使用零动态和变结构控制的发电机非线性综合控制

A Comprehensive Nonlinear Robust Control for Steam-valving and Excitation System Applying Zero Dynamic and Variable Structure Control

针对电力系统暂态过程的非线性特性,利用励磁控制和汽门控制的特点,以功角和电压稳定为目标提出一种发电机汽门和励磁综合控制思想。励磁控制以稳定电压为目标,结合基于零动态和变结构控制的概念和原理进行设计,有效地维持了电压水平。汽门控制以功角稳定为目标,通过计算零动态系统的暂态能量函数,利用Lyapunov稳定理论,得到稳定流形作为切换面,然后设计相应的变结构非线性汽门控制律,将零动态系统限制在所设计的稳定流形上。变结构控制的特性使控制律具有一定的鲁棒性。汽门控制设计中未使用任何线性化方法,因而控制律对系统的非线性特性完全适应。试验结果表明所设计的控制器不仅对小干扰和大干扰暂态过程具有很好的稳定作用,而且在动态过程中能很好地稳定电压,动态过程具有更好的供电品质。

A novel comprehensive nonlinear state feedback controller for steam-valving and excitation system was designed to enhance power system stability. The excitation system controller was designed zero dynamic theory, while to stabilize terminal voltage via steam-valving controller was designed to enhance angle stability via variable structure control. For steam-valving control, a steady manifold was derived by calculating transient energy function of the zero dynamic system and utilizing the Lyapunov theory. The variable structure control law for steam-valving was designed to limit the system state on the steady manifold. The parameter uncertainty was considered during the design and the controller was robust to those parameter perturbations. The controller is effective in spite of nonlinear characteristic of power system because no linearization method is used. Simulation results show that the designed controller performs well for both small signal stability and large disturbance cases.