Electric Power Network Oligopoly as a Dynamic Stackelberg Game

Over the last two decades, the electricity industry has shifted from regulation of monopolistic and centralized utilities towards deregulation and promoted competition. With increased competition in electric power markets, system operators are recognizing their pivotal role in ensuring the efficient operation of the electric grid and the maximization of social welfare. In this article, we propose a hypothetical new market of dynamic spatial network equilibrium among consumers, system operators and electricity generators as solution of a dynamic Stackelberg game. In that game, generators form an oligopoly and act as Cournot-Nash competitors who non-cooperatively maximize their own profits. The market monitor attempts to increase social welfare by intelligently employing equilibrium congestion pricing anticipating the actions of generators. The market monitor influences the generators by charging network access fees that influence power flows towards a perfectly competitive scenario. Our approach anticipates uncompetitive behavior and minimizes the impacts upon society. The resulting game is modeled as a Mathematical Program with Equilibrium Constraints (MPEC). We present an illustrative example as well as a stylized 15-node network of the Western European electric grid.     

Market power and welfare effects in DC power flow electricity models with thermal line losses

A nodal electric power network with Cournot–Nash interaction among power generators is formulated as a mixed complementarity problem. The model incorporates a direct current (DC) power flow approximation with thermal line losses to model real-time flows. We include constant wheeling rate and variable congestion charges for transmission of electricity. Market power and welfare effects are measured in an aggregated Indiana electric grid model. We find that imposing DC power flow constraints in a model results in significant changes in social welfare estimates. Line losses are also an important factor affecting market power and welfare of market participants in the case study.     

A Large-Scale Spatial Optimization Model of the European Electricity Market

In this paper, we present a large-scale spatial model of the European electricity market including both generation and the physical transmission network (DC Load Flow approach). The model was developed to analyze various questions on market design, congestion management, and investment decisions, with a focus on Germany and Continental Europe. It is a bottom-up model combining electrical engineering and economics: its objective function is welfare maximization, subject to line flow, energy balance, and generation constraints. The model provides simulations on an hourly basis, taking into account variable demand, wind input, unit commitment, start-up costs, pump storage, and other details. Various forms of spatial price discrimination can be implemented, such as locational marginal pricing (“nodal pricing”), or zonal pricing. With over 2,000 nodes and over 3,000 lines, this is one of the largest models developed to date, and allows a highly differentiated spatial analysis. We report modeling results regarding efficient congestion management for Germany and Europe, optimal network expansion under the aspect of increased wind energy production, and the impact of network constraints on location decisions of generation investments.     

基于神经网络评价的农村电网投资分配决策研究

农村电网是配电网中较为薄弱的一个环节,加之乡村振兴等政策的提出,迫切需要加大对农村电网的投资,提升电压合格率、供电可靠性等问题,但是传统的主观分配方法已经不能满足电网收益率的要求。本文从农村电网设备投资模型出发,通过讨论传统的电网投资分配模型与分配方法,提出了基于BP神经网络评价的新型农村电网投资分配方式,进一步的验证方法的可靠性,并以安顺市县级农村电网为例,讨论所提方法的可行性,对供电企业的农村电网投资提供一定参考意义。     

Generation strategies for gaming transmission constraints: will the deregulated electric power market be an oligopoly?

Constrained transmission lines are known to be able to economically isolate submarkets from the competition of players located elsewhere on the network. This paper examines the type of oligopolistic competition that is likely to take place in these submarkets. It shows, using simple models, how static or intertemporal Nash equilibria can rise in a framework of price or supply function competitions, found to be more realistic than Cournot models in the particular case of short-term competition in the electric power market. This paper shows also how transmission constraints can play a direct role in the outcome of the oligopolistic competition and encourage strategic behavior by the generators. Transmission lines that would not be constrained if the players did not know of their thermal limits may be strategically driven to operate at these limits in order to maximize the profits of the players who have market power, leaving the others to cope with the consequences of such behavior.     

