基于Hamilton能量函数法的机电扰动控制器设计

发布时间：2018-06-14 07:11

本文选题：Hamilton能量函数 + 常值实现　；参考：《西南交通大学》2017年硕士论文

【摘要】：现代电力系统是一个典型的高维数、强非线性复杂动态系统,其正常运行时不断遭受各种各样的扰动。因此,电力系统的安全稳定问题一直受到人们的广泛关注。电力系统故障时,汽门控制能够减少因机械功率与电磁功率不平衡而引起的转速波动和功角摆动,有利于系统重新建立同步。励磁控制能调节发电机机端电压和无功功率,是电力系统控制领域最常用最经济的控制手段之一。将汽门控制和励磁控制相结合,能提高系统故障后的收敛速度,有利于系统更快地建立稳定。早期电力系统的控制器主要是基于非线性系统在运行点附近进行线性化下设计的,但电力系统的强非线性使得采用局部线性化法设计的控制器不能适应电力系统受到大扰动后对暂态性能的要求。近年来,非线性控制已经广泛用于电力系统中,并取得了丰富的成果。Hamilton能量函数是非线性理论的重要组成部分。本文针对带汽门开度控制的发电机模型,基于Hamilton能量理论,提出了两种有效的控制方法。首先,本文首次将常值实现法,即结构矩阵为常值的一种广义Hamilton实现,应用于带汽门开度控制的单机无穷大系统,将系统表示成广义Hamilton系统,并设计了励磁和汽门协调控制的机电扰动控制器。针对单机无穷大系统,首次从特征根的角度确定基于Hamilton能量函数所设计的机电扰动控制器的系数。在控制器设计中未用到线性化方法,所得扰动控制器充分利用了系统的非线性特性。本文基于常值实现法设计的励磁和汽门协调控制的机电扰动控制器与单独的励磁控制器以及传统的PID控制器相比,提高了系统发生故障时的收敛速度,当系统平衡点漂移,该扰动控制器在提高收敛速度的同时能够减少系统频率漂移。最后,基于单机无穷大系统的仿真结果验证了本文所提出的机电扰动控制器的有效性和正确性。其次,首次将Hamilton能量理论和L2干扰抑制的思想应用于含有转移导纳且考虑汽门开度控制的多机系统模型,完成了多机系统的伪广义Hamilton实现,设计了励磁和汽门协调控制的机电扰动控制器,具有明确的物理意义。基于Hamilton能量函数法,保留了系统的非线性特性,避开了直接构造Lyapunov函数的困难,具有良好的控制效果。本文采用WECC的3机9节点系统的作为算例来验证本文所设计机电扰动控制器的正确性和有效性。仿真结果表明,励磁和汽门协调控制的机电扰动控制器与单独的励磁控制器相比,提高了系统扰动发生后的收敛速度,减少系统频率的漂移,提高了系统的暂态稳定性。
[Abstract]:Modern power system is a typical high-dimensional, strongly nonlinear complex dynamic system, which is subjected to various disturbances in its normal operation. Therefore, the safety and stability of power system has been paid more and more attention. In the fault of power system, the valve control can reduce the fluctuation of rotational speed and the swing of power angle caused by the imbalance between mechanical power and electromagnetic power, which is helpful to re-establish the synchronization of the system. Excitation control can regulate generator terminal voltage and reactive power, which is one of the most common and economical control methods in power system control field. The combination of valve control and excitation control can improve the convergence rate of the system after failure and help the system to establish stability more quickly. The controller of the early power system was designed mainly based on the linearization of the nonlinear system near the operating point. However, because of the strong nonlinearity of power system, the controller designed by local linearization method can not meet the requirements of transient performance of power system after large disturbance. In recent years, nonlinear control has been widely used in power systems, and has achieved rich results. Hamilton energy function is an important part of nonlinear theory. In this paper, based on Hamilton energy theory, two effective control methods are proposed for generator model with valve opening control. First of all, in this paper, the constant realization method, a generalized Hamiltonian realization with structure matrix as constant value, is first applied to a single-machine infinite system with valve-opening control, and the system is expressed as a generalized Hamilton system. An electromechanical disturbance controller for excitation and valve coordinated control is designed. For a single machine infinite bus system, the coefficients of the electromechanical disturbance controller designed based on Hamilton energy function are determined for the first time from the point of view of eigenvalue. The linearization method is not used in the controller design, and the disturbance controller makes full use of the nonlinear characteristics of the system. Compared with the single excitation controller and the traditional pid controller, the electromechanical disturbance controller of excitation and valve coordination control based on the constant realization method is designed in this paper, which improves the convergence rate of the system when the system fails, and when the equilibrium point of the system drifts, The disturbance controller can reduce the frequency drift of the system while improving the convergence rate. Finally, the simulation results based on single machine infinite bus system verify the validity and correctness of the electromechanical disturbance controller proposed in this paper. Secondly, the Hamilton energy theory and the idea of L2 interference suppression are applied to the multi-machine system model with transfer admittance and considering the valve opening control for the first time, and the pseudo-generalized Hamilton realization of the multi-machine system is completed. The electromechanical disturbance controller for excitation and valve coordinated control is designed, which is of definite physical significance. Based on Hamilton energy function method, the nonlinear characteristics of the system are preserved, and the difficulty of constructing Lyapunov function is avoided. In this paper, the correctness and validity of the electromechanical disturbance controller designed in this paper are verified by using the 3-machine 9-bus system of WECC as an example. The simulation results show that compared with the single excitation controller, the electromechanical disturbance controller controlled by excitation and valve harmoniously improves the convergence rate of the system after disturbance occurs, reduces the drift of the system frequency, and improves the transient stability of the system.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM712

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