风火打捆外送系统次同步振荡的改进自抗扰直流附加阻尼控制

针对送端电网大规模风电接入可能加剧火电机组次同步振荡的问题，提出一种基于改进遗传算法的自抗扰附加阻尼控制方法。利用基于总体最小二乘法-旋转不变技术的信号参数估计(TLS-ESPRIT)算法对系统进行次同步振荡特性辨识，根据主模比指标选择合适的控制反馈信号，得到系统在次同步频段内各振荡模式对应的低阶传递函数；结合时间乘绝对误差积分准则(ITAE)指标与极大极小值原理确定被控系统控制目标，并利用改进遗传算法寻优确定多通道自抗扰控制器参数。在PSCAD上搭建含大规模风电的测试系统模型，仿真结果表明基于改进自抗扰控制的附加次同步阻尼控制器在送端电网多种运行方式和不同故障情况下都能有效抑制汽轮发电机组的次同步振荡，鲁棒性较强，同时低阶自抗扰控制器也具有令人满意的控制效果。

DC additional damping control of subsynchronous oscillation based on improved active disturbance rejection control for wind-thermal-bundled power system

Aiming at the problem that the interconnection of large scale wind power to the sending end of power grid may intensify the subsynchronous oscillation of thermal power units, an active disturbance rejection damping control method based on improved genetic algorithm is proposed. The TLS-ESPRIT(Total Least Squares-Estimation of Signal Parameters via Rotational Invariance Techniques) algorithm is used to identify the subsynchronous oscillation characteristics of the power system, the suitable feedback signal is selected according to the dominant mode ratio index, and the low order transfer functions corresponding to each oscillation mode in subsynchronous frequency band are obtained, and the control objectives of controlled system are determined by combining the ITAE(Integral Time Absolute Error) index and the minimax principle, and the parameters of multi channel active disturbance rejection controller are searched by the improved genetic algorithm. A test system model with large scale wind power is constructed on PSCAD, and the simulative results show that the supplementary subsynchronous damping controller based on the improved active disturbance rejection control can effectively suppress the subsynchronous oscillation of steam turbine units under multiple operation modes and fault conditions of sending power grid, and it has strong robustness and satisfactory control effect.