Subsynchronous oscillation suppression method for wind power plant grid-connected system based on stability control device

The invention discloses a subsynchronous oscillation suppression method for a wind power plant grid-connected system based on a stability control device, and aims to solve the technical problem that a subsynchronous oscillation stability control suppression strategy mechanism for a large-scale wind power access power system is unclear in the prior art. Based on the off-line electromechanical data, obtaining the impedance of the large-scale wind power access power grid side according to the power grid side topology; when the stability control device detects that the subsynchronous oscillation power component in the line reaches a set threshold value, the real-time impedance of the wind power plant is measured on line; calculating the total impedance of the current system according to the topological structure of the actual system, and then respectively calculating the real part of the total impedance of the system after the 1-m branches are cut off until the real part of the total impedance is greater than 0;