Research On Hybrid Energy Storage System Based On Suppressing Wind Power Fluctuation

The development of industry brings convenience to human life,but also emits a lot of harmful gases to the atmosphere,which leads to the deterioration of the environment and energy shortage.Therefore,many countries are gradually turning to the development of clean and renewable energy.Among them,wind power,as a new technology with abundant resources and clean,has been vigorously promoted in various countries.Wind power generation technology has developed rapidly since its birth,and has gradually matured.However,the uncontrollability and randomness of wind energy make the output of wind power fluctuate greatly.If the wind power is not suppressed,it is easy to produce violent fluctuations of voltage and frequency in the power system,which has a negative impact on the stable operation of the power system.the energy storage equipment controlled by power electronics technology can charge and discharge power rapidly,which can reduce the fluctuation rate of wind power,therefore the method of using energy storage technology to suppress the fluctuation of wind power has attracted more and more attention.With the further development of energy storage technology,hybrid energy storage technology came into being;at present,the use of hybrid energy storage system to suppress wind power has become an important means to reduce power fluctuation in wind farms;in order to achieve wind power suppression,it is necessary to clarify the objectives of wind farm stabilization,power distribution among different energy storage devices,capacity allocation of energy storage equipment and so on.Therefore,the main research contents of this paper are as follows:(1)This paper introduces the basic principle of wind power technology,the structure and characteristics of general wind turbines,three kinds and characteristics of energy storage technology,and two kinds of structure of wind power coupling system.On this basis,the types of wind turbine,energy storage and wind power energy storage coupling system cited in this paper are selected.(2)According to the wind speed data of a wind farm in Xinjiang,according to the general model of wind turbine,the power curve of wind farm is obtained by using MATLAB software,and the fluctuation of wind power is analyzed.Two traditional methods of wind power suppression are briefly introduced: first-order low-pass filtering method and sliding average filtering method.The simulation program is compiled on MATLAB platform,and the wind power is filtered by two methods respectively.The target power of wind farm grid-connected by the two methods is compared from smoothness,fluctuation,fluctuation rate and maximum output/absorption power of energy storage device.(3)After decomposing the wind power and the target output of hybrid energy storage equipment,the target output of hybrid energy storage is analyzed by spectrum analysis: find out the low frequency and high frequency parts,then determine the optimal layer of wavelet decomposition,and decompose the hybrid energy storage power by wavelet decomposition;finally,a power allocation method of energy storage equipment based on the limited coefficient of charging state is proposed.To achieve the redistribution of target power in hybrid energy storage system.