A winding unit for connecting to a high-voltage grid or network includes a winding embedded in a solid insulating body and a first main connection terminal connected to a first winding end of the winding and disposed on a first support formed on the insulating body. A second main connection terminal is connected to a second winding end of the winding. The winding has partial windings and taps for adjusting the number of windings of the partial windings connected in series. Outgoing lines extending in the insulating body connect the taps to a tap connection terminal accessible from the outside. The tap connection terminals are formed on the support in order to encapsulate the higher voltage in a resin block over the entire periphery by using a shielding cage.

A transformer assembly for electric grids including: an electric transformer including a magnetic core, a first side including one or more first windings enchained with said magnetic core and adapted to be electrically connected to a first grid section and a second side including one or more second windings enchained with said magnetic core and adapted to be electrically connected to a second grid section; a tap changer operatively associated with said electric transformer to vary the number of turns enchained with said magnetic core for said first windings; a control unit to: acquire input data indicative of an electrical connectivity condition of said second grid section with said second windings; determine whether said transformer is in a load condition or in a no-load condition; and, in a no-load condition, command said tap changer to set a maximum available number of turns for said first windings.

An inductive power device with variable active winding size, comprises first circuitry, multiple winding segments and switching circuitry operable to connect selectable combinations of the winding segments serially to the first circuitry via taps. At least two of the winding segments are of unequal size, wherein said at least two winding segments are provided as sequential portions of a total winding magnetically coupled to an opposite winding, wherein the winding segments have uniform polarity with respect to said magnetic coupling. The switching circuitry comprises an arrangement of semiconductor switches which are operable to include or exclude each winding segment independently. In an embodiment, the arrangement of switches comprises at least one half-bridge structure.

A system includes conductive windings extending around a magnetic core and impedance-varying windings extending around the magnetic core. The impedance-varying windings include positive windings and negative windings. The conductive windings and the impedance-varying windings conduct electric current around the magnetic core. The system includes a first impedance tap changer that is electrically coupled with the positive windings of the impedance-varying windings and a second impedance tap changer electrically coupled with the negative windings of the impedance-varying windings. A controller controls the first impedance tap changer and the second impedance tap changer to change an impedance of the system by changing which portion of the positive windings and which portion of the negative windings are conductively coupled with the conductive windings, and which portion of the positive windings and which portion of the negative windings are disconnected from the conductive windings.

An on-load tap-changer uninterruptedly operates a diverter switch between different winding taps of a tap-changing transformer. The on-load tap-changer has an on-load tap-changer plate; a selector; and a diverter switch. The selector and the diverter switch are mounted on the on-load tap-changer plate.

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.

A space efficient planar transformer can include a coupled inductor circuit that can include a metallic core, a first planar winding comprising a conductive coil having an electrical path encircling a first post of the metallic core, and a second planar winding configured to magnetically couple with the first winding via the metallic core. The second planar winding can have multiple portions. A portion of the second winding can include a first sub-portion comprising a single U-shaped planar conductive trace wrapped about the first post and a second sub-portion comprising a single U-shaped planar conductive trace wrapped about the first post. A layout of the first sub-portion can be oriented opposite a layout of the second sub-portion.

An electromagnetic induction device includes: a main tank, a magnetic core arranged in the main tank, an On-Load Tap Changer, OLTC, comprising: an OLTC tank mounted to the main tank, a fine selector, a diverter switch, a change-over selector, and a customer interface; and a barrier separating the main tank from the OLTC tank, wherein the diverter switch and the change-over selector are arranged in the OLTC tank, and the fine selector and customer interface are arranged in the main tank, and wherein the barrier comprises a plurality of electrical connections configured to connect the diverter switch and the change-over selector to the fine selector.

The present disclosure provides an exemplary three-phase multi-tap balancing distribution transformer capable of operation with both balanced and unbalanced loads and that provides a wide range of incremental voltages to compensate for the varying voltage drops and imbalances as the attached conductor length increases and allows users the ability to incrementally and independently adjust the voltage specifically feeding a specific phase. Incremental adjustment is achieved via the transformer and without any fragile or other external devices or components between the power source and load-side equipment terminals. The transformer, through the use of at least one phase-specific tap-change switch is capable of directly controlling the secondary voltage of the applicable phase independently from the other phases and, thus, does not affect the voltage on the other phases.

Transformer assembly has an input terminal, principal housing with main chamber for high voltage coil(s) having plurality of taps, low voltage coil(s) and retaining oil. An auxiliary housing extends outwardly from principal housing and is fluidly connected to main chamber so that auxiliary housing contains oil. A potential transformer; load tap changer having a controller, a motor and a plurality of switches; electrical wiring connected to taps, switches within auxiliary housing chamber are submerged by oil within auxiliary chamber; load tap change controller can adjust taps while the switches and electrical connections are submerged in oil of auxiliary housing chamber. The upper level of oil in the main housing chamber is at a level equal to or above the switches of the load tap changer. The auxiliary housing has an access opening and cover. System apparatus with frames, having beams, lattices and cable guides for routing cables for assembly.