An Efficient Model of Hybrid AC/DC Grid Power Flow based on the Simplified VSC Station Model

Large-scale new energy grid connections have promoted the rapid development of hybrid AC/DC grid with voltage source converter based multi-terminal DC (VSC-MTDC) grid. It is of great significance to realize the fast calculation of large-scale hybrid AC/DC grid power flows. This paper proposed a simplified VSC station model (SVSCM) on the premise of negligible error, which considered the accurate VSC loss model, in accordance with the electrical parameter characteristics in the VSC station. This paper further proposed an AC/DC power flow model with the minimum set of state variables based on the SVSCM (PF-SVSCM), which reduced the number of power flow equations. Under the premise of meeting a certain error, PFSVSCM realized the fast calculation of hybrid AC/DC power flow. In addition, PF-SVSCM considered a variety of control methods to ensure the universality of the model. Finally, the viability of the PF-SVSCM was confirmed through power flow calculations on the IEEE14-bus AC grid with a 4-terminal VSC station.