Square D Company

Philip J Hopkinson

Dilip R Purohit

Richard R Rettew

Gary D King

David L Swindler

Wesley W Schwartz

Scott F Lett

Vadim Raff

An electrical transformer is disclosed. The electrical transformer comprises a central axis, a first modular section, and a second modular section. The first modular section is positioned about the central axis and comprises a first support, a first winding of a conductive element, and a first insulating material. The first winding of a conductive element is located about the first support. The first insulating material covers a portion of the first modular section. The second modular section is axially aligned with the first modular section and electrically connected to the first modular section. The second modular section comprises a second support, a second winding of a conductive element, and a second insulating material. The second winding of a conductive element is located about the second support. The second insulating material covers a portion of the second modular section.

Transformer winding

A method and apparatus for detecting a partial discharge in a voltage transformer, the transformer having a first voltage winding and a second voltage winding. A grounded electrostatic shield being operably attached to the transformer, preferably between the windings. A radio frequency current transformer is operably connected to the electrostatic shield wherein the partial discharge occurring within the voltage transformer is detected.

Method and apparatus for detecting partial discharge in a voltage transformer

A transformer including a core having first and second portions, and first and second primary winding sections. The first primary winding section includes a plurality of winding layers (L,&minus;L,) about the first portion of the core, and the second primary winding section includes a plurality of winding layers (L,&minus;L,) about the second portion of the core. Corresponding winding layers of the first and second winding sections are separated by a distance (D,&minus;D,). The distance (D,&minus;D,) between the corresponding layers of first and second primary winding sections increases as the number of winding layers (L,&minus;L,) increases.

The present invention relates to a transformer having a conductive element spiraling along the length of an insulated wire of the coil. When formed into plurality of adjacent turns, the conductive element couples one of the plurality of turns with another of the plurality of turns. The conductive element increases the series capacitance of the transformer circuit. A resistive element may also spiral along the length of the insulated wire to couple one of the plurality of turns with another of the plurality of turns. The resistive element not only increases the series capacitance of the transformer, but also increases the series conductance of the transformer circuit. The increase in the series resistance increases the dampening of the switching resonance.

Winding transient suppression technique

The present invention relates to a transformer comprising a coil having an insulated wire formed into a plurality of turns defining a layer and a resistive element wrapped around the outer surface of the layer. The resistive element couples one of the plurality of turns with another of the plurality of turns. The resistive element not only increases the series capacitance of the transformer, but also increases the series conductance of the transformer circuit. The increase in the series resistance increases the dampening of the switching resonance.

High frequency snubber for transformers

This invention relates to a cooling system for a transformer. A winding defining a coil, including a duct having an open top and bottom, is sealed to a sleeve, thus forming a closed circulatory path. A fluid is retained and circulated within the circulatory path.

Transformer cooling method and apparatus therefor

An improved low voltage winding for dry insulated transformer has its windings resin encapsulated. The winding is constructed with flexible sheet conductors wound coincident with an insulating sheet material. Insulating spacers provide a means to form air channels in the windings during the coil forming process. A sealant is applied to openings at the lower ends and along vertical seams of the coil prior to the resin impregnation and encapsulation process. This will prevent drainage of the resin during a curing cycle. The result is a coil that exhibits high short circuit protection due to the tightly bond sheet conductors which will prevent movement of the conductors during short circuit conditions and also increases the radial compressive strength of the coil.

Strip wound induction coil with improved heat transfer and short circuit

A hybrid transformer core assembly having a first leg having a first end and a second end, a second leg having a first end and a second end, and opposing first and second yokes coupling the first and second legs to the first and second yokes to create a closed core. The first leg and second legs are made of a plurality of packets of laminations having a high grain orientation, and the first and second yokes are made of a plurality of packets of laminations having a lower grain orientation than the material of the first and second legs. Alternating laminations of the first and second legs are staggered to alternately extend beyond adjacent laminations of the respective leg at first and second ends thereof. A portion of the laminations of the first and second legs which extend beyond adjacent laminations of the first and second legs, respectively, overlaps portions of alternating laminations of the yokes and couples with notches of alternating laminations of the yokes. Additionally, a portion of the laminations of the first and second legs overlaps portions of alternating laminations of the yokes to similarly couples the legs with the yokes.

Growing community of inventors

Charlotte, NC, United States of America

Philip J Hopkinson