Abstract: Digital twin is the key technology of digitalization transformation in power equipment industry. In this paper, a general digital twin architecture of power equipment is proposed after analyzing current research status. Based on industrial development, four important technologies in simulation and modeling are defined, such as unified information modeling, multi-level simulation modeling, multi-parameter multi-physics inversion, and multi-dimensional complex information synthesis and visualization analysis. In addition, typical applications, current deficiencies, and future focus of this technology, in the aspect of intelligent design and manufacturing, dynamic management of supply chain, and operation and maintenance, are also discussed. Moreover, the prospects in the changes of the relevant industries brought by digital twin technology are presented, which can serve as a good reference for digitalization transformation of power equipment industry.