中国煤电产能是否过剩的探讨

从中国电力供需矛盾在新常态下发生重大转折的主要特点出发,分析了近年电力供应侧、需求侧发展特点,从“数量”与“质量”、不同主体的价值观、市场机制、国际比较等方面对煤电是否过剩进行了分析,提出电力负荷结构调整、电力需求总体不足、电力结构变化较大、煤电调峰任务加大、煤价持续下降、煤电经济效益较好等是造成煤电产能相对过剩的原因。提出了从电力供给侧和需求侧两方面要约束新增电力产能;建议促进煤电功能转变、挖掘现有煤电机组能力、提高燃煤机组深度调峰能力、避免过度“上大压小”等;建议在需求侧方面等待电力需求恢复、主动扩大用电需求、通过碳市场建设抑制煤电产能等措施。并提出了在能源系统优化的模式下,煤电将有10个百分点左右的设备利用率潜力可挖,“十三五”期间煤电可有3亿t左右原煤产能的转化能力。     

Influence of forecast accuracy of photovoltaic power output on capacity optimization of microgrid composition under 30‐minute power balancing control

A microgrid (MG) is one of the measures for enhancing the high penetration of renewable energy (RE)‐based distributed generators (DGs). If a number of MGs are controlled to maintain the predetermined electricity demand including RE‐based DGs as negative demand, they would contribute to supply–demand balancing of the whole electric power system. For constructing an MG economically, capacity optimization of controllable DGs against RE‐based DGs is essential. Using a numerical simulation model developed on the basis of a demonstrative study on an MG using PAFC and NaS battery as controllable DGs and photovoltaic power generation system (PVS) as an RE‐based DG, this study discusses the influence of the forecast accuracy of PVS output on capacity optimization. Three forecast cases with different accuracy are compared. The main results are as follows. Even with no forecast error during every 30‐minute period, the ideal forecast method, the required capacity of NaS batteries reaches about 40% of the PVS capacity for mitigating the instantaneous forecast error within 30 minutes. The required capacity to compensate for forecast error is doubled under the actual forecast method. The influence of forecast error can be reduced by adjusting the scheduled power output of controllable DGs according to weather forecasts. Besides, the required capacity can be reduced significantly if the error of balancing control in an MG is acceptable for a few percent of periods, because the total periods of large forecast error are not frequent. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 182(2): 20–29, 2013; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22328     

Optimal operation of cogeneration system coordinated by aggregator for providing the demand and supply regulation capacity

Recent growth of renewable energy generations with natural variability, such as photovoltaic generation and wind turbine generation, would make the demand and supply control in a whole power system more difficult, and therefore, alternatives for demand and supply regulation resources would be required. The authors focus on cogeneration system (CGS) as one of regulation resources. In order to procure adequate volume of regulation capability, an aggregator coordinates a number of CGSs efficiently and flexibly considering the wide variety of electricity/thermal demands of CGS owners. This paper proposes a novel optimal operation strategy of CGS coordinated by the aggregator considering the energy balance and operation cost of individual CGS owner. This paper also demonstrates the availability of CGSs for regulation capability by numerical case studies in which the actual consumption profile is employed.     

Evaluation of the reduction in CO2 emissions by applying Micro‐Grid to home energy supply system

Dispersed generators such as wind power systems, photovoltaic systems, and cogeneration systems are expected to mitigate the environmental burden of energy consumption, and their installation has been promoted recently. Micro‐Grid is focused on as a method to solve some problems in a commercial electric power line when installing a large number of dispersed generators, and some demonstrative research on Micro‐Grid for large‐scale systems is being carried out now. Also, small cogeneration systems for houses, such as gas engines and fuel cells, are expected to improve CO₂ emissions. However, if the power and heat demand of a family are relatively small or are unbalanced, the cogeneration system does not operate effectively. The authors have studied the application of Micro‐Grid for home energy supply, and have developed a control system to solve this problem. The system achieves a reduction of CO₂ emissions and energy costs by sharing electric power and heat among some houses with cogeneration systems. This paper presents an outline of the newly developed system, and in particular describes the effect of the reduction in CO₂ emissions compared with a conventional energy supply method, and the case in which dispersed generators are installed in some houses and operate independently. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(3): 19–27, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20879     

