(毕业论文)恒流脉冲波的设计.doc

摘　要 　　随着电力电子技术的飞速发展,各种电子设备对于电源的性能、重量、体积、效率提出了更高的要求,目前开关电源的控制方式多釆用电压控制型技术。电压控制型存在响应速度慢等缺点。针对电压控制型电路的缺点,最近十几年发展起来了电流控制型技术,它具有很好的快速响应，因此,对其进行研究设计具有十分重要的意义。 本论文是在研究分析了开关电源的基本原理以及UC3846芯片与TLP250芯片的功能与特性的基础上，设计了一种基于UC3846的电流型全桥拓扑结构的恒流高频开关电源。主要进行了输入整流电容滤波、高频变压器的设计、驱动电路和控制电路等主要元器件和电路模块的选型与参数设计。论文所设计的开关电源的输入为市电220V交流，输出电压为24V，电流为5A，开关频率为90khz。 　　最后基于原理分析与计算，搭建全桥拓扑实验平台。实验结果表明：输入整流滤波电压符合理论分析，控制电路的调试也基本符合要求。 关键词: PWM控制 ； 全桥电路 ； 高频变压器 ； UC3846  Abstract With the rapid development of power electronics technology, various kinds of electronic equipment for the performance of the power, weight, volume and efficiency put forward higher request, the control mode of switch power supply more bright type with voltage control technology. Voltage control type shortcomings slow response speed and so on. For voltage control circuit fault type, type the current control technology developed in recent ten years, it has the very good quick response, therefore, to study design has the very vital significance. This paper is lie on the research and analysis of the full bridge topology of switch power supply principle , UC3846 and TLP250 chip on the basis of the function and characteristics. Designed a current mode based on UC3846 full bridge topology structure of high frequency switching power supply with constant current. It contains input rectifier capacitance filter,high-frequency transformer design,drive circuit, control circuit of the main components and circuit module selection and parameter design. The paper design of switch power supply input from the mains AC 220 V, output voltage is 24 V, current is 5 A, the switching frequency of 90 khz. The last it based on the principle analysis and calculation, build full bridge topology experiment platform. Experimental results show that the input rectifier filter voltage accord with theoretical analysis, the control circuit of the PWM pul