High-voltage direct current transmission installation having a high voltage regulation capability

摘要

An installation for transmission of electric power by means of high-voltage direct current has two converters (SRI, SRII), each of which is connected to an alternating-voltage network (NI, NII) and which are connected to each other through a dc connection (L). One converter (SRI) is controlled as a rectifier and another converter (SRII) is controlled as an inverter. One converter (SRI) is current-controlling and another converter (SRII) is voltage-controlling. The installation has means (VARCrect) adapted, at such a change of the control angle ( alpha rect) of the current-controlling converter (SRI) that the angle reaches a limit of a predetermined interval ( alpha max nom rect- alpha min nom rect) to control, by means of the voltage-controlling converter (SRII), the direct voltage (Ud) of the transmission in such a way that said change is limited.