Patent ID: 8811806

Claim:
A power supply arrangement for direct electrical heating of as pipeline system comprising: a three phase transformer adapted to support a single phase load connected between a first phase and a second phase of the transformer, said transformer comprising at least one first tap changer at a high voltage side of the transformer; a symmetrization unit comprising both (a) a first capacitor means and (b) at least one first additional capacitor in parallel with the first capacitor means connected between the first phase and a third phase of the transformer and an inductor means connected between the second phase and the third phase of said transformer; and a compensation unit comprising both (a) a second capacitor means and (b) at least one second additional capacitor in parallel with the second capacitor means connected between the first phase and the second phase of the transformer, and a control unit adapted to automatically control voltage levels of said first tap changer, capacitance of said first capacitor means and said second capacitor means and inductance of said inductor means, wherein automatically controlling the capacitance of said first capacitor means comprises switching the at least one first additional capacitors using at least one corresponding first vacuum contactor, and automatically controlling the capacitance of said second capacitor second comprises switching the at least one second additional capacitors using at least one corresponding second vacuum contactor.