考虑储能荷电状态的风储联合调频控制策略

Wind Turbine and Storage Joint Frequency Modulation Control Strategy Considering Energy Storage State of Charge

储能配合风电参与调频可以改善一次调频效果,但储能荷电状态(state of charge,SOC)接近上下限值时会出现储能功率不足,此时储能SOC保护与调频效果很难兼顾。综合考虑风速和负荷随机变化的复杂工况下的调频需求,提出一种考虑储能SOC的风储联合调频控制策略,在SOC处于标准值附近时储能以最大下垂系数充放电,在储能SOC偏高或偏低时采用考虑SOC自适应的充放电控制策略保护SOC,同时风电机组通过变下垂控制弥补储能出力不足,以此改善调频效果。最后,通过MATLAB/Simulink仿真及风−储联合调频实验平台进行验证。实验结果表明,相比一次调频和SOC自适应调频方法,本文所提策略的频率偏移度及SOC偏移度均有明显降低,所提控制策略兼顾了调频效果及SOC保护。

Energy storage with wind power participating in frequency regulation can improve the effect of a frequency regulation,whereas the state of charge(SOC)close to the upper and lower limits of the energy storage power will be insufficient.At this time,storage SOC protection and frequency regulation effect is difficult to take into account.In this paper,considering the demand for frequency regulation under the complex working conditions of random changes in wind speed and load,a wind-storage joint frequency regulation control strategy considering the energy storage SOC is proposed.The energy storage is charged and discharged with the maximum sag coefficient when the SOC is near the standard value,and the SOC adaptive charging and discharging control strategy considering the SOC is used to protect the SOC when the energy storage SOC is high or low in this strategy.Meanwhile,the wind turbine compensates for the storage output by variable sag control so as to improve the effect of frequency regulation.Finally,the strategy of this paper is verified by MATLAB/Simulink simulation and wind-storage joint frequency control experimental platform.The experimental results show that the frequency offset and SOC offset of this paper’s strategy are significantly reduced compared with the primary frequency modulation and SOC adaptive control strategy,and the proposed control strategy takes into account the frequency regulation effect and SOC protection.