An electric transformer comprising a coil made of at least one winding, the winding being made of a wire comprising a first section, a second section and a middle section between the first and the second sections, the first section forming a first spiral around an axis (Z) and the second section forming a second spiral around the axis, the first and second spirals being located in two separate planes perpendicular to the axis, an inner end of the first spiral, respectively the second spiral, located near the axis being near the middle section of the winding and an outer end of the first spiral, respectively the second spiral, located away from the axis being near a free end of the winding, the first spiral and the second spiral turning around the axis in opposite directions.

An electric transformer comprising a primary coil, a secondary coil and a first magnetic circuit, the first magnetic circuit comprising at least a first limb and a second limb, the primary coil being wound around the first limb of the first magnetic circuit and the secondary coil being wound around the first limb or the second limb of the first magnetic circuit, wherein the electric transformer further comprises a second magnetic circuit acting as a component for setting a total impedance of the electric transformer at a predetermined value, the second magnetic circuit comprising at least a third limb, only one coil among the primary coil and the secondary coil being wound around the third limb of the second magnetic circuit, the second magnetic circuit being independent of the first magnetic circuit.

A transformer includes a primary winding, a secondary winding, a first core, and a second core. The primary winding and the secondary winding are inserted into the first core and the second core, and the first core and the second core are disposed to face each other. The first core includes one first core portion, and the second core includes a plurality of second core portions. The first core is a lower core, and the second core is an upper core. The first core and the second core are disposed to face each other with a gap interposed between the first core and the second core. The first core and the second core include a heat-resistant elastic body in the gap, and are disposed to face each other. Each of the second core portions is disposed with a heat-resistant elastic body interposed between the second core portions.

A transformer includes a closed loop core having a first leg and a second leg. The transformer also includes a first primary winding surrounding the first and second legs, a second primary winding surrounding the first and second legs, and first and second secondary windings surrounding the first and second legs, respectively, and disposed between the first and second primary windings. A first turn of the first and second secondary windings are disposed on a first interlayer winding layer, and other turns of the first and second secondary windings are disposed on a first layer that is further from the first primary winding than the first interlayer winding layer.

A coil component including a terminal for external connection to which a plurality of secondary-side winding wires are connected, and a gathering member that gathers vicinities of terminal ends of the plurality of winding wires.

An assembly for connection to a high-voltage system has multiple single-phase transformers each having a transformer tank which is filled with a fluid and in which a core with at least one winding is situated. At least some of the windings of the single-phase transformers are connected to one another, forming a neutral point. A short-circuit voltage curve or impedance of the assembly can be adapted to different requirements. The windings are each connected to the neutral point via a switchover unit and a choke winding. The choke winding has multiple tappings, and the switchover unit is configured to select the tapping via which the winding in question is connected to the neutral point.

An assembly for connection to a high-voltage system has multiple single-phase transformers each having a transformer tank which is filled with a fluid and in which a core with at least one winding is situated. At least some of the windings of the single-phase transformers are connected to one another, forming a neutral point. A short-circuit voltage curve or impedance of the assembly can be adapted to different requirements. The windings are each connected to the neutral point via a switchover unit and a choke winding. The choke winding has multiple tappings, and the switchover unit is configured to select the tapping via which the winding in question is connected to the neutral point.

An Fe-based amorphous alloy ribbon reduced in iron loss, less deformed, and highly productive in a condition of a magnetic flux density of 1.45 T is provided. One aspect of the present disclosure provides an Fe-based amorphous alloy ribbon having first and second surfaces, and is provided with continuous linear laser irradiation marks on at least the first surface. Each linear laser irradiation mark is formed along a direction orthogonal to a casting direction of the Fe-based amorphous alloy ribbon, and has unevenness on its surface. When the unevenness is evaluated in the casting direction, a height difference HL×width WA calculated from the height difference HL between a highest point and a lowest point in a thickness direction of the Fe-based amorphous alloy ribbon and the width WA which is a length of the linear irradiation mark on the first surface is 6.0 to 180 μm.sup.2.

The present disclosure provides a transformer including at least one magnetic core each having at least one window; one primary side winding passing through the at least one window, a wire forming the primary side winding being sequentially covered with a first solid insulating layer, a grounded shielding layer and a second solid insulating layer from inside to outside along a radial direction of the wire, the grounded shielding layer being connected to a reference ground; and at least one secondary side winding, each passing through the at least one window, the primary side winding having a first voltage with respect to the reference ground, the secondary side winding having a second voltage with respect to the reference ground, and the second voltage being greater than 50 times of the first voltage.

An assembly for connecting to a high-voltage grid includes a plurality of single-phase transformers, each of which has a transformer tank that is filled with a fluid and is equipped with a core with at least one coil. The coils of the single-phase transformers are at least partly connected together, thereby forming a neutral or star point. In order to permit the assembly to be quickly assembled in situ while at the same time providing a reliable current path for compensation and grounding currents, the coils are connected together by a neutral or star point conductor or rail in order to form the neutral or star point. The neutral or star point conductor or rail is retained in an insulated manner on the transformer tank.