Similar to synchronous generators (SGs)

symmetrical short-circuit faults can reduce the stability margin of grid-forming renewable power generation (GFM-RPG)

thereby heightening the risk of transient instability. While existing studies primarily examine single-machine infinite-bus systems

this work explores transient stability challenges inherent in paralleled GFM-RPG systems. First

through rigorous mathematical derivation

it establishes that the transient characteristics of paralleled systems can still be effectively characterized by a second-order motion equation. Subsequently

by applying the extended equal area criterion (EEAC) and numerical solutions to differential equations

the study uncovers the governing principles behind the variations in the critical clearing angle (CCA) and critical clearing time (CCT) for the paralleled GFM-RPG system under various operating conditions. Finally

to mitigate potential instability risks

two corrective strategies

namely adaptive damping enhancement and power switching control

are proposed to improve the transient stability of the paralleled system during symmetrical faults. Simulation results confirm the accuracy of the theoretical analysis and demonstrates the effectiveness of the proposed strategy.