考虑负载电流影响的500 kV变压器直流偏磁涡流损耗及温升效应研究

Study on DC Bias Eddy Current Loss and Temperature Rise Effect of 500kV Transformer Considering Load Current Influence

变压器直流偏磁电流量值和衍生干扰对变压器及电网安全的影响是需要研究的问题。以500kV单相壳式变压器铁芯结构和设计参数为案例,考虑负载电流变化和漏磁通路径等因素的影响,建立了500kV变压器三维有限元模型,通过仿真研究不同量值电流作用下变压器油箱和上下T型梁等支撑件的漏磁通损耗和温升效应,得到了这些支撑件漏磁通和温升明显增大的部位及直流偏磁电流的量值指标。

The influence of magnitude of DC bias current and derived disturbances on transformer and power grid security needs to be studied. Taking the core structure and design parameters of 500 kV single-phase shell transformer as an example, considering the influence of load current variation and magnetic flux leakage path, a three-dimensional finite element model of 500 kV transformer is established. The flux leakage loss and temperature rise effect of transformer oil tank and upper and lower T-beams under currents with different magnitudes are studied by simulation. The magnitude index of DC bias current and the location where the flux leakage and temperature rise of these supports increase significantly are obtained.