Abstract: A unique transformer includes a first yoke formed of laminations oriented parallel to a first plane; a second yoke formed of laminations oriented parallel to the first plane; and a center leg formed of laminations oriented parallel to a second plane oriented at a non-zero angle relative to the first plane. The center leg includes a first end. The first yoke and the second yoke are in contact with the center leg at the first end. The transformer includes a coil disposed about the center leg, and a butt joint between the center leg and at least one of the first yoke and the second yoke.

Abstract: A transformer is provided having a stacked core with a pair of outer legs extending between a pair of yokes. The core is arranged in a plurality of layers. Each of the layers includes a pair of yoke plates and a pair of outer leg plates. In an innermost layer, the width of each yoke plate is less than the width of each outer leg plate. In each of the layers, the inner points of the outer leg plates are substantially in contact with the yoke plates. The cross-section of the inner leg and the outer legs may be rectangular or cruciform.

Abstract: A three-phase dry distribution transformer adapted for mounting outdoors on a pad or to a utility pole. The distribution transformer includes one or more winding assemblies mounted to a ferromagnetic core. Each winding assembly includes a low voltage winding and a high voltage winding. In each winding assembly, an encasement comprised of an insulating resin encapsulates the low voltage and high voltage windings. The encasement includes a body and a pair of high voltage bushings and a pair of low voltage bushing.

Abstract: A unique transformer includes a first yoke formed of laminations oriented parallel to a first plane; a second yoke formed of laminations oriented parallel to the first plane; and a center leg formed of laminations oriented parallel to a second plane oriented at a non-zero angle relative to the first plane. The center leg includes a first end. The first yoke and the second yoke are in contact with the center leg at the first end. The transformer includes a coil disposed about the center leg, and a butt joint between the center leg and at least one of the first yoke and the second yoke.

Abstract: A transformer is provided having a stacked core with a pair of outer legs extending between a pair of yokes. The core is arranged in a plurality of layers. Each of the layers includes a pair of yoke plates and a pair of outer leg plates. In an inner-most layer, the width of each yoke plate is less than the width of each outer leg plate. In each of the layers, the inner points of the outer leg plates are substantially in contact with the yoke plates. The cross-section of the inner leg and the outer legs may be rectangular or cruciform.

Abstract: A distribution transformer having a coil assembly mounted to a ferromagnetic core. The coil assembly includes a resin-encapsulated low voltage coil mounted to the core, a resin-encapsulated first high voltage coil disposed around the low voltage coil, and a resin encapsulated second high voltage coil disposed around the first high voltage coil. The first high voltage coil is separated from the low voltage coil by an annular first space, and the second high voltage coil is separated from the first high voltage coil by an annular second space. The low voltage coil and the first and second high voltage coils are arranged concentrically. The low voltage coil and the first and second high voltage coils have different axial lengths.

Abstract: A coil for a transformer includes first and second coil segments with each coil segment being defined by successive layers of wound conductor sheeting. The coil segments are electrically connected together and are adjacent, defining a space there-between. A plurality of cooling duct pairs are disposed between certain of the layers in each of the first and second coil segments such that, for each cooling duct pair, an end of a cooling duct disposed in the first coil segment is adjacent to an end of a cooling duct disposed in the second coil segment, with the ends being disposed in the space. A connector connects the adjacent ends of each pair of cooling ducts.

Abstract: A coil for a transformer includes first and second coil segments with each coil segment being defined by successive layers of wound conductor sheeting. The coil segments are electrically connected together and are adjacent, defining a space there-between. A plurality of cooling duct pairs are disposed between certain of the layers in each of the first and second coil segments such that, for each cooling duct pair, an end of a cooling duct disposed in the first coil segment is adjacent to an end of a cooling duct disposed in the second coil segment, with the ends being disposed in the space. A connector connects the adjacent ends of each pair of cooling ducts.

Abstract: A plug for ease of alignment of a temperature probe or sensor inside a duct of a transformer winding is provided. The plug is shaped for secure placement into a duct or passage of a transformer winding without requiring any adhering material. The insertion of the plug into the duct or passage brings the temperature probe into contact with the desired point along the transformer winding being thermally monitored.

Abstract: Method of manufacturing a dry-type open wound transformer having disc windings is provided. The transformer has one or more high voltage windings, each of which includes a plurality serially connected discs. Each disc has two or more sections, wherein the sections are separated from each other by spaces arranged in a circumferential configuration.

