A study on the dynamic model of a three-phase grid-connected inverter and an innovative method for its verification

The ever-increasing use of renewable energy sources has underlined the role of power electronic converters as an interface between these resources and the power grid. One application of these converters is in three-phase inverters utilized in a solar power plant to inject active/reactive power to the grid. The dynamic model of power electronic converters is necessary for investigating the overall system stability and the design of the controller for the converters. Generally, the inverter dynamic model is needed to investigate the dynamic behavior of inverters in different applications. This paper is a study of the dynamical model of the grid-connected voltage source inverter, which is extracted by the state-space averaging (SSA) method. This model is verified by applying the values of the operating point to the inverter in Matlab® Simulink environment. To attain the steady-state operating point, the zero component of the duty ratio of the converter is required. To obtain this component, the matrix form of the converter's average equations is used. Overally, using the above methods provides a more efficient and clear understanding of the dynamic model of the converter.