Abstract: A wrapped stator coil for use in a generator is provided comprising: an electrical conductor coil; an insulating layer structure disposed about the electrical conductor coil; an interwoven layer structure disposed about the insulating layer structure and comprising insulating material and a first conductive material; and a conductive layer structure disposed about the interwoven layer structure and comprising a second conductive material.

Abstract: A wrapped stator coil for use in a generator is provided comprising: an electrical conductor coil; an insulating layer structure disposed about the electrical conductor coil; an interwoven layer structure disposed about the insulating layer structure and comprising insulating material and a first conductive material; and a conductive layer structure disposed about the interwoven layer structure and comprising a second conductive material.

Abstract: An insulated stator coil (16) is provided comprising a plurality of coil strands (18) having a top surface (24) and a bottom surface (26). A filler material (30) is disposed on the top surface (24) and the bottom surface (26) of the plurality of coil strands (18) to smooth discontinuities at the top and bottom surfaces (24, 26). A conductive cap (32, 34) disposed over each of the top and bottom surfaces (24, 26) of the plurality of coil strands (18). A conductive strip (46) is disposed between the filler material (30) and each respective conductive cap (32, 34). The conductive strip (46) is effective to lower a resistivity of the conductive caps (32, 34) such that partial discharges do not occur in the insulated stator coil (16).

Abstract: An insulated stator coil (16) is provided comprising a plurality of coil strands (18) having a top surface (24) and a bottom surface (26). A filler material (30) is disposed on the top surface (24) and the bottom surface (26) of the plurality of coil strands (18) to smooth discontinuities at the top and bottom surfaces (24, 26). A conductive cap (32, 34) disposed over each of the top and bottom surfaces (24, 26) of the plurality of coil strands (18). A conductive strip (46) is disposed between the filler material (30) and each respective conductive cap (32, 34). The conductive strip (46) is effective to lower a resistivity of the conductive caps (32, 34) such that partial discharges do not occur in the insulated stator coil (16).

Abstract: A wrapped stator coil for use in a generator. The wrapped stator coil includes an electrical conductor bar, a laminate tape structure, and a conductive structure. The laminate tape structure is disposed about the electrical conductor bar and includes an insulative first layer adjacent the conductor bar and a conductive second layer bonded to the first layer. The conductive structure includes a first end portion, an intermediate portion and a second end portion. The first end portion is in contact with the electrical conductor bar. The intermediate portion is in contact with the conductive second layer and is not in contact with the electrical conductor bar. The insulating layer is disposed about the conductive structure and the laminate tape.

Abstract: A voltage grading structure (40) as may be used in the stator coils of an electromotive machine is provided. A filler material (44) may be disposed on a top surface and a bottom surface of a stack of coil strands (22). The voltage grading structure may include an electrical isolation layer (46) on the filler material and may further include an electrically conductive layer (48) on the electrical isolation layer. An electrically conductive bar (50) is positioned on the electrically conductive layer. The conductive bar is electrically connected to at least one of the coil strands (22) to shunt a capacitance effect between the conductive layer and the stack of coil strands and force the conductive layer to be substantially at a common voltage level relative to the stack of coil strands and thereby avoid an overvoltage condition.

Abstract: A voltage grading structure (40) as may be used in the stator coils of an electromotive machine is provided. A filler material (44) may be disposed on a top surface and a bottom surface of a stack of coil strands (22). The voltage grading structure may include an electrical isolation layer (46) on the filler material and may further include an electrically conductive layer (48) on the electrical isolation layer. An electrically conductive bar (50) is positioned on the electrically conductive layer. The conductive bar is electrically connected to at least one of the coil strands (22) to shunt a capacitance effect between the conductive layer and the stack of coil strands and force the conductive layer to be substantially at a common voltage level relative to the stack of coil strands and thereby avoid an overvoltage condition.

Abstract: A wrapped stator coil for use in a generator. The wrapped stator coil includes an electrical conductor bar, a laminate tape structure, and a conductive structure. The laminate tape structure is disposed about the electrical conductor bar and includes an insulative first layer adjacent the conductor bar and a conductive second layer bonded to the first layer. The conductive structure includes a first end portion, an intermediate portion and a second end portion. The first end portion is in contact with the electrical conductor bar. The intermediate portion is in contact with the conductive second layer and is not in contact with the electrical conductor bar. The insulating layer is disposed about the conductive structure and the laminate tape.

Abstract: A mechanical interface for relieving stress between an outer layer and an inner insulating layer in a layered insulating tape structure surrounding an electrical conductor. The interface tape includes a porous non-woven carrier having opposing sides including a release region located at a first side and a non-release region located at an opposite second side. The release region is treated with a release material for substantially inhibiting adhesion between the first side and an adjacent outer surface. The non-release region is untreated by the release material for substantially facilitating adhesion between the second side and an adjacent inner surface.

Abstract: A conformable layer (14) for inhibiting electrical discharge between vent tubes (16) and strands (12) in an inner-cooled coil (5). The conformable layer comprises a resistive inner core (24) and a conductive strip (20) wrapped in a conductive outer wrap (26). The conductive strip (20) is electrically connected to the strands (12) at one end of the coil (5) and left to electrically float at the other end. In this configuration, the conformable layer (14) reduces voltage buildup between the vent tubes (16) and the strands (12) to help prevent electrical damage to the coil (5).

