典型单相非线性负荷谐波模型及谐波特性研究

发布时间：2018-05-14 05:14

本文选题：非线性负荷 + 谐波耦合导纳矩阵模型　；参考：《重庆大学》2014年硕士论文

【摘要】：低压配电系统中广泛分布着大量非线性负荷，随着电力电子技术的发展，这些非线性负荷的种类和数量还会不断增长。由于这些负荷的电流总谐波畸变率大(有些甚至超过100%)，严重影响系统的电能质量，因此其谐波问题一直是学者们关注、研究的课题。本文深入研究了单相不可控桥式整流电容滤波类负荷的谐波耦合导纳矩阵模型，并改进了原有的模型，建立起了精确的谐波耦合导纳矩阵模型。利用这一谐波模型，分析研究了该类负荷的谐波衰减特性，提出了两个表征负荷谐波衰减效应的新指标；另一方面，本文还分析了谐波耦合导纳矩阵模型与谐波诺顿模型之间的关系，并对谐波诺顿模型成立条件、参数求解等方面的问题进行了研究。具体来说，本文的主要工作如下： ①通过改进求解电路的方法，得到单相不可控桥式整流电容滤波电路的精确解，在此基础上建立了基于这类电路的非线性负荷的精确谐波耦合导纳矩阵模型。 ②针对个人电脑、液晶显示器等典型单相非线性负荷的等效电路建立了一种有效的电路参数估计方法，在验证这种方法切实有效的基础上利用其对上述谐波模型进行验证。 ③利用本文建立的谐波耦合导纳矩阵模型分析典型单相非线性负荷的谐波特性及其谐波衰减(或放大)效应的机理和主要影响因素。在此基础之上提出了两个表征谐波衰减特性的新指标，，通过仿真验证了这两个指标的有效性。 ④对谐波诺顿模型与谐波耦合导纳矩阵模型之间的关系以及谐波诺顿模型成立条件、模型参数变化、模型参数求解等方面的问题进行研究，指出了传统的求解谐波诺顿模型参数的问题，并给出了改进方法。通过实验验证了改进后的谐波诺顿模型的有效性。
[Abstract]:A large number of nonlinear loads are widely distributed in low-voltage distribution systems. With the development of power electronics technology, the types and quantities of these nonlinear loads will continue to increase. Because the total harmonic distortion rate of the current of these loads is large (some even more than 100), it seriously affects the power quality of the system, so the harmonic problem has always been concerned and studied by scholars. In this paper, the harmonic coupling admittance matrix model of single-phase uncontrollable bridge rectifier capacitor filter is studied, and the original model is improved, and the accurate harmonic coupling admittance matrix model is established. By using this harmonic model, the harmonic attenuation characteristics of this kind of load are analyzed, and two new indexes are proposed to characterize the harmonic attenuation effect of the load. This paper also analyzes the relationship between harmonic coupled admittance matrix model and harmonic Norton model, and studies the establishment condition and parameter solution of harmonic Norton model. Specifically, the main work of this paper is as follows: 1 by improving the method of solving the circuit, the exact solution of single-phase uncontrollable bridge rectifier capacitor filter circuit is obtained, and the accurate harmonic coupling admittance matrix model of nonlinear load based on this kind of circuit is established. (2) an effective circuit parameter estimation method for typical single-phase nonlinear load equivalent circuits such as personal computer and liquid crystal display is established. The method is used to verify the harmonic model mentioned above on the basis of verifying the effectiveness of this method. 3Using the harmonic coupling admittance matrix model established in this paper, the harmonic characteristics of typical single-phase nonlinear load, the mechanism of harmonic attenuation (or amplification) effect and the main influencing factors are analyzed. On this basis, two new indexes are proposed to characterize the harmonic attenuation characteristics, and the effectiveness of the two indexes is verified by simulation. 4. The relationship between harmonic Norton model and harmonic coupled admittance matrix model, the establishment condition of harmonic Norton model, the variation of model parameters and the solution of model parameters are studied. The traditional problem of solving the parameters of harmonic Norton model is pointed out, and the improved method is given. The effectiveness of the improved harmonic Norton model is verified by experiments.
【学位授予单位】：重庆大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM714

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