Evaluation of Residential PV‐EV System for Supply and Demand Balance of Power System

In recent years, there has been a growing interest in ecofriendly technologies such as residential photovoltaic (PV) systems and electric vehicles (EVs). PV systems and EVs will contribute to reducing CO₂ emissions in the residential sector and the transportation sector, respectively. In spite of that, high penetration of PV systems into the power grid can cause grid voltage and frequency stability problems. Also, the growth of the EV market will create an extra electricity load (for charging the EV fleet), leading to an increase in power utility fuel costs. In this research, we proposed the usage of the PV‐EV system as a method of mitigating the impact the spread of residential PV systems and EV on the power grid. We built an PV‐EV system simulation model and investigated the PV‐EV system contribution to the balance of power supply and demand and to reducing the total cost of the household under different electricity pricing scenarios. We also evaluated the effect of uncertainty in the forecasting of load and PV output on the performance of the PV‐EV system.     

计及实时电量交易的售电公司日偏差电量考核优化模型

启动现货市场的目的是建立电力中长期交易和现货交易相结合的市场化电力电量平衡机制,而在市场运营机制不完善的建设初期,以日为结算期的短期考核机制有利于市场公平交易,稳定现货市场中的电力电量波动。为了更直观地体现短期偏差电量考核对售电公司收益及经营策略的影响,构建了计及日偏差电量考核机制的售电公司日前市场收益模型。基于实时市场购电和与储能电站电量交易,建立了以售电公司收益最大化为目标的日偏差电量考核优化模型。基于广东省2017年交易数据模拟典型日现货交易和实际用电情况,对比分析模型优化效果,并对统一出清价和单位考核成本及与储能电站的交易电价、正、负偏差量进行了敏感性分析。结果表明：该优化策略可明显提高售电公司收益;统一出清价、单位考核成本和向储能电站购电电价对额外成本影响最大,向储能电站售电电价对额外收益影响最大,正、负偏差量对售电公司整体收益影响最大。     

基于双层随机规划的电力零售商短期决策模型

以风和光伏为代表的分布式可再生能源逐渐参与了电力现货市场的交易,针对分布式可再生能源出力不稳定的特点,提出了一种电力零售商短期决策模型。首先阐述了分布式可再生能源市场及双层随机规划模型框架;然后将双层随机规划模型转化为等效的单层混合整数线性模型,在此基础上考虑了日前市场和实时市场的电价、分布式可再生能源产量、电力需求和电力零售商与其它负荷服务商报价的随机性;最后,通过实例分析验证了该模型的有效性。     

Experimental Services of Energy Management for Energy Users in Business Region on Miyakojima City All‐Islands EMS Demonstration Project

Smart grid and demand response (DR) had been attracting attention and evaluated in several demonstration projects. Many DR experimental results for residential and large‐scale buildings had been evaluated, while evaluation for small size buildings seems to be not enough. In this paper, a new energy service combined EMS method is proposed for small size buildings. Then results of its application to Miyako Island All‐Islands EMS Demonstration Project are introduced. The experimental services include not only DRs but also peak cutting recommendations and energy analysis reports. The results show combination of services can realize more effects than individual service. Especially the peak cutting recommendations and energy analysis reports help energy consumers to learn and understand how to save and manage energy usages that lead to effective DR potentials. Also the experimental system developed for energy data measurement and DR management as an island community EMS is intrduced.     

