Abstract: A gapped core leg for a shunt reactor, comprising magnetic core elements separated by spacers cast directly between the core elements. Accordingly, a rigid core leg construction is achieved.

Abstract: A device for controlling an electric field at a high voltage component includes an inner deflector electrically connected to live voltage component; a resistive layer adapted for field control, arranged along the high voltage component, and electrically connected to the live high voltage component and electrically connected to a grounded part, the resistive layer having a nonlinear current-voltage characteristics; an insulating layer extending but ending without reaching the end of the resistive layer; and a semi-conducting or conducting layer arranged on the insulating layer and extending towards the resistive layer and past the end of the insulating layer, thereby defining an outer triple point at the intersection of the resistive layer, the insulating layer, and the semi-conducting or conducting layer. The resistive layer has first, second, and third adjacent sections, wherein a portion of the first section extends below the inner deflector.

Abstract: A high voltage shielding device including a main body having an enclosing outer solid insulating wall, an outer electrode arranged on the solid insulating wall providing a first level of insulation to the outer electrode, and a first inner electrode which is uninsulated or has a coating providing a second level of insulation, which second level of insulation is lower than the first level of insulation. The first inner electrode is oriented relative the outer electrode in such a way that the first inner electrode mainly shields a component of an electric field which is perpendicular to a component of an electric field mainly shielded by the outer electrode.

Abstract: A direct current cable termination apparatus for terminating a high voltage direct current cable, the apparatus includes a current-carrying device comprising a terminal portion of the direct current cable, the cable includes an electrical conductor, a circumferential electrically insulating layer located outside of the electrical conductor, and a circumferential conductive shield located outside of the insulating layer and the electrical conductor. The apparatus includes a housing having an outer shell, and the current-carrying device is adapted to extend in the axial direction of the outer shell. Along at least a part of the axial extension of the current-carrying device the outer shell extends axially with a space between its inner periphery and the current-carrying device.

Abstract: A direct current cable termination apparatus for terminating a high voltage direct current cable, the apparatus includes a current-carrying device including a terminal portion of the direct current cable, the cable including an electrical conductor, a electrically insulating layer located outside of the electrical conductor, and a conductive shield located outside of the insulating layer and the electrical conductor; and a housing including a tubular outer shell with an inner periphery and formed by an electrically insulating and polymer-containing material. The current-carrying device is adapted to extend in the axial direction of the outer shell. Along at least a part of the axial extension of the current-carrying device the outer shell extends axially with a space between its inner periphery and the current-carrying device. The housing is adapted to separate the space from an atmosphere outside the outer shell, and the space is filled with an electrically insulating fluid.

Abstract: A device for controlling an electric field at a high voltage component includes an inner deflector electrically connected to live voltage component; a resistive layer adapted for field control, arranged along the high voltage component, and electrically connected to the live high voltage component and electrically connected to a grounded part, the resistive layer having a nonlinear current-voltage characteristics; an insulating layer extending but ending without reaching the end of the resistive layer; and a semi-conducting or conducting layer arranged on the insulating layer and extending towards the resistive layer and past the end of the insulating layer, thereby defining an outer triple point at the intersection of the resistive layer, the insulating layer, and the semi-conducting or conducting layer. The resistive layer has first, second, and third adjacent sections, wherein a portion of the first section extends below the inner deflector.

Abstract: A method and arrangement for pressing of windings assembled onto a transformer. The method includes applying pressing force on the windings, and controlling the pressing force on the windings during drying of transformer active part. Thus, before the drying process commences, the windings are assembled onto the transformer core and a pressing force is applied to the windings assembled onto a respective transformer core limb, wherein an individual pressing force is applied to the respective winding. This individual pressing force applied to the respective winding is then controlled during the process of drying the transformer active part. The windings will as a result advantageously be effectively compressed onto the core and stabilized.

Abstract: A direct current cable termination apparatus for terminating a high voltage direct current cable, the apparatus includes a current-carrying device including a terminal portion of the direct current cable, the cable at least including an electrical conductor, a electrically insulating layer located outside of the electrical conductor, and a conductive shield located outside of the insulating layer and the electrical conductor. The apparatus includes a housing including a tubular outer shell with an inner periphery, the outer shell defining a longitudinal axis and being formed by an electrically insulating and polymer-containing material. The current-carrying device extends in the axial direction of the outer shell. Along at least a part of the axial extension of the current-carrying device the outer shell extends axially with a space between its inner periphery and the current-carrying device. The housing is adapted to separate the space from an atmosphere outside the outer shell.

Abstract: A test body for use in determining moisture content in a laminated insulation of a power transformer by measuring a dielectric frequency response of the test body. The test body has a laminated structure of the same material as the laminated insulation, and has a shape and a size to obtain moisture content characteristics that resembles the moisture content characteristics of the laminated power transformer insulation. The test body further includes electrodes, which are embedded in the laminated structure.

Abstract: A direct current cable termination apparatus for terminating a high voltage direct current cable. The apparatus includes a current-carrying device including a terminal portion of the direct current cable, the cable including an electrical conductor, an electrically insulating layer located outside of the electrical conductor, and a conductive shield located outside of the insulating layer and the electrical conductor; and a housing including a tubular outer shell with an inner periphery and formed by an electrically insulating and polymer-containing material. The current-carrying device is adapted to extend in the axial direction of the outer shell. Along at least a part of the axial extension of the current-carrying device the outer shell extends axially with a space between its inner periphery and the current-carrying device.

