Energy management system（EMS），known as the brain of power grid，utilizes information flow to control energy flow so as to keep power grid operation efficient and secure.Conventionally，the EMS is a centralized one with both information collecting and decision-making centralized.This architecture is facing a serious challenge in mass information collecting and faster decision，especially in smart grid environment.A new concept of distributed autonomy and centralized synergy is proposed and the EMS family covering all sections of smart grids（e.g.source，grid and demand）is concretized.Both commonness and individuality of these EMS family members are discussed.Several new members of EMS family including wind farm EMS，substation EMS and electric vehicle（EV）aggregator EMS are presented，to demonstrate their autonomous characteristics.Interactions among EMS family members are introduced to coordinate the members so as to implement source-grid-demand synergy to form an EMS family network.Several examples of interaction among the EMS family，such as interactions between transmission and distribution，between substations and control center，and between wind farm and EV aggregator，are introduced.