Evaluation of HVDC interconnection models for considering its impact in real-time voltage stability assessment

An approach to evaluate the HVDC interconnections models to be used in real-time voltage stability assessment is proposed. The existing models for the HVDC interconnections, that are based on voltage source converter, were studied selecting the ones that are suitable for its application in Thevenin equivalent methods for voltage stability assessment. The proposed method is to evaluate the validity of the models by using synthetized PMU measurements from simulations and from PMUs connected to the Danish system. Wide-area measurements are used to estimate the HVDC model parameters which are needed to calculate a distance to the instability boundary. The parameters are benchmarked according to their expected uncertainty and its impact in the Thevenin equivalent methods is evaluated. The results show the used pre-processing procedure for the real PMU measurements and simple criterion for the evaluation of the parameter validity. The parameters calculated for all the selected models are between the expected uncertainty values for a time window of at least 2 cycles.