一种变压器高频模型在电网过电压中的应用与仿真

Application and Simulation of a kind of High-Frequency Transformer Model in Power Grid Overvoltage

变压器中性点过电压包含的高频分量使变压器工频模型的仿真结果无法准确反映变压器暂态过电压的实际情况。研究了变压器内部结构及原理,应用PSCAD软件,以某电网110kV系统为背景,使用变压器工频模型与变压器高频模型对该变电站非接地主变中性点不对称故障过电压进行了仿真比较,通过与理论计算数值的对比得出,该高频模型能够准确有效地仿真各种不对称故障过电压。

Because the overvoltage at transformer neutral point contains high-frequency component, the simulation result of the transformer power frequency model couldn’t be used to refiect the actual situation of transformer transient overvoltage. Study was made to the transformer internal structure and principle. In application of PSCAD software and with certain power grid 110 kV system as background, the transformer working frequency model and transformer high-frequency model were used to carry out simulation comparison for asymmetry fault overvoltage at non-grounding main transformer neutral point in substation. The theoretical calculation value comparison shows that the high-frequency model can correctly and effectively simulate various asymmetry fault overvoltage.