同步整流技术采用低导通电阻的MOS管代替导通压降相对较大的快恢复二极管或肖特基二极管，大大减小了输出整流损耗，效率相对提高。但由于MOS管的无法正常驱动及其体内二极管的导通等问题，影响效率的进一步提高。 本文对目前常用的几种驱动电路拓扑结构进行了详细讨论和分析，并深入的研究基于推挽电路的栅极电荷保持驱动方式。 栅极电荷保持驱动技术是利用MOS管寄生的栅极电容存储和释放电荷，实现了在低电压输出和死区时间内均能有效地驱动MOS管，从而解决了体二极管的反向导通和模块并联产生的环流等问题，达到了减小输出整流损耗的目的。本文在电源主电路方面选用推挽电路，其输出整流方面采用倍流整流方式，可以拓宽电源的应用范围和降低变压器的制造难度，实现高效率的电源。 为保障有效的驱动电压，不出现欠驱动和过驱动的现象，此方案对变压器的耦合性提出较高的要求。本文通过对驱动电路理论分析和仿真实验，给出了实现高耦合性的变压器的设计方案，同时对输出多路低电压大电流的电路拓扑和参数设计进行了研究。 本文通过一台实验样机的测试数据各试验波形，证实了理论分析的可行性和优越性。

In the way of MOS taking place of the Fast recovery diode and the Schottky barrier diode, it can cut down on-resistance and reduce the rectification loss. For the disadvantages of the insufficient driving of the low side switch and the body diode conduction and so on, it can’t improve the efficiency farther more. The paper discusses and analyzes several general schemes about synchronous rectification in detail, and studies a gate charge retention synchronous rectification based on the push-pull circuit deeply. The current flows through both parasitic capacitances, charging one while discharges the other in this scheme. It resolves the questions about the body diode conduction and circumfluence in paralleled converters, and increases the efficiency. Based on the push-pull topology, using double-current rectification in secondary part, it can wide the appliance scope, decrease the difficulty of manufacturing transformers and achieve high efficiency converters. High quality to the coupling between all the windings, it can prevent the abnormal phenomenon on gate-source, not a negative voltage, but a positive voltage. Through theoretical analyses and simulations, the paper provides the scheme of keeping good-coupling to the transformer. It also discusses the topology of multi-output and the design of parameters. The theoretical analysis is verified by the experimental sample, data and waveforms.