《毕业论文_脉宽调制移相全桥变换器设计》由会员分享，可在线阅读，更多相关《毕业论文_脉宽调制移相全桥变换器设计（72页珍藏版）》请在金锄头文库上搜索。
1、燕山大学本科毕业设计（论文）I本科毕业设计（论文）脉宽调制移相全桥变换器设计燕山大学本科毕业设计（论文）I摘 要本论文研究了一种新型的 ZVZCS PWM DC/DC 全桥变换器。该变换器以全桥变换器为主电路，来实现超前桥臂的零电压开关以及滞后桥臂的零电流开关。控制电路以 UC3875 为主要控制芯片，来实现移相控制方式，并最终达到软开关目的。该变换器的输入电压为 450V 直流,输出电压为24V 直流。本文通过对 ZVZCS 移相全桥 DC/DC 变换器的分析研究，改进了传统的主电路拓扑，优化了电路系统参数，完善了电路控制方案，通过理论分析与模拟仿真，设计并制作了改变换器的试验样机，并验证了
2、其工作原理和性能特点。论文以全桥变换器作为主电路拓扑。全桥电路拓扑结构简单，控制容易，广泛应用于高质量要求及大功率场合。众所周知，功率密度的提高意味着开关频率的提高，随之而来的是开关管的损耗，这便要求在工作工程中能够实现开关管的软开关。论文在传统通过在变压器副边加入一个电容Cc和两个二极管 Dc，Dh组成的简单辅助电路，使得超前桥臂实现了 ZVS,滞后桥臂实现了 ZCS，而且对副边整流桥进行钳位，降低了开关管的开关损耗和电路中的环流损耗，从而大大提高了变换器的工作效率。为了使该变换器具有良好的稳态性能，变换器采用电压闭环控制。并通过 UC3875 芯片实现了输出过电流保护和输入欠电压保护。论文
3、通过理论分析，设计了该变换器的主电路拓扑，控制电路，保护电路及反馈电路的各项参数，最终对该变换器通过 PSIM 软件进行模拟仿真，并给出了实验结果。关键词关键词 DC/DC 变换器；移相全桥；软开关；谐振；AbstractIIAbstractThis paper studied a new kind of ZVZCS PWM DC/DC full bridge converter. The converter is given priority to with full bridge converter circuit, to realize the advanced bridge arm z
4、ero voltage switch and zero current switch lag bridge arm. Control circuit UC3875 as the main control chip, to achieve phase-shifting control mode, and ultimately achieve soft switch. The converter input voltage is 450 VDC, the output voltage is 24 VDC. This article through to the ZVZCS phase-shift
5、full bridge DC/DC converter of analysis and research, improved the traditional main circuit topology, circuit system parameter was optimized and improved the circuit control system, through the theoretical analysis and simulation, the design and construction of the converter instead of experimental
6、prototype, and verify its working principle and performance characteristics.Papers to the full bridge converter as the main circuit topology. The whole bridge circuit topology structure is simple, easy control, are widely used in high quality requirement and high power occasion. As is known to all,
7、the improvement of power density means the improvement of switching frequency, followed by the wastage of the switch tube, this requirement can be achieved in the engineering work of the switch tube soft switch. Papers in traditional by joining at the edge of the transformer, vice a Dc capacitor Cc
8、and two diodes, Dh consisting of a simple auxiliary circuit, makes the bridge arm realizes ZVS in advance, the lag bridge arm realized ZCS, and vice side of rectifier bridge for clamping, reduce the loss of the switch of the switch tube and circulation loss in the circuit, thus greatly improving the
9、 work efficiency of the converterIn order to make the converter have a good steady-state performance, voltage converter adopts closed loop control. And through U3875 chip to achieve the output over current protection and input under voltage protection .燕山大学本科毕业设计（论文）IIIBased on theoretical analysis,
10、 this paper designs the main circuit of the converter topology, control circuit, protection circuit and feedback circuit parameters, finally using the psim simulation to the converter, and gave the experimental results.Key words DC/DC converter; Phase-shift full bridge; zero-voltage switching; ZCS;
11、Soft switch; Resonance; UC3875 chipIV目录摘要.III Abstract.III第 1 章 绪论.3 1.1 课题背景及意义 .3 1.2 国内外 DC/DC 变换器技术的发展历程 .3 1.3 课题方案选择与设计 .3 1.3.1 主电路拓扑的选择 .3 1.3.2 控制方式的选择 .3 1.4 课题的主要研究工作 .3 第 2 章 移相全桥 ZVZCS 变换器.3 2.1 常规全桥电路工作分析 .3 2.2 ZVZCS 变换器工作特点与变换器性能分析.3 2.2.1 主电路拓扑 .3 2.2.2 工作状态分析 .3 2.3 变换器软开关实现的条件 .3 第 3 章 电路参数设计.3 3.1 主电路拓扑设计 .3 3.1.1 逆变全桥部分 .
