电流源型LCL谐振式变换器的研究

该文主要研究在一定条件下可实现输出恒流特性的LCL谐振变换器及其优化设计。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。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。最后基于所优化设计的品质因数值设计一台额定功率为80 W的LCL谐振变换器样机，实验结果验证变换器的恒流性能及品质因数值选择的合理性。

Investigation on LCL Resonant Converter as Current Source

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, and the 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. An 80 W LCL resonant converter was designed with a reasonable quality factor. The experimental results verified that the LCL resonant converter can work as a constant current source in certain condition and the design method of the quality factor is rational.