风电场内多机组输出功率微小波动控制仿真

Simulation of Small Fluctuation Control of Multiple Unit Output Power in Wind Farm

针对风电场出力的随机性与间歇性,其多机组输出功率的波动不具有规律性,可预见性难度较大,不利于风力发电厂供电的稳定性。为此提出风电场多机组输出功率微小波动控制方法。利用风速模型、风轮模型和传动系统模型,研究风电场多机组动力学,明确机组结构和各模块间的关联性。通过多机组功率变化方程描述功率波动,引入推力系数预测机组输出功率。采用模糊控制算法确定比例与量化因子,确立模糊语言集合,建立模糊控制规则,将平衡指标与功率饱和指标作为首层控制器的输入量,计算功率修正系数,实现功率微小波动控制。实验结果表明,在风速和负载实时变化情况下,储能系统和负载侧功率之和与机组输出功率具有一致性,说明研究方法能够保证风电场多机组输出功率的平稳性。

At present,the output of wind farms is random and intermittent,so it is difficult to predict the fluctua-tion of their multi-unit output power.For this reason,a method for controlling small fluctuations of multi-unit output power in wind farms was proposed.Firstly,the wind-speed model,wind turbine model and transmission system model were used to analyze the multi-unit dynamics and thus to clarify the correlation between units and modules.Then,the power fluctuation was described by the multi-unit power variation equation,and the thrust coefficient was introduced to predict the output power of units.On this basis,the fuzzy control algorithm was adopted to determine the proportion and quantification factors and constructed a fuzzy language set,thus establishing a fuzzy control rule.Finally,we took the balance index and power saturation index as the input of the first-layer controller for calculating the power correc-tion coefficient.Thus,the control for the small fluctuation of power was realized.Experimental results show that the sum of the power of the energy storage system and the load side is equal to the output power of the units when the wind speed and load change in real-time,indicating that the proposed method can ensure the stability of the multi-u-nit output power of the wind farm.