需求侧管理下智能家庭用电多目标优化控制

针对家庭内附加型负载进行需求侧管理,缓解高峰时刻电网压力,提出一种智能电网环境的家庭用电控制系统。设计了智能控制器,可以获取用户家庭负荷信息并为用户提供分时电价计量,同时便于供电侧直接进行需求侧控制。提出了多目标蜻蜓算法,针对降低负载功率和减少需求响应延时时间两个目标进行求解,其迭代速度快,满足即时响应的需求。500个家庭的实验结果显示,家庭用电控制系统合理,降低了用户用电费用;算法计算速度快,响应时间延时少,有效缓解了高峰时刻的电网负荷。     

考虑节点边际价格的热电联产机组主从博弈竞价策略

本文构建了以热电联产机组(combined heat and power unit,CHP)、电力市场和热力市场为参与者的主从博弈模型,并基于电力市场中节点边际电价(locational marginal electricity price,LMEP)的概念,提出了节点边际热价(locational marginal heat price,LMHP)的概念.在节点边际电价的求解中,采用了支路潮流(branch power flow,BPF)模型,考虑了配电网中的网络损耗从而可以得到更精确的计算结果.在节点边际热价的求解中,考虑了管道热损耗,并基于管道损耗方程分析了节点边际热价的分布规律.在此基础上,采用变步长迭代寻优算法求解热电联产机组、电力市场、热力市场各自最优出力和最优报价策略.最后,通过一个6节点电网–4节点热网的算例对所构建的主从博弈模型及热电联产机组的竞价策略进行了验证.     

Decision making in dynamic stochastic Cournot games

In this paper, the Cournot competition is modeled as a stochastic dynamic game. In the proposed model, a stochastic market price function and stochastic dynamic decision functions of the rivals are considered. Since the optimal decision of a player needs the estimation of the unknown parameters of the market and rivals’ decisions, a combined estimation-optimization algorithm for decision making is proposed. The history of the rivals’ output quantities (supplies) and the market clearing price (MCP) are the only available information to the players. The convergence of the algorithm (for both estimation and decision making processes) is discussed. In addition, the stability conditions of the equilibrium points are analyzed using the converse Lyapunov theorem. Through the case studies, which are performed based on the California Independent System Operator (CA-ISO) historical public data, the theoretical results and the applicability of the proposed method are verified. Moreover, a comparative study among the agents using the proposed method, naïve expectation and adaptive expectation in the market is performed to show the effectiveness and applicability of the proposed method.     

基于多策略协同进化差分算法的社区居民负荷优化调度

针对需求响应下负荷调度的问题,为提供满足居民利益的响应方案,并提高电网运行稳定性,综合考虑电价、激励型需求响应机制与居民用电需求,以用电成本和社区负荷方差最小化为目标,建立了多用户负荷调度高维目标优化模型。结合模型特征提出一种基于多策略的合作协同进化差分进化算法,设计了基于居民用电特征的混合编码与种群初始化策略,以提高解的质量;引入合作协同进化思想将问题变量分解,依据高维目标分组与聚合对种群进行划分,避免陷入局优;各子种群进化时采取双差分模式协同策略,并构建知识迁移个体实现种群间信息交互,最后经贪婪与随机选择结合的种群合并策略保留完整优秀解至外部档案,以提高Pareto最优集的收敛性与分布性。算例仿真表明所提方法可降低社区居民用电成本18%左右、负荷波动方差30%以上;随着居民数量增加,算法的收敛性与多样性与同领域其他算法相比优势更为明显。     

基于区块链的虚拟电厂模型研究

新能源技术和互联网技术推动了电力系统由智能电网向能源互联网进化,未来能源互联网将以分布式能源作为主要的一次能源。虚拟电厂技术能够聚合分布式能源并建立虚拟电力资源交易,逐步成为分布式能源高渗透情况下的核心并网技术。针对以实时电价为驱动的未来能源互联网,结合区块链这一安全、透明、去中心化的分布式计算范式,建立基于区块链的虚拟电厂模型,通过区块链的激励机制将虚拟电厂协调控制手段和分布式能源独立并网行为有机联动,从而实现高效的分布式调度计算。仿真实验表明,所提模型满足能源互联网中分布式能源高渗透率、高自由度、高交易频率、高响应速度的并网需求。     

