Control of a multi-terminal HVDC system for the exchange of primary reserve power across AC grids

• Applicant: Professor Dr.-Ing. Bernd Orlik
• Subject Area: Electrical Energy Systems, Power Management, Power Electronics, Electrical Machines and Drives
• Term: from 2014 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 262597430

For the transmission of electricity from offshore wind farms that are planned or in construction in North- and Baltic Sea over large distances to the urban areas in south- and west-Germany, the realization of a high-voltage-direct-current (HVDC) grid in addition to the existing AC-grid is currently in discussion. At the same time the construction of an HVDC grid in the North Sea for the connection of the neighbouring countries to each other and to the wind farms is also in discussion. This research project focuses on the development of a control structure for the HVDC converters, which connect the dc grid at multiple, remote locations with one or several AC-grids. The control structure shall on the one hand be able to control the DC-voltage decentrally, so that also large DC-grids are feasible. On the other hand, according to the known control processes in AC-grids, special means to handle the dc power flow shall be provided.Besides the pure distribution of the offshore generated power, such a dc grid also allows flexible power transmission services. This especially goes for the exchange of reserve power between the different AC-grids and the usage of storage power plants. The control shall be able to manage this reserve power transfer automatically and according to the actual demand.

• DFG Programme: Research Grants