A new electric power network for effective transportation of small power of dispersed generation plants

This paper proposes a new electric power network that makes it possible for many types of dispersed generation plants owned by nonutility organizations to participate in an electric power market without the disadvantages of existing power utility and customers. This power network is called an open electric energy network (OEEN) because the network is open to the many types of plants for the participation. For achieving such openness, electric power storage devices, load controller at each customer and data communication network are installed in OEEN; the flow of excess electric power generated by each plant is controlled autonomously and in a distributed way. That is, the control is done by transmitting the data on excess electric power such as generation and demand point, power quality, price, etc., from each dispersed generation plant to the power storage devices and the load controllers through the communication network. Since this data-driven power flow control is similar to the mail system for a packet with the addresses of sender and receiver, it is called packet electric power transportation. In OEEN the storage device plays a different role from load leveling. Therefore, the way to determine the storage capacity differs from the conventional approach. In this paper, the applicability of queuing theory for determining the capacity is also discussed.     

Designing incentive compatible contracts for effective demandmanagement

Demand relief from customers can help a utility (or any “load serving entity”) solve a variety of problems. There exist all sorts of different demand management programs that utilities use. A critical issue is the incentive paid to the customer to participate in demand management programs and provide load relief. The utility has to design cost effective yet attractive demand management contracts. The main goal is to get load relief when needed, and to do so in a cost effective way. Customers sign up for programs when the benefits they derive in the form of up front payments, demand discounts and interruption payments exceed their cost of interruption. In order to design such contracts, mechanism design with the revelation principle is adopted from game theory and applied to the interaction between a utility and its customers. The idea behind mechanism design is to design an incentive structure that encourages customers to sign up for the right contract and reveal their true value of power (and thus, the value of power interruptibility)     

A smart building power management concept: Smart socket applications with DC distribution

Recent developments in power electronics increase DC bus utilization in electrical distribution systems due to its numerous advantages compared to AC distribution system in term of energy efficiency, safety, electromagnetic compatibility and renewable energy integration. This study presents a power management system concept based on domestic DC distribution with smart sockets for future smart houses. Energy efficient smart buildings are possible by integrating smart meter, smart sockets, domestic renewable energy generation and energy storage systems for integrated energy management, and this integrated system supports demand side load management, distributed generation and distributed storage provisions of future smart grids. Coming era of smart grids has implications for domestic DC distribution concepts with smarts sockets. Paper describes use of smart DC sockets as an integral part of building power management automation and presents a load shedding algorithm for plug load control for buildings. Simulations show performance of the proposed system components.     

电力负荷供需矛盾的解决措施分析

详细介绍了为实现科学的负荷管理,缓解电力供需紧张的矛盾,各电力公司以及负责机构可以采用的政策措施、行政措施、技术措施、经济措施以及宣传措施。这些措施都是符合市场经济运行规则的有效手段,是对于社会、电力客户、发电企业、电网企业都有利的举措。     

Using utility information to calibrate customer demand managementbehavior models

In times of stress customers can help a utility by means of voluntary demand management programs if they are offered the right incentives. The incentives offered can be optimized if the utility can estimate the outage or substitution costs of its customers. This paper illustrates how existing utility data can be used to predict customer demand management behavior. More specifically, it shows how estimated customer cost functions can be calibrated to help in designing efficient demand management contracts     

含分布式电源接入的市场多主体博弈分析

研究能源互联网发展背景下含有分布式电源(distributed generation, DG)接入的电力市场中的多主体博弈问题。首先,利用多代理(multi-agents)技术,在由发电商、供电商与多类型用户组成的市场中,搭建了多主体博弈框架。其次,针对该框架下的市场各主体特点,分别采用统一市场出清价格(market clearing price, MCP)和按报价支付(pay as bid, PAB)的市场机制,构建了最优供应函数决策模型、最优投标电价决策模型以及考虑投标风险的最优投标电量决策模型。并且,基于效用函数,考虑弹性负荷(具有分布式发电或可中断能力)用户的购售能力,建立了最优购电和最优DG发电量决策模型。最终,实现了市场各博弈主体的利益均衡化目的。仿真结果表明,基于多代理技术的博弈能实现市场各主体的合理收益,不同主体组合的市场博弈结果存在较明显差异。充分挖掘弹性负荷调节能力可有效提高分布式清洁能源发电渗透率。以上结果符合工程实际与设计需求,验证了所提模型的合理性与有效性。     

在全面开放的电力市场中用户用电管理及其策略

分析了在全面开放的竞争的环境下用户的用电特点、用户成本结构与用户用电成本。传统的环境下,用户对用电没有太多的选择。而在全面开放的竞争的电力市场中,用户将有更多的选择,最主要的是可以选择其电力供应公司（发电公司和配电公司）以及选择电价和服务。不同用存在不同的成本结构。用户用电决定其购电成本,用户用电质量、可靠性等决定其服务成本,用户停电损失决定其停电成本。研究了用户4种基本购电方式。不同的购电方式影响着用户的用电成本。在用户用电成本的基础上深入研究了用户的用电管理以及用户的用电策略。研究结果表明,用户加强用 采取适当的用电策略在一定程度上可以降低用户用电成本。     

