交流-直流转换器高转换效率控制方法

High transfer efficiency control method for AC/DC

为了提升工作在不连续模式下反激式交流-直流转换器的转换效率,研究和分析了一个开关周期中系统在各状态时的功率损耗机制,在此基础上推导与建立了反激变换器系统功率级损耗模型.通过对该模型进行MATLAB分析和仿真,得出了各关键系统参数的损耗曲线及其对系统总损耗的影响。基于对损耗因子的分析,提出了一种高效的恒压控制策略,该策略中各参数控制曲线均基于MATLAB建模分析.文中所提恒压控制策略采用0.35μm/700V/BCD(Bipolar-CMOS-DMOS)工艺实现,仿真与实测结果均验证了其具有良好的负载响应能力.通过对流片后的芯片进行测试,其5W下的效率可达83%,超出最新DoE.6能效标准,实现了高效能转换.

To improve the transfer efficiency of the AC/DC converter system working in the DCM （Discontinuous Conduction Mode） mode, the power consumption mechanism of the system in different states in one switching period is studied and analyzed, on the basis of which the power stage model is constructed. By MATLAB simulation as well as analysis, the power loss curves of key factors are obtained. On the basis of the analysis, a high efficient constant voltage control method is proposed. The constant voltage control strategy is realized by a 0.35 μm/ 700 V/ BCD （ Bipolar -CMOS -DMOS） process, and simulation and experiment show that the strategy has an excellent load transient response. The transfer efficiency when the power consumption is 5W can reach a level as high as 83%, which exceeds the newest DOE. 6 standard, thus realizing the high transfer efficiency.