多种无功补偿装置的电压协调控制研究

为了解决分布式电源(Distruted Generation,DG)并网造成功率骤降从而间接使得电压波动的问题,本文根据实际标准选出的多种合适的无功补偿装置进行功率补偿,并通过粒子群算法优化协调各个无功补偿装置使其达到最优状态,得到最小有功网损,使得电压能运行在可控范围之内。文章在IEEE33节点网络的基础上搭建了一个分布式电源并网的无功补偿测试网络作为仿真算例,仿真结果显示所提策略的可行性、有效性。     

基于改进粒子群算法的配电网无功优化

分布式电源的接入配电网有利于其无功优化、改善电压质量、降低网络损耗。以有功网损最小为其无功优化的目标函数,建立相应的数学模型,并对其进行仿真试验。由于基本粒子群算法的系数选择为常系数,存在人为选择系数过多依赖于经验的现象,具有一定的主观与偶然性,会导致粒子过于早熟,陷入局部最优。因此针对常系数粒子群算法的不足,将基于动态权值系数的改进型粒子群算法运用到无功优化中,对含有风、光等分布式电源接入的IEEE33系统模型进行仿真试验分析。试验结果表明,该算法能够有效降低网损,改善电压质量,提高系统的稳定性。     

基于改进遗传算法的分布式电源并网优化配置

随着国家电网对分布式电源并网市场的开放,将分布式电源集成到现有配电系统是今后电力系统的发展趋势。以配电网网损和节点电压偏移最小化为优化目标,考虑支路电流约束、分布式发电单元容量和总接入容量等约束条件,构建大规模分布式电源并网优化配置模型。并提出基于均匀设计的改进遗传算法进行寻优计算,避免了遗传算子的盲目试凑,可以较好地兼顾多目标优化Pareto解集的多样性与快速性,有效提高优化精度。算例对比分析结果表明,通过对分布式电源接入配电网的合理优化配置,可以有效降低系统网损,提高配电网电压的稳定性。     

高渗透率分布式电源并网的无功电压控制研究

为了解决当不同情况下高渗透率分布式电源并入电网时,在传统配电和输电系统中出现一些电压波动较大、网损过高等问题。本文提出一种改进型自适应遗传算法应用在无功电压控制中。首先,采用线性标定的方法对5个最小化问题的目标函数进行标定,加快算法在后期的收敛进程。其次,并采用NSGA-Ⅱ快速非劣支配排序法来求取其中的Pareto前沿解,则多目标问题可化为单目标优化问题。最终可以减少迭代次数,具有很好的全局寻优能力和较快的后期收敛速度,可以使得把最小网损和电压偏差作为目标函数的解多样化且最优。这样高渗透率分布式电源并网条件下的系统电压更稳定,网损减少,从而增强电力系统电能质量可靠性。本文采用把输配电电系统相结合的改进型IEEE30节点模型作为研究对象,探究了输配电系统在含不同渗透率分布式电源下的几个重要指标,其仿真结果证明了本文方法的可行性和有效性。     

含分布式发电的改进BFO算法配电网无功优化

在含分布式电源的电网无功优化研究中,为了更有效地提高配电网性能,提出了一种改进细菌觅食算法(CP-BFO).以电网网损最小、负荷节点电压和发电机的无功出力约束作为综合目标函数,采用细菌觅食算法,在聚焦操作中引入粒子群变异算子,使算法具有良好的全局搜索能力,提高了算法的寻优效率.同时利用混沌原理对改进的细菌觅食算法的参数进行自适应调节,改善了算法的收敛性能.通过节点系统的仿真表明,CP-BFO算法在提高含分布式电源的智能电网电压质量与减少功率损耗的优化过程中具有可行性和有效性.     

山区分布式电源最优接入容量及位置研究

分布式电源接入位置与容量的不同会对电网产生不同影响,如何确定最优的接入位置及容量是保证分布式电源接入系统经济性运行的关键因素。以系统网损最小为目标,考虑到分布式电源接入对系统潮流分布的影响,建立了福建省山区配电网网损目标函数模型,模型中以系统功率及电压为约束条件,提出利用萤火虫优化算法对分布式电源最优接入位置及容量进行寻优。该算法操作简单,具有很好的全局寻优能力。通过算例分析,验证了该算法在求解中的有效性。     

含分布式电源的改进PSO算法配电网无功优化

在电网无功供电性能优化问题的研究中,针对包含分布式电源的配电网无功优化的特点,利用一种改进粒子群算法,对含分布式发电的配电网系统进行了无功优化的计算.考虑了电网损最小、节点电压和发电机无功出力的约束作为优化目标函数,采用粒子群算法,在其速度进化方程中引入了自适应惯性权重和收缩因子以提高,并运用遗传算法中的交叉技术,对PSO算法产生的粒子进行遗传交叉运算来改善全局搜索能力,并在迭代后期将其取消来提高计算速度,仿真结果对比表明,提出的优化算法能够有效地提高电网电压质量和减少功率损耗.     

