Patent ID: 8471416

Claim:
A method for creating working space within the right of way occupied by an existing three phase high voltage transmission line comprised of three phases, each phase comprised of one or more conductive cables, by removing one of the three phases from service and enabling the remaining two active phases to carry the power previously carried by three active phases, the method comprising: installing a temporary, transportable substation at each terminal of the transmission line, to provide for the control of the mode of power transmission over the transmission line, wherein the temporary, transportable substations are each electrically coupled to first and second transmission line phases, and serve to change the mode of transmission between the substations from three phase alternating current to two-pole direct current, wherein one substation comprises an ac-to-dc converter station and the other comprises a dc-to-ac converter station, thus allowing the first and second transmission line phases to transmit power while the third phase is removed, replaced, or grounded; removing the voltage applied to the third transmission line phase; and continuing to transmit power on the first and second transmission line phases, to allow work to be conducted on or proximate to the third transmission line phase while power is still carried along the right of way.