中文摘要：

计及了同步发电机有功和无功出力的耦合关系,详述了同步发电机的运行极限约束,在基于交流潮流的最优负荷削减模型中计入了这些运行约束。通过对RBTS可靠性测试系统的评估分析,定量研究了同步发电机运行极限约束对电网可靠性的影响。探索了发电机运行极限约束中励磁电势幅值,定子电流最大值和功率角最大值的不同取值对电力系统可靠性评估结果的影响。仿真结果表明：同步发电机运行极限约束对电力系统可靠性有明显影响,计入这些运行约束可使电网可靠性评估结果更加客观和符合工程实际。

英文摘要：

Considering the coupling of active and reactive power of synchronous generator,this paper elaborates synchronous generator operating limits in details,and then an optimal load shedding model based on AC power flow is established within the limits.Through the analysis assessment of RBTS reliability test system,a quantitative study of the impact of operating limits on the grid reliability is implemented.Meanwhile,the influence of the different parameter values in operating limits on power system reliability assessment result is investigated,such as the magnitude of excitation EMF,maximum stator current,maximum power angle.Simulation results show that synchronous generator operating limits have significant impact on power system reliability and make the result more objective and practical.