基于非完全信息Stackelberg博弈的居民用户分时电价定价策略研究

随着我国售电市场规模的扩大以及用户响应能力的提升,基于用户响应准确建模的售电公司售电定价策略受到广泛关注。针对居民用户分时电价定价问题,提出了居民用户转移负荷满意度成本系数的辨识方法,考虑转移负荷满意度成本系数的概率分布,建立了售电公司与居民用户的非完全信息Stackelberg博弈模型,售电公司以购售电收益期望最大化为目标,各种典型场景下居民用户均以综合效用最大化为目标。通过算例分析验证了所提策略对售电公司收益的提升,并分析了现货市场电价对售电公司定价决策的影响。     

Impact of demand response resources on unit commitment and dispatch in a day-ahead electricity market

Demand response (DR) has recently become an important resource in both system operation and market operation. The focus of this paper is to investigate and quantify the cost impact of various demand response modelings on unit commitment and dispatch in a day-ahead market regime. We have used mixed integer programming unit commitment model, in the market operation framework. Day-ahead market is modeled with a typical test system. Our research results show that DR can exert downward pressure on electricity prices, causing significant implications on social welfare. Results from this work will help policy makers, resource planners, and market designers to make more informed decisions with the goal of better accommodating more demand response resources in the future.     

区块链环境下考虑信用的需求响应资源交易机制

需求响应(DR)资源参与电网互动丰富了电网调度的手段,然而,由于DR资源的不确定性且个体趋利性难以直接控制,相较于传统电力资源,其交易的违约概率更大,使得结算与惩罚机制复杂化.为有效引导需求侧资源积极参与响应,降低违约风险,从而提高DR参与调度的可用性,提出了基于区块链的DR资源信用管理方法,分别搭建了集中交易和双边交...     

基于用户负荷特性的电价交叉补贴测算模型

妥善处理电价交叉补贴是输配电价改革的关键,对中国新一轮电力市场化改革的顺利推进至关重要。综合考虑中国输配电价改革和各电压等级各类电力用户的负荷特性,构建各电压等级各类电力用户电价交叉补贴测算模型并以中国北方某省为例进行实证测算与分析。结果表明：该省居民生活用户和农业生产用户为交叉补贴享受方,其中居民生活用户享受的交叉补贴最多,占这两类用户享受的交叉补贴总额的92.84%;大工业用户和一般工商业及其他用户为交叉补贴提供方,其中大工业用户提供的交叉补贴最多,占这两类用户提供的交叉补贴总额的51.59%;电压等级越低,居民生活用户和农业生产用户享受的电价交叉补贴程度越大。     

New secure bilateral transaction determination and study of pattern under contingencies and UPFC in competitive hybrid electricity markets

In the competitive electricity environment, the flexibility of power transactions is expected to drastically increase among the trading partners and can compromise the system security and reliability. These transactions are to be evaluated ahead of their scheduling in a day-ahead and hour-ahead market to avoid congestion and ensure their feasibility with respect to the system operating conditions. The security of the transactions has become essential in the new environment for better planning and management of competitive electricity markets. This paper proposes a new method of secure bilateral transaction determination using AC distribution factors based on the full Jacobian sensitivity and considering the impact of slack bus for pool and bilateral coordinated markets. The secure bilateral transactions have also been determined considering critical line outage contingencies cases. The bilateral transaction matrix pattern has also been determined in the presence of unified power flow controller (UPFC). The optimal location of UPFC has been determined using mixed integer non-linear programming approach. The proposed technique has been applied on IEEE 24-bus reliability test system (RTS).     

Participation in the Illinois solar renewable energy market

Opportunities for Illinois residential electricity consumers to participate in the renewable energy market will expand considerably as a result of the recently enacted Future Energy Jobs Act. These opportunities range from proactive options, such as installation of one’s own solar array, to passive ones by which most Illinois residential electricity consumers will participate minimally by law simply by being an electric customer of a public utility.     