基于改进量子差分进化的含分布式电源的配电网无功优化

差分进化算法（DE）已被证明为解决无功优化问题的有效方法.随着越来越多的分布式电源并网,对配电网潮流、电压均有一定改变,同时也影响了DE的鲁棒性和性能.本文在研究DE基础上,针对其收敛过早、局部搜索能力较差的缺陷,分析了量子计算思想和人工蜂群算法的优势,提出改进量子差分进化混合算法（IQDE）.通过量子编码思想提高了种群个体的多样性,人工蜂群算法的观察蜂加速进化操作和侦查蜂随机搜索操作分别提高了算法的局部搜索和全局搜索性能.建立以有功网损最小为目标的数学模型,将IQDE算法和DE算法分别用于14节点和30节点标准数据集进行大量仿真实验.实验结果表明,IQDE算法用更少的收敛时间、更小的种群规模便可以获得与DE算法相同甚至更佳的优化效果,并且可以很好的应用于解决难分布式电源的配电网无功优化问题.     

基于Isight的分布式电源优化设计

分布式电源接入配电网是智能电网的关键.分布式电源接入配电网的位置及所注入的容量会对电网的损耗和电压的稳定性产生影响.在综合考虑电压稳定以及电网损耗的基础上建立起分布式电源优化模型,以Isight为优化平台,以MATLAB为数值求解软件,构建并实现分布式电源优化设计计算流程.该方法成功实现降低网损并提高电压稳定性的目标.采用配电网的标准算例对模型和算法进行验证,结果表明该模型具有优异的优化效果,有助于工程的实际应用.     

考虑机组功率因数的分布式风机选址定容研究

随着以风机为主的分布式电源越来越多地并网发电,风电机组选址定容对网络网损的影响也日益凸显.本文考虑机组的最优功率因数,对分布式风机进行选址定容的优化.首先建立了网损的数学模型,得出了网络有功网损和无功网损的公式;随后分析了功率因数对机组选址定容的影响;然后说明了本文所提机组选址定容的具体方法,从确定机组位置、容量到功率...     

Design of reactive power optimization control for electromechanical system based on fuzzy particle swarm optimization algorithm

Due to low precision and premature tendency of traditional particle swarm optimization, the reactive power optimization control of electromechanical system based on fuzzy particle swarm optimization algorithm was designed. The premise is to meet the constraints of operation conditions. The active network loss was reduced and the static reactive power optimization mathematical model of electromechanical system was constructed by changing the voltage and reactive power distribution of system. Meanwhile, the voltage did not exceed the limit, and the discrete control variables were limited by the maximum allowable action times, so that the dynamic reactive power optimization mathematical model of electromechanical system was built by minimizing the sum of network loss in twenty-four hours of a day. The particle swarm algorithm was optimized by adaptive adjustment strategy, and then the particle position of particle swarm optimization algorithm was updated. Moreover, the static and dynamic reactive power optimization mathematical model of electromechanical system was solved. Finally, the reactive power optimization control of the electromechanical system is realized. Experimental results show that the proposed method has high convergence performance, so it is able to realize the precise control of reactive power optimization for electromechanical system and eliminate the voltage exceeding specified limits of electromechanical system. In this way, the node voltage can always be within the specified range.     

基于随机自适应粒子群算法的电力系统无功优化

无功优化是保证电力系统安全经济运行的有效手段,是提高电力系统电压质量的重要措施之一。本文首先介绍无功优化的一般数学模型,然后重点分析粒子群优化算法的组成结构与工作原理,进而提出一种改进的粒子群优化算法。该算法采用随机自适应策略,能够对当前所产生的局部最优值进行变异,再重回粒子群算法中搜寻全局最优值,从而可以有效改善传统粒子群算法求解电力系统无功优化问题时存在的收敛精度不高、容易陷入局部最优等不足,一定程度上提高了粒子群算法的寻优能力。最后,通过在IEEE 30节点上进行仿真实验比较,结果表明该算法是可行和有效的,达到了提高供电质量、降低线损的目的。     

基于混合算法的含分布式电源的配电网优化

考虑到分布式电源的选址与定容对配电网有着重要影响意义,针对分布式电源的接入对配电网系统能量损耗和各节点电压影响的问题,首先建立了以有功功率损耗和系统节点电压的目标函数优化模型,提出了充分整合引力搜索算法(GSA)的勘探能力和粒子群(PSO)的开采能力的混合算法(PSOG-SA),同时确定权重系数,最后采用IEEE-33标准节点配电网模型进行了仿真实验,通过和其他两种算法的比较,验证了配电网系统在该算法下的有效性和可靠性.算例分析表明,合理的DG接入能够一定程度上降低系统有功功率损耗,改善节点电压.     

电力系统无功优化的柯西粒子群算法

针对传统粒子群算法易陷入局部最优解、收敛速度慢的缺点,提出了柯西粒子群算法,并首次将其应用于电力系统无功优化问题.柯西粒子群算法是基于柯西分布的期望和方差均不存在的原理,对每一代粒子的全局极值进行柯西变异,以此来增加种群的多样性,扩大全局最优粒子的搜索区域,以尽快获得适应度更优的个体,从而可以避免算法陷入局部最优解,同...     