基于云网格集成调度的防拥堵车辆路径规划算法

在道路交通路网中,车辆拥堵问题是流量与路网结构之间相互作用的一个复杂动态过程,通过车辆路径规划,实现对路网网格集成调度,从而提高路网通行吞吐量。传统方法采用并行微观交通动态负载平衡预测算法实现车辆拥堵调度和车辆路径规划,不能准确判断路面上的车辆密度,路径规划效益不好。提出一种基于云网格集成调度的防拥堵车辆路径规划算法,即构建基于Small-World模型的云网格路网模型,采用RFID标签信息进行路况信息采集,实现交通网络拥堵评估信息特征的提取,采用固有模态函数加权平均求得各车道的车辆拥塞状态函数,对所有车道内车辆密度取统计平均可获得簇内的车辆密度。设计交通路网拥堵检测算法来对当前个体道路信息进行一维邻域搜索,从而实现车辆路径规划控制目标函数最佳寻优。通过动态博弈的方式求得车辆防拥堵路径的近似最优轨迹,实现路径规划算法的改进。仿真结果表明,该算法能准确规划车辆路径,实现最优路径控制,从而提高严重拥堵路段的车流速度和路网吞吐性能,性能优越。     

受成本约束的电力信息?物理相依系统鲁棒性优化设计

针对复杂网络视角,考虑到电力网络存在扩建等现实问题,研究受成本约束下如何增设站点从而优化负荷分布、改善系统的鲁棒性。基于华中地区某省电力网的拓扑结构数据,构建了电力网与信息网部分一一对应的相依网络模型,并采用非线性负载?容量模型作为系统的级联失效模型。考虑实际电力网中超前规划新增厂站的现实情况,提出4种可能的增设电力节点及其信息设备对应的节点配置优化策略,并对华中某省电力网及IEEE 118 总线的电力信息?物理系统在4种节点配置策略下的电力负荷优化及系统鲁棒性进行仿真及分析。仿真结果表明:以配置的物理节点连接网络中大电力负荷及小电力负荷节点为基准时,仅需配置较少的节点就能达到既定的优化度。本结论对于电力系统在建设与规划过程中将有限资源进行较优分配具有一定的指导意义。     

基于电力大数据的用户用电感知研究

在基于电力大数据对用户提供多元化服务的研究中,发现电网在不同时刻停电,不同用户的停电感受不一样以及在调度计划制定时,由于不同线路所带用户不同需进行差异化服务。为此,提出基于电力大数据的用户用电感知研究。首先通过电网内部系统及外部系统进行数据采集,然后基于大数据从多维度进行数据处理和分析,建立了用电需求模型和用户用电感知模型并进行了深入应用;通过该模型可以实现有限投资供电可靠性提升最快,最大限度满足用户需求;可最大限度实现不同行业、类别的用户用电互补,提高设备利用率;可实现用电感知最低时段停电,停电涉及用户更精准。该模型的引用实现了电网规划、用户接入、调度运行的智能决策,使电网规划投资更精准,固定投资提升可靠性最快,提高设备利用效率和用户满意度。     

Competition and Cooperation in a Bidding Model of Electrical Energy Trade

A cooperative game-theoretic framework is introduced to study the behavior of cooperating and competing electrical-energy providers in the wholesale market considering price-preference rational consumers. We study the physical and economic aspects of the power transmission system operation focussing on the incentives for group formation. We analyze the interactions of generators in an idealized environment described by a DC load flow model where the network is lossless and is operated by an independent network operator who ensures network stability and fulfillment of consumption needs while taking into account the preferences of consumers over generators. We show that cooperation of generators may be necessary to divert consumers from their previous providers. In the second part of the paper we assume an iterative process in which the generators publish their price offers simultaneously, based on which the consumers preferences are determined. We study the dynamics of the prices and profits as the system evolves in time while each coalition is trying to maximize its expected profit in each step. The model deals with network congestion and n ? 1 line-contingency reliability as not every generator-consumer matching is allowed to ensure the safe operation of the transmission system. The profit of the generators is determined as the difference between their income and their production cost, which is a quadratic concave function of the production amount. Any non-monopolistic proper subset of the generators may cooperate and harmonize their offered prices to increase their resulting profit. Since we allow the redistribution of profits among cooperating generators, a transferable-utility game-theoretic framework is used. Furthermore, as cooperation affects the outsiders as well, the resulting game is defined in partition function form. The model is able to demonstrate some interesting benefits of cooperation as well as the effect of market regulations and asymmetric information on the resulting profits and total social cost.     

