考虑风机接入的电力系统小信号稳定优化控制

Optimal Supplementary Control for Small Signal Stability of Power System with DFIG Integration

针对风电大规模并网会一定程度削弱系统的小扰动稳定性的问题,建立了含双馈风机的多机系统小干扰稳定分析模型,提出了双馈风机附加阻尼控制策略,并利用遗传算法设计了最优附加阻尼控制器,小信号特征值分析及仿真结果证实了固定风速下该策略所提附加控制的有效性。由于风力机组功率波动会引起上述控制器阻尼效果不稳定,对该DFIG阻尼控制器添加了适应外界风速变化的新算法,仿真结果表明,改进后的附加阻尼控制能在不同风速下稳定地提高系统阻尼特性,具有良好的实用价值。

According to the fact that large amount of integrated wind power can weaken the small signal stability of power system, a supplementary damping control scheme on the maximum power tracking part of DFIG is designed to increase damping of power system. To achieve best performance, parameters of the damping control is tuned by using Genetic Algorithm. Results of eigenvalue analysis and simulation on WSCC three-machine nine-bus system with DFIG integrated demonstrate that the proposed supplementary control scheme can effectively suppress the oscillation of the system. Finally, the above DFIG damping control scheme is improved to be insensitive to the change of wind speed and simulation results show that the new damping control can steadily enhance the system damping characteristics and has high practical value.