DC/DC数控电源中降低输出纹波的研究

【作者】 马杰；

【导师】 吕征宇；

【作者基本信息】 浙江大学 ， 电力电子， 2003， 硕士

【摘要】 开关电源技术近年来发展迅速，高性能精密电源的社会需求也越来越多。对于高性能的开关精密电源来说，输出纹波是项很关键的参数。论文系统地分析了开关电源输出纹波的成因，提出了抑制措施，并得到实验验证。 论文首先介绍了一个具体精密开关电源的功能要求，并在此基础上给出了系统的总体框架和各部分电路的几种不同的设计方案。然后就如何减小纹波对输出的影响考虑，从系统方面和各级电路部分进行了细致理论分析，并提出了具体的解决方案。 论文从电源的系统结构与控制方面提出了比较新颖的三级级联和两级联动的纹波抑制措施：三级级联方案可以有效地降低输出低频纹波；两级联动方案则可以在低幅值输出时保证较低的输出纹波。论文就各级电路对输出纹波的影响作了一定深度的分析，采用的技术和控制方案有：采用了抑制输出二极管反向恢复的开关软化方案的功率因数校正级；采用了带电流环控制的倍流整流零电压移相全桥电路方案的隔离DC／DC级；采用了两级输出滤波方案和开关软化方案的精密输出级。 本文还提出了两个模块多重并联以减小输出纹波的方案，并就电源系统中的一些关键参数作了优化分析。 最后，根据所提出的设计方案制作了一台试验样机。实验结果表明，所提出的设计方案对于降低纹波效果明显，切实可行。更多还原

【Abstract】 The requirement of high performance and precision power supply is greatly increased with the development of switching power supply technology. The output ripple is a very important parameter of switching power supply. In this dissertation, some research works have been done to reduce the amplitude of output voltage ripple to be accepted degree.At the begin of the dissertation, some technical requirements of a digital controlled precision power DC/DC supply are introduced Based on these requirements, the method of ripple suppression is analyzed in detail, and the outline of this system and some optional schemes of main circuits are also given.Then some new schemes are proposed in different aspects of the power supply in order to decrease the amplitude of output voltage ripple. The novel schemes of three stages in series and double-stage linkage are introduced. The scheme of three stages in series can alleviate the low frequency ripple effectively and the double-stage linkage scheme has lower output ripple when lower voltage output is needed. Some advanced switching power supply technologies are also used in three different stage: a scheme to alleviate the rectifier reverse-recovery problem is usedin the power factor correction circuit stage, zero-voltage phased-shifted full bridge circuit with a current doubler rectifier is applied in the DC/DC isolated stage, and a two stage filters and the technology of alleviation the reverse-recovery problem are adopted to the precise output stage.In this dissertation, the plan of two power blocks’ parallel connection with the interleaved control method to reduce the ripple is suggested and some important parameters in the power supply system is also analyzed and optimized.Finally, a experimental power supply is made based on these schemes. The amplitude of the output voltage ripple satisfies the technical requirement .The analysis and proposal schemes are verified by circuit experiment.更多还原