基于改进遗传算法的风/光互补发电系统电压无功控制

在风/光互补发电系统中,风、光资源的随机性强,导致系统电压的稳定性差,电压控制显得尤为重要.电压控制通常通过区域无功功率的优化来实现.无功功率优化是一个带有约束的多极值非线性组合优化问题,用传统的方法很难进行处理.因此提出一种改进的遗传算法用以风光/互补发电系统的无功功率优化,该算法在一般遗传算法的基础上,对编码方式、遗传算子以及终止判据等方面作了改进.通过算例分析表明,改进的算法能够显著的提高收敛速度和计算精度,有效的实现电压的无功控制.     

Krill herd algorithm for optimal location of distributed generator in radial distribution system

Distributed generator (DG) is recognized as a viable solution for controlling line losses, bus voltage, voltage stability, etc. and represents a new era for distribution systems. This paper focuses on developing an approach for placement of DG in order to minimize the active power loss and energy loss of distribution lines while maintaining bus voltage and voltage stability index within specified limits of a given power system. The optimization is carried out on the basis of optimal location and optimal size of DG. This paper developed a new, efficient and novel krill herd algorithm (KHA) method for solving the optimal DG allocation problem of distribution networks. To test the feasibility and effectiveness, the proposed KH algorithm is tested on standard 33-bus, 69-bus and 118-bus radial distribution networks. The simulation results indicate that installing DG in the optimal location can significantly reduce the power loss of distributed power system. Moreover, the numerical results, compared with other stochastic search algorithms like genetic algorithm (GA), particle swarm optimization (PSO), combined GA and PSO (GA/PSO) and loss sensitivity factor simulated annealing (LSFSA), show that KHA could find better quality solutions.     

Optimal reactive power dispatch by particle swarm optimization with an aging leader and challengers

This study presents a particle swarm optimization (PSO) with an aging leader and challengers (ALC-PSO) for the solution of optimal reactive power dispatch (ORPD) problem. The ORPD problem is formulated as a nonlinear constrained single-objective optimization problem where the real power loss and the total voltage deviations are to be minimized separately. In order to evaluate the performance of the proposed algorithm, it has been implemented on IEEE 30-, 57- and 118-bus test power systems and the optimal results obtained are compared with those of the other evolutionary optimization techniques surfaced in the recent state-of-the-art literature. The results presented in this paper demonstrate the potential of the proposed approach and show its effectiveness and robustness for solving the ORPD problem of power system.     

Genetic evolving ant direction particle swarm optimization algorithm for optimal power flow with non-smooth cost functions and statistical analysis

This paper presents an evolving ant direction particle swarm optimization algorithm for solving the optimal power flow problem with non-smooth and non-convex generator cost characteristics. In this method, ant colony search is used to find a suitable velocity updating operator for particle swarm optimization and the ant colony parameters are evolved using genetic algorithm approach. To update the velocities for particle swarm optimization, five velocity updating operators are used in this method. The power flow problem is solved by the Newton–Raphson method. The feasibility of the proposed method was tested on IEEE 30-bus, IEEE 39-bus and IEEE-57 bus systems with three different objective functions. Several cases were investigated to test and validate the effectiveness of the proposed method in finding the optimal solution. Simulation results prove that the proposed method provides better results compared to classical particle swarm optimization and other methods recently reported in the literature. An innovative statistical analysis based on central tendency measures and dispersion measures was carried out on the bus voltage profiles and voltage stability indices.     

基于多目标飞蛾算法的电力系统无功优化研究

鉴于电力需求的日益增长与传统无功优化方法的桎梏,如何更加合理有效地解决电力系统的无功优化问题逐渐成为了研究的热点。提出一种多目标飞蛾扑火算法来解决电力系统多目标无功优化的问题,算法引入固定大小的外部储存机制、自适应的网格和筛选机制来有效存储和提升无功优化问题的帕累托最优解集,算法采用CEC2009标准多目标测试函数来进行仿真实验,并与两种经典算法进行性能的对比分析。此外,在电力系统IEEE 30节点上将该算法与MOPSO,NGSGA-II算法的求解结果进行比较分析的结果表明,多目标飞蛾算法具有良好的性能,并在解决电力系统多目标无功优化问题上具有良好的潜力。     

Dynamic optimal reactive power dispatch based on parallel particle swarm optimization algorithm

In this paper, Message Passing Interface (MPI) based parallel computation and particle swarm optimization (PSO) algorithm are combined to form the parallel particle swarm optimization (PPSO) method for solving the dynamic optimal reactive power dispatch (DORPD) problem in power systems. In the proposed algorithm, the DORPD problem is divided into smaller ones, which can be carried out concurrently by multi-processors. This method is evaluated on a group of IEEE power systems test cases with time-varying loads in which the control of the generator terminal voltages, tap position of transformers and reactive power sources are involved to minimize the transmission power loss and the costs of adjusting the control devices. The simulation results demonstrate the accuracy of the PPSO algorithm and its capability of greatly reducing the runtimes of the DORPD programs.