Transient Characteristics and Transient Power Angle Stability Analysis of Synchronous Condenser Considering the Influence of Different Renewable Energy Active Outputs

INTRODUCTION: Synchronous condensers (SCs) are installed near renewable energy stations to suppress transient overvoltage and enhance transmission capacity, but they increase SC transient power-angle instability risk post-fault. OBJECTIVES: To analyze the transient instability mechanism of SC, the transient characteristics during and after faults, and the influence law of different renewable energy active power outputs on SC transient power-angle stability. METHODS: First, a transient stability analysis model of SC is established. Second, based on the equal-area criterion, the mechanism of SC transient power-angle instability is analyzed, followed by an analysis of the SC’s transient characteristics. Finally, combined with the trajectory analysis method, the influence mechanism of different renewable energy active power outputs on SC transient power-angle stability is revealed from the perspective of stability indices. RESULTS: By building a simplified simulation model of the renewable energy transmission system in PSASP, the transient parameter results and stability indices of SC under different operating conditions are obtained, which verifies the correctness of the mechanism analysis in this paper. CONCLUSION: Fault-induced reverse active power absorption accelerates SC rotors and triggers transient instability, and higher renewable energy output intensifies SC power-angle swing, aggravates voltage drop and reduces stability index.