Study On Multi-objective Optimal Scheduling Of Photothermal-thermal Power Generation System

Solar energy is a kind of clean energy with considerable reserves for the development of human society,which naturally becomes the representative of primary energy.Photothermal power generation has regulation characteristics comparable to that of conventional units.The influence of the stability and safety of large-scale and high-capacity solar photothermal power stations connected to the grid cannot be ignored.It is necessary to make full use of the controllability and schedulability of the photothermal power station and rationally allocate the heat storage capacity of the photothermal power station.The establishment of photothermal power station model is the basis of scientific control and analysis of the benefits of photothermal power generation.Therefore,it is of long-term significance to study how to make the photothermal power station give full play to its characteristics,cooperate with the conventional thermal power station to jointly generate electricity,and improve the safety,stability and economy of the system.In this paper,firstly,the research status of the combined operation of photothermal and conventional power stations at home and abroad is studied.Carding and comparison analysis,to understand the classification,the structure of the thermal power generation and operation characteristics,the solar-thermal power generation from solar energy to heat energy,and then to electrical energy conversion process and the working principle,analysis of thermal power plant with thermal storage system as the core of each subsystem to light the working characteristic of the thermal power plant,and then study the time shift characteristic of the thermal power plant output and the output can be scheduling.Then,based on the traditional thermal power generation constraints,reasonable regulation of photothermal power generation and heat storage and emission characteristics,and taking the minimum cost of comprehensive power generation as a single objective function,a model of combined photothermal power generation with thermal storage and thermal power generation was constructed.The objective function mainly covers the conventional operation cost of thermal power units,the conventional operation and maintenance cost of photovoltaic power generation,and the environmental protection that can be converted into economic benefits after grid-connected consumption.In matlab,the PSO algorithm is used to optimize the calculation example.Numerical example results show that when into scale given the solar-thermal power generation,made for the optimal operation of daily integrated operation cost,is only depend on the sun light natural output by an average of 108,200 yuan,the cost of saving 9.7%,significantly reduce the burden of the conventional power plants,reduce the operation cost of combined power generation system.Finally,in order to adapt to the conventional fossil energy and clean energy such as solar energy power generation together,combined the development trend of online,give full play to contain the solar-thermal power stations in all kinds of advantages for storing heat,under the premise of considering economy,additional equivalent peak valley load difference to improve and increase the solar-thermal power grid given two objective function,put forward including heat accumulation solar-thermal power stations and thermal power generation of multi-objective optimization scheduling model.PSO algorithm is improved to solve multi-objective optimization problem.The calculation results show that,combined with the actual light amount of four typical dispatch days in spring,summer,autumn and winter,the daily integrated operation cost is still reduced by 43,400 yuan on average,saving 3.99%,and improving the economy of the combined system.The equivalent load variance of CSP power plant decreased by 21.90%on average,and the equivalent load peak-valley difference decreased by 11.15%on average,which reflected the peak load shifting capacity of photothermal power plant and significantly improved the equivalent load curve.And the grid-connected consumption of photothermal power plants increased by 23.17% on average.