Research On Optimal Sizing And Coordinated Control Strategy Of Integrated Energy System Of Wind Photovoltaic And Hydrogen

With the gradual rising of severe environmental problems,wind power and photovoltaic power generation have become the principal forms of the development and utilization of renewable energy at present.Because of the wind-light resources' inherent characteristics,randomness,volatility and uncertainty,crucial influence on power grid made by wind power and photovoltaic power generation should never be ignored.The problem of wind power and photovoltaic high proportion penetrating power is very serious.Wind power and photovoltaic power capacity hav e been increasing in recent years.Meanwhile,the ratio of wind curtailment and photovoltaic curtailment have been remaining high.Hydrogen storage,as a recently rising way of power system energy storage,compared with the traditional energy storage ways,has its own advantages,for it is clean and green,has high energy density,large storage capacity,long operating life,and is easy to store and transmit.Therefore,comprehensive development and utilization of coupling hydrogen energy storage will become one of the optimal ways to operate wind power and photovoltaic efficiently.Taking optimal sizing of integrated energy system of wind,photovoltaic and hydrogen into consideration,in-depth analysis is made on wind curtailment/ photovoltaic curtailment/ power fluctuations in this thesis.Model building,coordinated control strategy and online energy control strategy are further studied through simulation and physical experiment.Research innovation of this thesis includes:(1)Optimal sizing of wind curtailment/ photovoltaic curtailment coupling hydrogen generation and fuel cell vehicle system is analyzed quantitatively based on the platform of HOMER.Using the platform of HOMER and taking the scenarios of different fuel cell vehicle load into consideration,the optimal hydrogen production capacity and utilization rate of wind curtailment and photovoltaic curtailment corresponding to minimum cost are analyzed quantitatively according to a case study on a wind farm and photovoltaic station in Jilin.Net pro fit and pollutants emission reduction benefits of the system are further analyzed,based on the platform of Matlab.Considering the improvement of technology and market,economic analysis and optimal sizing of wind curtailment/ photovoltaic curtailment coupling hydrogen generation and fuel cell vehicle system in future are predicted quantitatively.(2)Optimal sizing method of integrated energy system of wind,photovoltaic and hydrogen considering wind and photovoltaic power fluctuations is proposed,based on improved chemical reaction optimization algorithm(ICRO).Improved CROA is put forward,combining CROA's characteristic of strong global optimization and particle swarm's characteristic of fast algorithm convergence speed.Taking maximum profit as objective function,fluctuating power of wind and photovoltaic,capacity of electrolyzer and capacity of fuel cell as constraint conditions,optimal sizing model is established.Economically optimal hydrogen production capacity,fuel cell capacity and the corresponding smooth effect of wind and photovoltaic power are obtained.(3)PSCDA/EMTDC custom model of direct drive permanent magnet synchronous wind turbine,grid-connected photovoltaic array,alkaline hydrogen generation by electrolysis of water and PEMFC grid-connected system are proposed.Validity of the model is verified by experiment.(4)Topology of active direct drive permanent magnet synchronous wind turbine and grid-connected photovoltaic array based on hydrogen energy storage is established.Coordinated control strategy of the system is proposed.Electrolyzer,fuel cell and battery are connected to the DC side of full power converter of active direct drive permanent magnet synchronous wind turbine.Grid-connected power of direct drive permanent magnet synchronous wind turbine can be controlled,using the proposed coordinated control strategy of the system.As an energy buffer,electrolyzer and fuel cell are connected to the DC side of grid-connected photovoltaic array.Super capacitor is applied to relieve the electrolyzer and fuel cell from the problem of slow dynamic response.The green,friendly and active grid-connected photovoltaic array is obtained by the application of the proposed coordinated control strategy.(5)An experimental platform of typical wind,photovoltaic and hydrogen integrated energy system is built and an online energy control strategy of the system is proposed,the effectiveness of which has been verified by digital simulation and physical experiment.The topology of typical integrated energy system of wind,photovoltaic and hydrogen is built,combining it with the idea of integrated energy and the problems of wind curtailment,photovoltaic curtailment and power fluctuations.Online energy control strategy of the system is prop osed.The reasonability of topology of the proposed typical integrated energy system of wind,photovoltaic and hydrogen and the effectiveness of the online energy control strategy are validated,through the integrated energy system digital simulation and physical experiment platform of 3k W direct-drive permanent magnet synchronous wind turbine,5k W grid-connected photovoltaic array,1Nm3/h alkaline hydrogen generation by electrolysis of water and 2.5k W proton exchange membrane fuel cell and 2×5Nm3 hydrogen storage tank.