一种高增益零输入电流纹波Sepic变换器

A High-gain Zero-input Current Ripple Sepic Converter

针对传统变换器电压增益低,开关处于硬状态工作,输入纹波大等缺点,提出一种高增益零输入电流纹波拓扑结构。将无源纹波单元接入到传统Sepic变换器的输入端,通过耦合电感与电感电容串联组合,保留输入电流连续的特点,同时实现输入电流零纹波效果,且零纹波实现与占空比大小无关,从而延长光伏组件中电池使用寿命,电路可靠性高。通过倍压单元结构和无源钳位吸收电路组合,开关管电压应力降低,便于采用低耐压开关器件,损耗降低。在零输入电流纹波变换器等效模型的基础上,分析变换器的工作原理,对比不同变换器的工作性能。最后搭建一台100 W的试验样机,验证了理论分析的正确性和电路的可行性。

In view of the low voltage gain,hard state switch operation and large input ripple,a high-gain zero-input current ripple topology is proposed.The passive ripple unit is connected to the input end of the traditional Sepic converter,by coupling inductance and inductor capacitor series combination,retain the characteristics of continuous input current,while realizing the input current zero ripple effect,and zero ripple realization is independent of the duty cycle,so as to extend the service life of cells in photovoltaic modules,circuit reliability is high.Through the combination of double voltage unit structure and passive clamp absorption circuit,the voltage stress of the switch tube is reduced,which is convenient to use low voltage resistant switching devices,and the loss is reduced.On the basis of the equivalent model of the zero-input current ripple converter,the working principle of the converter is analyzed,and the working performance of the different converters are compared.Finally,a 100 W test prototype is built to verify the correctness of the theoretical analysis and the feasibility of the circuit.