Potential evaluation of energy supply system in grid power system,commercial, and residential sectors by minimizing energy cost

If the economic activity in the commercial and residential sector continues to grow, improvements in energy conversion efficiencies of energy supply systems is necessary for CO₂ mitigation. In recent years, the electricity driven hot water heat pump (EDHP) and the solar photovoltaic (PV) have been commercialized. The fuel cell (FC) of co‐generation system (CGS) for the commercial and residential sector will be commercialized in the future. Copyright © 2004 Wiley Periodicals, Inc. The aim is to indicate the ideal energy supply system of the users sector, which manages both the economical cost and CO₂ mitigation, considering the grid power system. In this paper, cooperative Japanese energy supply systems are modeled by linear programming. It includes the grid power system and energy system of five commercial sectors and a residential sector. The demands of sectors are given by the objective term for 2005 to 2025. Twenty‐four‐hour load for each three annual seasons are considered. The energy systems are simulated to minimize the total cost of energy supply, and to mitigate the CO₂ discharge. As a result, the ideal energy system at 2025 is shown. The CGS capacity grows to 30% (62 GW) of the total power system, and the EDHP capacity is 26 GW, in commercial and residential sectors. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 160(2): 9–19, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/ eej.20361     

计及负荷规模效应的售电公司决策研究

负荷规模对售电公司的市场参与和盈利起着重要作用。从规模经济学的角度分析了售电公司负荷规模对其经营成本和盈利能力的意义;然后考虑一定规模的售电公司与发电市场的相互作用,构建详细的购电价格模型,并基于心理学模型建立售电价格与负荷规模的关系。在此基础上,考虑市场价格与需求的不确定性,应用随机规划理论构建售电公司决策模型,以实现单位负荷的利润最大和风险最小化。模型构成的EPEC(Equilibrium Problem With Equilibrium Constraints)问题,采用敏感度函数法迭代求解。算例结果表明,该算法可以有效收敛,且售电公司的规模对降低单位购电成本具有经济效益。     

售电市场环境下基于数据驱动的用户用电行为分析

智能电能表能够实时采集用户的用电数据,在未来数字化配用电系统中将得到广泛普及。在我国售电市场进一步放开并逐步繁荣的背景下,售电商能够通过分析海量用户用电数据,掌握用户用电行为,从而实现更好的服务。探讨了面向售电市场用户行为分析的特征提取方法,采用了k-means、模糊聚类、层次聚类等不同的聚类算法实现典型用户用电行为的模式提取,分析了不同用户用电行为的基本特征。对爱尔兰地区6 445名用户的公开用电数据进行实证分析,结果表明,该方法能够有效提取用户的用电行为模式,分辨用户用电行为异同。     

可再生能源消纳责任权重制下电力市场优化决策模型

可再生能源消纳责任权重制与电力现货市场建设并行推进,实际消纳可再生能源电力将成为电力用户完成考核要求的主要完成方式,并且可再生能源电力也将逐步进入电力现货市场参与交易。基于以上框架建立了可再生能源消纳责任权重制下包含可再生能源日前市场、常规能源日前市场、实时市场的双层多主体优化决策模型,通过库恩-塔克(KKT)条件、强对偶定理、二进制拓展法等方法将其转化为混合整数线性规划模型来求解市场均衡点。算例分析探究了考核权重指标、绿色电力证书价格、可再生能源功率渗透率对市场均衡点的影响。分析结果表明,在市场均衡点日前市场中,可再生能源电力出清电价等于常规能源出清电价加上绿色电力证书价格,且随着可再生能源功率渗透率提高,电力现货市场出清电价呈现下降趋势。     

Operation and economy of a refuse‐fired generating system with electricity wheeling service

Electric power markets have been partially liberalized and liberalization will be proceeding steadily. On the other hand, refuse‐fired generating systems (RGS) are constructed in many municipal corporations as on‐site power sources. This paper discusses the operation of an RGS which can transfer its excess energy to consumers through the electricity wheeling service of the electric utility. The RGS is operated by the dynamic programming method under the constraints of RGS operation and electricity wheeling service. In the DP method, the estimation function is the annual total electricity charge of both the RGS and the consumers, and the control variable is the residual amount in the refuse pit. A university, hospitals, welfare apartment houses, and their combinations are selected as consumers. The main results obtained are as follows: (1) electricity wheeling service is more economical than the absence of electricity wheeling service when the annual demand of the consumer is higher than 70% of the excess energy of RGS; (2) it is more economical as the load factor increases if the annual demand is the same; (3) the most economical consumer is the combination of four hospitals and five welfare apartment houses, for which the total electricity charge can be reduced to 84% of that in the absence of wheeling service. It is concluded that the total electricity charge of the RGS with electricity wheeling service could be decreased considerably by selecting the consumers appropriately. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 146(1): 59–69, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10211     

