Analytically Computation of Sensitivity Coefficients in Hybrid AC/DC Micro-Grid

Abstract: In this paper, we present a closed-form model for the analytical computation of the power flow sensitivity coefficients (SCs) for hybrid AC/DC networks. The SCs are defined as the partial derivates of the nodal voltages with respect to the active and reactive power injections. The proposed method is inspired by an existing SC computation process proposed for AC networks and here extended to include both the DC grid and the relevant AC/DC Interfacing Converters (ICs). The ICs can operate under different control modes i.e. voltage or power. Additionally, the model is able to compute the SCs for three-phase networks subjected to unbalanced loading conditions. The proposed method is numerically validated by means of a comparison with a detailed time-domain simulation model solved within the EMTP-RV simulation environment. Furthermore, we provide a formal proof regarding the uniqueness of the proposed SCs computational model for hybrid AC/DC networks.