基于指数平滑与CEEMDAN的混合储能控制策略研究

Hybrid energy storage control strategy based on exponential smoothing and CEEMDAN

随着风电并入电网渗透率的提高,其出力波动性会危及电力系统的安全稳定运行,混合储能装置的使用能很好地平抑风电并网的波动,改善电网的运行能力。为符合国家并网的标准,文章提出了混合储能控制策略。首先,运用指数平滑法滤除风电出力的高频分量得到并网功率;其次,采用自适应噪声的完整集合经验模态分解,将风电波动功率按频率高低依次划分为不同的固有模态分量,计算相邻固有模态分量的互信息来分离高频和低频分量,并分别由电池和超级电容承担低频、高频分量;为了消除荷电状态越限的问题,采用自适应调整分界点实现储能内部协调优化运行。算例结果表明,文章所提出的控制策略具有一定的适用性,能确保储能装置运行在安全荷电状态,延长其运行寿命。

With the continuous increase of the penetration rate of wind power into the power grid,the volatility of its output will endanger the safe and stable operation of the power system.The use of hybrid energy storage devices can well stabilize the fluctuation of wind power grid connection and improve the operational capacity of the grid.Firstly,To meet the national grid-connected standards,the high-frequency components are filtered out by the exponential smoothing method for wind power output and the grid-connected power is obtained.Secondly,the power fluctuation of wind power is divided into different intrinsic modal components from high frequency to low frequency by using CEEMDAN and calculating the mutual information of adjacent natural modal components to separate the high frequency and low frequency components.The battery and the super capacitor are designed to absorb the low frequency and the high frequency;To eliminate the overrun problem of the state of charge,it is necessary to adapt to the adjustment demarcation point to achieve internal coordination and optimization operation of energy storage.The results of the example show that the proposed control strategy has certain applicability,which can ensure the state of charge in the safe range and prolong the operating life of energy storage.