风能转换系统的动态矩阵控制

在实际的变速变桨风力机系统中,模型的强非线性、满负载工况下不稳定的风速及系数参数测量误差的存在,使传统的控制方法难以取得满意的控制效果,因此针对满负载工况下的风能转换系统提出了一种基于多变量动态矩阵控制的控制策略,先构建风能转化系统模型,将时变非线性模型在平衡点处线性化,得到其输入输出偏移量的线性化模型;再利用动态矩阵算法,间接控制发电机转速与功率在额定值处稳定;最后在风轮与电机转动惯量测量误差为40%的情况下进行仿真。结果表明,所得动态矩阵控制器具有较小的波动与较好的鲁棒性,能有效减小系统参数误差的影响,可在安全的工作范围内提供期望的性能,有助于提高电力系统的效率和电能质量。

Dynamic Matrix Predictive Control Algorithm for Wind Energy Conversion System

In actual variable speed variable pitch wind turbine system, the strong nonlinearity of wind turbine model, unsteady wind speed under full load condition and the existence of the measurement error for the system parameter make it difficult for the traditional control methods to obtain satisfactory control effects. Therefore, a control strategy based multivariable dynamic matrix predictive control was proposed for the wind energy conversion system under full load condition. At first, wind energy conversion system was established, and time varying nonlinear model was linearized at the equilibrium point, so the linear model of the offset of input and output was obtained. Then the speed and power of the generator was indirectly controlled to reach the rated values by using dynamic matrix control algorithm. In order to confirm the robustness of the proposed algorithm, simulation was carried out under the circumstance where there is 40% measurement error in the inertia of the wind turbine and generator. The results show that the designed dynamic matrix controller has smaller fluctuation and better robustness. And it can reduce the impact of the measurement error of the system parameters. The expected WECS performance can be provided within a safe working range, which helps to improve the efficiency and power quality of the power system.