在充分分析风电功率幅频特性的基础上,提出基于小波包分解的混合储能技术平抑风电场输出功率波动的方法。采用小波包分解理论对风电场输出功率信号进行多尺度分解,得到反映并网功率信号的低频信号和接入储能系统的高频信号;根据不同类型储能系统的特点,将高频信号再次进行划分,分别选择与其频率范围适应的电池和超级电容器储能设备,建立了基于混合储能系统的风电场输出功率平滑控制模型;与单类型电池储能系统功率平滑效果进行了对比。仿真实例表明:该方法能够有效地抑制风电场输出功率的波动,提高储能电池的使用寿命,具有一定的工程应用价值。
On base of the full analysis for the amplitude frequency characteristics of wind power, a hybrid energy storage system (HESS) based on wavelet packet decomposition in smoothing the fluctuations of wind power is proposed in this paper. The power output signals at a wind farm were decomposed into low frequency signals as grid-connected power and high frequency signals connected into energy storage system by wavelet packet decomposition theory. According to the characteristics of different types of energy storage system, the high frequency signals are divided into different frequency ranges adapting to the batteries and the super capacitors respectively so that the smoothing control model of wind power based on hybrid energy storage system is established. Compared with the smoothing result obtained by the batteries, the simulation examples show that the method provided in this paper can effectively restrain the fluctuations of wind power and improve the use life of the batteries, which has a certain engineering application prospect.