high voltage bushings and are connected to the high voltage coils.