电网工程无功补偿配置原则及问题分析

针对电网无功配置不足或过剩将会造成电网电压波动、电网调度运行管控困难、设备利用率低、电网投资浪费、不利于电力系统安全稳定运行等问题。本文从电网工程可行性研究报告的评审角度出发,提出了电网无功补偿装置配置原则,明确了接入电网的基本要求和功率因数的补偿要求,同时在电网工程可行性研究阶段变电站无功补偿配置的设计思路和方法基础上,结合电力系统中无功负荷（损耗）、无功电源等计算过程,对电网工程无功配置设计中普遍存在无功负荷统计值偏大、忽略无功电源提供的无功功率和忽视电容器组投切电压波动及谐波校验等问题进行分析和总结,提出变电站无功补偿选型设计和评审过程中关注的要点,以达到在确保电网安全可靠运行的基础上,经济合理配置无功补偿设备,提高电力系统经济运行水平,节省电网工程建设投资的目的。     

Network Topology and Locational Market Power

This paper studies the effect of network topology and production constraints on the locational market power of generators. A market power spectrum is considered where one end has infinitely large production capacity but the usual network constraints while the other end has infinitely large network capacity but the usual production constraints. First, we analyze the locational market power function mathematically. Then, we use a real world example of the Portland, Oregon electrical market and determine its position on the market power spectrum. We find the Portland market to be primarily production constrained rather than network constrained. We also identify the local and global threshold generation capacities for each generator beyond which it cannot influence the individual and total locational market power, respectively. This study facilitates the understanding of the economic and physical determinants of locational market power. It can help regulators make informed decisions when it comes to the choice of enhancing the physical infrastructure, or adding more generation capacity to the market.     

A General Equilibrium Framework for Integrated Assessment of Transport and Economic Impacts

The use of separate transport and economic models in urban planning provides a limited view of economic impacts, restricts the testing of network design options and lengthens the planning process. Furthermore, the standard methodology for economic appraisal assumes partial economic equilibrium and cannot determine the distribution of impacts from the transport sector to households. Computable general equilibrium (CGE) models can capture general equilibrium effects and measure welfare at the household level, but mostly lack integration with transport models and do not represent all trip generators. This paper develops an integrated traffic assignment and spatial CGE model in nonlinear complementarity form, casted as a framework for economic appraisal of urban transport projects. The CGE submodel generates commuting, shopping and leisure trips as inputs into the transport submodel, which then assigns trips to the network according to user equilibrium. The resulting travel times then feed back into household prices and freight margins. Households and firms fully account for travel times in decisions on where to shop, how much labour to supply and where to source production inputs. Calibration and applications of the model are demonstrated for 14 regions and 2 industries across Sydney using GAMS/PATH on the NEOS server. The welfare of various network improvements is measured using equivalent variations. The model can be calibrated to external strategic transport models, and be extended to simulate additional trip generators and land-use.     

基于局部离群点检测算法的电力通信网络拥塞安全控制方法

针对电网运行数据堵塞程度较高,传输安全性较差的问题,提出了基于局部离群点检测算法的电力通信网络拥塞安全控制方法。通过电力通信网络的通道模型与路由监测协定,凭借波特间隔均衡法优化节点布局,结合自适应偏差补充调整反馈,均衡通道。针对储存空间、带宽容量、CPU处置功能等主要拥塞因素,分析数据密度估计值,并在带宽函数中加入邻域平均距离得到局部密度,推导出数据的局部离群点,通过调节离群点大小断定和控制电力通信网络。实验证明,所提方法能够精准检测出电力通信网络是否拥塞,及时调节通信数据,降低堵塞程度,保证信息可以安全传输。     

A case study on a hybrid wind speed forecasting method using BP neural network

Wind energy, which is intermittent by nature, can have a significant impact on power grid security, power system operation, and market economics, especially in areas with a high level of wind power penetration. Wind speed forecasting has been a vital part of wind farm planning and the operational planning of power grids with the aim of reducing greenhouse gas emissions. Improving the accuracy of wind speed forecasting algorithms has significant technological and economic impacts on these activities, and significant research efforts have addressed this aim recently. However, there is no single best forecasting algorithm that can be applied to any wind farm due to the fact that wind speed patterns can be very different between wind farms and are usually influenced by many factors that are location-specific and difficult to control. In this paper, we propose a new hybrid wind speed forecasting method based on a back-propagation (BP) neural network and the idea of eliminating seasonal effects from actual wind speed datasets using seasonal exponential adjustment. This method can forecast the daily average wind speed one year ahead with lower mean absolute errors compared to figures obtained without adjustment, as demonstrated by a case study conducted using a wind speed dataset collected from the Minqin area in China from 2001 to 2006.     

