Energy gateway, household appliance, direct-current micro-grid system and energy management method therefor

An energy gateway, a household appliance, a direct-current micro-grid system and an energy management method therefor. The energy gateway comprises: a direct-current input end (1) for being connected to a direct-current output end of an external solar power generation apparatus (2). The energy gateway further comprises a first direct-current output end and/or a second direct-current output end for supplying power to an external direct-current electrical appliance (4), wherein the first direct-current output end is directly connected to the direct-current input end, and the second direct-current output end is connected to the direct-current input end via a direct-current voltage transformation apparatus (5). The energy gateway, the household appliance and the direct-current micro-grid system make a grid-connected inverter dispensable, reduce device investment and electric energy conversion links, and improve the utilization efficiency of new energy photovoltaic power generation. Furthermore, since the household appliance directly supplies power with a direct current, an internal rectification module can be removed, so as to reduce device investment and electric energy conversion loss, and eliminate multiple problems; for example, electric energy quality being influenced by harmonic pollution brought by the household appliance to a power grid.