Research On CCHP Microgrid Power Forecasting And Economic Dispatching

At present,changes in global climatic conditions and rising prices of traditional energy sources provide good opportunities for the promotion and development of distributed renewable clean energy,such as solar energy,wind power,and hydropower.The microgrid can integrate these distributed power sources and loads,and maximize the characteristics of each distributed power source.As a powerful supplement to the large power grid system,microgrid can solve the problems of large power fluctuation,high cost and difficult control when distributed generation is connected to the large power grid.Among them,the combined cooling,heating and power(CCHP)microgrid has attracted attention in various fields due to its more complex system load and higher energy utilization rate,which has gradually become one of the second generation energy technology priorities in the future.This article focuses on the power forecast and day-ahead economic optimization operation of CCHP microgrid.The main work is shown as followed:(1)Based on the relevant concepts of the microgrid and the CCHP system,the overall structure and energy supply framework of the CCHP microgrid is built.The mathematical models for a variety of distributed power sources,such as photovoltaics,fans,pumpedstorage power plants,and gas turbines,are established.At the same time,the part of energy supply equipments for CCHP system are described with mathematical formulas,which provide unit equipment model support for the research of CCHP microgrid.(2)Considering the optimized scheduling of CCHP microgrid is based on forecast data,in this paper,photovoltaic power generation and electrical load power are selected as the representative of energy supply side and consumption side to predict.In order to obtain higher prediction accuracy,the improved dragonfly algorithm(IDA)is proposed to optimize the kernel parameters of least squares support vector machine(LSSVM),and the IDALSSVM prediction model is established which carries out the short-term power forecasting for photovoltaic generation and electrical load.Comparing the results with the prediction results of DA-LSSVM model and LSSVM model,it shows that the IDA-LSSVM model has higher prediction accuracy and better generalization ability.(3)Establishing an optimal dispatching model with the goal of minimizing the economic operating costs of the CCHP microgrid.At the same time,considering the complex factors,such as power forecast data,market time-sharing tariff,multi device coupling output constraint and the balance between cold,heat and electric load demand,etc.The improved shuffled frog leaping algorithm(MSFLA)is proposed to calculate the economic operation for grid-connected CCHP microgrid,and the example analysis gives the output of micro-sources under typical daily conditions in different season,which verified the hypothesis presented about micro-net economic operation strategy and the feasibility of the optimization algorithm.