Sub-synchronous Oscillation risk assessment method of doubly-fed wind power system considering random factors

Regarding the risk of subsynchronous oscillation(SSO) when the doubly fed wind power system is connected to the power grid through series compensation lines, this paper presents a sensitivity risk assessment method based on the probability distribution of modal damping ratio of SSO. Firstly, the small-signal model of a doubly-fed wind power system is established,and the damping ratio of the SSO mode of the wind power system is calculated using eigenvalue and Prony analysis methods; Then, considering the randomness of wind speed, the probability of wind farm SSO caused by random wind speed fluctuations is studied, the risk degree of SSO caused by random load fluctuations in the wind power system was considered. Finally, the effectiveness and feasibility of the proposed method were verified through simulation.