毕业设计电流源型LCL谐振式变换器的详解.docVIP

摘 要 谐振变换器可通过谐振元件的谐振实现开关管的零电压开通或零电流关断，具有较高的效率。由于开关损耗小，变换器可工作在较高频率下，它的体积小，功率密度大。谐振变换器已在DC-DC 变换器中得到了广泛应用， 并在不断地发展之中。 该毕业设计论文主要研究在一定条件下可实现输出恒流特性的LCL 谐振变换器及其品质因数优化设计，最后设计出基本控制电路。阐述 LCL 谐振变换器工作于恒流源模式下的工作过程及其实现恒流特性的原理。仿真主电路波形，在一定频率下，电路能保持横流时负载可以变化的范围，为分析变换器工作于非谐振频率时的特性，给出不同品质因数下，开关频率变化时，变换器的电流增益特性曲线及谐振电感电流有效值、电容电压有效值的关系曲线，并分析得到品质因数的选择对变换器的恒流特性及谐振元件电压电流应力的影响，提出基于品质因数的变换器优化设计方法。LCL谐振式变换器在品质因数等于多少时，工作状况较好。最后，通过对主电路的理解，设计出控制电路。 关键词　LCL谐振；恒流源；品质因数；控制电路 Abstract Resonant converter available through resonant element of resonance of the switching pipe ZVS or zero current showdown , relatively efficient. Because switching losses, converter to work at higher frequencies, its small size, power density. Resonant converter has been in the DC-DC converter extensively。 A LCL resonant converter behaving as a current source in certain condition and its optimization design method was investigated in this paper. The working process of this topology as a constant current source was analyzed and the principle why this topology could work as a constant current power-supply was presented. To investigate the converter performance when the converter does not work under resonant frequency, the converter current gains versus switching frequency under different quality factors were presented, andthe relations between resonant inductor currents or resonant capacitor voltage with switching frequency under different quality factors were presented. The influences of quality factor on constant-current characteristic and current or voltage stress of the resonant components were analyzed. Then the optimization design method of the converter based on quality factor was proposed. LCL resonant converter in quality factor is equal to the number, the better working conditions. Finally, through the understanding of the primary circuit to make the control circuit. Keywords　LCL resonant,constant current source,quality factor,control circuit  目 录 摘 要 I Abstract II 第1章 绪论 1 1.1 课题背景 1 1.1