基于DSP的滑模控制DC-DC变换器的设计

发布时间：2018-12-18 14:43

【摘要】：DC-DC变换器广泛应用到通信、计算机、家用电子产品和航天等领域中,随着科技的发展,一些电子器件对电源的要求越来越高,如家用电子产品中需要用到电压稳定、内阻极小、动态性能优良的便携式电源。所以,研究高性能的DC-DC变换器已经成为现代电源研究中的主要方向。本文在分析了DC-DC变换器的几种常用数学模型的基础上,将滑模变结构控制理论应用于DC-DC变换器设计中,设计了一台基于DSP的滑模控制DC-DC变换器,主要工作如下：首先,介绍了DC-DC变换器常用的线性控制策略和非线性控制策略的优点和不足,以及DC-DC变换器的模拟和数字控制技术。以DC-DC变换器中的Buck变换器、Boost变换器、Buck-Boost变换器为例,分析了它们拓扑结构的特点和几种常用建模方法,以及使用这些方法在设计DC-DC变换器时的一些局限。其次,分析了滑模控制理论,将滑模控制理论应用于Buck变换器,设计了一种使用固定频率PWM波的滑模控制方法,该方法不仅降低了功率开关的频率,而且解决了开关的转换速度对滑模控制器性能的影响。整个系统包括主功率回路、电感电流检测电路、电容电流检测电路、DSP控制电路。最后,完成整个系统的测试。实验结果表明,本文使用的基于PWM技术的变结构滑模控制方法,很好的解决了开关切换速度对滑模变结构控制的影响。在系统内部参数变化时具有很好的鲁棒性,且控制精度高,动态响应速度快。
[Abstract]:DC-DC converters are widely used in the fields of communication, computer, household electronics and spaceflight. With the development of science and technology, some electronic devices require more and more high power supply, such as voltage stability in household electronic products. Portable power supply with minimal internal resistance and excellent dynamic performance. Therefore, the research of high performance DC-DC converter has become the main research direction of modern power supply. Based on the analysis of several common mathematical models of DC-DC converter, the sliding mode variable structure control theory is applied to the design of DC-DC converter. A sliding mode control DC-DC converter based on DSP is designed. The main work is as follows: firstly, the advantages and disadvantages of linear and nonlinear control strategies used in DC-DC converters are introduced, as well as the analog and digital control techniques of DC-DC converters. Taking Buck converter, Boost converter and Buck-Boost converter in DC-DC converter as examples, the characteristics of their topological structure and several common modeling methods are analyzed, and some limitations of using these methods in designing DC-DC converter are analyzed. Secondly, the sliding mode control theory is analyzed, and the sliding mode control theory is applied to Buck converter. A sliding mode control method using fixed frequency PWM wave is designed, which not only reduces the frequency of power switch, but also reduces the frequency of power switch. Moreover, the effect of switching speed on the performance of sliding mode controller is solved. The whole system includes main power circuit, inductance current detection circuit, capacitive current detection circuit and DSP control circuit. Finally, the test of the whole system is completed. The experimental results show that the variable structure sliding mode control method based on PWM technology can solve the effect of switching speed on sliding mode variable structure control. It has good robustness, high control precision and fast dynamic response speed when the system parameters change.
【学位授予单位】：华中师范大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM46

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