计及安全风险的互联电网发电–备用两阶段联合优化模型

Generation-reserve Two-staged Joint Optimization Model for Interconnected Power Grid Considering Security Risks

互联电力系统之间的备用共享有利于提高系统的抗扰动能力和运行经济性。不合理的备用分配方案可能导致备用无法被有效调用,从而增加系统潜在风险。以多区域互联电网为研究对象,设计了多区域备用共享机制,构建了计及安全风险的发电–备用两阶段联合优化模型。针对风险评估,提出了一种基于蒙特卡洛模拟的场景生成、筛选及压缩方法,该方法考虑了新能源、负荷波动及发输变电设备的随机故障。随后,基于压缩后的场景,构建了考虑弃风惩罚和负荷削减的风险评估模型,并通过构建机组群备用约束给出了风险评估结果与联合优化的闭环迭代策略。最后,以IEEE-118节点系统为算例进行模拟仿真,详细分析了备用独立配置和联合共享两种模式下的经济效益及潜在风险,验证了考虑安全风险在发电–备用优化配置过程中的必要性及本文所提方法的有效性。

The reserve sharing among the interconnected power systems facilitates the improvements on their anti-disturbance capability and operating economy. However,an unreasonable reserve allocation scheme may lead to the ineffective utilization of the reserve, thus increasing the potential risks. Taking the multi-area interconnected power grid as the research object, a multi-area reserve sharing mechanism is designed, and a generation-reserve joint optimization model considering security risks is built. For the risk assessment, a scenario generating, screening, and compressing method based on the Monte Carlo Simulation is proposed. This method considers the new energy, the load fluctuations and the random failures of the power generation, transmission and transformation equipment. Then, based on these compressed scenarios, the risk assessment model considering the wind curtailment penalty and the load restriction is constructed. The risk assessment results and the closed-loop iteration strategy of the joint optimization are given by establishing the reserve constraints of unit groups. Finally, the IEEE 118-bus system is taken as an example for simulation. The economic benefits and the potential risks under both the independent reserve allocation and the joint reserve sharing modes are analyzed in detail, verifying the effectiveness of the proposed method and the necessity to consider the security risks in the process of optimal generation-reserve allocation.