Some of the above-listed disadvantages can be eliminated with the use of new technologies. In particular, disadvantages such as a complete power fault of the HVDC transmission system during short-circuits inthe AC power system and reactive power consumption can be eliminated completely, or mostly, with the use of turn-off thyristors.Several research centers are working on improving high-capacity turn-off thyristors and also on new types of converter devices for high-capacity HVDC transmission.Finally, there are several new techniques for the perfection of grounding devices, providing for decreased electro-corrosion impacts and the formation of so-called “metal return”, which precludes the working current from flowing through the ground. Other techniques aimed at perfecting HVDC technology are also being developed (Koshcheev 2001).