Research on Security Region of AC/DC Hybrid Active Distribution Network

Abstract

With the development of new energy, the AC power distribution system and the DC power distribution system are increasingly closely connected, which increases the flexibility of the system while also increasing the operational risk. In order to quickly evaluate the security of AC and DC distribution networks, steady-state safety region based on convex envelope generation is proposed. First, use a nonlinear model to obtain a set of uniformly distributed points on the boundary of the system security domain, and use the convex hull method to make the security region. Secondly, use a set of nonlinear optimization models to calculate the safe distance of the operating point, which is used to evaluate the current operating point Safety margin index, and proposed a heuristic-based method to obtain the best safe operating point, and provide more comprehensive safety information for the safe operation of the system. Finally, the feasibility of the proposed model and scheme is verified by an AC-DC hybrid active power distribution system based on the reform of the IEEE33-bus system.