针对光伏打捆水电送出系统中接入电压等级选择影响系统安全的问题，本文旨在探究光伏高压侧与低压侧接入对水电站内部设备安全及电网稳定性的影响差异。以某大型水电站库区光伏项目为例，采用PSD-BPA 软件构建系统仿真模型，设置光伏高压侧（500kV）与低压侧（15 .75kV）两种接入方案，通过静态短路计算与动态暂态仿真进行对比分析。结果表明，高压侧接入使发电机15.75kV 及35kV 母线的短路电流显著降低，设备安全裕度增大；在500kV 和35kV 母线故障下，该方式功角摆幅更小、阻尼衰减更快、电压恢复更平稳。高压侧接入方式通过电气隔离有效避免了低压侧接入导致的短路电流过大风险，提升了系统暂态稳定性，是更优的工程实施方案。

To address the impact of access voltage level selection on system security in photovoltaic (PV)bundled hydropower transmission systems,this paper investigates the differences in the effects of high-voltage side versus low-voltage side PV access on the internal equipment safety of hydropower stations and power grid stability.Taking a large-scale PV project in a hydropower station reservoir area as a case study,a system simulation model was constructed using PSD-BPA software.Two PV access schemes —high-voltage side (500 kV)and low-voltage side (15 .75 kV)—were established for comparative analysis through static short-circuit calculations and dynamic transient simulations.The results indicate that high-voltage side access significantly reduces the short-circuit current at the 15.75 kV and 35 kV generator buses,thereby increasing the safety margin of equipment.In the event of faults at the 500 kV and 35 kV buses,this scheme demonstrates smaller power angle swings,faster damping attenuation,and smoother voltage recovery.Consequently,the high-voltage side access mode effectively mitigates the risk of excessive short-circuit current associated with low-voltage side access through electrical isolation,enhances system transient stability,and represents the superior engineering implementation solution.