无锡地区采用高效照明节电技术的成本效益分析

高效照明节电技术作为电力需求侧管理(DSM)的一种技术手段可以起到削减高峰负荷、改善电网负荷特性、提高供电可靠性的作用。在对无锡地区采用高效节电技术调查研究的基础上,分别从电力公司、用户和社会3个方面进行了成本效益分析,为无锡地区实施绿色照明工程提供了理论依据和技术指导。     

基于超效率DEA的火力发电企业能源效率研究

在全要素能源效率框架下建立超效率DEA模型,对河北省13家大型火电企业的全要素能源效率进行了测算和排序,分析了各企业的节能空间,同时基于Malmquist指数对各企业在2009—2011年间的效率变动进行了测算和分解。结果表明:样本期间河北省13家火电企业全要素能源效率稳步提升,但企业间效率差距逐渐加大;火电企业的节能潜力较大,在现有技术水平下,各企业平均每年能源消耗仍有10%以上的可降空间;Malmquist指数分解结果表明技术进步是推动全要素能源效率上升的主导力量。在实证分析的基础上,对提升火电企业的能效水平提出了政策建议。     

Pseudo bond graph model of thermal transfers sustained by ice quantity of a domestic refrigerator for energy saving application

This paper presents a study on the use of ice to improve the energy efficiency of a domestic refrigerator by applying a pseudo bond graph model that describes the thermal transfers sustained by a quantity of ice introduced inside the cavity of refrigeration. The use of ice resulted in a global energy saving of 4.68%. The effect of ice was found to be more significant during the transitional regime. It reduced the response time to reach the stable average temperature from 15 h to only 3.5 h compared to when not using ice. This achievement did not cost additional electrical power, but rather allowed a saving of electrical energy of 76.73%. However, during the steady state, a reduction in the energy efficiency was noted. An improvement in the cooling by keeping the temperature inside the refrigerator more homogeneous is also proved. The model has two inputs: the outside temperature, and the modulated temperature of the evaporator. This latter determines the functioning of the compressor cycle. The model describes the thermal transfers by natural convection inside the refrigerator. Two experiments were carried out to make a performance comparison and to prove the influence of ice in cooling and energy saving. We used real measurements to modulate the evaporator temperature source in the pseudo bond graph model. The simulation results show the effectiveness of the proposed approach. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Power factor correction using magnetic energy recovery current switches

In this paper, we propose a Magnetic Energy Recovery Switch (MERS). The switch consists of four MOSFET elements and one capacitor. A power factor improvement is automatically possible regardless of the impedance and power frequency of the load by synchronized switching of MERS with a power supply. MERS itself generates voltage and compensates for the inductance voltage unlike a conventional series capacitor, so that another DC power supply is not needed. An experiment was carried out to demonstrate the automatic correction of the power factor. We can also expect energy saving of electromachines such as an electric motor by the power factor correction with MERS. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 160(3): 56–62, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20321     

鸭溪电厂1号炉电除尘电气控制部分节能改造

2009年初,鸭溪电厂以改造换节能、以节能换效益,对1号炉电除尘的电气控制部分进行节能改造,将电场电压的控制方式由原火花放电控制方式改成间歇脉冲供电方式,改造后进行节能测试,节能效果达70％,为燃煤电厂电除尘节能改造的走出了一新路,为将来其它燃煤电厂项目作出节能示范,值得推广应用。     

Forecasting electric power generation in a photovoltaic power system for an energy network

Recently, there has been an increase in concern about the global environment. Interest is growing in developing an energy network by which new energy systems such as photovoltaic and fuel cells generate power locally and electrical power and heat are controlled with a communication network. We developed the power generation forecast method for photovoltaic power systems in an energy network. The method makes use of weather information and regression analysis. We carried out forecasting power output of the photovoltaic power system installed in Expo 2005, Aichi Japan. As a result of comparing measurements with prediction values, the average prediction error per day was about 26% of the measured power. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 167(4): 16–23, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20755     

