N-1-Secure Dispatch Strategies of Embedded HVDC Using Optimal Power Flow

With the ongoing changes in the European electrical energy systems, redispatch measures are more often required to maintain system security. The introduction of HVDC transmission can potentially reduce necessary redispatch not only by providing additional transmission capacity but also with its inherent controllability. This work analyzes the effect of HVDC dispatch in regard to preventive and curative redispatch measures using a security constrained optimal power flow calculation. For this, a mixed ac/dc benchmark network with predefined contingencies is examined with different redispatch options for pre- and post-contingency operation. Results show, that the required redispatch measures can be reduced significantly by an adaptation of HVDC set points and even further, when post-contingency redispatch measures could be applied.