Patent ID: 6067238
Filing Date: 2000-05-23
Classification: H02J,Y02E

Abstract:
A method for reconstruction of a plant for transmitting electric power, which comprises a direct voltage network for High Voltage Direct Current (HVDC) and two stations connected thereto with line commutated valves having thyristors as rectifying semiconductor components for transmitting electric power between the direct voltage network and alternating voltage networks connected to the respective station thereof, the reconstruction aiming at connecting such additional stations to the direct voltage network while enabling feeding of electric power in an optional direction in each of the stations with the respective valve either in a rectifying operation for feeding electric power from the alternating voltage network to the direct voltage transmission or with the valve in an inverter operation for feeding from the direct voltage network to the alternating voltage network, said method comprising the steps of replacing in one of said two stations the thyristors with bidirectionally controlled thyristors (BCT) with ability to conduct current therethrough in both directions and installing such thyristors as rectifying semiconductor components in the valves of each added station so as to enable a choice of power feeding direction from the direct voltage network to the respective alternating voltage network or from the respective alternating voltage network out on the direct voltage network in said one and each added station by controlling the current direction through the respective valve.