兼顾技术经济性的永磁偏置型故障限流器优化配置算法

提出了一种兼顾技术性和经济性的大电网永磁偏置型故障限流器(Permanent-magnet-biased Saturation based Fault Current Limiter,PMFCL)优化配置算法.介绍了PMFCL限流机理,定义了短路电流裕量作为挑选超标节点的标准.将节点自阻抗作为节点短路电流水平的衡量指标,基于节点自阻抗增量,构建了兼顾全局限流效果与经济性的PMFCL优化配置评价函数.综合考虑了PMFCL启动条件和节点自阻抗对支路阻抗参数的灵敏度指标以缩小寻优空间,提出了PMFCL在大电网中配置优化算法.将该算法应用于IEEE 39节点标准算例,调用Matlab遗传算法函数完成仿真.结果表明,与不计及灵敏度相比,该算法寻优效率较高;所得最优配置方案能够使所有节点短路电流满足限流要求并保留一定裕量,对超标越严重的节点限流效果较好,验证了该算法的可行性及有效性.

Optimal Allocation Algorithm of Permanent magnet biased Saturation Based Fault Current Limiter Combining Technology and Economic Considerations

An algorithm for optimally allocating Permanent magnet biased Saturation based Fault Current Limiter (PMFCL) in large power grid was presented. The current limiting mechanism of PMFCLs was briefly introduced. Short circuit current margin was defined and can be used as the criteria of over standard bus selection. Bus self impedance was regarded as the measurement index of short circuit level. On account of the increment of bus self impedance, an optimal allocation evaluation function with consideration of the overall current limiting effect and economy was built. It is proposed that the starting condition of PMFCLs and the sensitivity index of bus self impedance with respect to the branch impedance can be utilized to greatly decrease the searching space. Finally, the algorithm for optimally allocating PMFCLs was concluded on the basis of evaluation function and sensitivity index. Simulation of IEEE 39 bus system was completed by using the proposed optimal allocation algorithm and genetic algorithm function of Matlab. The result suggests that the process of optimal allocation has relatively higher efficiency when compared with the method, in which sensitivity is not considered, the short current of over standard substations is restrained successfully and some abundant values are reserved. Furthermore, the effect of current limiting is better when the current exceeds the standard one more seriously. It verifies the feasibility and effectiveness of the proposed optimal allocation algorithm.