【作者】 张强；

【导师】 郑峰；

【作者基本信息】 西安电子科技大学 ， 电机与电器， 2020， 硕士

【摘要】 电力电子技术快速发展,基于宽禁带半导体材料氮化镓(Ga N)器件的开关电源(SMPS)具有更快的开关速度,更短的上升时间,其降低了开关损耗,具有较高的功率密度和效率等优势,开始广泛应用于各类电能变换装置中。同时,更快的开关速度导致共模噪声的频谱向高频段发生扩展,即位于高频范围的共模噪声将上升到无法忍受的水平,使得整个系统的电磁兼容问题变得更加复杂。为了保证系统的稳定可靠运行,必须有效地抑制这些电磁噪声。抑制噪声最直接有效的方法是在开关电源系统中接入无源EMI滤波器。然而,无源EMI滤波器中电感和电容体积通常都非常庞大,且会随功率等级的提高而不断增加。为了提高系统的功率密度,考虑引入有源EMI滤波器来和无源EMI滤波器性能进行互补。这种混合EMI滤波器在体积、重量和性能之间取得了相当好的平衡,但是由于寄生参数的影响,它在高频区域的插入损耗性能表现很差,在高功率应用场合中,这个问题将变得更加严重。因此,如何有效地降低寄生参数对混合EMI滤波器的影响,是保证滤波器性能的一个必须考虑的问题。有效抑制高功率、高频率噪声是电磁兼容的一个具有挑战性的障碍,随着Ga N器件的使用、开关频率的提高,这个问题变得更加严重。本文首先对课题研究背景及意义进行了介绍,包括电磁兼容的研究背景、EMI滤波器研究现状和本课题选题意义。其次具体分析了常见EMI滤波器的拓扑类型和工作原理,并给出不同拓扑插入损耗的分析方法和表达式。再次,具体分析寄生参数对无源EMI滤波器、有源EMI滤波器和混合EMI滤波器性能的影响,通过插入损耗表达式拟合曲线和仿真的方式说明寄生参数对高频区域性能影响的程度。基于此提出一种新型寄生电感相消的混合EMI结构来有效抑制基于氮化镓器件开关电源的高频噪声,包括π型EMI滤波器和V_SC_C型有源EMI滤波器,其通过无源部分第二级电容引线电感与有源部分注入电容引线电感耦合相消来优化传统滤波器的高频局限性。再其次,具体分析两待相消支路载流情况、寄生电感大小和耦合情况对实际相消效果的影响,并通过理论分析和算法优化给出不同情况下对应优化策略,分析共模串联回路对相消效果的影响并给出解决策略。最后,通过仿真和搭建原理样机的方式来验证方案的可行性和准确性。本文提出的寄生参数相消的混合EMI滤波器可以有效解决基于氮化镓器件开关电源带来的电磁兼容问题,完善滤波器设计中高频寄生参数的有效优化,推动电能变换装置向小型化、轻量化的方向发展。更多还原

【Abstract】 The rapid development of power electronics technology leading to faster switching speed,shorter rise time,lower switching loss,as well as higher power density and efficiency of switching mode power supply(SMPS)based on wide band gap semiconductor material gallium nitride(GAN)devices,and it has been widely used in various power conversion devices.The faster switching speed leads to the spread of the common mode noise spectrum to the high frequency band,that is,the common mode noise in the high frequency range will rise to the intolerable level,which makes the electromagnetic compatibility of the whole system more complicated.In order to ensure the stable and reliable operation of the system,these electromagnetic interference must be effectively suppressed.The most direct and effective way to suppress electromagnetic interference is to connect a passive EMI filter to a switching mode power supply system.However,the volume of inductance and capacitance in passive EMI filter is generally very large,and it increases as the power level increases.In order to enhance the power density of the system,the complementation of active EMI filter and passive EMI filter are considered.The hybrid EMI filter balances three properties:volume,weight and performance.However,since the effect of parasitic parameters,their performance in the high frequency range is out of expectation.In high power applications,this problem is more serious.Therefore,how to effectively reduce the influence of parasitic parameters on the hybrid EMI filter and ensure the performance of the filter are problems that must be considered.Effective suppression of high power and high frequency electromagnetic noise is a challenging obstacle in EMC.With the use of Ga N devices and the increase of switching frequency,this problem becomes more serious.This thesis firstly introduces the research background of EMC,the research status of EMI filter and the significance of the subject.Then,the topology and working principle of common EMI filters are analyzed in detail,and the analysis methods and expressions of insertion loss in different topologies are given.Thirdly,considering the influence of parasitic parameters,analyzes the limitations ofπtype PEF and V_SC_C AEF in high frequency and high power,the degree of impact is illustrated by means of insertion loss expressions and simulations.A hybrid EMI filter structure with parasitic inductance cancellation is proposed to deal with this problem,including aπtype PEF and a V_SC_C AEF.The principle on magnetic flux cancellation to reduce the equivalent series inductance(ESL)on common mode(CM)capacitors of the passive EMI filter(PEF)and active EMI filter(AEF)simultaneously is highlighted.Then,the effects of current-carrying conditions,parasitic inductance,and coupling conditions on coupling cancellation in the two branches are analyzed in detail.The optimization problem about the CM capacitance calculation and placement is also addressed.Finally,we use a prototype to prove the effeteness of our method.The hybrid EMI filter with parasitic parameter cancellation is proposed in this thesis,which can effectively solve the electromagnetic compatibility problem caused by switching mode power supply based on Ga N device.It can improve the optimization strategy of high frequency parasitic parameter in filter design,and promote the development of power conversion device to miniaturization and lightweight.更多还原