APPARATUSES AND METHODS FOR DC VOLTAGE CONTROL

There is provided a method for synchronising DC voltage performed by a converter controller. The method includes receiving an indication that a synchronisation process, in which a first DC voltage controlled by the converter controller is synchronised with a second DC voltage at a DC grid, is to be initiated; in response to receiving the indication, gradually adjusting the first DC voltage up and/or down; and while gradually adjusting the first DC voltage up and/or down, determining that the synchronisation process has been successful based on a detected DC current or rate of change of DC current being greater than a predefined threshold.