The simultaneous entry of large-scale wind turbines into low-voltage ride-through (LVRT) in wind-thermal bundled power systems can significantly impact on the transient power angle stability of the system. To reveal the evolution law of power angle stability in high proportion wind power transmission systems, the influence mechanism of active power recovery characteristics on transient power angle stability after LVRT is theoretically analyzed first, and a power angle stability margin calculation method considering the time-varying characteristics of active power recovery is proposed. Next, based on this analysis, three evolutionary scenarios for high wind power penetration systems are considered: equal growth of critical wind power and remaining system load; equal replacement of synchronous generator output with critical wind power; and equal replacement of synchronous generators with critical wind power leading to generator startup. Using the equal area criterion, an evolutionary law of power angle stability is then derived and analyzed. Finally, simulations on both a single-machine infinite bus system and a real-world regional power grid verify the evolutionary characteristics of transient stability in high wind power penetration scenarios.