计及频率响应安全性的双馈风电机组轴系阻尼控制策略研究

Research on a shaft damping control strategy for DFIG-based wind turbines considering frequency response safety

由于大规模风电场集中接入电网导致系统频率调节能力下降,风电机组参与系统频率响应的控制策略受到广泛关注。然而,现有研究中缺少频率响应控制对风电机组传动链轴系扭振影响的研究,无法保证频率响应过程中风电机组的安全。为此,提出了一种在频率响应过程中对轴系扭振进行抑制的策略。利用状态观测器对传动链扭转角速度进行估计,通过附加转矩的方式实现频率响应过程中的动态阻尼控制。通过仿真分析和样机实测的方式对本策略与已有的无阻尼控制策略进行了对比,验证了本策略的有效性。

The centralized integration of large-scale wind farms into power grids impairs the frequency regulation capability. The control strategy of wind turbines participating in the system frequency response has attracted wide attention. So far there is few research concerning the effect of frequency response control on the shaft system torsional vibration of the wind turbine drive chain. Thus the safety of wind turbines during the frequency response is yet to be secured. To this end, this paper proposes a strategy to suppress the torsional vibration of the shaft system during the frequency response. A state observer is used to estimate the angular velocity of the drive chain torsion, and the dynamic damping control during the frequency response is achieved using additional torque. The effectiveness of the strategy is verified by comparing it with the existing undamped control strategy through simulation analysis and prototype measurement.