考虑中频变压器非理想几何结构的通用漏感解析模型

General analytical model of leakage inductance for medium frequency transformer considering non-ideal geometric structures

中频变压器非理想几何结构引起的畸变磁场对漏感解析计算精度有较大影响,进而影响变压器设计及变换器运行特性和效率特性。首先针对副边绕组为非理想几何结构的漏感解析计算问题,基于叠加定理和洛氏高度等效方法,将传统只考虑纵向漏磁场的一维模型,改进为综合考虑纵向和横向漏磁场的二维模型,显著提升计算精度,并依据此模型提出一种通用漏感优化方法。进一步,针对原副边均为非理想几何结构情况,引入洛氏叠加区域,将原副边非正交且耦合的横向漏磁场能量考虑在内,提出一种计及中频变压器非理想几何因素的通用解析模型,计算误差在7.5%以下。仿真和实验验证了模型的准确性和通用性。

The distorted magnetic field caused by the non-ideal geometric structure(NIGS)of the medium frequency transformer(MFT)has a great influence on the analytical calculation accuracy of leakage inductance,which in turn affects the transformer design and the operating and efficiency characteristics of the converter.Aiming at the analytical calculation accuracy problem of the leakage inductance with NIGS of the secondary-side winding,based on the superposition theorem and Rogowski height equivalent method,the traditional one-dimensional model that only considers the longitudinal leakage magnetic field is improved to the two-dimensional model which considers both the longitudinal and transverse leakage magne-tic field,which significantly increases the calculation accuracy.Based on this model,a general leakage inductance optimization method is also proposed.Furthermore,in view of the NIGS of the primary and secon-dary sides,the Rogowski superposition region is introduced,and the non-orthogonal and coupled transverse leakage magnetic field energy is considered.The general analytical model that considers the NIGS of the MFT is proposed.The calculation error is less than 7.5%.Simulation and experiment verify the accuracy and versatility of the model.