Sub-synchronous oscillation coordinated damping optimization control of DFIG and SVG and self-optimization parameter tuning method

Currently, the power electronics-based devices including large-scale non-synchronized generators and reactive power compensators are widely used in the power grid. This would introduce the coupling interactions between the devices and the power grid, resulting in the new sub-synchronous oscillation phenomenon. It is a critical element for the stability operation of the power grid and the devices. Thus, in this paper, the sub-synchronous oscillation phenomenon of the power grid connected with large-scale wind power generation is analyzed in detail. Then, in order to damp the sub-synchronous oscillation, a coordinated damping optimization control strategy of the wind power generators and the reactive power compensator is proposed. The proposed coordinated control strategy track sub-synchronous oscillation current signal to correct corresponding control signal, which increases the damping of power electronics. The response characteristics of proposed control strategy are analyzed, and a self-optimization parameter tuning method based on sensitivity analysis is given. The simulation results validate the effectiveness and the availability of the proposed control strategy.