Research On Power Distribution Strategy Of Hybrid Energy Storage System Based On Vanadium Redox Battery

Energy storage technology plays a vital role in promoting energy production and consumption,increasing the proportion of renewable energy connected to the grid,ensuring energy security,and promoting the global green energy revolution.As one of the key support objects in the national strategy "Energy Technology Revolution and Innovation Action Plan(2016-2030)",the vanadium redox battery is being widely used for its long life,large capacity,safety,reliability,clean and pollution-free advantages.In the energy storage system,the hybrid energy storage system combined with the power-type energy storage greatly reduces the operating cost while also meeting the dual requirements of huge energy and rapid response.Therefore,it is of great significance to carry out related researches.In this paper,the following researches are carried out on the power distribution strategy research of the hybrid energy storage system based on the vanadium redox battery.Firstly,the working principle of the vanadium redox battery and super capacitor is introduced.Based on this,the mathematical model and corresponding equivalent circuit model are established,and the charging and discharging methods and capacity expansion structure of the vanadium redox battery are analyzed;on this basis The various topologies of the hybrid energy storage system composed of the two are discussed,and the working principle of the hybrid energy storage system in the power-side photovoltaic scenario is analyzed in detail.Then,establish a power distribution model for the parallel-type vanadium redox battery energy storage system,the differential evolution algorithm and charge-discharge priority strategy are used to optimize the SOC balance and system operating loss of the energy storage system,and compared with the traditional power distribution strategy.On the basis of,carried out the research on the power distribution of the hybrid energy storage system in the photovoltaic electric field,and used the strategy of adaptive wavelet packet decomposition to carry out multi-scale decomposition of the original power signal of the photovoltaic electric field.So as to obtain the grid-connected power signal and the power signal of the hybrid energy storage system;taking into account the characteristics of different types of energy storage systems,the signals of the hybrid energy storage system are divided again to obtain the power value of the super capacitor and the vanadium redox battery energy storage system.And call the power distribution model of the parallel-type vanadium redox battery energy storage system,perform power allocation for each energy storage unit.Then compare and analyze with the first-order low-pass filtering strategy to verify the rationality of the proposed strategy.Finally,the semi-physical control simulation platform structure of the hybrid energy storage system is described,and the hybrid energy storage energy management system based on KING＿VIEW is built to simulate and verify the proposed strategy and expand its engineering application scope.