基于改进射影控制的互联系统附加励磁控制器设计

针对大型互联网络区域间存在低频振荡现象，且一般设计出的附加励磁控制器阶数高、控制效果不理想，在射影控制基础上做出改进，设计出改进射影控制器应用于互联系统的附加励磁控制。首先通过总体最小二乘-旋转不变技术参数估计算法辨识出系统的振荡模态；根据极点配置得到系统的状态反馈矩阵。然后利用射影控制原理，在射影控制器保留p阶主导特征值基础上，又保留了r阶特征值。通过对可调矩阵P0的调节控制系统干扰矩阵 的特征值范围，降低系统原有振荡模式的影响。在PSCAD/EMTDC中的一个四机两区域模型中对无附加控制器、基于观测器-控制器和改进射影控制器控制下的系统进行短路故障和不同时滞下的仿真实验。结果表明，所设计出的改进射影控制器具有更好的阻尼特性和动态效果，且受时滞变化影响较小，具有较好的工程实践性。

Supplementary excitation controller design of interconnected power system based on modified projective control

In allusion to the phenomena of inter-area low frequency oscillation in the big interconnected power system, also, high order of the general supplementary excitation controllers and unsatisfactory control effects exist, a modified projective controller on the basis of projective control is designed and used in the control of supplementary excitation. The oscillation modals are identified by the TLS-ESPRIT algorithm firstly; according to the pole-placement theory, the state feedback matrix of the system is identified; then retaining r order dominant eigenvalue on the basis of the projective control with p order eigenvalue retained; by regulating the adjustable matrix P0 to control the eigenvalue bounds of interference matrix to reduce the influence of original oscillation mode to the system. Simulations of three-phase grounding, one-phase grounding faults and different time delays are done to the system in a model of four machine two domains system without additional controller, with controller based on state observer and modified projective controller in PSCAD/EMTDC. The results validate that the system controlled by the modified projective controller has better damping character and dynamic performance, fewer effects caused by different time delays, and better engineering practice.