Patent ID: 11875963
Assignee: SIEMENS ENERGY GLOBAL GMBH & CO. KG
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 0:
1. A device for connection to a high-voltage grid carrying an AC voltage and having a plurality of phases, the device comprising:
at least one active part having at least one phase connection for connection to a phase of the high-voltage grid;
at least one step winding connected to said at least one phase connection and to said at least one active part, said at least one step winding having a plurality of taps;
tap changers each having a respective selector for each step winding for a current-free changeover from a current tap to a desired tap of said at least one step winding;
load changeover switches each connected in series downstream of a respective selector for switching a current from said current tap to said desired tap;
impedance units each disposed between a respective selector and a respective load changeover switch, said impedance units having an impedance to be changed between a relatively lower impedance and a relatively higher impedance;
said active part for each phase having at least one main winding with an end remote from said at least one phase connection, said end being connected to one of said step windings;
each of said selectors having a first selector contact part for connection to said current tap and a second selector contact part for connection to said desired tap;
each of said load changeover switches having a first load changeover switch contact galvanically connected to said second selector contact part, a first load changeover switch contact galvanically connected to said first selector contact part and a moving part making contact with said first load changeover switch contact in a first switch position of said tap changer and with said second load changeover switch contact of said load changeover switch in a second switch position; and
said impedance units including first and second components, said first component being connected to said second selector contact part of each selector and said first load changeover switch contact of each load changeover switch and said second component being connected to said first selector contact part of each selector and said second load changeover switch contact of each load changeover switch, for enabling a current flow through one or another of said first or second components depending on a switch position of said tap changer.