Research On Optimal Scheduling Of Micro-grid Combined Heat And Power

With the introduction of carbon peak and neutrality policies,building a clean and green modern energy system has become an important part of the global energy structure reform.As one of the main ways to save energy and reduce emissions,the comprehensive and efficient use of clean energy helps build an environment-friendly and resource-saving society.Micro-grid combined heat and power(MCHP)has attracted more and more attention at home and abroad because it can meet the energy demand of electric load and heat load with high efficiency,improve the utilization efficiency of renewable energy and realize the cascade utilization of energy.This paper proposes a hierarchical optimal scheduling strategy for independent MCHP to realize the economical and stable operation of the system,and the main work is as follows.Firstly,the scenario analysis method is used to deal with the uncertainty of renewable energy in the micro-grid.The Latin hypercube sampling method is used to sample the cumulative distribution functions of wind speed and light respectively to generate a representative set of renewable energy scenes.The synchronous back generation reduction method is adopted to reduce the number of samples within this scenario set to obtain a typical renewable energy scenario with time-series and original data characteristics.Secondly,in order to achieve global and local coordination of energy management in cogeneration micro-grids,this paper proposes a hierarchical optimal scheduling strategy combining short-term scheduling and ultra-short-term scheduling to improve the operational flexibility of the system.The dynamic feedback correction method is proposed in short-term scheduling to correct the phenomena of frequent start-up and shutdown or the longtime low-power operation of micro gas turbine,and optimize the output of the other devices.While the system operates safely and stably,the utilization efficiency of renewable energy is increased,and the economy of micro-grid operation is improved.The attached penalty cost method is adopted in ultra-short-term scheduling to rationally select equipment to adjust the power deviation between two different time intervals caused by the random fluctuation of renewable energy and loads,so as to enhance the anti-disturbance ability of the micro-grid.Thirdly,in order to increase the accuracy of scheduling instructions,realize the safe and stable operation of the system,and ensure the effective connection between the ultra-short-term scheduling and short-term scheduling,this paper proposes to use the optimization results of short-term scheduling to constrain the ultra-short-term scheduling.On the basis of the short-term scheduling results,the capacity adjustment range of the equipment in the ultra-short-term scheduling is set,so as to achieve a smooth transition and effective connection between the two different time scales of scheduling.Finally,the case simulation results show that the hierarchical optimal scheduling strategy of the independent MCHP proposed in this paper can not only avoid frequent start-stop state and longtime low-power operation of the micro gas turbine,reduce its usage time,decrease the mechanical wear and tear as well as fuel consumption of the equipment,but also make rational and optimal scheduling of each equipment,make full use of renewable energy,and improve the economic and environmental quality of the independent MCHP under the premise of energy balance.