  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.
