Abstract: With rapid development of renewable energy and acceleration of construction of renewable-dominated new-type power systems, dynamic characteristics and synchronous stability of modern power systems become ever more complicated． This review will briefly introduce the development of traditional power systems and research status of renewable-dominated new-type power systems． The holism and reductionism are combined; three typical renewable energy equipment (nodes) including permanent magnetic synchronous generator, double-fed induction generator, and photovoltaic and AC transmission line (network) models are established within three timescales (including AC current control, DC-link voltage control, and electromechanical timescales) according to multi-timescale characteristics of new-type power systems． Machine-network interface relationship between nodes and network is uncovered． The dynamic model framework of new-type power systems is established． Finally, synchronous stability mechanism of new-type power systems is revealed． This work helps to understand dynamics of renewable-dominated new-type power systems and promote interdisciplinary collaborative research among electrical engineering, complex systems and statistical physics on these fundamental problems．