多机电力系统非线性自适应励磁控制器的设计

Design of Nonlinear Adaptive Excitation Controller for Multi-machine Power System

为了增强多机电力系统的动态稳定性,提升电力系统平抑负荷扰动的能力,本文提出了一种基于自适应反步技术的非线性自适应励磁控制方案。由于发电机的机械功率和阻尼系数受系统运行状态的影响,因此可以直接视为未知数,利用自适应定律估算出来这些未知量。根据李雅普诺夫(Lyapunov)函数的形式推导出自适应规律,保证发电机的转子角速度、机端电压、输出功率等不同物理量均收敛。然后在4机11母线的电力系统输电线路上仿真三相短路故障,测量转子转速偏差,对所提出的控制方案进行评估,并与现有的反步控制器和常规电力系统稳定器(CPSS)进行了比较。根据仿真结果,本文所提出的方法比现有的两种控制器的控制效果更有效。

This paper presents a nonlinear adaptive excitation control scheme to enhance the dynamic stability of multimachine power systems.The proposed controller is designed based on the adaptive backstepping technique where the mechanical power input to the generators and the damping coefficient of each generator are considered as unknown.These unknown quantities are estimated through the adaption laws.The adaption laws are obtained from the formulation of Lyapunov functions which guarantee the convergence of different physical quantities of generators such as the relative speed,terminal voltage,and electrical power output.The proposed scheme is evaluated by applying a three-phase short-circuit fault at one of the key transmission lines in an 4-generator and 11-bus test power system and compared with an existing backstepping controller and conventional power system stabilizer(CPSS).Simulation results show that the proposed scheme is much more effective than existing controllers.