Abstract: A conformable layer (14) for inhibiting electrical discharge between vent tubes (16) and strands (12) in an inner-cooled coil (5). The conformable layer comprises a resistive inner core (24) and a conductive strip (20) wrapped in a conductive outer wrap (26). The conductive strip (20) is electrically connected to the strands (12) at one end of the coil (5) and left to electrically float at the other end. In this configuration, the conformable layer (14) reduces voltage buildup between the vent tubes (16) and the strands (12) to help prevent electrical damage to the coil (5).

Abstract: High voltage coils (40) having an insulated coil surface that includes a composite tape (32) bonded to a secondary conductive layer (34) in a half lap manner. The composite layer comprising a glass conductive tape bonded to a layer of mica paper tape in an edge lap manner.

Abstract: A conformable layer (14) for inhibiting electrical discharge between vent tubes (16) and strands (12) in an inner-cooled coil (5). The conformable layer comprises a resistive inner core (24) and a conductive strip (20) wrapped in a conductive outer wrap (26). The conductive strip (20) is electrically connected to the strands (12) at one end of the coil (5) and left to electrically float at the other end. In this configuration, the conformable layer (14) reduces voltage buildup between the vent tubes (16) and the strands (12) to help prevent electrical damage to the coil (5).

Abstract: A support structure (20) is provided for supporting and spacing apart high-voltage electrical conductors (12) in an electric machine. An exemplary support structure (20) includes an improved spacer block (32,33) that is configured to reduce electrical flashover, in the form of creep, between adjacent high voltage conductors, without necessarily increasing the width of the spacer block. The improved spacer block (32,33) includes a main body (33) and a protruding portion (32), which elongates the creepage path (30) between adjacent high-voltage conductors to greater than the width of the spacer block (32,33).

Abstract: A method for producing an electrically conductive filler by placing a web of core material onto an interior surface of a web of conductive layer material. The webs of core material and conductive layer material are directed through a forming station for folding the conductive layer around the core. The filler having a substantially non-conductive core and a conductive layer. The conductive layer is wrapped around the core to form a closed loop thereby establishing conductivity from a bottom of the filler to a top of the filler by paths on each of two sides of the filler.

Abstract: An electrical isolation layer capable of inhibiting, if not preventing, a first conductive material from electrically passing or bleeding into a second conductive material and thereby causing a high resistance connection among the conductive materials is provided. The isolation layer has particular application when arranged between a conductive roebel filler and conductive strands sheathed by a porous insulator carrying a high voltage within a stator of a dynamoelectric machine used in a power generation plant.

Abstract: A high-voltage winding is described for use in a dynamoelectric machine. The high-voltage winding includes an electrical conductor (12), an insulator (14) surrounding the electrical conductor, and an electrically conductive layer (16) surrounding the insulator. The insulator (14) may include a tape (18) arranged to define a wrapped layer. A double-sided tape may be provided that includes a flexible tape substrate (20) with an inner major surface (22) adjacent the conductor (12) and an outer major surface (24) opposite the inner major surface. An inner silicate layer (26) may be secured to the inner major surface and an outer silicate layer (28) to the outer major surface. A single-sided tape may also be provided between the conductors and double-sided tape.

Abstract: An insulation insert (40) is provided for preventing electrical shorts and/or arcing between adjacent strands in a stator coil. The insulation insert includes a thin base (42) of substantially uniform cross section and a lead-in nose (43) formed in the thin base (42) for guiding the insulation insert (40) into a position between adjacent strands. The insulation insert (40) includes two substantially vertical cuts (45) in the thin base (42) above the lead-in nose (43), which delineate a center section (44) flanked by two ear portions (46). A head (54) and two wings (52) are formed in the insulation insert by folding the ear portions (46) along substantially horizontal creases (47).

Abstract: A high-voltage winding is described for use in a dynamoelectric machine. The high-voltage winding includes an electrical conductor (12), an insulator (14) surrounding the electrical conductor, and an electrically conductive layer (16) surrounding the insulator. The insulator (14) may include a tape (18) arranged to define a wrapped layer. A double-sided tape may be provided that includes a flexible tape substrate (20) with an inner major surface (22) adjacent the conductor (12) and an outer major surface (24) opposite the inner major surface. An inner silicate layer (26) may be secured to the inner major surface and an outer silicate layer (28) to the outer major surface. A single-sided tape may also be provided between the conductors and double-sided tape.

Abstract: An insulation insert (40) is provided for preventing electrical shorts and/or arcing between adjacent strands in a stator coil. The insulation insert includes a thin base (42) of substantially uniform cross section and a lead-in nose (43) formed in the thin base (42) for guiding the insulation insert (40) into a position between adjacent strands. The insulation insert (40) includes two substantially vertical cuts (45) in the thin base (42) above the lead-in nose (43), which delineate a center section (44) flanked by two ear portions (46). A head (54) and two wings (52) are formed in the insulation insert by folding the ear portions (46) along substantially horizontal creases (47).