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

TL;DR

This paper introduces a closed-form analytical model for computing power flow sensitivity coefficients in hybrid AC/DC micro-grids, including unbalanced three-phase conditions and various converter control modes.

Contribution

It extends existing AC sensitivity computation methods to hybrid AC/DC networks with formal proof of model uniqueness and validation against detailed simulations.

Findings

The model accurately computes sensitivity coefficients for hybrid networks.

Validation shows close agreement with EMTP-RV simulations.

The approach handles unbalanced three-phase conditions.

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.