考虑信息间隙决策的能源枢纽混合储能容量规划

针对电池储能等常规储能不能快速响应能源枢纽风电出力短期扰动问题,本文将混合储能引入能源枢纽当中,考虑混合储能在枢纽运行中的损耗,提出了能源枢纽日运行成本最优时的储能容量规划模型。然后基于信息间隙决策理论(information gap decision theory,IGDT)在风险规避策略与机会寻求策略下,建立考虑风电出力不确定性的鲁棒与机会模型,为决策者提供能源枢纽容量规划方案。最后通过算例分析,证明使用混合储能的能源枢纽对风电出力存储转化效率更高,日运行成本更少。同时基于IGDT的混合储能容量规划模型,能够为决策者提供在满足预期运行目标时风电出力最大/最小波动范围,分析风电出力不确定性与混合储能容量之间的关系,通过定量分析为不同风险偏好策略提供容量规划依据。     

余冷回收热泵热水机组技术经济分析

热泵技术是一种提高能效的实用技术,有着广阔的应用前景。介绍了余冷回收热泵热水机组的系统构成、工作原理以及3种模式的运行特性,并对其节能效果与其他热源设备进行对比和分析。结果表明,该机组具有明显的节能效果,并且由于其具有蓄能特性,可以在一定程度上缓解夏季电力供应的压力,有效转移高峰负荷。     

电能计量在110 kV主变降耗中的作用

供电企业在节能降耗中应当主动承担社会责任。通过加强电能计量数据分析．指导和捧动电网设备节能改造,提高电网经济运行水平和企业经济效益。以计量数据分析在降低110kV主变运行损耗的节能改造的应用为例．说明电能计量在节能降耗中的积极作用。     

电动机调速在厂用电节能中的应用

降低厂用电率和降低煤耗是火力发电厂降低发电成本的两大主要技术措施,而厂用电的主要负荷是泵和风机的电动机。以实例阐述了厂用电动机采用调速节能降耗措施的方法和显著效果。     

A Power Control Method to Save Energy for Wayside Energy Storage Systems in dc‐Electrified Railway System

The introduction of wayside energy storage systems is effective for the recovery of regenerative brake energy in dc‐electrified railways. However, considering the cost of their deployment, it is preferable to maximize the energy saving effect with a minimum capacity of the energy storage devices (ESDs). In this paper, we propose a power control method that can improve the energy saving effect while managing the energy of the ESDs. The proposed method is implemented by controlling the filter capacitor voltage of the line side of the power converter for the ESDs depending on their energy and the line voltage of the overhead contact line to which they are connected. Next, the proposed method is verified by numerical simulations and experimental tests with a 1 kW class downsized model.     

An operational algorithm for residential cogeneration systems based on the monitored daily‐basis energy demand

Residential cogeneration systems with PEFC are promising as distributed power system resources with the ability to improve energy system efficiency. However, it is important to develop an efficient algorithm for operation because the energy demand at each house differs greatly from day to day. In this paper, we propose an operational algorithm and evaluate it from the viewpoint of energy conservation and economic effectiveness based on the energy demand characteristics. In the algorithm, the hot water and electricity demand on the next day are estimated based on the average of past data. The results of simulations using actually monitored energy demand data indicate that (1) the greater the electrical demand of a household, the more effective this algorithm becomes with respect to energy conservation; (2) the greater the hot water demand of a household, the more effective this algorithm becomes with respect to economic effectiveness. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(2): 37–45, 2010; Published online in Wiley InterScience ( www.interscience.wiley. com ). DOI 10.1002/eej.20892     

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     

考虑消纳水平的新能源配套储能和输电通道容量协调优化配置

随着以风光为代表的可再生能源发电比例迅速提升,风电场、光伏电站出力的不确定性和波动性给电力实时平衡带来了极大的挑战,配置合理规模的储能可以保障经济性并提高新能源利用率。为此,针对容量已知的新能源电站,提出了一种配套储能和传输线路容量协调优化配置的机会约束规划模型,以储能和传输线路建设成本最小化为目标,以年新能源弃电率不超过规定的指标为机会约束。由于机会约束非凸且缺乏显式表达,基于条件风险价值将机会约束对应的可行域保守转换为线性约束,得到易于求解的线性规划问题,并量化分析了规划方案对新能源场景概率分布的鲁棒性。算例分析结果表明,所提规划模型可以有效地解决考虑新能源消纳能力的储能和传输线路容量配置问题,通过合理配置储能可以降低传输线路的容量从而节约总投资成本。     

