Suppression to Angular Oscillation among Synchronous Generators by Optimizing Parameters and Set-Points of Synchronous Condenser and High-Voltage DC

After losing one or two poles of the high-voltage DC (HVDC) line, power systems may experience angular oscillations among synchronous generators (SGs), possibly followed by tripping SGs and blackouts loads. To suppress oscillations, difficulty lies in optimization methods countermeasures. For former, parameter based on eigen-analysis for a given scenario is not suitable oscillation after large disturbance lasting several seconds longer. latter, adjusting active effective but responds slowly. Adjusting excitation system condensers (SCs) seldom studied since relation angle with reactive clearly described. control parameters remaining HVDC has limited effect enough. The set-points controller are adjusted to be restored oscillation, which different from parameters. In this paper, coordinated SC proposed SGs. At first, angles validated provide basis optimizing SC. Since analytical expression between related explicit periods different, an improved model trajectory sensitivity (TS) proposed. Based indication indices, constant current optimized decided. gradients objective function extended derive multiparameter numerical results validate accuracy TS comparing it perturbation method. time-domain analysis scenarios shows that AC/HVDC effectively suppressed model.