Flyback-converter-based source identification for investigation of dynamic stability with constant power loads

Dynamic interaction between various sources and loads in power-converter-based DC systems has been an area of increasing interest and research for several decades. Stability of a DC distribution system at a particular interface may be analyzed by looking at the source and load impedances in frequency domain, for which appropriate models are required. Since most of the sources and loads are switching converters with significant discontinuities, these studies are typically conducted by using appropriate average and small-signal models. Having appropriate accurate models will make it possible to run simulations and analyze the system in frequency domain. In this paper, we conduct comprehensive system identification of a commercially available Flyback converter that is used as a source in 48/24 VDC telecom DC power systems. The derived detailed and average-value models are verified experimentally. The identified source model is used in the investigation of dynamic stability of the considered DC distribution system with constant power loads (CPLs).