Accommodation capability assessment of high-voltage direct current with a large-scale wind power integration system based on risk constraints of sub-synchronous oscillation

In order to research the new sub-synchronous oscillation (SSO) phenomenon caused by the wind power, first, this work studied the characteristics of the wind turbine in the frequency of the SSO, considering the characteristics of the wind controller simultaneously, and established the wind turbine and the power grid transmission model under the SSO propagation path. Then, the non-infinite equivalent model of the grid power model was proposed in order to change the strengthening degree. Third, a comprehensive evaluation index based on the oscillation energy was presented, and the capacity of the wind power from the frequency limit of the SSO was evaluated; meanwhile, the constraints of the SSO have been studied to maintain the stability of the power network. Finally, the rationality and effectiveness of the method were verified based on the IEEE 39-node model