Coordinated damping optimization control of sub-synchronous oscillation for DFIG and SVG

Abstract

Currently, the power electronics-based devices, including large-scale non-synchronized generators and reactive power compensators, are widely used in power grids. This helps introduce the coupling interactions between the devices and the power grid, resulting in a new sub-synchronous oscillation phenomenon. It is a critical element for the stability operation of the power grid and its devices. 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 for wind power generators and their reactive power compensators is proposed. The proposed coordinated control strategy tracks the sub-synchronous oscillation current signal to correct the corresponding control signal, which increases the damping of power electronics. The response characteristics of the proposed control strategy are analyzed, and a self-optimization parameter tuning method based on sensitivity analysis is proposed. The simulation results validate the effectiveness and the availability of the proposed control strategy.