基于潮流追踪算法的自适应低频减载策略研究

低频减载（under frequency load shedding，UFLS）是防止电力系统频率崩溃的有效手段之一，它通过在系统的某些地点切除过负荷量，达到维护系统稳定的目的。为此，计及负荷的电压调节效应，提出一种改进的功率不平衡量计算方法，针对不同的扰动在线计算系统的减载总量；并利用邻接矩阵的稀疏性，结合邻接矩阵和比例分配原则提出了一种潮流追踪新算法，提高了潮流追踪算法的计算效率，将其应用于在线确定减载地点与分配减载量。仿真结果表明，新的自适应减载策略可靠性更高，能够有效防止欠切或过切，改善受扰系统减载后的频率恢复效果，并提高系统的电压稳定水平，对实际电力系统紧急控制研究具有重要意义。

Research on Adaptive UFLS Strategy Based on Power Flow Tracing Algorithm

Under frequency load shedding(UFLS) is one of the valid implementations to avoid system frequency collapses. It significantly ensures the stability of the power system by means of shedding excessive loads in certain places. Considering the regulating effect of voltage on the load, an improved method for the calculation of power imbalance is proposed. It calculates the total amount of load shedding for different disturbance online. Taking advantage of the sparsity of adjacency matrix, a new power flow tracing algorithm is proposed by combining the adjacency matrix with the principle of proportional distribution, which can improve the computing efficiency and can be applied in UFLS to determine the location and the corresponding quantity of the load shedding online. The simulation results show that the new adaptive UFLS method is more reliable and can both improve the frequency and the voltage recovery performance with less amount of load shedding.