Abstract: A coil for a transformer includes first and second coil segments with each coil segment being defined by successive layers of wound conductor sheeting. The coil segments are electrically connected together and are adjacent, defining a space therebetween. A plurality of cooling duct pairs are disposed between certain of the layers in each of the first and second coil segments such that, for each cooling duct pair, an end of a cooling duct disposed in the first coil segment is adjacent to an end of a cooling duct disposed in the second coil segment, with the ends being disposed in the space. A connector connects the adjacent ends of each pair of cooling ducts.

Abstract: A plug for ease of alignment of a temperature probe or sensor inside a duct of a transformer winding is provided. The plug is shaped for secure placement into a duct or passage of a transformer winding without requiring any adhering material. The insertion of the plug into the duct or passage brings the temperature probe into contact with the desired point along the transformer winding being thermally monitored.

Abstract: A transformer is provided having a stacked core with a pair of outer legs extending between a pair of yokes. The core is arranged in a plurality of layers. Each of the layers includes a pair of yoke plates and a pair of outer leg plates. In an inner-most layer, the width of each yoke plate is less than the width of each outer leg plate. In each of the layers, the inner points of the outer leg plates are substantially in contact with the yoke plates. The cross-section of the inner leg and the outer legs may be rectangular or cruciform.

Abstract: A three-phase dry distribution transformer adapted for mounting outdoors on a pad or to a utility pole. The distribution transformer includes one or more winding assemblies mounted to a ferromagnetic core. Each winding assembly includes a low voltage winding and a high voltage winding. In each winding assembly, an encasement comprised of an insulating resin encapsulates the low voltage and high voltage windings. The encasement includes a body and a pair of high voltage bushings and a pair of low voltage bushing.

Abstract: A method of forming a transformer coil, wherein first and second fibrous layers are provided. Each of the first and second fibrous layers includes a fabric formed from a plurality of interconnected fibers and a plurality of spacers affixed to the fabric and protruding therefrom. A conductor layer is disposed over the first fibrous layer such that a first side of the conductor layer contacts the spacers of the first fibrous layer. The second fibrous layer is disposed over the conductor layer such that a second side of the conductor layer contacts the spacers of the second fibrous layer. A resin is applied so as to cover the conductor layer and the first and second fibrous layers.

Abstract: A method of manufacturing a transformer is provided. The method includes forming a disc-wound coil by forming a first conductor layer, a second conductor layer and a layer of cooling ducts between the first and second conductor layers. The first and second conductor layers each have a plurality of disc windings arranged in an axial direction of the disc-wound coil. Each of the disc windings includes a conductor wound into a plurality of concentric turns.

Abstract: The present invention is directed to a method of forming a transformer having a stacked core, which includes upper and lower yokes and first and second outer legs. The core also includes one or more inner legs. Each of the upper and lower yokes is formed from a stack of plates and has a rectangular cross-section. Each inner leg is formed from a stack of plates and has a cruciform cross-section. Each of the first and second outer legs is formed from a stack of plates and may have a cruciform cross-section.

Abstract: The present invention is directed to a method of making a transformer having a stacked core, which includes top and bottom yokes and first and second outer legs. The core also includes an inner leg that is formed from a pair of stacked plates, which abut each along a seam that extends in the longitudinal direction of the inner leg. Each of the upper and lower yokes may be formed from a single stack of plates, or a plurality of stacks of plates. Each of the inner and outer legs may also be formed from a single stack of plates, or a plurality of stacks of plates. The cross-section of the core may be rectangular or cruciform.

Abstract: A distribution transformer having a coil assembly mounted to a ferromagnetic core. The coil assembly includes a resin-encapsulated low voltage coil mounted to the core, a resin-encapsulated first high voltage coil disposed around the low voltage coil, and a resin encapsulated second high voltage coil disposed around the first high voltage coil. The first high voltage coil is separated from the low voltage coil by an annular first space, and the second high voltage coil is separated from the first high voltage coil by an annular second space. The low voltage coil and the first and second high voltage coils are arranged concentrically. The low voltage coil and the first and second high voltage coils have different axial lengths.

Abstract: A transformer and a method of manufacturing the same are provided. The transformer includes a coil assembly mounted to a leg of a core. The coil assembly includes a low voltage coil and an insulation spool disposed over the low voltage coil. The insulation spool is composed of an insulating material and includes a plurality of guide strips defining a plurality of series of aligned notches. A high voltage coil is mounted to the insulation spool and includes a plurality of disc windings disposed in the series of aligned notches, respectively. Each of the disc windings comprises alternating concentric conductor layers and insulating layers. The conductor layers each have a width to thickness ratio of greater than 20:1.