微电网概率性最优的储能容量研究

针对可再生能源发电受外界环境影响较大、难以控制，接入微电网后对其安全运行带来很大挑战的问题，指出在微电网中接入储能装置可有效地解决此问题；研究了微电网孤岛运行时储能容量的确定方法，提出了一种概率性最优的储能容量确定方法：计算了微电网调度出力与负荷需求的功率差额，并根据其概率函数密度曲线确定储能系统的最大充放电功率；根据储能系统不同时刻其充、放电量累计值的概率函数密度曲线，求出其最优储能容量，使电网能实现经济效益最优和可再生能源利用率最大。采用该方法确定微电网储能容量，具有求解方法简捷、所需储能容量小的特点。

Study on the Probabilistic Optimal Capacity of Energy Storage in Microgrid

Renewable energy power generation represented by wind power and photovoltaic power is undispatchable and sensitive to the outer environment, which brings great challenge to safe operation of the micro-grid and can be effectively solved by connecting an energy storage system in the microgrid. The method to determine the energy storage capacity is studied when a micro-grid is operated in island state, and a probabilistic method is proposed to determine the optimal energy storage capacity. The power difference between the microgrid’s dispataching capacity and the load demand is firstly calculated, and then the maximum charging and discharging power of the energy storage system is determined through the probability density function curve. The optimal capacity of energy storage system can be obtained according to the probability density function curves of the accumulative charging and discharging power of the storage system at different times, which can improve the economic benefit and renewable energy utilization. The proposed method, when used for determine the microgrid’s energy storage capacity, is straightforward in solution and small in needed storage energy capactiy.