A development of an equilibrium analysis model between electricity retailers under competitive environment

This paper provides a novel equilibrium model for analyzing behaviors of the electric retailers under competitive environment. In the deregulated electricity retail market, the retailers purchase the electricity power and sell it to consumers at the competitive prices. According to their risk attitudes, the retailers optimize the selling prices and the purchase allocation between a day‐ahead market and forward contracts. Without the regulation, an equilibrium by those selfish decision‐making processes of multiple retailers would cause an adverse impact on the electricity market and also the power system. From stable and economical viewpoints, it is important to analyze the unfavorable equilibrium. The selfish behaviors of retailers are modeled as an equilibrium problem with equilibrium constraints in this paper and formulated as a mixed integer linear programming problem to obtain a generalized Nash equilibrium by commercial solvers efficiently. Through computational examples, the proposed model and formulation are validated.     

An annual framework for clustering-based pricing for an electricity retailer

In the competitive environment, it is necessary for a retailer to increase his/her profit as much as possible. There are few researches focused on the subjects related to the retailer and the retail market. In addition, those researches have mostly focused on the participation of the retailer in the wholesale market. In order to determine the optimal selling price, the knowledge of how and when consumers use electricity is essential to the retailer. This type of information can be found in load profiles of customers. In this paper, an annual framework for optimal price offering by a retailer is proposed which is based on clustering technique. For this purpose, load profiles of customers are used as their consumption patterns. Also, a profit function is defined as the objective of optimization problem based on the load profile considering conditional value at risk (CVaR) for risk modeling. Also, a new acceptance function is proposed to overcome drawbacks of the traditional ones. The objective function is a mixed-integer nonlinear problem which is solved by GAMS software.     

基于交流灵敏度的电能交易与输电权的统一拍卖

最优潮流程序便于实现线路有功功率和有功网损的交流灵敏度的计算和分析,且基于交流灵敏度信息的输电权计算可以更好地匹配实际潮流,故采用交流灵敏度信息作为市场交易的依据。同时,简化的市场结构可以降低电力市场交易成本和提高市场交易效率,由于电能交易同输电权交易具有相同的市场拍卖形式,因此以交流灵敏度信息为基础,建立了点对点输电权、基于潮流的输电权和电能交易的统一拍卖市场。提出的拍卖模型在数学上是一个线性规划问题,可以利用成熟的线性规划方法进行解算。这种统一市场实现了电能交易与输电权交易的全面优化,也为市场参与者在同一市场下提供了更多的选择。IEEE9节点算例证明了该方法的有效性。     

大用户控制购电成本风险的均值–熵权组合优化模型

大用户直购电是电力大用户和发电公司直接进行双边交易的一种购电模式,其主要目标是购电成本最小化,因此需要从现货市场、长期合约市场和期权市场中进行组合优化购电,从而控制购电成本风险。考虑到风险具有不确定性,引入连续信息熵作为大用户购电组合风险度量因子,以风险最小化为控制目标,基于投资组合理论,构建大用户在3个交易市场中的购电组合优化模型,并采用Matlab编程进行求解。算例结果表明,文中的熵权组合模型具有合理性,可为确定大用户购电决策提供参考,同时也说明期权市场可以有效减少大用户的购电风险,期权价格和敲定价格对大用户购电决策的影响较大。     

Demand Response: Reality versus “Resource”

Excessive enthusiasm for DR is driven largely by the illusion that increasing DR creates large benefits for consumers in the form of lower prices and the confusion created by referring to DR as a “resource” that should be treated just like supply resources in some undefined sense. DR should be implemented using standard market concepts and processes.