A Multi-time Scale Energy Management Strategy Of Microgrid Based On Demand Side Response

In recent years,the worsening of energy and environmental problems promotes the development of global “low-carbon” and even “decarbonized” energy systems.As the main carrier of grid-connected consumption of renewable energy power generation,the study of multi-source optimal allocation and complementary utilization of micro-grid is crucial to the efficient utilization of renewable energy and to improve the economics of grid operation.However,wind,photovoltaic and other renewable energy power generation and load are random,and multi-energy optimal scheduling on a single generation side and within a single time period will lead to the system's economy is not the best state.Therefore,this paper studies the supply-demand bilateral multi-time scale economic scheduling problem.Firstly,the demand-side resources and response mechanism are studied,focusing on the incentive type and electricity price type demand response.And the flexible load is classified to provide the basis for the demand-side resource calls.In addition,the energy management problem of multi-energy micro-grid system is expounded and the existing optimization schemes are summarized.Secondly,aiming at the “stochastic problem on both sides of supply and demand” in the micro-grid system,a two-time-scale scheduling strategy is proposed based on the correlation between the electroprice-type and the incentive-type response on the time scale to conduct the demand-side resources at a higher level.The day-ahead scheduling adopts the improved time-of-use price to adjust electric load,which taking into account user satisfaction to protect users' interests,and the adjusted load curve is passed to intra-day scheduling stage.According to the short-term predicted power of renewable energy and load,the incentive response mechanism based on the load optimization curve is established in intra-day scheduling stage,and the optimal operation scheme of micro-grid is obtained by minimizing the total operation cost including pollution emission cost.Moreover,in order to further study the multi-energy utilization and its coupling inmicro-grid system,a multi-time-scale scheduling strategy is proposed.In day-ahead scheduling phase,a multi-energy interaction mechanism is established based on the complementary differences in price and demand characteristics of cold,hot and electric energy and load characteristics.The load transfer and the SOC of battery are considered in intra-day scheduling stage,and different battery functions are established in different time periods.Day-ahead scheduling and intra-day scheduling mainly focus on the economy of the system,while the real-time scheduling phase mainly deals with the small fluctuation of renewable energy in short time to ensure the stability of the system.Finally,the proposed scheduling scheme is verified by a simulation example.