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本科生毕业设计（论文）

隔爆兼本安题目： BUCK 变换器设计

电气工程自动化 08-3 班

二〇一一年六月

毕业论文题目： 隔爆兼本安BUCK变换器的设计

毕业论文专题题目：

毕业论文主要内容和要求： 1.了解本质安全理论及意义 2.掌握BUCK电路的工作原理 3.控制芯片的选择及使用 4.本质安全变换器的设计

5.本质安全变换器输出保护电路 6.转换器的仿真

7.完成与毕业设计内容相关的英文翻译（近三年的文献），不少于字

院长签字： 指导教师签字：

3000汉

摘 要

开关电源具有高效率、体积小、性能可靠、电路简单，等优点，BUCK变换器是开关电源一种基本拓扑结构，输出电压总是低于它的输入电压，在现代科学研究和工业生产中得到了越来越广泛的应用。

工作在含有爆炸性混合物环境的电子设备必须满足防爆的要求，本质安全型是最佳的防爆形式，本质安全变换器是本质安全电源的核心，因此研究本质安全开关变换器是研究本质安全开关电源的基础。

本文首先介绍了本质安全电路理论、背景及发展史和电路放电的三种形式，并对BUCK变换器的原理及滤波电感的连续、断续及临界三种状态进行分析说明。本文采用PWM电压型控制芯片UC3573进行控制，它可以使开关电源的元器件数量大幅地减少，提高开关电源的性能，使电路简单等优点 ,并对UC3573芯片的原理和各个管脚的功能做了详细的介绍。对本质安全BUCK变换器的保护原理进行分析，并给出输入、输出过压保护电路和输出过流、短路保护电路及原理分析。

最后进行仿真和试验研究，给出了相关实验波形并进行了分析，结果验证了设计的可行性。

关键词： 开关电源； 本质安全； BUCK变换器； UC3573

Abstract

Switching power supply with high efficiency, small size, reliable performance, simple circuit, etc., BUCK converter is a basic topology switching power supply, the output voltage is always lower than its input voltage, in modern scientific research and industrial production is more and more widely used.

Work environment in the presence of an explosive mixture of electronic equipment must meet the requirements of explosion-proof, intrinsically safe is the best form of proof, intrinsically safe intrinsically safe power supply converter is the core, the study of intrinsically safe switching converter is intrinsically safe switch power base.

This paper introduces intrinsically is safe circuit theory, history and background and three forms of discharge circuit, and the BUCK converter and the filter inductance principle of continuous, intermittent, and that the critical analysis of three states. In this paper, the control chip is UC3573 PWM voltage control, switching power supply which can reduce substantially the number of components is to improve the performance of switching power supply, so that the advantages of simple circuit, and the UC3573 chip principle and function of each pin is detailed. BUCK converter on the nature of the protection of the safety analysis of the principle, and give input, output over-voltage protection circuit and output over-current, short circuit protection circuit and principle.

Finally, simulation and experimental is researched, experimental waveforms are given and analyzed, the results verify the feasibility of the design.

Keywords: switching power supply; intrinsically safe; BUCK converter; UC3573