|ZHOU Yanghan,HU Bo,SHAO Changzheng,HUANG Wei,XIE Kaigui.Cascading failure analysis of power system considering current carrying capability degradation of aging lines[J].Electric Power Automation Equipment,2023,43(11):188-194
|关键词: 电力系统 老化 线路的电流承载能力 停运概率 连锁故障路径
|Cascading failure analysis of power system considering current carrying capability degradation of aging lines
ZHOU Yanghan, HU Bo, SHAO Changzheng, HUANG Wei, XIE Kaigui
State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing University, Chongqing 400044, China
|The long-term aging effect leads to the degradation of current carrying capacity of transmission lines and the increase of aging failure risk, which will further worsen the risk of cascading failure. The aging effect of transmission lines on the cascading failure of the power systems is investigated. Based on the heat balance theory, the calculation model of the current carrying capability dependent on the aging of transmission lines is established, and the numerical correspondence between the current carrying capability and the operation year of transmission lines is expounded. On this basis, considering the aging effect of real-time power flow and transmission lines, a three-dimension mapping relationship including real-time power flow, operation year and outage probability is established, and the dynamic outage probability model of transmission lines is enhanced. Then, by introducing probabilistic threshold parameter, an improved cascading path search criterion based on outage probability model is established. Guided by the maximum probabilistic coupling event in the evolution process of cascading faults, the representative fault paths are screened while the low probability cascading failure paths are filtered. An example study is carried out by the improved IEEE 39-bus system. The numerical results indicate that after considering the aging effect of the transmission line, the number of cascading failure events triggered by single line accidents increases, the probability increases, the corresponding path order increases, and the risk of system cascading failure increases significantly, indicating that there is a significant correlation between the aging effect of the transmission line and the consequence of cascading failure.
|Key words: electric power systems aging current carrying capability outage probability cascading failure path