自适应混沌粒子群算法在PSS设计中的应用

该文采用一种改进的粒子群算法PSO———自适应混沌粒子群算法ACPSO,对多机电力系统稳定器参数进行优化设计,以抑制系统低频振荡。该算法通过混沌初始化粒子群,在迭代计算过程中根据粒子的适应值自适应地调整算法惯性系数,从而可以获得更好的全局搜索能力和收敛速度。选取系统机电振荡模式最小阻尼比最大化为目标函数,将PSS参数优化转换为带不等式约束的非线性优化问题。以3机9节点系统为例,特征值和非线性仿真结果表明,运用该方法设计的PSS能够有效地抑制外界扰动引起的低频振荡。     

交直流并联电力系统PSS和直流附加控制器协调优化设计

针对远距离、多区域交直流互联电网低频振荡现象,提出了一种基于改进矩阵束算法的PSS和直流附加控制器协调运行的优化设计。具体包括利用改进矩阵束算法对全网系统辨识,得出系统在没有配置PSS和直流附加控制器时的振荡频率和阻尼比,设定协调优化的目标函数,利用共轭轨迹法优化PSS和直流附加控制器参数;反复利用改进矩阵束算法对系统进行辨识,不断优化协调参数,直到系统逐渐消除低频振荡。仿真结果表明,该协调优化设计可有效抑制电力系统低频振荡,增加系统阻尼,提高系统稳定性。     

基于混沌变异粒子群算法的PSS与SVC阻尼控制器协调优化设计

同步发电机的电力系统稳定器(PSS)与静止无功补偿器(SVC)中附加阻尼控制器相结合可以有效抑制系统低频振荡,从而提高电网的动态稳定性。为使阻尼控制器参数相互匹配,本文提出一种基于混沌变异粒子群优化(CMPSO)算法的PSS与SVC阻尼控制器的参数协调计算方法。该方法以传统粒子群优化(PSO)算法为基础,为避免种群陷入局部最优,算法迭代后期对粒子进行混沌变异操作,从而提高算法的全局搜索能力。综合考虑系统的超调量和响应速率,以阻尼比最大和特征根实部最小为目标函数,将多机电力系统中阻尼控制器参数设计问题转换为带有不等式约束的目标优化问题。在四机两区域系统上的仿真算例表明,CMPSO算法与传统PSO相比具有更好的全局寻优能力。PSS与SVC阻尼控制器的协调优化设计能够在不同的干扰下有效抑制低频振荡,增强电力系统的暂态稳定性,减少故障后的电压波动。     

基于Prony和改进PSO算法的多机PSS参数优化

针对多机电力系统稳定器(PSS)的参数优化问题,提出了采用Prony算法辨识互联电力系统低频振荡的机电模式,利用基于T-S模型模糊自适应的改进微粒群优化(T-SPSO)算法协调PSS参数的控制策略.先采用基于Prony分析的留数法确定PSS的最优安装位置,然后通过对采样数据的Prony分析辨识系统振荡模式的特征值,最后利用所提T-SPSO算法协调优化多机PSS参数.T-SPSO算法根据当前种群最优适应值和惯性权重,自适应更新惯性权重取值,解决了PSO算法的早熟问题.针对IEEE 4机系统的仿真分析表明,基于T-SPSO算法优化后的多机PSS控制器,在2种典型运行方式下都具有更好的控制性能.     