Competitive energy consumption under transmission constraints in a multi-supplier power grid system

Power grid architectures need to be revised in order to manage the increasing number of producers and, more generally, the decentralisation of energy production and distribution. In this work, we describe a multi-supplier multi-consumer congestion model of a power grid, where the costs of consumers depend on the congestion in nodes and arcs of the power supply network. The consumer goal is both to meet their energy demand and to minimise the costs. We show that the methods of non-atomic routing can be applied in this model in order to describe current distribution in the network. We formulate a consumer cost minimisation game for this setting, and discuss the challenges arising in equilibrium search for this game.     

基于差分进化算法的分布式电源DG规划设计

分布式电源(DG)是一种可以与环境兼容,利用清洁能源发电,可以满足用户对电量的特殊需求的发电装置。因此,将分布式电源接入电网,不仅可以保证电网的运行安全,提高供电可靠性,还可以将多余的电力反馈给电网。分布式发电接入配电网后,不一定能降低配电系统的网损,提高电网的稳定性,还有可能会因为并网的规划方案设计的不够好反而对电网造成不利影响,因此,分布式电源接入配电网的规划尤为重要。在分布式发电的并网规划中,最重要的是选择分布式发电的接入位置和容量。因此,本文选择具有结构简单、执行方便、优化效率高、参数设置简单、鲁棒性好等优点的差分算法,通过建立系统,并用Matlab进行了仿真,选择其最佳位置,计算出最优容量,并得到最优目标函数,来达到最佳的规划设计。     

基于GIS的电网规划系统设计与实现

电网规划是电网建设的关键环节,电网系统的规划是一项非常复杂的工程.传统的电网规划方法中电网信息与地理信息的脱节,因此存在诸多局限性.结合华东某电网公司电网建设规划需求,设计并实现了基于GIS的电网辅助规划平台.首先描述了电网规划平台的特点以及对系统需求,从方便用户操作和满足规划用户需求的角度,给出了规划平台的系统架构,然后给出了关键模块的解决方案,最后示范了系统应用.     

Strategic behavior in electric generation markets via dynamic governor control design

Previous work has demonstrated the potential for coordinated control of a group of generators in a generation market, with the goal of destabilizing other machines in the system, while maintaining (nearly) completely satisfactory performance within this control group. Such action would clearly achieve an anti-competitive objective, and might be attractive strategic behavior if the entities involved believed it would go undetected. The work here examines the degree to which, among all competing generators, a subset may be specifically `targeted' to experience instability. It refines the earlier design technique to demonstrate that anti-competitive control can indeed selectively target competing generators. This form of strategic behavior will be termed `predatory control.' The results presented suggest that the risk of predatory control is more severe than earlier analysis might have suggested, and provides a cautionary note to indicate that entities responsible for system security must have tools to guard against such behavior.     

基于网络状态信息的车载网功率控制方法

针对车载自组网中,节点密度较高时,容易出现网络拥堵的情况,提出了一种动态调整消息发射功率的方法.通过信道忙闲比例(CBR)评估节点的网络状况,并在出现网络拥堵时泛洪广播拥堵信息,通知其他节点作出相应的功率调整.综合考虑功率覆盖范围和覆盖节点数两方面因素,设计了功率调整曲线.实验结果表明:方法能根据网络状况自适应地调整发射功率,降低了发生信道过载的可能性,并提高了信标消息传递的成功率.     

基于大数据的电网规划精益分析平台研究与应用

随着新能源的大量接入和用户的广泛参与,电网企业的数据呈指数级增长,电网规划部门迫切需要运用大数据的分析手段提高规划决策的精准性。本文以地市供电公司的实体业务为切入点,基于地理位置信息,在数据融合贯通的基础上,运用数据可视化技术多维度动态展示地区电网负荷分布和电网供给能力,辅助规划人员快速发现负荷分布规律和电网薄弱点。运用大数据分析挖掘方法构建基于负荷特性分析的负荷预测模型,支撑电网项目和运行方式安排。打破电网负载问题的单一评价方法,建立可度量的电网综合评价体系及模型,为电网项目统筹提供量化依据。基于大数据的电网规划精益分析平台通过电网负荷可视化展示,有效提升了电网诊断分析效率,运用大数据分析方法提高了地区最大负荷的预测精度,实现了电网问题的数字化评估,提高了电网规划投资决策的精准性。