Adaptive Parametric Impedance Model Order Reduction Method for Grid-tied Renewable Energy Dominated Microgrid

Inhalt:
The high-precision reduced order impedance model can significantly reduce the computation burden in the small-signal oscillatory instability detection process of grid-tied renewable energy dominated microgrids (REMGs). However, due to improper interpolation strategies, the existing model order reduction method cannot build the high-precision parametric reduced order impedance model (PROIM) for REMG. To fill these gaps, this paper proposes the adaptive parametric model order reduction method to build a high-precision PROIM for REMGs. In this method, the adaptive optimization of system parameters and frequency interpolation points is achieved by introducing the evaluation indexes including convergence error, cumulative error, and projection matrix rank. The error performance of the obtained PROIM by the proposed method and its efficiency in actual oscillatory stability analysis are validated by a small-scale REMG with 4 different converter-based renewable generators (CREGs) and a real-time simulation model using a large-scale REMG of 4.2 MW with 18 different CREGs.