Interfacing SFA- and GAM-type dynamic phasors for modeling of integrated AC-DC power systems

Abstract

This paper focuses on the modeling of integrated ac-dc backup and generation power systems, which has received increasing attention due to the emergence of microgrids and distributed generations. The conventional shifted-frequency analysis (SFA) type dynamic phasors (DPs) assume a bandpass spectrum of power system signals, and thus are only suitable to model system components wherein the 60Hz fundamental frequency is dominant. To account for high-order harmonics of interest in ac-dc systems, this paper considers another type of DPs based on the generalized averaging method (GAM), and proposes a possible interface between the SFA- and GAM-type DP models. Computer studies demonstrate that the proposed DP interface allows for accurate simulations of both fundamental frequency components and high-order harmonics in integrated ac-dc power systems, while providing significant numerical advantages over the conventional time-domain detailed models.