An advanced small-signal model of multi-terminal MMC-HVDC for power systems stability analysis based on dynamic phasors

This paper proposes an advanced small-signal of multi-terminal MMC-HVDC for large-scale systems stability analysis based on dynamic phasors and state-space, and this advanced model. In accordance with active and passive network control strategies for multi-terminal MMC-HVDC, the matchable small-signal stability models contained higher harmonics are conducted, and related theoretical derivation is carried out. The comparison of the advanced small-signal model, electromagnetic-transient model, and traditional small-signal state-space model is performed under a typical multi-terminal MMC-HVDC network with offshore wind generation. According to simulation, the advanced small-signal model can successfully follow the electromechanical transient response with small errors and predict the damped oscillations. Consequently, the validity and applicability of the proposed model are well confirmed.