计及特高压输电线路影响的自组织临界电网风险评估方法

基于自组织临界性理论,在快过程分析中考虑电压控制,通过潮流优化计算和序贯蒙特卡洛模拟,对含特高压输电线路电网的连锁故障情况进行了较为全面的仿真分析。应用相关风险指标对停电风险进行了量化评估。根据系统自组织临界平衡过程,推导出在支路潮流与容量增长平衡建立时日均故障线路数与电网负荷增加率、支路恢复系数以及支路总数的关系,然后通过算例分析说明对电网应用自组织临界性理论进行风险评估的结果与负荷发展水平密切相关。最后应用改进后的自组织临界方法对含特高压输电线路的某区域电网进行停电风险评估,验证了研究工作的有效性。

A Modified Self-organized Criticality Method for Power System Risk Assessment Concerning Influences of Ultra-high-voltage Transmission Lines

Based on the self-organized criticality theory, and considering the voltage control in fast process, a comprehensive simulation analysis on the cascading failure conditions for power systems with ultra-high-voltage(UHV) transmission lines is conducted by optimal DC power flow calculation and serial Monte Carlo simulation. Then the power failure risks are assessed by related risk indices. According to the self-organized criticality balance progress, the relationship between the daily mean fault branch number, load increasing rate, branch restoration index and total branch number is derived at the time the balance between the power flow of branches and capacity increase is reached. Case studies show that the risk assessment results using the self-organized criticality method are closely related to the load development level. Finally, the modified self-organized criticality method is adopted to evaluate the power failure risks of regional power systems with UHV transmission lines, and the rationality of the theory analysis is verified.