基于离散傅里叶变换的微电网混合储能容量优化

Hybrid Energy Storage Capacity Optimization of Microgrid Based on Discrete Fourier Transform

针对并网型微电网中由蓄电池和超级电容组成的混合储能系统进行容量的优化配置。光伏发电和负荷之间产生的净负荷功率由大电网和混合储能装置来共同进行平抑。建立一个俩阶段混合储能容量优化的数学模型,利用离散傅里叶变换对微电网中产生的净负荷功率进行分解,第一阶段在满足联络线功率波动要求的基础上来选取联络线功率和混合储能系统功率的分界点使得联络线利用率最高的;第二阶段以混合储能容量配置的经济成本最低为目标选取蓄电池功率和超级电容功率的分界点;从而得到联络线、蓄电池和超级电容的功率分配。利用遗传算法对混合储能容量的优化模型进行求解,得到最优的混合储能容量的配置。通过算例进行了验证分析。

This paper studies the optimal configuration of capacity of the hybrid energy storage system consisting of batteries and super capacitor in grid connected microgrid.The net load power generated by PV and load is stabilized by large power grid and hybrid energy storage device.The authors established a mathematical model of two-stage optimization for hybrid energy storage capacity and resolved the net load power generated in microgrid by using the discrete Fourier transform(FFT).In the first stage,on the basis of satisfying the requirements of power fluctuation of tie line,the researchers chose the cutoff point of the tie line power and hybrid energy storage power that made the tie line reach the highest utilization ratio.And in the second stage,by taking the lowest economic cost of the hybrid energy storage capacity allocation as the goal,the researchers selected the cut-off point of battery power and super capacitor power,thus obtaining the power allocation of tie line,batteries and super capacitor.Then,the optimization model of hybrid energy storage capacity was solved by using genetic algorithm to obtain the optimal capacity allocation of the hybrid energy storage.In the end,this paper conducted a verified analysis through case study.