Dynamics Analysis Using Koopman Mode Decomposition of a Microgrid Including Virtual Synchronous Generator-Based Inverters

In the field of microgrids (MGs), steady-state power imbalances and frequency/voltage fluctuations in transient state have been gaining prominence owing to advancing distributed energy resources (DERs) connected MGs via grid-connected inverters. Because a stable, safe supply demand must be maintained, accurate analyses system dynamics are crucial. However, natural frequency components present make complex. The nonlinearity confidentiality inverters also hinder controllability. MG considered this study consisted synchronous generator (the main source) multiple with storage batteries virtual (VSG) control. Although smart inverter controls such as VSG contribute stabilization, they induce nonlinearity. Therefore, Koopman mode decomposition (KMD) was utilized for consideration future method data-driven analysis measured frequencies voltages, response performed. operator is linear on an infinite dimensional space, whereas original nonlinear map finite space. other words, proposed can precisely analyze all system, which involve complex nonlinearities caused by VSGs.