We study a dual-port grid-forming (GFM) control for power systems containing
ac and dc transmission, converter-interfaced generation and energy storage, and
legacy generation. To operate such a system and provide standard services,
state-of-the-art control architectures i) require assigning grid-following
(GFL) and GFM controls to different converters, and ii) result in highly
complex system dynamics. In contrast, dual-port GFM control (i) subsumes
standard functions of GFM and GFL controls in a simple controller, ii) can be
applied to a wide range of emerging technologies independently of the network
configuration, and iii) significantly reduces system complexity. In this work,
we provide i) an end-to-end modeling framework that allows to model complex
topologies through composition of reduced-order device models, ii) an in-depth
discussion of universal dual-port GFM control for emerging power systems, and
iii) end-to-end stability conditions that cover a wide range of network
topologies, emerging technologies, and legacy technologies. Finally, we
validate our findings in a detailed case study