Design of input vector for day-ahead price forecasting of electricity markets

In new deregulated electricity market, price forecasts have become a fundamental input to an energy company’s decision making and strategy development process. However, the exclusive characteristics of electricity price such as non-stationarity, non-linearity and time-varying volatile structure present a number of challenges for this task. In spite of all performed research on this area in the recent years, there is still essential need for more accurate and robust price forecast methods. Besides, there is a lack of efficient feature selection technique for designing the input vector of electricity price forecast. In this paper, a new two-stage feature selection algorithm composed of modified relief and mutual information (MI) techniques is proposed for this purpose. Moreover, cascaded neural network (CNN) is presented as forecast engine for electricity price prediction. The CNN is composed of cascaded forecasters where each forecaster is a neural network (NN). The proposed feature selection algorithm selects the best set of candidate inputs which is used by the CNN. The proposed method is examined on PJM, Spanish and Ontario electricity markets and compared with some of the most recent price forecast techniques.     

Supply chain intelligence for electricity markets: A smart grid perspective

Smart grid technologies are bringing innovations in electrical power industries, affecting all parts of the electricity supply chain, and leading to changes in market structure, business models and services. In this paper we introduce a model of business intelligence for a smart grid supply chain. The model is developed in order to provide electricity markets with the necessary data flows and information important for the decision making process. The proposed model offers a way to efficiently leverage the new metering architecture and the new capabilities of the grid to reap immediate business value from the huge amounts of disparate data in emerging smart grids. The model was evaluated for the Serbian electricity market in the electric power transmission company Public Enterprise “Elektromre?a Srbije”. The results show that business intelligence solutions can contribute to a more effective management of smart grids, in order to ensure that companies achieve sustainability in the increasingly competitive electricity markets, while still providing the high quality services to end users.     

基于双策略蚁群算法的配电网络重构研究

电网的网络重构本质上属于非线性组合优化问题。随着智能电网的快速发展和电网规模的急剧扩张,网络重构算法的计算复杂度也大幅增加。蚁群算法具有鲁棒性、可并行性和正反馈机制等优点,因而被广泛应用于组合优化问题的求解之中。然而,现有的蚁群算法仍存在计算速度慢,易于陷入局部最优等缺点。为解决上述问题,提出了一种削减-累加双策略的蚁群算法并将其应用于电力系统的网络重构计算中。一方面,定义削减因子,使迭代过程中的蚂蚁数量随算法收敛的稳定程度而不断减少,实现动态自适应的蚂蚁数量选择机制以加快计算速度;另一方面,定义积累因子,增加了信息素的积累阶段,引导算法跳出局部最优,提高找到最优拓扑结构的概率。实验结果表明,在信息素更新次数和初始蚂蚁数量都相同的情况下,与已有工作相比,提出的算法能够将计算速度提升约25%;同时,将最小网损降低约9%。     

一种非线性的分布式网格资源调价算法

针对网格环境下分布式异步动态调价算法存在均衡价格收敛过程缓慢、调价效率较低的缺点,提出了一种基于市场机制的非线性调价算法.该算法结合了当前超额需求和过去超额需求对资源价格变化的影响,较真实地刻画了需求变化后资源价格的波动过程.实验证明,非线性的调价算法明显地提高了价格收敛速度,降低了调价次数.     

混合粒子群算法在微电网经济优化运行的应用

微电网经济优化运行是一个连续的多约束优化问题,其不仅需要对同一时刻的不同微源作出优化,也要协调微源在不同时刻的出力来满足电力供给和负荷需求之间的约束.针对微电网经济优化运行问题,提出一种混合粒子群算法.该算法在随机权重平衡粒子群算法的基础上,引入了免疫机制,使初始粒子的位置较为均匀地分布在坐标平面内.而对于粒子的速度与方向,提出一个非线性权重以提升算法的寻优能力,并加入了次梯度寻优,加快了算法的收敛速度.通过该算法对微电网中可控微源的输出功率做出动态部署,引入微电网系统的市场机制可以有效调配各微源的输出功率,从而提升微电网运行的经济效益.通过对微电网孤岛和并网运行方式进行实例仿真,验证了该方法对微电网经济优化问题具有良好的经济优化作用.     

