多机电力系统中的浑沌现象

根据高维动态系统的Melnikov理论，对多机电力系统中的浑沌现象进行了较深入的 研究，从理论上分析了多机电力系统中浑沌现象的性质以及出现浑沌现象的条件;同时还给 出了对一个简单多机电力系统例题进行浑沌现象分析所得的结果。     

稳定器设计的就地相位补偿法在多机电力系统中的应用

为了演示和验证稳定器设计的就地相位补偿法在多机电力系统中的应用,介绍在多机电力系统中,就地补偿设计稳定器的2个应用实例。第1个实例是在多机电力系统中就地补偿设计电力系统稳定器(power system stabilizer,PSS),阻尼电力系统局部模振荡。第2个实例是就地补偿设计附加在静态同步补偿器(static synchronous compensator,STATCOM)上的稳定器,抑制多机电力系统中的区域模振荡,并给出在一个16机电力系统中的应用计算和仿真结果。     

稳定控制研究中的多机电力系统数学模型

【摘要】 〖ＨＴＫ〗 进行电力系统稳定控制研究时，必须首先建立研究对象的数学模型。由于选取 不同的电机数学模型和不同的 轴系，多机电力系统的数学模型有多种不同形 式。本文较详细地介绍了几种常用的多机电力系统数学模型，并着重阐明其间 的差别和特点。最后对如何确定系统的稳定平衡平衡点或控制目标进行了讨论 ，并论述了多机电力系统观测解耦状态空间模型，据此可以通过局部测量构成 局部控制器并达到全局稳定的目的。     

多机电力系统非线性振荡的研究

多机电力系统低频振荡中出现的Hopf分岐，或称之为非线性振荡，是以往低频振荡研究领域中所未接触的新问题，分析的主要工作是求解系统出现这种非线性振荡时的曲率系数，该文利用复变量构建的一维中心子空间和数值法求出了曲率系数，解决了以往算法只以用于简单系统而不适于多机电力系统的问题，成功地完成了多机电力系统非线性振荡的分析。获得了一些新见解，新观点，为研究发生在多机电力系统中的这种非线性奇异现象提供了个有效的工具。     

电力系统的人—机—环境系统分析

人－机－环境系统的质量是电力系统现代化的重要标志之一。文中结合电力系统的实际，对人－机－环境系统进行了探讨，并着重对人－机、机－环、人－环、机－机、环－环、人－人等关系及其综合效应进行分析，提出全面开展电力系统的人－机－环境系统应用性研究势在必行。     

电力系统稳定器实现于调速系统之研究 第二部分：多机系统中特性分析

本文利用MIMO频域理论，通过引入附加阻尼比矩阵，论证了调速侧电力系统稳定器GPSS具有 多机解耦特性，给出了多机电力系统中GPSS的设计方法和一个三机系统设计示例。理论分析 和仿真结果均表明，基于相位补偿原理的单机系统GPSS设计方法可以推广于多机系统，从而 ，避免了多机PSS参数协调的难题，有效地抑制了系统中的增幅低频振荡和弱阻尼振荡。     

神经网络电力系统稳定器之研究

基于动态神经网络构造了一种电力系统稳定器(NNPSS)通过单、多机数字仿真研究了神经网络控制器应用于电力系统实时控制所面临的两个问题：未知扰动下控制输出的合理性；(2)单机—无穷大母线系统下训练的控制器在多机系统中的控效果。文章详细介绍了NNPSS的设计思想，训练样本选取单、多机仿真结果分析。     

电力系统在一种极限运行状态下的稳定性分析

针对电力系统出现一对共轭虚根的静态稳定极限运动状态，在分歧理论的基础上，提出了稳定性分析的数值微分算法，解决了这类稳定性分析中必须涉及的相关高阶偏导数的计算问题，以及计算中如何选取增量的问题，成功地完成了这种极限运动状态的稳定性分析，实际电力系统算例表明，文中所给出的理论，方法是正确和有效的，特别适合于复杂的多机电力系统，为分析多机电力系统极限运动状态下的稳定性提供了一个有效的途径和工具。     

应用非线性控制理论抑制电力系统多模振荡的研究

利用非线性变换和线性系统中的ITAE最佳调节律，设计了一个新型的非线性最优电力系 统稳定器（NIPSS）；基于多机电力系统模型，导得了用本地测量量实现每台机组的解 耦控制律。在一个具有多模振荡的多机电力系统上进行了数字仿真，结果表明：所设计的N IPSS能有效地抑制电力系统多模振荡，有满意的动态响应和很好的鲁棒性；并且，NI PSS能和其它类型的PSS协调运行，共同提高多机系统的阻尼特性。     

多机电力系统中PSS和OEC配置及参数整定的统一解法

本文提出了一种利用线性规划逼近非线性规划的原理和“相关因子”的概念，以解决多机龟力系统在多运行方式下，电力系统稳定器和最优励磁控制器参数及配置的统一协调方法。对西北电网的初步研究表明，本文速度快、效果好。     

多机系统在参数扰动下的周期解

研究了多机系统受到功率或线路阻抗扰动时的周期解，建立了相应的数字模型，利用空间周期解理论导出了多机系统产生周期解的一些条件。文中所讨论的扰动可以是强振性的，这为研究机互联系统所产生的低频振荡现象提供了理论分析基础。     

Optimal locations and tuning of robust power system stabilizer using genetic algorithms

Optimal locations and design of robust multimachine power system stabilizers (PSSs) using genetic algorithms (GA) is presented in this paper. The PSS parameters and locations are computed to assure maximum damping performance under different operating conditions. The efficacy of this technique in damping local and inter-area modes of oscillations in multimachine power systems is confirmed through nonlinear simulation results and eigenvalues analysis.     

