功率变换器变压器的EMI特性研究

发布时间：2018-01-09 06:32

本文关键词：功率变换器变压器的EMI特性研究　出处：《福州大学》2014年硕士论文　论文类型：学位论文

【摘要】：,电磁兼容问题是功率变换器理论和技术的重要组成部分,隔离式结构是功率变换器中的常用拓扑,作为隔离器件的变压器对电磁兼容特性具有十分重要的影响。本文以变压器为研究对象,主要研究了变压器的EMI特性,并建立了功率变换器变压器的电、磁综合模型,不仅具有理论意义,而且具有很好的实用性。论文首先总结了变压器EMI特性的研究及发展现状,明确了变压器的容性分布参数是影响EMI噪声的关键因素之一。指出变压器的共模端口有效电容能反映变压器对共模EMI噪声的抑制能力,介绍了共模端口有效电容的计算和测量方法,并分析了变压器不同结构、不同连接端子选择以及辅助绕组的不同位置对共模端口有效电容的影响,从而明确这些因素对变压器EMI特性的影响。通过分析变压器分布电容对共模EMI噪声电流的抑制特性以及电场储能特性,分析了能够同时反映一端口能量储存特性和二端口电磁噪声抑制特性的高频变压器三电容模型,并对多层绕组、多种绕组结构安排等情况进行了推导分析,总结了各种情况下容性模型的结构及参数变化规律。对变压器的EMI特性进一步研究指出：变压器的EMI噪声特性参数在高频段范围内不是单纯的容性性质,仅用容性分布参数来表征变压器的传导EMI特性与实际情况存在较大偏差。在三电容模型的基础上,提出了考虑变压器绕组的电位分布和磁场影响的电、磁综合新模型,模型中用互感解耦得到的电感来表征变压器插入损耗的感性状态。为了使模型更好地适用于不同匝比的变压器中,提出了电、磁综合改进型模型和可以应用于实际仿真中的电、磁综合统一模型。以反激式功率变换器为研究平台,分析了其共模传导噪声耦合路径和差模传导噪声耦合路径,指出变压器的分布参数只影响变换器的共模噪声,而对差模噪声几乎没有影响。对研究对象的实测插入损耗曲线与所建立的电。磁模型的插入损耗曲线进行对比,对比结果验证模型的准确性。在此基础上利用建立的变压器电、磁综合统一模型对研究样机系统的传导EMI进行仿真预测,并将仿真得到的共模噪声频谱与样机的实测共模曲线进行了对比,对比结果验证了模型的实用性和有效性。
[Abstract]:The electromagnetic compatibility problem, is an important part of the theory and technology of power converter, isolated structure is commonly used in the power converter topology, as transformer isolation device has an important influence on the characteristics of electromagnetic compatibility. The transformer as the research object, the main characteristics of EMI transformer is studied, and the establishment of a power converter transformer electric, magnetic integrated model, not only has theoretical significance, but also has good practicability. This paper summarizes the present situation of research and development of EMI transformer, the capacitive distribution parameters of the transformer is one of the key factors influencing the EMI noise. It is pointed out that the common port effective capacitance of the transformer can reflect the inhibition ability of transformer EMI common mode noise, introduces the calculation and measurement methods for common port effective capacitance, and analyzes the different transformer structure, different connecting terminals to choose Effect of different position and the auxiliary winding of the common mode port effective capacitance, in order to determine the effect of these factors on the characteristics of EMI transformer. By inhibiting the characteristic analysis of transformer winding capacitance in EMI common mode noise current and electric energy storage characteristics, analyzed to reflect the characteristics of a high frequency transformer energy storage port and two port electromagnetic noise suppression the three capacitor model, and the multilayer winding, a variety of winding arrangement situation is analyzed, summarized the structure and parameters of capacitive model under various conditions. The characteristics of EMI transformer further study pointed out: EMI noise characteristic parameters of the transformer in the high frequency range is not purely capacitive nature, only transmission characteristics of EMI capacitive distribution parameters of the transformer and the actual situation there is a big deviation. Based on the three capacitor model, is proposed Considering the potential distribution and the influence of magnetic field of the transformer winding power, new model of comprehensive magnetic inductance obtained by mutual decoupling model by the transformer insertion loss of emotional state. In order to make the model better for different turn ratio transformer, the electric, magnetic and synthetically improved model can be applied to the actual simulation the electric and magnetic integrated model. The flyback power converter as the research platform, analyzes the transmission noise coupling paths of the common mode and differential mode noise coupling path, pointed out that the distribution parameters of the transformer affects only the common mode noise of the converter, and has little effect on the differential mode noise. The measured insertion loss to the research object the curve and the established model are compared. The electric magnetic insertion loss curve, the results verify the accuracy of the model. On the basis of the establishment of power transformer, magnetic integrated model The conduction EMI of the prototype system is simulated and predicted, and the common mode noise spectrum obtained by simulation is compared with the measured common mode curve of the prototype. The comparison results verify the practicability and effectiveness of the model.

【学位授予单位】：福州大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM401

【相似文献】