适用于户用直流微网的三端口DC/DC变换器拓扑研究

Research on the topology of Three-port DC/DC converter intended for household DC Micro-grid

为解决分布式电源的间歇性,微网被广泛研究和应用。相较于交流微网,直流微网结构简单,有利于提高电网的运行水平。在直流微网中,分布式电源、储能系统和负载往往都通过独立DC/DC接入直流母线。为使直流微网的结构更加紧凑、简单,提出一种适用于户用三端口零电流反激式DC/DC变换器,可以有效地实现不同电压等级端口之间的能量互通。通过拓扑分析和仿真研究,验证拓扑的合理性和有效性,其能够降低开关管关断时两端电压幅值,同时实现开关管的零电流开关,从而降低开关管的开关损耗,提高直流微网的可靠性。

In order to solve the intermittent nature of distributed power,micro-grids are widely studied and applied.Compared with the AC micro-grid,the DC micro grid has a simple structure,which is conducive to improving the operating level of the grid.In DC micro-grids,distributed power supplies,energy storage devices,and loads are often connected to the DC bus through independent DC/DC.In order to make the structure of the DC micro-grid more compact and simple,a three-port zero-current flyback DC/DC converter suitable for the household DC micro-grid is proposed,which can effectively realize the energy interoperability between ports of different voltage levels.Through its topology analysis and simulation research,the rationality and effectiveness of the proposed topology are verified.It can reduce the voltage amplitude at both ends when the switch is turned off,and realize the zero current turn-on and turn-off of the switch tube,thus reducing the switching loss of the switch tube and improves the operating efficiency of the DC micro grid.