中文摘要：

为缓解大电网可靠性评估的计算复杂性,采取等值参数联合概率密度分布建模的方式开展了外网静态等值研究。在常规确定性静态Ward等值技术基础上,考虑外部区域发电机和线路随机故障,通过计算各种随机故障状态下的外网等值参数,即外网等值注入功率和外网等值串联支路阻抗,基于概率密度估计技术建立了等值参数的联合概率密度分布。外网静态概率等值模型克服了常规确定性静态Ward等值技术的不足,充分计入外网等值参数的随机性,减少了电网可靠性评估计算时间的同时提高了计算精度。对两区域RBTS系统和RTS79系统研究验证了其有效性和准确性。

英文摘要：

To alleviate the computational complexity of power system reliability evaluation, the probabilistic model of external system static equivalence was proposed in this paper. With using the traditional static Ward technique, the equivalent parameters of extern system in the state of random failures of generator and transmission line in the extern system were calculated, and then the joint probability density distribution for equivalent injection powers and series branch impedances of the extern system was achieved by utilizing probability density estimation technique. As the randomness of extern system equivalent parameters are considered, the proposed model can improve both calculation accuracy and efficiency. The proposed model is verified through the RBTS and IEEE-RTS79 test system.