考虑动态输送容量机制的电力传输线过载风险评估

传输线动态输送容量(DLR)技术旨在使用动态环境参数计算整定传输线输送容量,相较于传输线静态输送容量整定方法,可真实反映传输线实时传输功率上限.然而,DLR数值的计算依赖于风速、光照强度、温度等不确定性较强且难以准确预测的环境参数,换言之,依照DLR机制整定得到的传输线最大传输功率上限也具有不确定性.若其预测偏差过大,可能会造成传输线过载,严重的甚至会引发电网连锁故障.为此,文中提出一种考虑DLR不确定性的电力传输线过载风险评估方法,以盒式不确定性集合描述传输线输送容量不确定性,将其过载风险作为评估指标,优化传输线零过载范围.文中提出的评估问题数学上属于两阶段鲁棒优化问题,应用列与约束生成算法实现模型的高效求解.最后,在搭建的测试系统中验证所提模型及算法的有效性.

Overload Risk Assessment of Power Transmission Line Considering Dynamic Line Rating

The purpose of dynamic line rating (DLR) technology is using dynamic environment parameters to calculate and set the ampere capacity of transmission lines. Compared with the setting method of the static line rating for transmission lines, the DLR technology can truly reflect the upper limit of real-time transmission power of the transmission line. However, the calculation of DLR values relies on environmental parameters that are highly uncertain and difficult to be accurately predicted, such as wind speed, solar radiation intensity and temperature. In other words, the upper limit of the maximum transmission power of the transmission line which is set according to the DLR mechanism is also uncertain. If the prediction deviation is too large, it may cause the transmission line overload, and even lead to the grid cascading fault. Therefore, this paper proposes a risk assessment method of power transmission line overload considering the DLR uncertainty. The uncertainty of the transmission line rating is described by the box uncertainty set, and the overload risk is taken as the assessment index to optimize the zero overload range of the transmission line. The evaluation problem in this paper mathematically belongs to a kind of two-stage robust optimization problem. The efficient solution of the model is realized by using column-and-constraints generation algorithm. Finally, the validity of the proposed model and algorithm is verified in the built test system.