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。     

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.     

利用白噪声激励实现多机系统电力系统稳定器的优化与协调

提出了一种利用白噪声作为激励实现多机电力系统稳定器（PSS）协调优化的方法。这种方法可以在保留系统所有非线性特性的条件下,同时优化多个发电机的PSS参数,减小被白噪声激励系统的目标函数值,提高系统阻尼,从而避免了针对某一频率设计PSS参数时的局限性。实例仿真结果表明,在电力系统运行条件变化的很大范围内,运用这种方法设计的PSS都可以提供较好的阻尼。     

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.     

多机电力系统广泛配置PSS的可行性研究

美国西部电网协调委员会(WSCC)、IEEE都曾建议广泛的配置电力系统稳定器(PSS)。国内各大区域互联系统也有针对性地配置了大量的PSS,提高了系统阻尼,并且有进一步增加配置的趋势。但尚未从理论上证明广泛配置PSS的可行性,对广泛配置PSS的负作用的担心仍然存在。该文探讨多机电力系统中PSS增强系统机电振荡模式阻尼的机理：PSS主要是将非机电模式的阻尼转移给机电振荡模式,从而增强机电振荡模式的阻尼。根据特征根对参数的灵敏度分析结果可知,PSS可以显著提高与本机强相关的机电振荡模式的阻尼,对与本机非强相关的机电振荡模式的阻尼影响不大,广泛配置PSS的正作用远大于负作用。因此多机电力系统中广泛配置PSS是可行的。     

基于进化策略并考虑宽频段补偿的PSS参数优化

将进化策略结合PSS宽频段补偿特性的方法应用到多机电力系统稳定器(PSS)参数优化。考虑到一种运行方式配置的PSS可能在其他运行方式下失效或恶化,以PSS在低频振荡范围内(0.1～2Hz)产生的附加阻尼转矩△Te与△ω尽可能同相位为目标优化超前-滞后环节参数;再以多机PSS在整个系统内产生的最小阻尼比尽量大为目标进行全局优化。New England 10机系统仿真结果表明,这是一种有效的PSS参数优化方法,所得到的参数优化结果对系统运行方式变化有很好的鲁棒性。     

BFO-PSO混合算法的PSS参数优化设计

针对传统PSS参数设计问题,文中基于细菌觅食-微粒群混合优化算法,提出一种协调优化PSS参数的新方法。为了提高电力系统机电振荡模式的阻尼和增加系统的鲁棒性,将阻尼控制器参数设计问题归结为带有不等式约束的目标优化问题,并在目标函数中考虑了多种运行方式,采用细菌觅食-微粒群混合优化算法求解优化问题设计PSS参数。最后通过算例验证了该方法的合理性,是一种对多种运行方式具有良好鲁棒性的阻尼控制器参数优化方法,有效地抑制了低频振荡。     

具有多模型适应性的发电机PSS参数优化方法

现代电力系统中应用配置的电力系统稳定器(PSS)模型不尽相同,而传统PSS参数设计方法仅局限于传统PSS模型。文中提出了具有多模型适应性的发电机PSS参数优化方法,以PSS相位补偿效果为优化目标,采用粒子群算法对该发电机的PSS参数进行优化。该方法对多种PSS模型具有高度适应性,不仅适用于传统的PSS模型,也适用于无超前滞后环节的新型PSS模型。算例表明,采用具有多模型适应性的发电机PSS参数优化方法可有效提升系统阻尼,抑制系统低频振荡。     

多机系统调速侧电力系统稳定器GPSS的设计

低频振荡是一种不利于电力系统安全和稳定运行的现象，而电力系统稳定器(PSS)可以有效抑制低频振荡。由于励磁系统和电力系统运行方式及工况之间的密切关系，致使电力系统中PSS的协调设计和安装地点的选择成了PSS能否用于电力系统的关键。作者设计了一种调速侧电力系统稳定器，其设计原理和传统的PSS一样简单，且具有较好的鲁棒性，同时还具有多机解耦特性，给本机带来阻尼的同时不会给其它机组带来负阻尼，避免了参数协调和安装地点的选择。最后利用算例仿真验证了调速侧电力系统稳定器不仅可以抑制低频振荡，还可以提高电力系统暂态稳定性。     

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.     

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.     

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.     

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     

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。     

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.     

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。