Optimal control processes in active distribution networks

In this chapter, we consider a centralized real-time control architecture for voltage regulation and lines congestion management in ADNs that is based on a linearized approach that links control variables (e.g., power injections and transformers tap positions) and controlled quantities (e.g., voltages and current flows) by means of sensitivity coefficients.We validate the proposed analytic method by making reference to typical IEEE 13- and 34-bus distribution test feeders. The numerical validation of the computation of the coefficients is performed using the IEEE 13-bus test feeder and it shows that the errors between the traditional approaches, i.e., based on the inverse of the Jacobian matrix, and the analytic method are extremely low (in the order of magnitude of 10−6 - 10−9). The IEEE 34-bus test feeder is used to show application examples related to a possible integration of the proposed method for the problem of optimal voltage control and lines congestion management in unbalanced distribution systems. The simulation results show that the proposed algorithm is able to improve the voltage and current profiles in the network, and also that when each of the three phases of the DERs can be controlled independently of the others, the resulting optimal voltage and current profiles are better than the ones corresponding to the balanced control of the three-phase output of the set points of the DERs.