【作者】 梁斌；

【导师】 魏克新；

【作者基本信息】 天津大学 ， 控制理论与控制工程， 2012， 博士

【摘要】 本文致力于功率变换器传导电磁干扰的建模研究。从干扰源、干扰耦合路径两个角度分析、研究了变换器传导电磁干扰的耦合机理，建立了传导电磁干扰的模型。本文的主要工作包括：1.基于非对称规则采样策略，构建了功率变换器相应的差模和共模电磁干扰源模型。使用该模型进行了频域计算，从而导出了相应的干扰源频谱。对共模及差模干扰分布在变换器开关频率及其倍数附近的规律进行了概括，而后在不同的调制比下，对传导电磁干扰的变化趋势进行了分析。2.对功率变换器主电路部分的高频寄生参数进行了研究。采用理论分析和实测相结合的方式提取了电路中的寄生参数。研究了变换器中共模、差模传导电磁干扰的耦合路径，建立了包含高频寄生参数的传导电磁干扰耦合路径的精确模型。使用频域计算的方法得到了相应的干扰频谱。3.通过引入“影响因子”的概念来评估不同寄生参数的变化对系统整体电磁干扰性能影响的严重程度，据此构建了精度较高的简化的电磁干扰耦合路径模型。根据已建立的精确模型，使用仿真的方法分析了各个参数变化下的系统整体电磁干扰的变化规律，找到了当整体参数在一定范围内变化时的系统电磁干扰的最大变化阈度，并以此为基准对各个参数分别进行分析，找到了其各自在一定范围内变化时的“影响因子”。由于各个寄生参数在不同频段内对系统电磁干扰的影响程度不同，该部分根据所得到的影响因子规律表对系统的主导寄生参数进行了分组、分频段的讨论。研究结果表明，各个参数对差模和共模干扰的“影响因子”不尽相同，差模和共模干扰的主导寄生参数也有较大区别。基于相应的定量分析，最终建立了较为精确且简化的干扰耦合路径模型。设计实验，以一台大功率变换器为研究对象对干扰耦合路径的精确模型和简化模型分别进行了实验测试。实验结果表明，所建带寄生参数的精确模型的预测结果大大优于不带寄生参数时的预测结果；而相对于精确模型，所建简化模型的计算量的降低比率高于精度的损失比率。更多还原

【Abstract】 This thesis devoted to research on modeling of conducted electromagnetic interference of power converter. At first, this thesis studies the converter conduction mechanism of electromagnetic interference from two aspects of the interference sources and interference path; establishes the relevant model of EMI. The main works of this thesis are:1. Models to predict the common mode (CM) and the differential mode (DM) noise source of PWM converter is presented with asymmetric regular sampling modulation. A direct calculation method in frequency domain is proposed for the deduction of frequency spectrum of noise source. The distribution of CM and DM noise around the switching frequency and its multiple has been summarized to compare the changing relation of the interference between different modulation ration. Some patterns of such change have been found. In addition, with software, the time domain simulation along with its Fourier transform of the conducted Electromagnetic Interference of a three-phase rectifier verifies the correctness of the analysis results of proposed predictive model using the frequency domain theory. The modeling method described can be readily extended to a three-phase PWM inverter.2. The the thesis presents a new approach for modeling of the conducted electromagnetic interference prediction for widely used converter systems. Coupling paths and mechanism of differential mode interference and common mode interference have been analyzed. Models to predict the high-frequency noise of PWM converter system are created. A direct calculation method in frequency domain is proposed for the deduction of frequency spectrum. A method is given for obtaining the parasitic parameters and topological structure of the model.3. On the basis of predecessors’research conclusion, simplified DM and CM EMI models on high frequency coupling paths had been established. Based on the preceding section about the conclusion of precision high-frequency coupling paths model, the rule of the whole EMI under multiple parameters’variation. Range of variation was found when the whole parameters within certain scope. Each parasitic parameters were analyzed respectively reference to this standard, and "impact factors" were summaried. Due to the influence of different frequency range and different paremeters is different from one another, dividited the parameters into groups, through rule table of impact factor. The results of the study show that the impact factor of DM EMI is different under different parasitic parameters, and the main parasitic parameters have big difference between eachother. Based on the corresponding quantitative analysis, a more accurate simplified interference prediction model set up finally.An experimental investigation of conducted emission from an actual high-power rectifier system is described.The experimental results show that the accurate of the model with parasitic parameters is higher than that of the model without parasitic parameters; And relative to the accurate model, reduce ratio of the calculation amount of the simplified model is higher than the loss ratio of calculation accuracy.更多还原