基于总体平均经验模态分解的混合储能系统协调优化控制

摘要

由于光伏发电具有较强的随机性和波动性,利用储能系统能够有效平抑光伏功率的波动.该文提出了基于总体平均经验模态分解(ensemble empirical mode decomposition,EEMD)的混合储能协调优化控制方法.首先,根据光伏并网波动率限制要求调整EEMD的滤波阶次k1,将光伏功率分解为高频分量和低频分量,然后,将分解后的低频分量作为光伏电站的并网功率实现光伏功率的平滑控制.为了提高混合储能系统使用寿命,根据电池和超级电容器的荷电状态(state of charge,SOC)对滤波阶数k2进行调整,实现电池和超级电容器之间的能量分配.根据电池和超级电容器的充放电优先级规则,实现超级电容器和储能电池之间的功率最优控制.通过仿真实例验证了本文方法的有效性和正确性.%Due to the strong randomness and volatility of the photovoltaic power generation,the energy storage system can be used to effectively stabilize the fluctuation of the photovoltaic output power. This paper proposes a coordinated optimization control method of hybrid energy storage system (HESS) bases on ensemble empirical mode decomposition (EEMD). The photovoltaic output power is decomposed into the high frequency component and low frequency component by adjusting the filter order k1of the EEMD according to the fluctuation rate limit of the photovoltaic output power,and the low frequency component is regarded as the connected grid power to achieve a smoothing control of the photovoltaic output power. In order to improve the service life of hybrid energy storage system,according to the SOC (state of charge) of batteries and super capacitors,the filter order k2of the EEMD is adjusted to realize the energy distribution between batteries and super capacitors. According to the priority rule of charge and discharge of batteries and super capacitors, the optimal control between super capacitors and batteries is realized. The effectiveness and correctness of the proposed method are verified by a simulation example.