考虑机端电压限制的多重非线性变结构励磁控制

针对电力系统暂态过程的非线性特性，设计了一种考虑电压限制的多重非线性变结构励磁控制器，根据控制目标将控制器分2层设计。下层控制器由稳定控制和电压限制控制组成。稳定控制通过计算系统的暂态能量函数，得到稳定流形作为切换面，然后设计相应的变结构非线性励磁控制律，将系统限制在所设计的稳定流形上，以稳定系统；电压限制控制则利用零动态原理，使电压回复到限制区内。上层控制器通过适当的切换律，将下层控制器进行切换，在稳定系统和限制机端电压之间进行协调。在设计时考虑了系统参数不确定性，从而控制律具有一定的鲁棒性。稳定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。实验结果表明所设计的控制器在稳定系统的同时，有效的限制了机端电压。

Multi-layer Nonlinear Variable Structure Excitation Control Considering Voltage Limitation

A novel nonlinear state feedback multi-layer variable structure excitation controller considering voltage limitation is designed to enhance transient stability of power system, which is designed in master-slave control mode. Inside the limitation area, a stabilization control is applied by calculating the transient energy function of the system, and the system designed is limited on the steady manifold by utilizing the variable structure control theory. Outside the limitation area another controller is designed to stabilize terminal voltage via zero dynamic theory. A master controller switches above slave controllers to coordinate them. The parameter uncertainty is considered during the design and the controller is robust to those parameter perturbations. The controller is effective in spite of the nonlinear characteristic of the power system because no linearization method is used. Simulative results show that the designed controller limits the terminal voltage while stabilizing the system during transient stability.