发电机励磁系统的非线性大干扰抑制控制器

Nonlinear large disturbance attenuation controller for generator excitation systems

针对具有励磁控制的单机无穷大系统,基于backstepping方法提出了一种非线性大干扰抑制控制方案.重点考虑发电机转子受到外界未知大扰动对系统输出的影响,利用minimax方法可有效降低以往由简单估计干扰上界或不等式放缩带来的保守性,从而确保单机无穷大系统具有良好的鲁棒性和对大干扰的不敏感性.考虑系统受到短路接地故障或者发电机发生机械功率扰动等突发性大干扰的情形,对单机无穷大系统进行仿真实验,结果表明这种控制方案可有效改善电力系统暂态稳定的动态过程.

A nonlinear large disturbance attenuation control scheme is proposed based on the backstepping method for the single-machine infinite-bus excitation system. Focus is given to the impact on the generator rotor caused by the unknown external disturbances on the system output. The minimax method is employed in the disturbance treatment to reduce the conservativeness brought by the estimation of the upper bound of the disturbance and the inequality scaling. This ensures the single-machine infinite-bus system of a high robustness and a low sensitivity to large disturbances. For testing the impact caused by the short-circuit ground fault or the large abrupt disturbances of mechanical power, we perform a simulated experiment on a single-machine infinite-bus system; simulation results show that the control scheme can effectively improve the dynamic process of transient stabilization of the power system.