Transient Over-voltage Assessment for Renewable Powered Systems with Practical Case Studies

In a power system with high proportion of renewables, transient over-voltage after faults may lead to unplanned drop off of generation and threaten system stability. To address this issue, the paper develops a comprehensive procedure of transient over-voltage assessment for renewable powered systems. The procedure consists of such key steps as parameter collection, model development, and detailed simulation studies. Focuses are placed on the critical factors that would affect the accuracy of assessment. To validate the feasibility and efficiency of the procedure, a typical test system is modelled and analyzed, including an exploration of the impact of SVG control strategies. Studies indicate that transient over-voltage induced by severe faults would not be affected too much by the type of faults due to the converter current limit. Case studies have demonstrated that the assessment procedure can be practically used for large renewable powered systems.