【作者】 马忠科；

【导师】 刘文生；

【作者基本信息】 大连交通大学 ， 交通信息工程及控制， 2007， 硕士

【摘要】 随着经济的发展和科学技术的进步，节约能源、保护环境已被社会各界所重视。高频开关电源技术发展所带来的“20kHz电源技术革命”，使其在许多工业电源领域得到了广泛的应用和迅速的发展。然而开关电源的大量使用，尤其是大功率开关电源的应用，给电网带来了电磁污染的问题，制造了大量的高次谐波和电磁干扰EMI，这一点是与近年来电力电子学界提出的“绿色电源”涵义相违背的。本课题以逆变器辅助开关电源作为研究对象，分析了造成上述问题的主要原因，其一是开关电源的输入端采用二极管整流，后接较大的滤波电容，导致输入电流为一很窄的脉冲波，其中含有丰富的谐波分量；其二是由于电源采用了硬开关的开关工作模式，这使得在高频的开关速度下，电路中的di／dt和du／dt增大，从而导致了对周围环境的电磁干扰的增大。减少开关电源对环境的电磁污染，一是进行功率因数校正(PFC)；二是采用软开关的开关工作模式，软开关使电源在工作过程中的di／dt和du／dt较硬开关时大大降低，从而使EMI的问题得以解决。本文正是在上述分析的基础上，着眼于原开关电源的EMI和主要损耗，在原有电路的基础上做了一些改进。主要包括：1、功率因数校正(PFC)方面，采用无源PFC技术中的一种——逐流技术，进一步减少了开关电源的对电网的谐波污染；2、开关模式方面，采用软开关中的有源钳位软开关代替原来的硬开关，很好地解决硬开关模式下的种种弊端。本文对每个改进环节都进行了具体的仿真分析和实验，验证了改进思路的可行性及其对减少环境污染，提高电源效率的有效性。更多还原

【Abstract】 Along with the development of economy and the progress of science and technology, saving the energy and protecting the environment have been pay more attention to by all circles of the society. "The technological revolution of 20kHz power supply" brought by the development of the high frequency switching power supply technology, makes it widespread application and rapid development in many industries power supply domain. However the massive use of switching power supply, especially the high power switching power supply, has brought the electromagnetism pollution to power system, has made a large amount higher harmonics and electronmagetic interference (EMI), this point violates the connotation of "the green power source" which was proposed by the power electronics circles recently.The topic takes the auxiliary switching power supply of inverter as the research object, the main reason of making above problems is discussed, one is the nonlinear rectifier with a bulky capacitor in the input stage of switching power supply, which leads to a narrow pulse and rich harmonics; the other is the hard-switching work mode, this makes di/dt and du/dt in circuit increased under the high frequency switching-speed, accordingly makes the EMI to environment increase. To decrease the switching power supply electromagnetism pollution to environment, one way is carrying on the power factor correction (PFC); the other way is using the soft-switching work mode, the soft-switching compared with hard-switching makes di/dt and du/dt greatly reduce during the work progress, thus it enables EMI to be solved.Basing on the above analysis and focusing on the EMI and main lose of switching power supply, the thesis has made some improvements based on the original electric circuit. Mainly includes: 1, the aspect of power factor correction (PFC), using one kind of the passive PFCtechnologies-chase-flows technology, it reduce "the pollution" to power system; 2, theaspect of switching mode, using the active clamp soft -switching in the soft-switching to replace the original hard-switching solves kinds of disadvantage under hard-switching mode well.The thesis gives concrete simulation analysis and experiment to every improvement step, the conclusion verified the feasibility of the improved thoughts and the validity of reducing the environmental pollution and enhancing the power efficiency of it.更多还原