Wind-thermal power bundled system with HVDC external transmission technology has become an ideal solution for long-distance transmission.For suppressing the issue of multi-modal sub-synchronous oscillationgenerated by the wind-thermal power bundled system and excavating the suppression ability of fully-controlled flexible AC power transmission device with energy storage to the sub-synchronous oscillation

a kind of suppression method based on the STATCOM/BESS is proposed.Firstly

the participation matrix is obtained by the sue feature analysis method

the proportion of each control parameter in the influence of each oscillation modal is studied in accordance with the corresponding participation factors of each STATCOM/BESS control parameters in each oscillation mode.Secondly

the current decoupling capability of STATCOM/BESS is used

an improved ADRC damping controller is added to the current inner loop control loop to suppress multi-modal oscillationand the improved QPSO is used to coordinate and optimize the parameters of the additional damping controller.The validity and adaptability of the method are verified by PSCAD/EMTDC simulation

showing that the suppression strategy can effectively suppress the sub-synchronous oscillation of the DC delivery system and improve the operational stability of the system.