输电线路的雷击跳闸概率预测计算新方法

如何实现雷电故障的预警及跳闸概率的计算,对于电力系统防御雷击故障具有积极意义。提出了基于三时次雷区信息的电网雷击跳闸概率计算新方法。首先,根据每个时次的雷电监测信息,基于图像识别技术识别雷电发生区域;然后,以优化的方法确定雷区发展最佳轨迹;根据当前时次及之前的连续2个时次的雷区信息及发展轨迹,构成三时次相关雷区信息,并进行下一时次雷区相关信息的预报,包括雷区特性变化量(雷区面积、雷电流强度、雷区落雷概率);进而,计算位于雷击预报范围内的输电线路跳闸概率。该方法因利用了较多的雷电监测信息而具有较高的雷区预测准确性,相应的线路雷击跳闸概率也具有较高的准确率而可以作为雷击跳闸预警指标。算例证明了所述方法的有效性。

A New Prediction Calculation Method of Transmission Lines Lightning Trip Probability

Lightning faults early warning and trip probability calculation have a positive significance for power system protection against lightning faults. A novel algorithm for calculating lightning trip probability based on lightning subareas information at three adjacent time intervals is proposed. Firstly, lightning subareas are identified based on image recognition technology according to lightning monitoring information at each time interval. Then the optimal trajectory of lightning subareas is determined by the optimization method. The lightning subareas information at current time interval, previous adjacent time interval and the trajectory of lightning subareas constitute the lightning subareas information at three adjacent time intervals, based on which the relevant information, including variations of lightning subareas characteristics (area, lightning current intensity, lightning probability of the lightning subarea) at next time interval are forecasted. Finally, the trip probability of the transmission lines within the forecasted lightning subareas are calculated. Since more lighting monitoring information is utilized, the method proposed has higher precision of lighting area forecast. Accordingly, the lines trip probability also has higher precision and could be used as the lighting warning index. The results of the samples show the validity of the proposed method.