储能电池系统响应速度快、调节能力强，能够有效应对可再生能源随机性。然而，随着电池储能比例提高，其失效特性对电力系统可靠性的影响逐步增大。为此，本文提出了计及电池储能系统失效特性的电力系统运行可靠性评估方法。首先，基于通用生成函数建立了电池储能系统多维性能衰减概率模型，并进一步结合储能电池热失控失效预警概率，建立综合考虑电池储能失效的可用输出功率模型；然后，构建了计及电池储能系统失效的电力系统负荷削减模型，并基于蒙特卡洛模拟法，最终提出了考虑电池储能系统失效特性的电力系统可靠性评估方法，精准考虑电池储能系统热失控失效和多维性能衰减失效对电力系统可靠性的影响；最后，在IEEE RTS-79节点系统仿真分析，验证了本文所提方法的有效性。

The battery energy storage system (BESS) has fast response speed and strong adjustment ability, and can effectively cope with the randomness of renewable energy. However, as the proportion of battery energy storage increases, the impact of its failure characteristics on the power system reliability gradually increases. To this end, this paper proposes a power system operational reliability assessment method considering the failure characteristics of BESS. First, a multi-dimensional performance attenuation probability model of the BESS is established based on the general generating function and further combined with the thermal runaway failure warning probability of the BESS, an available output power model that comprehensively considers battery energy storage failure is established. Then, a load curtailment optimization model that takes the storage battery into account is constructed. Further, based on the Monte Carlo simulation method, the reliability assessment method that considers BESS failure is proposed. It can accurately consider thermal runaway failure and multi-dimensional performance attenuation failure of the BESS. Finally, the effectiveness of the method proposed in this article is verified in the IEEE RTS-79 bus system simulation.