Damping to Low Frequency Oscillation Modes in DFIG-integrated Power System Based on Sensitivity to Controllable Loads
Integration of doubly-fed induction generators(DFIGs)intensifies low frequency oscillation(LFO).With power market and intelligent device,controllable loads may participate into damping control.Thus the damping ratios of the dangerous modes are affected by loads,which adds the difficulty of analytical expression to the eigen-sensitivity.The existing constant-impedance model does not show the impact of the composite load on the small-signal stability.The induction motor model is accurate but difficult to differentiate,and it is not suitable for the small signal stability analysis.In this paper,the ZIP load model is applied to derive the system state equation and avoid modeling difference in power flow and small-signal stability analysis.With the bridge of the sensitivity of power flow solution to the loads,an analytical model of the sensitivity of the damping ratios of the dangerous modes to the loads is proposed.The quasi-proportional resonance(quasi-PR)control is applied to adjust the load,and the sensitivity of the damping ratio is modified accordingly to improve the robustness of the damping control.The simulation results verify the control effect of the proposed algorithm.
doubly-fed induction generatorslow frequency oscillationdamping controlZIP loadquasi-PR controlsensitivity
万方数据
维普
