Adaptive passive control for multi-terminal high voltage direct current systems
YANG Bo
HUANG Lin-ni
ZHANG Xiao-shun
YU Tao
Abstract：This paper develops a perturbation observer-based adaptive passive control (POAPC), which is applied to improve the system damping of voltage source converter-based multi-terminal high voltage direct current (VSC–MTDC) systems. A perturbation term is firstly defined to aggregate the combinatorial effect of interactions among each terminals, unmodelled dynamics and unknown time-varying external disturbances. Then an extended state is employed to represent the perturbation, which can be rapidly estimated online via a perturbation observer. Furthermore, an extra system damping can be injected into each terminal to improve the transient response through the passivation, while POAPC does not require an accurate system model and measurements of full states. Four case studies are undertaken on a four-terminal VSC–MTDC system, which demonstrate that POAPC can provide a better control performance with greater robustness over that of conventional proportional-integral (PI) control conventional passive control, and perturbation observer based sliding-mode control (POSMC). POAPC can effectively reduce the control error and overshoot of active power and reactive power. Meanwhile, its P2 peak value is reduced from 11%to around 0%, such that a great robustness can be realized.
Keywords：adaptive passive controlperturbation observerdamping systemVSC–MTDC systems
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：11( 637-647 )