双馈风机附加阻尼控制环节与PSS的参数协调优化

对于含双馈风电场的多机电力系统,在双馈风机内部引入附加阻尼控制环节可以抑制系统低频振荡,但双馈风机附加阻尼控制环节可能会影响电力系统稳定器(PSS)抑制低频振荡的效果。提出了一种双馈风机附加阻尼控制环节与PSS的参数协调优化方法,设计了兼顾机电振荡模式和非机电振荡模式的阻尼特性的优化目标函数,并给出了基于粒子群算法的求解方法。以三机系统作为算例,优化设计了双馈风机附加阻尼控制环节与PSS的参数。时域仿真结果表明,所提出的参数协调优化方法可以更好地提升系统的阻尼,有利于低频振荡的快速平抑。     

多馈入直流输电系统中直流调制的协调优化

文章将带参数约束的非线性最优化方法应用于包含多馈入直流输电系统的交/直流互联电力系统,进行各直流调制之间的协调控制研究.研究方法是最小化包含区域间振荡特性的目标函数,同时优化预先选择的多馈入直流输电系统中各直流调制的参数,最终实现各直流系统调制间的优化调节,在最优和全局协调的方式下增强整个系统对交流系统机电振荡的阻尼.并以中国南方电网2005年的规划网络为实例说明了该方法的有效性和鲁棒性.     

基于混沌优化算法的PSS和直流调制的协调优化

为解决交直流系统中直流调制之间,以及直流调制和PSS之间可能存在的不稳定的相互作用,本文将混沌优化算法应用于包含多馈入直流输电系统的交/直流互联电力系统,进行各直流调制和电力系统稳定器(PSS)之间的协调控制研究。该算法将直流调制和PSS的参数调节问题被转化为基于Lozi映射的混沌优化算法的优化问题,在全局协调的控制方式下增强整个系统对交流系统机电振荡的阻尼。并以中国南方电网的网络为实例说明了该方法的有效性、鲁棒性及其优越性。     

基于飞蛾扑火优化算法的多运行方式电力系统稳定器参数协调优化方法

针对大电网低频振荡现象存在机理分析复杂、振荡模式多样、参与机组众多、传统电力系统稳定器(power system stabilizer,PSS)整定方法适应性较差的问题,提出了一种基于飞蛾扑火优化(moth-flame optimization,MFO)算法的多运行方式PSS参数协调优化方法。该方法首先基于主导振荡模式及动态响应因子提取主要参与机组;然后考虑PSS临界增益及相频特性补偿范围约束,以PSS参数鲁棒性及系统动态稳定性为目标函数;最后采用MATLAB与PSD-BPA联合仿真方法,建立基于MFO算法的多运行方式PSS参数协调优化算法,完成大电网的全局参数寻优。华中电网仿真算例结果表明,应用文中方法优化后的PSS参数可有效提高系统动态稳定性,且对多种运行方式均有较好的适应性,同时算法本身具有较强的收敛性。     

基于HUCPSO算法的电力系统稳定器参数优化方法

电力系统稳定器(PSS)对于抑制电力系统低频振荡简单有效,因而得到了普遍应用。一般采用工程整定方法设计PSS参数,这种方法难以达到优化控制效果。利用辨识参数获得参数初值,采用基于分层多子群的均匀分布混沌粒子群算法(HUCPSO)优化PSS参数,利用2机5节点系统非线性仿真模型对所得参数进行仿真。结果表明,相比于传统方法及其他智能优化算法,采用该方法优化设计的PSS具有更好的性能,所得到的控制参数使系统动态调节性能得到提高。     

基于轨迹灵敏度分析的电力系统稳定器参数优化设计

提出了一种基于时域仿真的电力系统稳定器(PSS)参数优化方法.该方法将PSS的参数设置归结为优化问题,首先通过轨迹灵敏度仿真得到目标函数的梯度信息,再应用共轭梯度技术优化多个PSS参数.由于在目标函数中考虑了电力系统大扰动中的非线性特征,该方法可以抑制小扰动引起的自发性振荡及有效阻尼大扰动引起的系统振荡.在两个IEEE典型系统上进行的特征值分析及时域仿真结果验证了该方法的实用性和有效性.     

