峰值电流模式开关功率变换器的动态斜坡补偿策略研究

发布时间：2018-03-04 17:03

本文选题：开关功率变换器　切入点：快变不稳定行为　出处：《重庆大学》2014年硕士论文　论文类型：学位论文

【摘要】：开关功率变换器集合了功率管非线性元件和储能元件，其工作特性表现为时域分段线性特点，具有强耦合非线性特性，不仅会给电力系统注入大量谐波，而且当系统参数发生变化时，还会出现丰富的不稳定现象，如次谐波振荡、低频振荡等。这些不稳定行为的存在造成开关功率变换器系统的工作性能恶化。为此，本文以峰值电流模式开关功率变换器的快变不稳定行为(如次谐波)的动态斜坡补偿(DSC，dynamical slope compensation)控制策略，结合典型的DC/DC Buck变换器和Boost PFC AC/DC变换器为研究对象，展开了相关的理论分析和实验研究，为开关功率变换器的稳定、可靠运行提供技术解决方案。论文完成的主要工作以及取得的成果归类如下： ①在开关功率变换器的稳定性分析方法上，改进了传统的雅克比(Jacobian)矩阵的求解法，所得的通用性的结果可简化快变不稳定行为的分析，为后面的控制参数优化工作提供了一种理论手段。 ②结合峰值电流模式Boost PFC变换器，研究了斜坡补偿(SC，slopecompensation)控制效果及存在的问题。应用所提的Jacobian矩阵的求解法，导出斜坡补偿控制斜率的稳定工作范围，为控制参数选取提供了理论选择依据。所给的实验结果表明，斜坡补偿能够有效抑制系统的快变不稳定行为，但斜坡补偿存在补偿度问题,降低了稳态的电感电流峰值，从而引起过零处的电流畸变，造成原有Boost PFC变换器系统的功率因数恶化，，本部分研究工作阐明了传统斜坡补偿存在的问题及原因，也为后续动态斜坡补偿策略的探索提出了一种工程实际需求。 ③针对传统斜坡补偿存在过零畸变问题，本文提出了一种零扰动动态斜坡补偿控制策略，除了保留了原有SC的稳定控制优点外，同时改进其不足。分别结合峰值电流单环、电压电流双环控制Buck变换器以及峰值电流模式Boost PFC变换器为例，构建各自的零扰动动态补偿控制方程，利用Jacobian矩阵的改进求解法给出控制参数的理论工作范围，最后给出相关的仿真和实验验证。实验结果表明，零扰动动态斜坡补偿可以有效抑制系统存在的快变不稳定行为，同时解决了电流的过零畸变问题，有效提高系统的功率因数。
[Abstract]:Switching power converter set power tube nonlinear element and a storage element, its characteristic is piecewise linear, strong coupling nonlinear characteristics, not only will inject a large amount of harmonic to the power system, and when the system parameter changes, will become unstable rich, such as harmonic oscillation and low frequency oscillation. The existence of these unstable behavior. The performance caused by the switching power converter system deterioration. Therefore, the fast change of peak current mode switching power converter (such as harmonic instability behavior of dynamic slope compensation (DSC), dynamical slope compensation) control strategy, combined with the typical DC/DC Buck converter and Boost PFC AC/DC converter as the research object, carried out theoretical analysis and experimental research, for switching power converter is stable, reliable operation to provide technical solutions in this thesis. The main work completed and the results obtained are as follows:
The stability of switching power converter analysis method, improved Jacobi (Jacobian) method for solving matrix, the general result can simplify the analysis fast unstable behavior, provides a theoretical means for the following optimization of the control parameters.
With the combination of peak current mode Boost PFC converters, the slope compensation of (SC, slopecompensation) control effect and existing problems. Solving method of Jacobian matrix using the proposed the stable working range derived slope slope compensation control, as the control parameter selection provides a theoretical basis for the selection. The experimental results show that the slope fast compensation can effectively suppress the system unstable behavior, but there are problems of slope compensation compensation degree, reduce the peak inductor current steady state, which caused the distortion of the current zero, so the power factor is the original Boost PFC converter system deteriorates, the research results of this part illustrates the problems and reasons of traditional slope compensation. Put forward a project to explore the actual needs of the subsequent dynamic slope compensation strategy.
According to the traditional slope compensation has zero crossing distortion problem, this paper proposes a zero disturbance dynamic slope compensation control strategy, in addition to retaining the advantages of stable control of the original SC, while improving its shortcomings. Combined with the peak current of single loop, voltage and current double loop control Buck converter and the peak current mode Boost PFC converter an example, to build their own zero dynamic disturbance compensation control equation, using Jacobian matrix to improve the solving method is given control parameters of the theoretical scope of work, finally gives the simulation and experiment related validation. The experimental results show that the zero disturbance dynamic slope compensation can effectively suppress the system has fast varying unstable behavior, and solves the problem of zero distortion current too, effectively improve the power factor of the system.

【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】：TM46

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