A Start-up and Recovery Method with LCC-HVDC Systems participation during AC/DC System Black-starts

With the increase in a number of online high-voltage direct current (HVDC) systems in China, a big question for their use as black-start and restoration of power system outages arises. Line-commutated converters (LCC)–HVDC systems can significantly reduce recovery time. The black-start-up and recovery conditions for LCC–HVDC systems and the connected AC systems are discussed in this study. The appropriate start-up and recovery modes are identified and the results of the control characteristics of LCC–HVDC systems are analysed in detail. The stability requirements of AC systems in terms of LCC–HVDC system effects are evaluated. Furthermore, the restoration using LCC–HVDC systems, including the priority sequence index of the multi-HVDC links and the optimisation model of the mentioned problem, is discussed in detail. Compared to the conventional black-start strategy, the applicability and effectiveness of the proposed method are illustrated using a part of the actual Guangzhou power system as a test system.