Patent ID: 6411529
Filing Date: 2002-06-25
Classification: H02M

Abstract:
A plant for transmitting electric power comprising a first power semiconductor device having conducting and non-conducting states and being connected in series with a conductor and a second power semiconductor device having conducting and non-conducting states, connected in anti-parallel therewith and being able to assume the non-conducting state in which it blocks conduction of current therethrough when voltage is applied to the first power semiconductor device in a conducting direction thereof and being able to assume the conducting state in which it conducts current therethrough when voltage is applied over the first power semiconductor device in a direction opposite to the conducting direction, said first semiconducting device comprising a turn-off type power source and the second semiconducting device comprising a controllable device having a conducting direction opposite to that of said first power semiconductor device; a switch wherein the first power semiconductor device is operable to conduct current during normal function of the plant and operable to be turned off for fulfilling a dis-connector function when desired, said switch is arranged in a network for transmitting high voltage direct current (HVDC) for safety disconnection upon occurrence of a fault, the switch being arranged proximate to a converter associated with a first station for converting direct voltage into alternating voltage conversely comprising an arrangement adapted to control a change of state of the second power semiconductor device to the blocking state for preventing feeding of current towards the converter when desired, and at least one converter of a second state being connected in parallel with said proximate converter, said converters belonging to different stations of a multiple station system having direct voltage networks connected in a meshed fashion.