Design of a nonlinear power system stabilizer using synergetic control theory

Electromechanical oscillations of small magnitude and low frequency exist in the interconnected power system and often persist for long periods of time. Power system stabilizers (PSSs) are traditionally used to provide damping torque for the synchronous generators to suppress the oscillations by generating supplementary control signals for the generator excitation system. Numerous techniques have previously been proposed to design PSSs but many of them are synthesized based on a linearized model. This paper presents a nonlinear power system stabilizer based on synergetic control theory. Synergetic synthesis of the PSS is based fully on a simplified nonlinear model of the power system. The dynamic characteristics of the proposed PSS are studied in a typical single-machine infinite-bus power system and compared with the cases with a conventional PSS and without a PSS. Simulation results show the proposed PSS is robust for such nonlinear dynamic system and achieves better performance than the conventional PSS in damping oscillations.     

Coordinated stabilizing control for large-scale interconnected power systems,by superconducting magnetic energy storage unit and power system stabilizers

The purpose of large-scale power system interconnection is to achieve extremely economical and reliable power generation and transmission. It has established the present power systems of high quality. On the other hand, in the large power systems with complex configuration, an undamped power swing with low frequency caused by the synchronous power between interconnected systems tends to occur as well as an undamped power swing caused by the synchronous power of specific generators. Several coordinated stabilizing control schemes for the power systems by sets of power system stabilizers (PSSs) have been investigated so far. PSS is very effective for the stabilization of power swing among a few specific generators because the function of PSS is achieved by the voltage control using the generator field winding circuit. However, it seems that PSSs do not have sufficient ability to stabilize the power swings between interconnected systems. In this paper, the superconducting magnetic energy storage (SMES) which is significantly effective for the power swings between interconnected systems is introduced and a coordinated power system stabilizing control by SMES and PSSs is proposed. The advantages of the proposed control scheme are: 1) high efficiency of the controller by the distribution of functions; 2) independency of the control design for PSS and SMES; and 3) robustness of the controller, and so on.     

Load–frequency control of interconnected power system with governor backlash nonlinearities

In this paper, the stability-equation method is applied to the analysis and design of an interconnected power system with governor backlash nonlinearities. The considered system is a nonlinear multivariable feedback control system. The governor nonlinearities tend to produce a sustaining oscillation in area frequency and tie-line power transient responses. Most conventional linear design techniques are usually unable to find the sustaining oscillation in design phase and need simulation verifications to check the validations after designs. However, the proposed method can consider effects of nonlinearities in the design phase. Some nonlinear design techniques need parameters optimization method by Lyapunov theorem or Integral of Square Errors (ISE) criteria. They are effective. However, they need large computation efforts. The proposed method can choice frequency bias parameters and integrator gains of supplementary controllers for avoiding the oscillation or reducing the amplitude of the oscillation to be acceptable. Simulation verifications show that the proposed method can provide a simple and effective way for the considered system.     

Optimization and coordination of damping controls for improvingsystem dynamic performance

This paper presents a global tuning procedure for FACTS device stabilizers (FDS) and power system stabilizers (PSS) in a multi-machine power system using a parameter-constrained nonlinear optimization algorithm implemented in a simulation program. This algorithm deals with such an optimization problem by solving a sequential quadratic programming using the dual algorithm. The main objective of this procedure is to simultaneously optimize pre-selected parameters of the FDSs and PSSs having fixed parameters in coping with the complex nonlinear nature of the power system. By minimizing a nonexplicit target function in which the oscillatory rotor modes of the generators involved and suing characteristics between areas are included, interactions among the FACTS controls under transient conditions in a multimachine power system are improved. A multimachine power system equipped with a TCSC and an SVC as well as three PSSs is applied to demonstrate the efficiency and robustness of the tuning procedure presented. The results obtained from simulations validate the improvement in damping of overall power oscillations in the system in an optimal and globally coordinated manner. The simulations also show that the stabilizers tuned are robust in providing adequate damping for a range of conditions in the system     

Design and allocation of power system stabilizers using the particle swarm optimization technique for an interconnected power system

