Power Angle Oscillation Suppression Based on Coordinated Optimization to Doubly-Fed Induction Generator and High-Voltage DC

With the advantage of large-capacity and stability, the line commutated converter high-voltage direct current (LCC-HVDC) has been developed greatly together with the renewable energy, such as the doubly-fed induction generators (DFIGs). To suppress the power angle oscillations among the synchronous generators (SGs), the coordinated optimization to the DFIG and the HVDC may be applied. This paper proposes the coordinated optimization scheme to the power oscillation damper (POD) of the DFIGs and the additional damping controller (ADC) of the HVDC lines with the trajectory sensitivity (TS). The rotor speed of the SGs is taken as the input of the DFIG-POD and the tie-line power is taken as the input of the ADC of the HVDC. The dynamic model of the AC/HVDC power system with the DFIG is established. The analytical expression of the TS of the system is derived to provide the gradient information. Aiming at the minimization of the power angular oscillations, and calculating the TS of the power angles to the control parameters of the DFIG-POD and the ADC of the HVDC, the gradient information is obtained to derive the multi-parameter optimization scheme. The simulations are given to validate the optimization effect of the proposed scheme on the power angular oscillation.