在一些偏远或海岛地区,考虑到环境保护和燃料成本因素,需要利用可再生能源发电和储能系统形成孤立电网进行独立供电。针对高渗透率大规模风电接入的孤立电网,提出一种风电–储能系统孤立电网控制策略。该控制策略包含上层的广域功率平衡控制和下层的储能设备V/f控制,广域功率平衡控制根据超短期风电功率和负荷预测值以控制代价最小化为目标,确定下一控制周期内风电机组和负荷的最优投切量,并使电网功率波动位于储能设备功率和容量可调范围内;储能设备V/f控制实时检测电网电压和频率偏差生成有功和无功电流指令控制储能系统进行功率补偿。以广东汕头南澳岛为实例进行了具体说明,最后利用Matlab/Simulink软件对所提策略在孤立电网中控制的有效性进行了验证。
Considering the environment protection and fuel cost in remote or island area, renewable energy generation and energy storage systems are utilized to form an isolated grid for power supply. Focus on isolated grids with high penetration and large scale wind generation, a control strategy of isolated grid consisting of wind generation and energy storage is presented in this study. The control strategy contains upper wide area power balance control and lower energy storage V/f control. According to ultra short-term wind power and load forecasts, optimal switching control quantities of wind turbines and loads in next control period are decided by wide area power balance control for minimization of control cost. And then grid power variation can be adjusted within power and capacity range of energy storage system. By real-time detection of voltage and frequency deviation, active and reactive current references are generated for power compensation in V/f control. Guangdong Shantou Nan'ao Island is given as a specific example for illustration. Finally, Matlab/Simulink software is applied to verify the effectiveness of the proposed control strategy in isolated grid.