基于储能系统的光伏功率预测误差补偿控制

摘要

Influenced by factors such as weather,the output of photovoltaic modules was non-stationary signal.Its volatility was so violent that the power grid would face a strong impact if the photovoltaic power connects to grid directly.To ensure safe and reliable operation of the photovoltaic grid,the photovoltaic power could be stabilized by controlling energy storage system charging and discharging properly.Wavelet packet analysis was done on the output of the PV power station to determine the target power.Then,combining the frequency response range of chemical cell and super capacitor,the hybrid energy storage system was composed with vanadium redox flow battery and super capacitor charge and discharge using MPC control algorithm.And the simulation was done on Matlab.The result shows that the proposed analysis method and control algorithm have good performance.Finally,according to the method,the battery capacity was determined,and the fluctuation of the battery's energy capacity was described using M-bound to determine the parameters such as the maximum charge and discharge power.%受天气等因素影响,光伏组件的输出功率为非平稳信号,波动性大,直接并网对电网冲击大.为保障光伏并网安全可靠运行,通过控制储能系统合理充放电平抑光伏功率.对光伏电站光伏组件输出功率进行小波包分析确定平抑目标功率,再结合化学电池和超级电容的频率响应范围,采用模型预测控制(MPC)算法控制全钒液流电池和超级电容组成的混合储能系统充放电,并在Matlab上进行仿真.仿真结果表明,此种分析方法及控制策略平抑效果较好.基于此种补偿控制方法确定电池容量,并把“M-界定”量化指标运用到描述电池能量波动,从而确定电池的最大充放电功率等参数.