基于有限元的高频变压器分布参数计算与分析

Calculation and Analysis of Distributed Parameters of High⁃frequency Transformer Based on Finite⁃solid⁃element Method

高频变压器的分布参数会影响其输出参数及性能,推导高频变压器副边分布电容以及漏感的解析表达式,发现绕组的绕制方式、分段分层结构、绝缘层厚度、绕组高度、绝缘介质等是影响其分布参数的主要因素。针对40 kV、20 kHz的高频变压器建立了电磁场有限元仿真模型,分别计算和分析了各因素对分布电容及漏感的影响规律。优化副边绕组分段分层结构,综合考虑漏感、分布电容及绕组损耗确定变压器绕组的绝缘厚度及高度,并据此设计加工了实验样机。测试结果表明分布电容和漏感的仿真计算结果与实测值的误差分别为9.5%和11.3%。仿真分析方法以及相关的规律结论为高频变压器的分布参数计算和结构设计提供了参考。

The distribution parameters of high⁃frequency transformer can affect its output parameters and perfor⁃mance.It is found by deriving the analytical expressions for the secondary distributed capacitance and leakage induc⁃tance of high⁃frequency transformer that the winding mode,segment and layered structure,insulation layer thickness,winding height and insulation medium are the main factors affecting its distribution parameters.A finite element sim⁃ulation model of electromagnetic field is set up for high⁃frequency transformers at 40 kV and 20 kHz,and the influ⁃ence of various factors on distributed capacitance and leakage inductance is calculated and analyzed.The insulation thickness and height of the transformer winding are determined by way of optimizing the segment and layered struc⁃ture of the secondary winding and of comprehensively considering leakage inductance,distributed capacitance and the winding losses and,on this basis,the experimental prototype is designed and processed.The test results show that the errors between the simulation calculation results of distributed capacitance and leakage inductance and the actually measured values are 9.5%and 11.3%,respectively.The simulation analysis method and relevant conclusions provide a reference for the calculation of distributed parameters and structural design of high⁃frequency transformer.