大功率同步整流的均流及环流技术

Current Sharing and Circulation Technology of High-Power Synchronous Rectification

分析了3种用于同步整流的控制方式,并通过能耗计算对比选择出最优控制方式.为克服单个器件及单个电路输出功率的局限性,对大功率场合多管并联的均流问题进行了研究,确定了影响并联均流的主要敏感参数,并给出了优化均流的解决方法.探讨了多同步整流电路并联环流的产生机理,并给出了防止环流的占空比协调控制方法.实验结果验证了理论分析的准确性,采用文中方法可成功实现同步整流的大功率输出.

In this paper,first,an optimal control mode is selected from three control modes for synchronous rectification through energy consumption calculation,and the current sharing problem of the multi-tube paralleling in high-power synchronous rectification is investigated to overcome the output power limitation of single device and single circuit. Then,the main sensitive parameters affecting the parallel current sharing are determined,and a solution to the optimization of current sharing is presented. Moreover,the generation mechanism of the circulation caused by multi-circuit parallel connection is discussed,and a coordination control method of the duty cycle for preventing the circulation is finally presented. Experimental results show that the theoretical analysis is correct and that the proposed method helps to successfully implement the high-power output of synchronous rectification.