基于 SSO 多扰动输入机理分析的 DFIG-GSC 功率振荡抑制策略研究

Sub-synchronous oscillation (SSO) of power grid has become one of the main problems restricting the development of new energy. The power oscillation of grid-side converter (GSC) in doubly-fed induction generator (DFIG) under SSO was studied, and an oscillation suppression strategy based on adaptive quasi-resonant controller was proposed. Firstly, the multi-disturbance input mathematical model of SSO to GSC was established, and the properties of different disturbance inputs and their effects on GSC system were explored. And two different suppression methods for physical disturbance and signal disturbance were defined, namely compensation and filtering. Secondly, aiming at the problem of coupling oscillation caused by the output error of phase-locked loop (PLL) through coordinate transformation, the frequency domain mathematical model of PLL output error Angle was established, and an improved PLL was designed to eliminate the influence of output error on the signal disturbance of GSC. At the same time, an adaptive algorithm of quasi-resonant controller was designed, and a DFIG-GSC power oscillation suppression strategy based on adaptive quasi-resonant controller was proposed to eliminate the physical disturbance effect of SSO on GSC. Then, according to the above theoretical analysis and research, resonant controller was used to eliminate the estimation error of PLL. Finally, effectiveness of the proposed suppression strategy is verified by simulation and experimental results.