Abstract: The present invention relates to a transformer being protected against direct current induced by geomagnetic flux changes, so called zero sequence current, whereby it comprises at least one compensation winding for direct current on the transformer core to compensate for undesired magnetization, by adding a current opposite to the direction of the magnetization caused by the zero sequence current carried by the alternating current to be transformed to reduce high magnetization saturation levels.

Abstract: The present invention relates to a method for protection of power transformers and other power system components, which are vulnerable to geomagnetically induced currents, which comprises feeding from an overhead line/s or cable conductor/s one or more DC-diverter consisting of primary diverter windings and compensation windings applied on a respective magnetic core leg, which diverter is connected to critical busses, and diverting “quasi” direct current flowing on the overhead lines or cable conductors as a result of the earth surface potential gradients caused by geomagnetically induced currents, as well as a DC diverter to carry out the method.

Abstract: The present invention relates to a transformer being protected against direct current induced by geomagnetic flux changes, so called zero sequence current, whereby it comprises at least one compensation winding for direct current on the transformer core to compensate for undesired magnetization, by adding a current opposite to the direction of the magnetization caused by the zero sequence current carried by the alternating current to be transformed to reduce high magnetization saturation levels.