Optimal Corrective Control for Bipolar Multi-terminal HVDC Grid

An outage of DC transmission lines or converters occurs in bipolar multi-terminal HVDC grid (MTDC) may result in security violation. Corrective control strategies are therefore needed to ensure the operational security of the system. For MTDC grid following N-1 contingencies, a power shift-based optimal corrective control method is presented in this paper. Certain power are shifted from the faulty pole to the normal pole or among different converter stations within a pole, so that the amount of renewable energy accommodation of the MTDC is maximized. The method is intensively studied on a modified New England 10-machine 39-bus test system with inclusion of a four-terminal bipolar DC grid.