A Nash equilibrium simulation model for the competitiveness evaluation of the auction based day ahead electricity market

This paper presents a simulation model based on the Nash equilibrium notion for the auction based day ahead electricity generation market. The presented model enhances a previous formalism proposed in the related literature by employing empirical data distributions of the market clearing price as registered by the market authority (e.g. the Independent System Operator). The model is effective when power suppliers with different generation capacities are considered, differently from the starting model that unrealistically assumes equal capacities. The proposed approach aims at evaluating the electricity market competitiveness with regard to the bidder strategies in order to prevent their anticompetitive actions. The framework is applied to a real data set regarding the Italian electricity market to enlighten its effectiveness in different scenarios, varying the number and capacity of participating bidders. The model can be employed as a basis for a decision support tool both for market participants (to define their optimal bidding strategy) and regulators (to avoid collusive strategies).     

基于正则化矩阵分解的用户用电行为分析

针对细粒度、多类别的用户用电行为分析问题,提出了基于地理信息正则化矩阵分解的居民用户用电行为分析算法,探索用户用电的群体特点,为个性化的、更优的电力调度提供决策支持依据。该模型首先基于矩阵分解理论将用户映射到能表征其用电行为特点的潜在特征空间,然后采用k-means聚类算法在潜在特征空间上实现用电用户群的细分聚类。特别地引入了地理信息作为矩阵分解的正则化因子,使得学习到的潜在特征空间不仅满足用户群特征的正交,而且使得地理位置相近的用户在潜在特征空间的映射也相近,与真实物理空间保持一致。将所提方法应用于中新天津生态城智能电网采集到的真实居民用电数据分析挖掘任务中。实验结果表明,与基准的向量空间模型（VSM）和非负矩阵分解（NMF）算法相比,所提方法能够取得更好的用户细分聚类结果,挖掘出一定的用户群体用电模式,有助于辅助智能电网提升经营和服务水平。     

一种基于小波变换和ARIMA的短期电价混合预测模型

为在实时电价情况下预测未来24小时电价, 提出一种基于小波变换和差分自回归移动平均(ARIMA)的短期电价混合预测模型。该模型分别根据是否受到需求量影响使用ARIMA模型对多尺度小波变换分解后的时间序列进行预测。同时提出一种电价突变点发现和处理算法。使用澳大利亚新南威尔士州2012年真实数据验证表明, 相对ARIMA预测, 改进后的混合模型在不考虑需求量影响时预测精度更高; 电价突变点发现和处理算法能够准确处理电价异常点, 提高预测精度。     

Solution to profit based unit commitment problem using particle swarm optimization

In this paper, an algorithm to solve the profit based unit commitment problem (PBUCP) under deregulated environment has been proposed using Particle Swarm Optimization (PSO) intelligent technique to maximize the GENCOs profit. Deregulation in power sector increases the efficiency of electricity production and distribution, offer lower prices, higher quality, a secure and a more reliable product. The proposed algorithm has been developed from the view point of a generation company wishing to maximize its profit in the deregulated power and reserve markets. UC schedule depends on the market price in the deregulated market. In deregulated environment utilities are not required to meet the demand. GENCO can consider a schedule that produce less than the predicted load demand and reserve but creates maximum profit. More number of units are committed when the market price is higher. When more number of generating units are brought online more power is generated and participated in the deregulated market to get maximum profit. This paper presents a new approach of GENCOs profit based unit commitment using PSO technique in a day ahead competitive electricity markets. The profit based unit commitment problem is solved using various PSO techniques such as Chaotic PSO (CPSO), New PSO (NPSO) and Dispersed PSO (DPSO) and the results are compared. Generation, spinning reserve, non-spinning reserve, and system constraints are considered in proposed formulation. The proposed approach has been tested on IEEE-30 bus system with 6 generating units as an individual GENCO. The results obtained are quite encouraging and useful in deregulated market. The algorithm and simulation are carried out using Matlab software.     

