Performance of wavelet-based damping estimation method under ambient conditions of the power system

The paper discusses performance evaluation of damping estimation methods and specifically evaluates the performance of a wavelet-based damping estimation method. The focus is on the damping estimation under the ambient conditions of the power system. Damping estimation results are reviewed in case of the simulated data because then real damping is known and can be compared with the estimated damping. Various degrees of complexity of the simulation models are used: linear single and double pole pair models, and a detailed nonlinear system model of the Nordic power system. In the linear models, the real damping of the modes can be analytically calculated and compared with the estimated damping. Damping estimation performance is studied in different operating conditions of the studied simulation models. The main results are: frequency estimates are better than the damping estimates, other oscillation modes may affect the damping estimation, poor damping can be estimated more accurately than high damping, and the performance of the method is nearly similar regardless of the complexity of the simulation model.