电力市场中激励性可中断负荷合同的建模与实施研究

考虑到供电公司的风险偏好,作者应用机制设计理论建立了一种用户类型离散的可中断负荷合同模型.分析和算例结果表明,无论供电公司的风险偏好如何,该合同模型均能引导用户披露真实信息,实现电力资源的有效配置,且供电公司能从中节约供电成本.因此,激励性可中断负荷合同不仅能提高用户需求弹性,还有助于供电公司回避市场风险.尤其是对于风险进取的供电公司,可中断负荷合同将成为其进行市场竞争和风险管理的有力工具.因而所提出的模型为供电公司参与市场竞争提供了一种新的思路.     

Development and testing of an energy saving tool – Suitability analysis with case study

The increasing demand for electrical energy, the depletion of fossil fuel based resources and environmental constraints have made it mandatory for the efficient use of electrical energy, energy saving applications and implementing an energy management program. In this paper, a user-friendly tool for tracking and analyzing the electric bills, suggesting the best electricity tariff, controlling the active and reactive power rates, increasing energy efficiency, allowing the consumer to compare the alternatives and avoiding any penalties is presented step by step. The proposed energy saving tool will also help the electrical and more particularly power engineers and consumers in industrial sector to reduce electricity consumption while maintaining the quality of service. The developed tool is applied and tested to determine the optimal design of electrical power system in a university hospital. Test results reveal the performance of the developed tool for an optimization of commercial and industrial plants under different scenarios of power consumption and load demand. The program is written in the Delphi programming environment XE3 to provide enhanced flexibility and runs on Windows.     

Generation scheduling in smart grid environment using global best artificial bee colony algorithm

Generation scheduling is an important concern of the current power system which is suffering from many obstacles of limited generation resources, grown energy demand and fuel price, inconsistent load demand and fluctuations of available wind power in case of the thermal–wind system. Smart grid system has a great potential of tumbling existing power system difficulties with intelligent infrastructure and computation technologies. Three different distributed energy resources, namely, distributed generation, demand response and gridable vehicles are used in this paper to overcome the power system hitches. The classical generation scheduling is solved with insertion of the cost of demand response and the cost model pertaining to underestimation and overestimation of fluctuating wind power. The modified optimization problem is solved using an efficient Global best artificial bee colony algorithm for 10 generating units test system. Generation scheduling in the smart grid environment yields a significant reduction in the total cost.     

风光氢联合式独立发电系统的建模及仿真

提出了一种独立使用的风光氢联合式独立发电系统，该系统由风力发电、太阳能发电、氢能系统(包括电解水制氢、燃料电池系统、超级电容等)及其他系统单元组成。各单元通过2条直流总线联接，并采用功率流控制。由于风力发电与太阳能发电所输出的功率随风速和日照的变化而变化，因此采用燃料电池系统与超级电容堆与风光发电系统配合使用，以保证系统在任何条件下都具有可靠的供电性能。当风能与太阳能充足时，风机与光伏阵列可满足负荷的需要，同时还可向电解池供电；如果不能满足负荷的需要则由燃料电池提供额外的电能，同时由超级电容在短时期内向负荷提供燃料电池最大功率以外的那部分电能。最后在Matlab环境下建立了系统仿真模型，并以西藏边远村落为例对该系统的动态响应进行了仿真分析，仿真结果表明本文提出的供电系统可以用于以西藏为典型代表的风速和光能变化较大的边远地区。     

A database system for power systems customers and energy efficiency programs

In this paper the design and development of a database for the registration of power utilities’ customers and their energy behavior are described. The database also includes the customers’ devices and buildings, their demand curves, their tariffs, their connection with power and gas networks, as well as the measures of demand side management and energy saving, which can be implemented. The main purpose of this database is to support end-use models and load forecasting algorithms for individual customers or their respective clusters, to study the effects of energy efficiency programs and to evaluate the last ones financially. It can be a useful tool for retailers, distribution electricity companies or regulatory authorities of energy.     

