基于LC吸收电路的耦合电感倍压单元高升压增益Boost变换器

High Voltage Gain Boost Converter Based on Coupled-Inductor Voltage-Doubler Cell and LC Snubber Circuit

提出一种基于LC吸收单元的耦合电感倍压单元高增益Boost变换器。在Boost变换器中引入耦合电感倍压单元,通过调节耦合电感变比,可实现Boost变换器的高升压增益特性。同时,引入LC吸收电路网络,回收了漏感能量,抑制了开关管两端的电压尖峰,从而可通过选取低导通电阻、低电压等级的MOSFET,以降低变换器成本和开关管的导通损耗,提高变换器的效率。提出的变换器消除了耦合电感的二次侧漏感与输出二极管寄生电容带来的二极管电压尖峰振荡问题,从而减小了二极管的电压应力,进一步改善了变换器的效率。此外,采用LC吸收电路的高增益变换器具有输入电流连续、易实现高升压增益特性的优点,适用于新能源发电领域。详细分析了该变换器的工作原理及工作特性,给出了关键参数的设计原则。最后,通过实验结果验证了理论分析的正确性。

A high voltage gain converter with coupled-inductor voltage-doubler cell and non-dissipated LC snubber circuit is presented in this paper. A coupled-inductor voltage-doubler cell is utilized to achieve high step-up voltage gain of boost converter. Meanwhile, non-dissipated LC snubber circuit is used to recycle leakage inductance energy and suppress voltage spike stress of the power switch. Therefore, a MOSFET that has low switch-on resistance and low voltage level can be employed, to reduce the conduction loss and improve cost and efficiency of converter. Furthermore, the voltage-double cell can eliminate the voltage oscillation of the output diode, so reduce the voltage stress of output diode. In addition, the proposed converter with LC snubber circuit has continuous input current and high boost ratio. Therefore, it is suitable for fuel cell or photovoltaic application. Steady state analysis and the operating characteristics of the converter are discussed in detail. Finally, experimental results verify the proposed converter.