宽占空比交错控制的三绕组耦合电感DC/DC变换器

An extended duty ratio DC/DC converter with three-winding coupled inductor

文章提出了一种新型交错连接三绕组耦合电感高增益DC/DC变换器。该变换器中,首先每个耦合电感的第二绕组分别与一个电容相串联构成准倍压单元,再与其原边绕组和主开关管S共同形成一相升压电路;其次每个耦合电感的第三绕组与该相开关管的钳位电容一起为另一相的准倍压单元进行充电,从而将两相电路进行交叉耦合;然后将耦合电感的原边进行交错并联。上述结构有以下优点:该变换器可以工作在较宽的占空比变化范围(0<D<1);每相电压和电流具有自动均分的功能;既能提高变换器的电压增益,又能降低功率器件的电压应力,同时具有灵活的高增益调整能力。笔者详细分析了所提变换器的工作原理,最后给出了实验结果以验证理论分析的正确性。

In this paper,an interleaved high step-up DC-DC converter with winding-cross-coupled inductors is presented.Firstly,the second winding of each coupled inductor is connected with a capacitor,which composes a quasi voltage multiplier unit（QVMU）.Then,a boost circuit consists of the QVMU,the primary winding and the main switch.Moreover,the QVMU can be charged through the clamp capacitor and the third winding of the other phase coupled inductor.Thus,two phases can be cross-coupled.Furthermore,the primary currents of two coupled inductors are interleaved in parallel at input.There are many advantages of the above-mentioned structure.Firstly,the proposed converter can be operated in the duty cycle of the entire range of variation and the expression of the voltage gain can be consistent across the range of the duty cycle.Secondly,the output voltage and input current of each phase can be automatically regulated to be equally distributed.Thirdly,the proposed converter can achieve a high step-up voltageconversion and the voltage stress on the power devices can be reduced.Lastly,a high step-up gain can be flexibly adjusted.The operating principle of the proposed converter is analyzed.In order to verify the theoretical analysis,an experimental prototype is built.