考虑风储协调运行的频率控制策略研究

Research on Frequency Control Strategy Considering Coordinated Operation of Wind Power Storage

随着电网中风电渗透率逐渐升高,研究风电机组的频率控制特性对于提高系统安全稳定运行水平意义重大。与常规同步发电机基于惯性响应、一次及二次调频向系统提供频率支撑不同,双馈风力发电机一般采用电力电子变换器并网,导致其对于系统频率波动几乎没有响应。为此,已有文献提出了不同的风力发电机频率控制策略以提高频率响应。然而,现有控制策略在面对风速较低的运行场景中控制效果极其有限,导致实用性不强。针对上述问题,提出了一种考虑风储协调运行的频率控制策略,以提高双馈风力发电机的调频能力。该控制策略能灵活协调风力发电机和储能设备的有功输出,使得风储联合系统在低、中、高风速不同工况中表现出良好的虚拟惯量控制能力。

With the gradual increase of wind power penetration in power grid,it is of great significance to study the frequency control characteristics of wind turbines for improving the safe and stable operation level of the system.Unlike conventional synchronous generators,which provide frequency support to the system based on inertial response and primary and secondary frequency modulation,doubly fed wind turbines(DFIG)generally use power electronic converters to connect to the grid,resulting in little response to system frequency fluctuations.For this reason,different frequency control strategies of wind turbines have been proposed in literatures to improve the frequency response.However,the existing control strategies have extremely limited control effect in the operation scenarios of low wind speed,resulting in poor practicability.To solve the above problems,a frequency control strategy considering the coordinated operation of wind power storage is proposed to improve the frequency modulation capability of doubly fed wind turbines.The control strategy proposed in this paper can flexibly coordinate the active output of wind turbines and energy storage equipment,so that the combined wind power storage system can exhibit good virtual inertia control capability in different conditions of low,medium and high wind speeds.