Overloads management in active radial distribution systems: An optimization approach including network switching

Abstract

This paper focuses on the overloads management in active radial distribution systems that host a significant amount of distributed generation (DG). In order to possibly reduce the amount of generation curtailed to remove congestion, and hence harvest as much renewable energy as possible, we propose a centralized optimization approach that includes the option to use remotely controlled grid switches and breakers so as to transfer distributed generation between feeders. As switching actions are modeled as binary variables, to mitigate the computational burden posed by the original mixed integer nonlinear programming (MINLP) problem we build upon a very convenient existing optimization framework that, for a radial distribution grid, transforms precisely the problem into a much simpler mixed integer quadratically constrained (MIQC) program. Although the approach focuses on overload removal in course of optimization it also inhibits violation of other operational constraints such as voltage limits. We prove the interest and feasibility of our approach using a snapshot of a 33-bus benchmark distribution system and of a 61-bus real-life distribution system model, whereas future work is planned to assess the benefits of the method using time-series.