【摘要】 太阳风引发地磁暴时会在电网中产生地磁感应电流(Geomagnetically Induced Currents,GIC),准直流特性的GIC会导致变压器产生直流偏磁。阐述了GIC的产生原理,根据零序磁通的磁路情况分析了不同铁芯结构变压器受GIC影响的大小程度。基于MATLAB-SIMULINK仿真软件建立了三相三柱式变压器和三相组式变压器的直流偏磁模型,通过对比两种变压器在GIC作用下的励磁电流、磁链和谐波阶次来对比分析不同铁芯结构受GIC影响的程度。仿真结果表明,零序磁通回路磁阻小的铁芯结构变压器更易受到GIC的影响,产生明显的直流偏磁,励磁电流含有各阶次谐波,对电网的安全稳定运行带来一定的影响。更多还原

【Abstract】 Geomagnetic storms triggered by solar wind can cause geomagnetically induced currents(GIC)in power grid, and GIC with quasi-direct current will make transformer produce DC biasing magnetism. Description was made to generation principle of GIC, and analysis was made to the extent of the impact of GIC on transformer with different core structure according to magnetic circuit of zero sequence fl ux. The models of three-limb core form transformer and three single-phase cores with DC fl ux shift were built in simulink of Matlab. By the comparison of excitation current, fl ux linkage and harmonic orders of the two different transformers under the infl uence of GIC, the results show that the transformer with low reluctance of zero sequence fl ux is vulnerable to GIC. In this case, GIC causes apparent DC fl ux shift and excitation current has each order harmonic, which poses a threat to the safe and stable operation of the power grid.更多还原