With　constructions　of　demonstrative　microgrids,　the　realistic　optimal　economic　dispatch　and　energy　management　system　are　required　eagerly.　However,　most　current　works　usually　give　some　simplifications　on　the　modeling　of　microgrids.　This　paper　presents　an　optimal　day-ahead　scheduling　model　for　a　microgrid　system　with　photovoltaic　cells,　wind　turbine　units,　diesel　generators　and　battery　storage　systems.　The　power　flow　constraints　are　introduced　into　the　scheduling　model　in　order　to　show　some　necessary　properties　in　the　low　voltage　distribution　network　of　microgrids.　Besides　a　hybrid　harmony　search　algorithm　with　differential　evolution　(HSDE)　approach　to　the　optimization　problem　is　proposed.　Some　improvements　such　as　the　dynamic　F　and　CR,　the　improved　mutation,　the　additional　competition　and　the　discrete　difference　operation　have　been　integrated　into　the　proposed　algorithm　in　order　to　obtain　the　competitive　results　efficiently.　The　numerical　results　for　several　test　microgrids　adopting　the　IEEE　9-bus,　IEEE　39-bus　and　IEEE　57-bus　systems　to　represent　their　transmission　networks　are　employed　to　show　the　effectiveness　and　validity　of　the　proposed　model　and　algorithm.　Not　only　the　normal　operation　mode　but　also　some　typical　fault　modes　are　used　to　verify　the　proposed　approach　and　the　simulations　show　the　competitiveness　of　the　HSDE　algorithm.　(C)　2016　Elsevier　Ltd.　All　rights　reserved.