Coordinate Optimization Damping Control of Subsynchronous Oscillation of Doubly-Fed Wind Turbines

In recent years, new energy technologies have been booming, and global installed power generation capacity has been increasing. Doubly-fed wind turbines are widely used in gridconnected series compensation systems. However, subsynchronous oscillation(SSO) problems occur, which may severely affect the operation of the power grid. In this study, a time-domain simulation model was built and a number of experiments were carried out to explore the influencing factors of sub-synchronous oscillation of doubly-fed wind turbines in a series-compensated grid-connected system. A grid and rotor coordination control strategy is proposed to suppress the sub-synchronous oscillation problem. A model is built on the RTLAB platform, and experimental tests are conducted. The results indicate that the proposed control strategy can effectively suppress subsynchronous oscillation and significantly reduce the amplitude of the oscillation. Furthermore, compared to unilateral control, the coordinate control on both the grid and rotor sides achieves better results, enhancing the safe and stable operation of the power grid.