风电场参与电网调频的多机协同控制策略

Multi-Machine Cooperative Control Strategy of Wind Farm Participating in Power Grid Frequency Modulation

【目的】考虑风电场中不同风况下风电机组参与一次调频能力的差异,在下垂控制和惯量控制策略的基础上,对机组的调频能力评估方法进行优化。【方法】提出了一种改进的多机组调频参考功率协同控制策略。【结果】引入多机组协同控制方法能够有效改善机组之间调频参考功率的分配,从而有效调节各机组参与系统一次调频的程度。在惯量控制和下垂控制的基础上引入改进的协同控制策略,依据机组在实际风况下运行的状态,评估机组能够有效参与一次调频的参考功率。引入调频能力系数能够实现调频功率参考值在各机组之间按能分配。【结论】协同控制策略能够有效保护风电机组转速,同时能够有效改善电网频率响应。

[Objectives]Considering the difference of primary frequency regulation ability of wind turbines under different wind conditions in wind farms,the evaluation method of frequency regulation capability of wind turbines was optimized on the basis of sag control and inertia control strategy.[Methods]An improved multi-unit frequency modulation reference power cooperative control strategy was proposed.[Results]The introduction of multi-unit cooperative control method can effectively improve the distribution of frequency modulation reference power among units,thus effectively adjust the degree of each unit participating in the primary frequency regulation of the system.An improved cooperative control strategy was introduced on the basis of inertia control and sag control.According to the operation state of the unit under the actual wind condition,the reference power of the unit which can effectively participate in the primary frequency modulation was evaluated.The introduction of frequency modulation capability coefficient can realize the energy distribution of the reference value of frequency modulation power among units.[Conclusions]The cooperative control strategy can effectively protect the speed of wind turbine and improve the frequency response of power grid.