DC Voltage Droop Control Design for Multiterminal HVDC Systems Considering AC and DC Grid Dynamics

• Published in: IEEE transactions on power delivery Vol. 31; no. 2; pp. 575 - 585
• Main Authors: Prieto-Araujo, Eduardo, Egea-Alvarez, Agusti, Fekriasl, Sajjad, Gomis-Bellmunt, Oriol
• Format: Journal Article Publication
• Language: English
• Published: New York IEEE 01.04.2016; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: AC and dc grid interactions; Control systems; Design analysis; Design engineering; droop control; Dynamical systems; Dynamics; Electric converters; Electric potential; Energia eòlica; Energies; Estructures marines; HVDC; Mathematical model; multiterminal; offshore wind power; Parcs eòlics marins; Phase locked loops; Power conversion; Power system dynamics; Regulators; Voltage; Voltage control; Wind power plants; Àrees temàtiques de la UPC
• ISSN: 0885-8977; 1937-4208
• DOI: 10.1109/TPWRD.2015.2451531

This paper focuses on the droop-based dc voltage control design for multiterminal VSC-HVDC grid systems, considering the ac and the dc system dynamics. The droop control design relies on detailed linearized models of the complete multiterminal grid, including the different system dynamics, such as the dc grid, the ac grid, the ac connection filters, and the converter inner controllers. Based on the derived linear models, classical and modern control techniques are applied to design the different controllers, including a multivariable frequency analysis to design the grid voltage droop control. In combination with the droop control, a dc oscillation damping scheme is proposed in order to improve system performance. The control design is validated through simulations of a three-terminal system.