Analysis on the Mode and Operation Characteristics of DC Grid Connection of Distributed Generation in Energy Internet

Energy Internet is a hot spot of research and practice in the field of energy at home and abroad. DC power distribution technology has the characteristics of bidirectional controllable power flow, convenient access to distributed resources, improved power quality, transmission capacity and reliability of power supply, and reduced system loss, which has a wide application prospect in energy Internet. The safety and reliability of ubiquitous distributed generation (DG) and multi load access to DC distribution network is an important problem to be studied and solved in the planning and operation of energy Internet. In this paper, the different ways and operation characteristics of AC-DG and DC-DG connected to DC distribution network are analyzed, in which AC-DG is connected through voltage source inverter, and DC-DG is connected through full bridge DC / DC converter. Based on PSCAD / EMTDC, and taken Shenzhen flexible DC distribution network demonstration project as an example, the dynamic operation characteristics of DGs under different modes of connecting to the DC distribution network are analyzed and verified.