Residential virtual power plant with photovoltaic output forecasting and demand response

Decreasing conventional power supply is promoting the development of the distributed renewable energy sources, such as solar power and wind power. Recently rooftop photovoltaic has been widely applied, and accordingly efficient energy management is getting increasingly important for fully use of renewable energy and the peak shaving of the main grid. This paper investigates the residential energy management as a small‐scale virtual power plant (VPP) connected to the main grid includes distributed energy resources, energy storages and residential loads. The self‐organizing map (SOM) and the radical basis function (RBF) networks are adopted to classify the weather types and predict hourly photovoltaic output precisely. In a time‐of‐use electricity market, price‐based demand response is applied to adjust the demand. The residential VPP has two goals: maximum profit by selling surplus power to grid and minimum power purchased from grid. The two goals are integrated as an optimization object by introducing a weight parameter. The algorithm combining receding horizon optimization and linear programming is proposed to solve the optimization problem in residential VPP. Numerical simulation tests can help to find the most suitable value of the weight parameter. Different scenarios are simulated and discussed to demonstrate the performance of the VPP and the proposed algorithm.     

Bollinger bands approach on boosting ABC algorithm and its variants

In this study, a new algorithm that will improve the performance and the solution quality of the ABC (artificial bee colony) algorithm, a swarm intelligence based optimization algorithm is proposed. ABC updates one parameter of the individuals before the fitness evaluation. Bollinger bands is a powerful statistical indicator which is used to predict future stock price trends. By the proposed method an additional update equation for all ABC-based optimization algorithms is developed to speed up the convergence utilizing the statistical power of the Bollinger bands. The proposed algorithm was tested against classical ABC algorithm and recent ABC variants. The results of the proposed method show better performance in comparison with ABC-based algorithm with one parameter update in convergence speed and solution quality.     

电力市场日成交电价预测方法探讨

我国电力体制改革将竞争引入发电供应商之间。在“厂网分开、竞价上网”的电力市场中,发电厂面临如何确定报价,才能使发电厂获得最大利润的问题。而报价的一个重要指标就是预测电力市场日成交电价,所以电价预测对发电厂的报价决策具有重要意义。该文介绍了电力市场日成交电价两种主要预测方法：统计法和神经网络法;并通过分析证明结合两种方法的预测是适合电力市场日成交电价的计算和分析。预测模型对发电商的报价决策系统具有较高的参考价值。     

基于生成模型的Q-learning二分类算法

对于二分类问题,基于判别模型的分类器一般都是寻找一条最优判决边界,容易受到数据波动的影响。针对该问题提出一种基于生成模型的Q-learning二分类算法（BGQ-learning）,将状态和动作分开编码,得到对应各类的判决函数,增加了决策空间的灵活性,同时在求解参数时,采用最小二乘时序差分（TD）算法和半梯度下降法的组合优化方法,加速了参数的收敛速度。设计实验对比了BGQ-learning算法与三种经典分类器以及一种新颖的分类器的分类性能,在UCI数据库七个数据集上的测试结果表明,该算法有着优良的稳定性以及良好的分类精确度。     

智能电网互补能源供用电实时定价算法研究

在智能电网背景下,针对化石能源短缺、峰时供电压力大的现状,提出了由光伏和化石燃料互补供电的方式,并建立了社会福利最大化用户侧微电网实时定价模型。该模型中,电力供应商通过制定实时电价来协调用户对两种类型能源所发电能的使用量,并设计了实时定价算法来求解模型。仿真结果表明,相比仅靠化石能源供电的大电网,互补供电方式能有效降低化石能源峰时供电量和价格,提升社会福利,这为以后智能电网的有效管理提供了参考。     

基于规则网格的层次化布料动态模拟方法

在布料动态模拟仿真过程中,收敛速度和模拟效率是两个核心指标,可以很好的反应布料在动态过程中的模拟效果。针对布料动态模拟中的收敛速度慢、模拟效率低的问题,提出了一种基于规则网格的层次化模拟方法,实现了基于位置的层次化动态模拟。在该方法中,利用层次化思想在原始网格的基础上构建层次化约束网格,在这个过程中,可以采用不同的决策函数对网格进行精简,构造出更加满足目标要求的约束网格,在构造完成后利用提出的权值关联模型对各层次进行再矫正。在模拟过程中,原始网格利用层次化约束网格从最粗层到最精细层进行收敛矫正,有效避免了传统为提高收敛速度而单一的增加约束矫正迭代次数的问题。为了检验模拟性能,布料在周期钟摆风场下进行了实验。实验表明,在基于规则网格的层次化方法模拟下,能很好的解决传统模拟的约束震荡问题,并且效率高,稳定性好。