Semi-explicit multilinear modeling of a PQ open-loop controlled PV inverter in αβ-frame

This paper introduces semi-explicit multilinear modeling to ac power systems, including voltage source converters. Firstly, the novel semi-explicit multilinear modeling class is explained. Then this class is applied to a small example of PV inverter connected to an infinite bus. Some part of the nonlinear current reference calculation is expressed as a multilinear algebraic constraint. The formulation of this multilinear algebraic constraint allowed modeling the whole nonlinear inverter as a semi-explicit multilinear model. The novel modeling approach is compared with common nonlinear time-based simulation in Simulink. The results show a good approximation of the nonlinear model by its semi-explicit multilinear model where the relative error is below 10-3%. This low error motivates the further usage of the semi-explicit multilinear modeling class for power system analysis.