基于分裂-叠加结构的部分功率主动调控型准单级直流变换方法

Quasi Single-stage DC-DC Conversion Method with Partial PowerActive Regulation Based on Split-sigma Structure

针对“直流变压器级联PWM变换器”两级式架构中各级变换器均需处理全部负载功率、多级变换效率低的问题,提出了基于分裂-叠加架构的部分功率主动调控型准单级直流变换方法。通过将直流变压器输出分裂为两个端口,使得其中一个端口的功率无需经后级PWM变换器处理而直接传输至负载,等效实现了准单级功率变换,且有效降低了PWM变换器的功率容量和损耗,提高了系统效率。详细分析了分裂-叠加式架构的原理和电路实现方法,深入研究了系统输出电压调节的原理和特性。以其中一个电路为例,详细分析了工作原理、电压调节特性和关键参数设计方法,并通过实验结果验证了所提方案的有效性和正确性。

Aimed at the low conversion efficiency and all the load power that needs to be processed by converters at different stages in the two-stage architecture of a DC transformer cascaded PWM converter,a quasi single-stage DC-DC conversion method with partial power active regulation based on a split-sigma structure is proposed.By splitting the output port of the DC transformer into two ports,the power of one port is directly transmitted to load without being pro-cessed by the back-stage PWM converter,thus realizing the quasi single-stage power conversion equivalently.In addi-tion,the power capacity and loss of the PWM converter are effectively reduced,and the system efficiency is improved.The principle and circuit implementation method for the split-sigma structure are analyzed in detail,and the principle and characteristics of system output voltage regulation are also studied.One of the circuits is taken as an example,and its working principle,voltage regulation characteristics and design method for key parameters are analyzed.Finally,experimental results verified the effectiveness and correctness of the proposed scheme.