Modeling and Analysis of Voltage Ride-Through Performance of Inverter-Based Resources

Renewable energy systems, particularly inverter-based resources (IBRs) like solar photovoltaics, wind turbines, and batteries, are becoming an increasingly important part of the power grid. However, IBRs present a variety of new stability and reliability phenomena that require the development of more sophisticated computer models for use in power system simulations. One emerging issue is that of voltage ride-through (VRT) and the reliability of IBRs in the face of disturbances and transients in grid voltage. This thesis presents work on the development and use of new IBR modeling logic for the purpose of studying VRT dynamics. First, a positive-sequence grid-following model of IBR electrical controls was built in PSCAD, based on the existing framework developed by the Western Electricity Coordinating Council (WECC). This model was validated against its equivalent model in PSS/e. Second, new logic was developed in order to simulate VRT capabilities as outlined by recent standards developed by the IEEE. Third, the new model was used to perform a sensitivity study of a generic IBR's dynamic performance during a low-voltage disturbance. The results demonstrate that time constants associated with reactive current injection controls have the greatest impact on IBR VRT performance.