NI Binye, XIANG Wang, LU Xiaojun, et al. Low-frequency oscillation suppression using flexible DC grid based on state feedback supplementary damping control[J]. 2019, 39(3): 45-50+57.
NI Binye, XIANG Wang, LU Xiaojun, et al. Low-frequency oscillation suppression using flexible DC grid based on state feedback supplementary damping control[J]. 2019, 39(3): 45-50+57. DOI: 10.16081/j.issn.1006-6047.2019.03.007.
To improve the dynamic stability of AC/DC interconnected system
an approach that uses VSC-MTDC(Voltage Source Converter based Multi-Terminal Direct Current) to damp low-frequency oscillations is proposed.The oscillation mode of AC/DC system is analyzed
and the influences of DC grids on the stability of AC grids are studied. Based on the modal analysis
supplementary damping controller of VSC-MTDC is designed. This controller can output supplementary control signals and regulate the active power of each converter during oscillation to suppress the system oscillation. Simulations are carried on New England 10-machine power system with four-terminal DC grid. Test results indicate that the proposed controller damps the low-frequency oscillation and improves the system dynamic performance.