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.

Disclosed is a phase shift transformer for supplying voltage to a plurality of unit power cells in a medium voltage inverter system. The phase shift transformer according to the present invention comprises a first bushing arranged by the side of a tank and connected to a first winding to apply high voltage and a plurality of second bushings arranged on the top of a cover and connected to each of a plurality of second windings to output low voltage, wherein three outputs of the plurality of second bushings can be applied to unit power cells.

Disclosed is a phase shift transformer for supplying voltage to a plurality of unit power cells in a medium voltage inverter system. The phase shift transformer according to the present invention comprises a first bushing arranged by the side of a tank and connected to a first winding to apply high voltage and a plurality of second bushings arranged on the top of a cover and connected to each of a plurality of second windings to output low voltage, wherein three outputs of the plurality of second bushings can be applied to unit power cells.

An on-load tap changer has a switching tube, an oil suction pipe arranged centrally and coaxially along an axis inside the switching tube, and a kerosene drain screw so mounted in a base of the on-load tap changer that it is coaxial with an axis of the oil suction pipe, with the axis of the switching tube, and with an axis of the on-load tap changer. A bearing ring is so acted on by a resilient element at one side and radially with respect to the axis of the on-load tap changer that the switching tube and the oil suction pipe both mechanically positively cooperate with the bearing ring and are centered about the axis of the on-load tap changer.

A vacuum interrupter for an on-load tap changer comprising a cylindrical housing arranged on an axis including a wall enclosing a hermetically sealed inner volume and a ceramic bottom part extending perpendicularly to the axis, the wall comprising a first optical interface between the inner volume and an outer environment, the first optical interface being configured to be transparent to at least one optical wavelength, the inner volume comprising an optical guide open to an environment of the inner volume, a switch coaxially arranged with the housing on the axis within the inner volume of the housing, the vacuum interrupter further comprising a shield element coaxially arranged with the switch, characterised in that the optical guide is arranged recessed in relation to an inner surface of the ceramic bottom part of the wall and in that the shield element is arranged between the switch and the optical guide.