考虑大型变压器退运的电力系统连锁故障风险评估

针对大型变压器突然退运造成的潮流转移问题,提出考虑大型变压器退运的电力系统连锁故障风险评估方法,即先利用变压器在线监测技术对变压器的老化失效和偶然停运进行分析,建立变压器失效模型;然后,从系统能量和结构角度对潮流转移支路状态进行评估,定义了能量转移因子和支路传输能力因子,并结合连通率和失负荷率指标,得到元件风险集;最后,根据连锁故障阶段模拟和自组织临界状态辨识方法,对连锁故障演化路径进行了全面预测。仿真结果验证了该方法的可靠性,可为能源互联网下的电网安全调度提供参考。

Risk Assessment of Cascaded Failures of Power Systems Considering Transformer Quit Operation

In view of the power flow transfer problem caused by the sudden transfer of large transformers, a risk assessment method for cascaded failure of power systems was proposed, which considers the redeployment of large transformers. The transformer on line monitoring technology was used to analyze transformer aging failure and accidental outage, and establish transformer failure model. Then, the state branch of power flow transfer was evaluated from the perspective of system energy and structure evaluation. The energy transfer factor and branch transmission capacity factor were defined. Combined with the connectivity rate and loss of load rate, the risk set of the components was obtained. According to cascaded failure stage simulation and self organized criticality identification method, cascaded failure evolution path was predicted. The simulation results show the reliability of the method, and it can provide reference for the power grid security scheduling under the energy Internet.