Overloads Management in Active Radial Distribution Systems: an Optimization Approach Including Network Switching

This paper focuses on the real-time overloads management in active radial distribution systems that host a significant amount of distributed generators (DGs). 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. To mitigate the computational burden posed by modeling the switching actions as binary variables we build upon a very convenient existing optimization framework that, for a radial distribution grid, transforms precisely the original mixed integer nonlinear programming (MINLP) problem into a much simpler mixed integer quadratically constrained (MIQC) one. Although the approach focuses on overload removal in course of optimization it also pays attention not worsening other operational constraints such as voltage limits. We prove the interest and feasibility of our approach using a 33-bus benchmark distribution system as well as a 61-bus real-life distribution system model.