电力系统稳定器实现于调速系统之研究 第二部分：多机系统中特性分析

本文利用MIMO频域理论,通过引入附加阻尼比矩阵,论证了调速侧电力系统稳定器GPSS具有多机解耦特性,给出了多机电力系统中GPSS的设计方法和一个三机系统设计示例。理论分析和仿真结果均表明,基于相位补偿原理的单机系统GPSS设计方法可以推广于多机系统,从而,避免了多机PSS参数协调的难题,有效地抑制了系统中的增幅低频振荡和弱阻尼振荡。     

多机系统直流输电引起的次同步振荡的研究

本文导出了由多机系统直流输电引起的次同步振荡的线性化数学模型,并对一多机系统直流输电引起的次同步振荡问题进行了特征值研究,讨论了直流输电控制方式、控制参数及运行工况对次同步振荡的影响。     

多机电力系统再同步最优变目标控制

本文在最优目标控制（ＯＡＣ）的基础上，根据电力系统再同步的特点，提出再同步最优变目标控制（ＯＶＡＣ）策略。该控制策略首先驱动系统到达按最大稳定域选择的人工中间稳定平衡点，然后才驱动系统到达所希望的稳定平衡点。所得到的再同步励磁和快关汽门综合控制规律是根据多机电力系统观测解耦状态空间模型导出的，仅需要获得局部信息，而且能形成闭环反馈控制，因此容易实现。通过数字仿真表明，最优变目标控制能使电力系统快速可靠地再同步。     

Stabilization of power systems by governor-turbine control

In this paper, the possibility of applying a Power System Stabilizer (PSS) via the governor-turbine system of a generating unit is studied for both single-machine and multimachine power systems. The results of analysis and simulation show that the conventional exciter-based PSS can be used in conjunction with the modern high-speed governor to suppress low-frequency oscillations in power systems. This arrangement of stabilizer possesses better robustness to the changes of power system operating conditions. Furthermore, in the environment of a multimachine power system, the control of PSS on the governor of every generator can be locally synthesized to stabilize the whole system, PSS design becomes much easier and simpler.     

Equivalent turbogenerator model for design of multivariable controllers in multimachine systems

The design of multivariable controllers for turbogenerators is usually based on single-machine infinite-bus representations, which are not valid for multimachine power systems. Alternatively, an overall control strategy may be sought for all the generators in the system, but this arrangement is not feasible in practice and involves major mathematical difficulties. The paper describes a method for designing physically-realizable multivariable controllers for individual turbogenerators in multimachine systems, without the assumption of an infinite bus. This employs an equivalent model for each generator, which includes the effects of interconnections with other units in the power system. The method has been used to design optimal state-space controllers for a three-machine system, and results obtained by nonlinear computer simulation show that good performance is achieved.     

Stability assessment of multimachine power systems using multivariable frequency response methods

Two feedback representations of linearized models of power systems are presented. One features torque loops and the other exciter loops. The torque loops representation is used to study damping and synchronizing torque coefficients. In the power system community, stability of linear models is associated with positive damping torques. Design of controllers is based on maximizing damping torques. A previous result that used the Nyquist criterion showed that in a single-machine infinite-busbar system a positive damping torque is sufficient but not necessary for the system to be stable. This result is stated briefly and generalized to multimachine power systems using the generalized Nyquist stability theorem. A multimachine system is used to demonstrate the results. The excitation loops are also investigated and the role of system zeros explained.     

A new-fangled adaptive mutation breeder genetic optimization of global multi-machine power system stabilizer

This paper presents the design and implementation of Power System Stabilizers in a multimachine power system based on innovative evolutionary algorithm overtly as Breeder Genetic Algorithm with Adaptive Mutation. For the analysis purpose a Conventional Power System Stabilizer was also designed and implemented in the same system. Simulation results on multimachine systems subjected to small perturbation and three phase fault radiates the effectiveness and robustness of the proposed Power System Stabilizers over a wide range of operating conditions and system configurations. The results have shown that Adaptive Mutation Breeder Genetic Algorithms are well suited for optimal tuning of Power System Stabilizers and they work better than conventional Genetic Algorithm, since they have been designed to work on continuous domain. This proposed Power System Stabilizer is demonstrated through a weakly connected three multi-machine test systems.     

Optimal multiobjective design of robust power system stabilizers using genetic algorithms

Optimal multiobjective design of robust multimachine power system stabilizers (PSSs) using genetic algorithms is presented in this paper. A conventional speed-based lead-lag PSS is used in this work. The multimachine power system operating at various loading conditions and system configurations is treated as a finite set of plants. The stabilizers are tuned to simultaneously shift the lightly damped and undamped electromechanical modes of all plants to a prescribed zone in the s-plane. A multiobjective problem is formulated to optimize a composite set of objective functions comprising the damping factor, and the damping ratio of the lightly damped electromechanical modes. The problem of robustly selecting the parameters of the power system stabilizers is converted to an optimization problem which is solved by a genetic algorithm with the eigenvalue-based multiobjective function. The effectiveness of the suggested technique in damping local and interarea modes of oscillations in multimachine power systems, over a wide range of loading conditions and system configurations, is confirmed through eigenvalue analysis and nonlinear simulation results.