大功率中频变压器漏感计算及其校正方法

Calculation and Correction Method for Leakage Inductance of High-power Medium-frequency Transformer

为在设计阶段对大功率中频变压器漏感值进行准确法估算,基于中频变压器一维等效模型,根据漏磁场分布特征,通过能量法进行了变压器漏感参数解析公式推导。在此基础上,根据理想漏磁场模型与实际的差异,修正了解析公式中绕组的电导率与漏磁场的计算高度。通过比较两台样机在50 Hz^10 k Hz频段下的漏感实测与计算结果,证实了对这2个参数同时进行校正,可使变压器漏感计算误差减小到5%以内,并进一步分析了仍然存在的误差产生的原因。通过样机1与样机2的漏感值对比,证明了绕组交叉换位技术可有效减小变压器漏感。

In order to accurately estimate leakage inductance in the design of high-power medium frequency transformer（MFT）, on the basis of a one-dimensional leakage magnetic field model of MFT, we derived an analytical equation for leakage inductance of MFT by an energy method which is based on the characteristic of its distribution. Thereby, the conductivity of the winding and calculation altitude of the leakage magnetic field was corrected based on the difference between idealized assumptions and actual situation. Moreover, leakage inductance of two prototypes was calculated and measured from 50 Hz to 10 k Hz, verifying that error could be reduced to less than 5% by correcting both the parameters. The reasons for the still existing error were analyzed. The comparison between prototype 1 and 2 demonstrates that cross arrangement for the windings can reduce the leakage inductance value of the transformer.