Abstract: A high voltage shielding device including a main body having an enclosing outer solid insulating wall, an outer electrode arranged on the solid insulating wall providing a first level of insulation to the outer electrode, and a first inner electrode which is uninsulated or has a coating providing a second level of insulation, which second level of insulation is lower than the first level of insulation. The first inner electrode is oriented relative the outer electrode in such a way that the first inner electrode mainly shields a component of an electric field which is perpendicular to a component of an electric field mainly shielded by the outer electrode.

Abstract: A direct current cable termination apparatus for terminating a high voltage direct current cable, the apparatus includes a current-carrying device including a terminal portion of the direct current cable, the cable including an electrical conductor, a electrically insulating layer located outside of the electrical conductor, and a conductive shield located outside of the insulating layer and the electrical conductor; and a housing including a tubular outer shell with an inner periphery and formed by an electrically insulating and polymer-containing material. The current-carrying device is adapted to extend in the axial direction of the outer shell. Along at least a part of the axial extension of the current-carrying device the outer shell extends axially with a space between its inner periphery and the current-carrying device. The housing is adapted to separate the space from an atmosphere outside the outer shell, and the space is filled with an electrically insulating fluid.

Abstract: A direct current cable termination apparatus for terminating a high voltage direct current cable, the apparatus includes a current-carrying device including a terminal portion of the direct current cable, the cable at least including an electrical conductor, a electrically insulating layer located outside of the electrical conductor, and a conductive shield located outside of the insulating layer and the electrical conductor. The apparatus includes a housing including a tubular outer shell with an inner periphery, the outer shell defining a longitudinal axis and being formed by an electrically insulating and polymer-containing material. The current-carrying device extends in the axial direction of the outer shell. Along at least a part of the axial extension of the current-carrying device the outer shell extends axially with a space between its inner periphery and the current-carrying device. The housing is adapted to separate the space from an atmosphere outside the outer shell.

Abstract: A direct current cable termination apparatus for terminating a high voltage direct current cable. The apparatus includes a current-carrying device including a terminal portion of the direct current cable, the cable including an electrical conductor, an electrically insulating layer located outside of the electrical conductor, and a conductive shield located outside of the insulating layer and the electrical conductor; and a housing including a tubular outer shell with an inner periphery and formed by an electrically insulating and polymer-containing material. The current-carrying device is adapted to extend in the axial direction of the outer shell. Along at least a part of the axial extension of the current-carrying device the outer shell extends axially with a space between its inner periphery and the current-carrying device.

Abstract: A direct current cable termination apparatus for terminating a high voltage direct current cable, the apparatus includes a current-carrying device comprising a terminal portion of the direct current cable, the cable includes an electrical conductor, a circumferential electrically insulating layer located outside of the electrical conductor, and a circumferential conductive shield located outside of the insulating layer and the electrical conductor. The apparatus includes a housing having an outer shell, and the current-carrying device is adapted to extend in the axial direction of the outer shell. Along at least a part of the axial extension of the current-carrying device the outer shell extends axially with a space between its inner periphery and the current-carrying device.

Abstract: A gapped core leg for a shunt reactor, comprising magnetic core elements separated by spacers cast directly between the core elements. Accordingly, a rigid core leg construction is achieved.

Abstract: A method, device and computer program product for determining the change in insulating ability of the insulation provided between two objects of an inductively operating element, where at least one of the objects is a winding. The device includes an analyzing unit, which obtains a first frequency spectrum associated with a frequency response to a signal of varying frequency, where the signal of varying frequency can be applied to a first object of the inductively operating element and the frequency response is obtainable from a second object of the inductively operating element, compares the obtained first frequency spectrum with a second reference frequency spectrum, detects a peak in the obtained first frequency spectrum that does not appear in the second reference frequency spectrum, analyzes the shape of the detected peak, and determines the change in insulating ability based on the analyzed shape.

Abstract: A test body for use in determining moisture content in a laminated insulation of a power transformer by measuring a dielectric frequency response of the test body. The test body has a laminated structure of the same material as the laminated insulation, and has a shape and a size to obtain moisture content characteristics that resembles the moisture content characteristics of the laminated power transformer insulation. The test body further includes electrodes, which are embedded in the laminated structure.

Abstract: A method, device and computer program product for determining the change in insulating ability of the insulation provided between two objects of an inductively operating element, where at least one of the objects is a winding. The device includes an analyzing unit, which obtains a first frequency spectrum associated with a frequency response to a signal of varying frequency, where the signal of varying frequency can be applied to a first object of the inductively operating element and the frequency response is obtainable from a second object of the inductively operating element, compares the obtained first frequency spectrum with a second reference frequency spectrum, detects a peak in the obtained first frequency spectrum that does not appear in the second reference frequency spectrum, analyzes the shape of the detected peak, and determines the change in insulating ability based on the analyzed shape.

Abstract: A method, device and computer program product for determining the change in insulating ability of the insulation provided around a conductor of an inductively operating element, which conductor is wound a number of turns. The device includes a signal generating unit that applies a signal of varying frequency to the conductor and an analyzing unit, which receives a frequency response to the signal from the conductor, compares the received frequency response with a reference frequency response and determines the change in insulating ability based on the comparison.