STATCOM与励磁-汽门开度控制的非线性协调变结构控制方法

Study on nonlinear coordinated variable structure control method of STATCOM and excitation-valve opening control

针对发电机汽门调节系统、励磁系统与STATCOM在协调控制设计中所涉及的多系统暂态稳定性问题,给出了一种基于逆系统理论和自适应变结构控制的非线性协调控制方法.首先,建立了STATCOM、发电机励磁、汽轮机调门的非线性数学模型,利用动态逆系统方法对模型进行线性化解耦;然后,结合变结构控制理论设计出能改善系统动态性能的变结构控制器(VSCC,variable structure coordination controller);最后,通过幂次趋近律结合饱和函数设计新型趋近律来消除由于变结构自身所造成的抖振问题.仿真结果表明,所设计的VSCC相比于发电机励磁-汽轮机调门与STATCOM分开控制的遭受扰动后的响应时间短,能有效地提高系统的暂态性能.

Aiming at the system′s transient stability problem of generator valve regulation system, excitation system and STATCOM in coordinated control design, a nonlinear coordinated control method based on inverse system theory and adaptive variable structure control is presented. The nonlinear mathematical model of STATCOM, generator excitation and turbine valve adjustment is established. The dynamic inverse system method is used to linearize the model. Then, combined with variable structure control theory, a variable structure coordination controller（VSCC） can be designed to improve the dynamic performance of the system. Finally, a new approach law is designed by using power approach law and saturation function to eliminate the chattering problem caused by the variable structure itself. The simulation results show that turbine value and STATCOM controlled the response time after disturbance is shorter. Therefore, the designed VSCC,compared with the generator excitation, can effectively improve the transient performance of the system.