In this paper, three particle swarm optimization (PSO) based power system stabilizers (PSSs) are developed for three power systems. The system under study here is a power pool consisting of 3 power systems. System I represents the Egyptian power system, system II represents the Jordan and Syrian power systems, and system III for the Libyan power system, which are originally self standing and completely independent systems. As a matter of fact each of them should equipped with its own PSS. For this reason this work is started by designing an optimum power stabilizer for each of them standing alone. After which, the developed PSSs are firstly installed one at a time. Then the three PSSs are installed together in the interconnected power system and their effect on its dynamic performance is studied.As a test for stabilization efficiency, the detailed power system model is subjected to a forced outage of a 600-MW generator, which is the biggest unit in the pool, when it is fully loaded. This outage results in loosing of about 3% of the spinning capacity of system I and about 2% of the spinning capacity of the whole interconnected system. The obtained results show an improvement in the power pool performance accompanied with an improvement in the inter-area oscillation.     

适应复杂电力系统多种运行方式的PSS优化配置

低频振荡的抑制是电力系统规划阶段和运行过程中必须考虑的一个重要问题。抑制低频振荡一般的方法是在励磁调节器上装设电力系统稳定器(PSS)。多机系统中，PSS的配置包括PSS安装位置的选择和参数整定。现有的研究工作主要考虑一种运行方式来进行PSS的优化配置，本文提出了一种同时适应系统的多种运行方式来进行PSS优化配置的方法。通过对西北电网三种典型运行方式的计算结果表明：为了获得更好的抑制低频振荡的效果，PSS的放大倍数不应限定为正值；如按一种运行方式对PSS的参数进行优化则对其它运行方式效果较差，而同时考虑多种运行方式，统一地进行PSS的优化配置则对各种运行方式都能良好地抑制低频振荡。     

多馈入交直流输电系统的模糊控制器协调优化算法

设计了一套阻尼区域间功率振荡的模糊控制器。在多馈入交直流输电系统的直流功率控制系统和发电机励磁系统中同时采用了该模糊控制器,并对影响其性能的关键参数进行了协调优化。为了解决优化结果容易限于局部最优的问题,采用了遗传算法进行全局并行寻优,同时引入序优化理论在概率意义上保证优化解的质量。仿真结果表明:与常规阻尼控制器相比,模糊控制器能更好地提高交直流互联系统的动态稳定性且具有鲁棒性。序优化遗传算法比传统遗传算法具有更稳定的性能,可作为多馈入交直流输电系统的模糊控制器参数协调优化的一种有效方法。     

Global tuning of power-system stabilizers in multi-machine systems

This paper presents a global tuning procedure for conventional PSSs in a multi-machine power system using a non-linear optimization algorithm implemented in a simulation program. The main objective of this procedure is to simultaneously optimize pre-selected parameters of those PSSs having fixed parameters in coping with the complex non-linear natures of the power system. By minimizing a non-explicit target function in which the oscillatory rotor modes of the generators involved and swing characteristics between areas are included, overall power oscillations at transient conditions in the multi-machine system are improved. A four-machine power system is applied to demonstrate the efficiency and robustness of the presented tuning procedure. The results obtained from simulations validate the improvement in damping of overall power oscillations in the system. The simulation also shows that the optimized PSSs are robust in providing adequate damping for a range of conditions on the system.     

交直流互联系统鲁棒自适应直流功率调制

设计了应用于交直流互联电力系统的直流功率调制的非线性鲁棒自适应控制器。该控制器基于驱动各互联区域电网的惯量中心至统一平衡点的设计思想，采用广域测量系统的全局信号，用以阻尼交直流互联系统的区域间功率振荡。采用反步法设计的自适应鲁棒控制规律使控制器对未知参数具有自适应性，对模型误差、扰动和平衡点变化具有较强的鲁棒性。仿真结果表明，与传统的线性直流功率调制控制器相比，该控制器对联络线的功率振荡具有优良的阻尼性能，可显著提高输电极限，而且能很好地适应运行点的变化。