利用电能计量自动化系统开展负荷管理的探索简

介绍电能计量自动化系统在停电管理、配变重过载管理工作中的作用以及该系统在配网规划和业扩报装的辅助作用,阐述该系统利用其庞大的数据量,结合工作经验和实际需要,将其拓展应用到负荷管理工作中,规范了电力需求侧管理,提高了工作效率。     

县级供电企业电力需求侧管理

电力需求侧管理（DSM）引导电力客户改变和优化用电方式,合理配置和使用电力资源,提高客户的终端用电效率,达到节约能源和保护环境,促进电力供需平衡,提高电能使用效率。     

Economic evaluation of demand‐side energy storage systems by using a multi‐agent‐based electricity market

With the wholesale electric power market opened in April 2005, deregulation of the electric power industry in Japan has faced a new competitive environment. In the new environment, Independent Power Producer (IPP), Power Producer and Supplier (PPS), Load Service Entity (LSE), and electric utility can trade electric energy through both bilateral contracts and single‐price auction at the electricity market. In general, the market clearing price (MCP) is largely changed by the amount of total load demand in the market. The influence may cause a price spike, and consequently the volatility of MCP will make LSEs and their customers face a risk of higher revenue and cost. DSM is attractive as a means of load leveling, and has an effect on decreasing MCP at peak load period. Introducing Energy Storage systems (ES) is one DSM in order to change demand profile at the customer side. In the case that customers decrease their own demand due to increased MCP, a bidding strategy of generating companies may be changed. As a result, MCP is changed through such complex mechanism. In this paper the authors evaluate MCP by multi‐agent. It is considered that customer‐side ES has an effect on MCP fluctuation. Through numerical examples, this paper evaluates the influence on MCP by controlling customer‐side ES corresponding to variation of MCP. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 167(3): 36–45, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20658     

Demand-side management in smart grid operation considering electric vehicles load shifting and vehicle-to-grid support

Demand fluctuation in electric power systems is undesirable from many points of view; this has sparked an interest in demand-side strategies that try to establish mechanisms that allow for a flatter demand curve. Particularly interesting is load shifting, a strategy that considers the shifting of certain amounts of energy demand from some time periods to other time periods with lower expected demand, typically in response to price signals.In this paper, an optimization-based model is proposed to perform load shifting in the context of smart grids. In our model, we define agents that are responsible for load, generation and storage management; in particular, some of them are electric vehicle aggregators. An important feature of the proposed approach is the inclusion of electric vehicles with vehicle-to-grid capabilities; with this possibility, electric vehicles can provide certain services to the power grid, including load shifting and congestion management. Results are reported for a test system based on the IEEE 37-bus distribution grid; the effectiveness of the approach and the effect of the hourly energy prices on flattening the load curve are shown.     

Stochastic operational scheduling of distributed energy resources in a large scale virtual power plant

Virtual Power Plant (VPP) is introduced as a tool for the integration of distributed generations, energy storages and participation of consumers in demand response programs. In this paper, a probabilistic model using a modified scenario-based decision making method for optimal day ahead scheduling of electrical and thermal energy resources in a VPP is proposed. In the proposed model, energy and reserve is simultaneously scheduled and the presence of energy storage devices and demand response resources are also investigated. Moreover, the market prices, electrical demand and intermittent renewable power generation are considered as uncertain parameters in the model. A modified scenario-based decision making method is developed in order to model the uncertainties in VPP’s scheduling problem. The results demonstrated that the optimal scheduling of VPP’s resources by the proposed method leads VPP to make optimal decisions in the energy/reserve market and to play a dual role as a demand/generation unit from the perspective of the upstream network in some time periods.     

京津唐电网负荷特性分析及预测

关注分析经济发展水平与能源分布对电网负荷特性的改变,将有助于调整与制定相应的用电计划,合理调度发电,降低发电成本,确保安全可靠供电。分析了2005—2013年京津唐电网电力消费特点及负荷的年度变化趋势和月度规律,并对夏季典型日和冬季典型日进行了分析。进一步的,结合国家政策的变化和调整,对2014—2016年电力需求及负荷特性进行了预测,为有序用电、需求侧管理以及制定节能减排政策等提供参考。     

引入可中断负荷的新型阻塞管理研究

传统的阻塞管理从发电侧调整机组出力消除阻塞,但调用高价电能消除阻塞使电网的购电成本较高.文章通过可中断负荷应用于阻塞管理的可行性分析,提出了引入可中断负荷的新型阻塞管理模式,并阐述了该模式下电网总体购电成本的计算方法.3节点算例表明该新型阻塞管理模式下电网的购电成本更低.     

Preliminary Feasibility Study on Application of Very Large Scale-Photovoltaic Power Generation in China

Solar energy photovoltaic power generation is hopeful to be applied in a large amount and possesses a certain proportion in the structure of energy in the future. In this paper, based on the forecasting of electric load demand and energy structure of power generation in the middle of 21 century, the pictures of VLS-PV power generation is composed, the operation characteristic of VLS-PV power generation and the adaptability of electric power grid for it is analyzed, the ways for transmitting large amount of PV power and the economic and technical bottlenecks for applying VLS-PV power generation are discussed. Finally, the steps and suggestions for developing VLS-PV power generation and its electric power system in China are proposed.