节能调度与经济调度的异同分析

节能调度是指在保障电力可靠供应的前提下,按照节能、经济的原则进行电力设度;经济调度是指在考虑全系统经济性的前提下,既考虑机组的最佳组合并经济地分配各发电厂的有功负荷,又考虑电力网线损坏,使得在相同的产出条件下力求能源消耗最少。重点分析了节能调度与经济调度的异同。最后指出,在经济调度机制比较成熟,节能降耗目标实现到一定程度的时候再引入市场定价,这样将进一步促进资源的优化配置。     

节能变压器结构和特点

电网损耗占供电容量7.7%,而变压器损耗占其中大部分,因此采用节能变压器是节能工作的重大措施。降低变压器损耗可从降低铜损、铁损、杂损,消除"大马拉小车",提高运行性能着手,采取改进材质、改造部件结构、使工作原理与工作特性相适应等措施。介绍了超导、非晶、卷铁心、R型卷铁心、立体铁心、单相柱上、调容量、有载调压、中阻抗除尘、低压节电器、铜铁损耗比适配、采用细磁畴高导磁硅钢片、低阻低损导线等13种节能变压器的原理、结构、特点并加以对比。如措施组合,节能会更多。指出S7、S9、S11系列变压器的损耗比较适宜单班制生产,对连续负载和农村负载并不节能。     

某天然气分布式能源冷电联供节能计算与经济性分析

分布式能源联供系统与传统分供系统相比节能率高、环境污染少,是实现节能减排目标的重要途径之一。结合某天然气分布式冷电联供数据中心项目,计算分析了联供系统的一次能源利用效率、节能率、供电效率、供电煤耗、成本回收期,并与分供系统做了对比。结果表明天然气分布式冷电联供系统一次能源利用效率高,供电能耗明显低于发电厂,节能效果非常明显。根据回收期灵敏度分析,联供系统的经济收益和投资回收期限受天然气价格影响较大,当超过一定阈值后,联供系统经济性不如分供系统,所以建造前需充分考虑当地的气价水平。     

Power flow congestion relief by using customer‐side energy storage systems

In recent years, energy storage systems have increasingly been expected as a means of load leveling of the annual load factor. Of course there is an effect of installing the energy storage systems at the substation. But some customers operate their storage system in an integrated way and it also has an effect of increasing the load factor. In this paper the authors proposed that the energy storage systems on the customer side be used for congestion relief on transmission networks. However, it is not clear which kind of customer has the effect of relieving transmission line congestion. First, this paper assumes the authors determine the optimal configuration of energy equipment including energy storage systems. We propose a new contract whereby electric utility subsidizes a part of the entrance cost of the energy storage systems and customers change the output pattern of energy storage according to the request of the electric utility. This paper evaluates the possibility that the contract gives merit to both the electric utility and the customer. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 158(1): 36–45, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20299     

基于熵权可拓模型的火电企业节能减排效果评价研究

为了对火电企业节能减排效果进行科学合理的评价,基于现有评价指标体系构建原则基础上,构建了一套适合火电企业节能减排效果评价体系,运用熵权可拓模型对节能减排效果进行全面、有效的评价.经案例分析证明,该评价体系和熵权可拓模型具有合理性和可行性,使火电企业之间节能减排效果有了可比性,提高了节能减排考核的效率.同时,也为火电企业有效地进行节能减排效果评价提供了参考.     

电力系统综合节能的有功与无功功率协调优化

针对将有功功率与无功功率分开优化的不合理性,将网损以发电费用最小的原则分摊到各个发电机上,建立电力系统综合节能的有功与无功功率协调优化模型.在求解模型时,首先利用梯度法初始收敛速度快的特点将控制变量迅速收敛至最优解域,同时通过节点和支路类型转换处理节点电压和支路潮流越限问题;在最优解附近系统起作用不等式约束集基本确定的情况下,再利用牛顿法的二次收敛特性,求解精确最优解,提高了牛顿法的计算效率.研究结果可以为自动发电控制和自动电压控制系统的协调优化控制提供参考.在IEEE-30节点系统上的仿真结果验证了所建模型和算法的有效性.