Security co-planning of generation and transmission considering flexible facility and high-penetration renewable energy

With high-penetration renewable energy integrated, the absence of flexibility is endogenously appeared, which draws the importance of installing flexible devices. To improve the network flexibility and prevent stochastic contingencies, a novel security co-planning methodology of generation and transmission with multiple flexible devices is proposed in this paper. The flexible facility installation is composed of VSC-HVDC feeder construction and TCSC extension. The flexibility of transmission network is represented by load shedding and renewable curtailment. Compared with the previous research, the proposed novel model takes comprehensive consideration of both AC and DC losses, which is more suitable for the practical scenario. For the sake of contingency adaptability, N-1 stochastic contingency is taken into consideration by consecutive branch-breaking. Case studies are carried out on the modified Gaver 6-bus and IEEE 24-bus test systems, and the results show that the proposed model is able to enhance the flexibility, reduce the loss cost and guarantee the security of the power system.