The Portfolio Strategy Research Of Grid-connected Renewable Energy Based On Optimal Control Theory

At present, the use of renewable energy is converted into electrical energy toachieve its end use, thus realizing the large-scale application of renewable energymust solve the problem of grid-connected renewable energy. How to realize the gridcombination of renewable energy and traditional energy generation to developrenewable energy problems must be considered.From the development of renewable energy, this paper focused on the analysis ofthe grid-connected pattern, situation and problems of renewable energy. And on thisbasis this paper set up the general model of renewable energy grid portfolio anddesigned framework model of grid-connected system based on the optimal controltheory, with the grid system operation cost minimum as objective function, the energystorage system’s changes in the smart grid as state constraints. As the case of―thermalpower, wind power, photovoltaic‖grid combination model was used to analyze themodel solving process. Then this paper simulated―thermal power, wind power,photovoltaic‖grid combination model on computer and analyzes the result ofsimulation, using the particle swarm algorithm.The research result showed: the renewable energy grid portfolio strategy modelbased on optimal control theory can effectively apply to the typical―thermal power,wind power, photovoltaic‖grid combination; through the establishment of the optimalcontrol model, iterative calculation and simulation of particle swarm algorithm, it isconcluded that the optimal portfolio value of―thermal power, wind power,photovoltaic‖grid combination is0.4:0.1:0.5; analysis found that the relationshipbetween economies of scale factor and the total cost is decreasing and linear, andgovernment subsidies affects the interconnection system cost but does not affect thechoice of the optimal grid portfolio strategy; the―thermal power, wind power,photovoltaic‖grid combination can effectively reduce the power loss of power gridsystem, beneficial to renewable energy integration into power grid in more effectiveway.