Robust Optimization Model of AC/DC Hybrid Distribution Network Considering Renewable Energy Uncertainty

The rapid growth of renewable energy integration and power load exacerbates the uncertainty of power flow, thereby threatening the security of distribution network, and causing difficult regulation. The increase in DC application makes rapid development of AC/DC power distribution network, which operates with preferable flexibility. Accordingly, this study proposes a robust optimization model based on the relaxation evolution algorithm. Firstly, the formulations of AC/DC distribution network model, which is in terms of second-order cone programming, are derived. Accordingly, a robust reactive power optimization model is established with the objective function for minimizing the power loss and voltage offset of AC/DC distribution network. Furthermore, a co-evolution algorithm based on the relaxation method is proposed to solve this model. Case studies based on the improved IEEE33 bus system were conducted in simulation. The robust optimization model is demonstrated to effectively locating and treating the worst case of renewable energy operation.