Research On Micro Grid Energy Management Strategy Based On Hybrid Energy Storage

Micro grid as a kind of renewable energy and other distributed power supply integrated technology can improve the reliability of distributed generation system,realize the integration of distributed power supply and the load,and can grid or off grid operation with flexible operating characteristics,which has become an important part in the construction of smart grid.Micro grid energy management system is the core of the micro grid coordinated control and energy management strategy can guarantee the reasonable effective use of renewable energy and micro grid economic operation optimization.At present,the research and development of micro grid energy management strategy is not yet mature,and there are many problems to be studied urgently.The main contents of this paper include:Firstly,the running characteristics of distributed power supply in micro grid are researched and analyzed,including the wind turbine,photovoltaic cell,micro gas turbine,battery and super capacitor,and the mathematical models of distributed generation are established.The classification of demand side load is summarized,and then aiming at the heating load of residential building in the demand side,a heat transfer characteristic model is established based on the heat balance equation.The floor heating system composed of different storage and heat production capacity of low temperature radiant floor and different thermal storage and thermal insulation properties of the housing wall is simulated and its thermal storage potential is analyzed.Secondly,residential buildings heated by the floor heating system are integrated into the residential micro-grid as a virtual energy storage system,and three different types of co-generation residential micro-grids are constructed.On the basis of this,the energy management strategy of hybrid energy storage residential micro grid including conventional electric energy storage and virtual energy storage is researched and a micro grid energy management model with economy and user comfort as objective is established.By regulating the room temperature in the range of temperature comfort,the virtual energy storage system is involved in the optimization and regulation to realize the charging and discharging management of the virtual energy storage,thus reducing the operation cost of the micro grid.Finally,taking the winter heating scenario as an example,for the three different types of residential micro grids,the differences of charge and discharge characteristics between virtual energy storage and actual energy storage devices are analyzed.The scheduling results under different conditions such as low temperature radiant floor with different thermal storage and storage capacity,house wall with different thermal storage and thermal insulation properties are analyzed.The results show that the proposed energy management strategy can fully tap the storage potential of residential buildings on the demand side,thus effectively reducing the operating costs of micro grids and improving the comprehensive energy efficiency of micro grids under the premise of ensuring user comfort.