Analysis of the Mechanism of Wind and Fire Bundling System's Subsynchronous Oscillation and Its Suppression Measures

In the wind-fire coupling system, the mechanism of subsynchronous oscillation in thermal power units is not yet clear. In this paper, a small signal coupling model of the whole system is established. Based on the eigenvalue analysis, the torsional vibration modes of the system are investigated, and the mechanism of subsynchronous oscillation is revealed in combination with the results of the characteristic value analysis. It is found that the sub-synchronous oscillation of the wind and fire bundle system is characterized by “electromechanical resonance” and “near mode frequency”. In addition, the paper provides suppression methods based on multi-branch power system stabilizers and verifies the validity of the analysis and the reasonableness of the suppression measures by using PSCAD/EMTDC.