DC voltage margin adaptive droop control strategy of VSC-MTDC systems

• Main Authors: Zhi Ping Cheng, Yi Fan Wang, Zhong Wen Li, Jin Feng Gao
• Format: Article
• Language: English
• Published: Wiley 2019-04-01
• Series: The Journal of Engineering
• Subjects: voltage control; power transmission control; adaptive control; power grids; power generation control; voltage-source convertors; DC transmission networks; power generations systems; power coordination; power margin; converter stations; power huge fluctuation; DC voltage margin adaptive droop control strategy; VSC-MTDC systems; direct current voltage margin control strategy; DC grid; voltage source converter multiterminal direct current systems; DC voltage margin; Matlab
• Online Access: https://digital-library.theiet.org/content/journals/10.1049/joe.2018.8695

In this study, direct current (DC) voltage margin control strategy and droop control strategy of voltage source converter multi-terminal direct current (VSC-MTDC) are introduced firstly, and according to the characteristics of two control strategies, an adaptive droop control strategy of DC voltage margin is proposed. When the power fluctuation of DC grid is relatively smaller, some of converter stations which connect to the power generations systems are involved in power coordination to balance the power margin of the entire DC grid. When the power of DC grid suddenly changes and the power fluctuation is relatively larger, the converter stations that adopt the adaptive droop control strategy adjust power and can avoid some of them to lose the adjust ability due to full load and power huge fluctuation as far as possible. Finally, the simulation based on MATLAB validates the effectiveness of the strategy.