A local demand forecast by NN method for distributed autonomous voltage and reactive power control system

The paper describes required technological innovation for voltage control of power systems under deregulation of power supply industries and presents a new concept of an autonomous control system for the voltage and reactive power of power systems. Installation of distributed generation connected to distribution networks will significantly increase the short circuit capacity of distribution lines. Therefore, GIS underground substations in the center of a large city are required to enable replacement of circuit breakers with ones of greater capability and to reform GIS bus configurations. Furthermore, a more detailed forecast of local demand and operation data of distributed generators are required for the stable control of voltage and reactive power. This paper presents methods of on‐line autonomous forecasting for short circuit capacity and demand of local transmission and distribution lines, which are indispensable for voltage and reactive control under deregulation of electric power supply industries. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 159(4): 27–37, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20450     

基于新能源的电力经济调度分析研究

随着全球对新能源需求的日益增长,风能、太阳能等新型能源得到了广泛的关注,逐渐成为能源体系的重要组成部分,但是由于其随机性、间歇性的特点,也对电力系统的稳定运行产生了影响.本文将新能源引入到电力系统经济调度中,搭建了基于多种能源组合的电力系统经济调度模型,将新能源容量引入到电力系统经济调度的成本控制函数中.对调度模型进行...     

Load‐following control for dispersed generators using a PI controller

Recently, there has been growing interest in utilizing dispersed generation systems, which are grouped into micro turbine systems, co‐generation systems, and so on, as a substitute for fuel oil energy and a technology to prevent global warming. Since start‐up time of dispersed generation systems is short, it is possible to operate systems to supply load power corresponding to a demand. Moreover, PPSs (Power Producers and Suppliers) can participate in a power retail sales company, since deregulation of electric utilities was instituted in March 2000. However, PPSs have to keep instantaneous generating power commissioning rule, to maintain supply‐and‐demand balance between customer and supplier. Therefore, in this paper, we examine instantaneous generating power commissioning for dispersed generators where start‐up time is short and it is possible to operate systems to supply a power load corresponding to a demand. We adopt a PI controller as a controller. The system is composed of double control loop in inner loop and in outer loop. In inner loop electric power is controlled and in outer loop electric energy is controlled. The controller parameters are designed using the pole‐placement technique. The effectiveness of the proposed control system is confirmed by simulations. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 145(2): 58–66, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10200     

Method to estimate long‐term change of heat and electric power daily load curves in Japan

The rapid spread of CHP systems will put pressure on the regional power system to require an examination of the power and heat output of CHP systems. When considering the countrywide potential of the CHP system, one should examine such a system in coordination with the grid power system. It is essential to calculate the heat and power demand at end‐use level. In this paper, annual heat and power demands of end‐use sectors are forecast to the year 2025 based on 20‐year data. Regression analysis is used. Estimated annual demands are divided into the seasonal hourly demands considering demand characteristics. Daily load curves of heat and power demands are determined for the Japanese end‐use sectors, and the annual changes of such demands are shown by duration curves of heat‐to‐power ratios. Moreover, the grid power daily load curves are computed numerically from the estimated heat and power demands for the manufacturing, residential, and commercial sectors. Such load curves also consider self‐generated power for the manufacturing industry and self‐consumption of the grid power. Estimating heat and power demands allows for a joint analysis between the power system and the future phasing in of CHP systems. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 153(3): 18–30, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20162     

Effects of Smart Charging of Multiple Electric Vehicles in Reducing Power Generation Fuel Cost

The high penetration of variable sources of renewable power generation will lead to operational difficulties in supply/demand balancing in the entire power system. The mass deployment of electric vehicles (EVs) and plug‐in hybrid vehicles (PHEVs) will also cause significant changes in electricity demand. Therefore, controlling and managing the charging time of EVs/PHEVs are effective approaches that are imperative for improving balancing in power system operation. We assumed travel patterns for EVs in a model of the future Tokyo power system and analyzed the power system loads, including the charging load of the EVs, under several charging control scenarios. We verified that charging time controls are substantially effective for reducing the fuel costs in the power system. Further, we found that load leveling under a multicar charging management scenario gave the best results in terms of the fuel costs in all cases.     

Development of an analytical model for generation expansion planning as a tool to provide guidelines for preventing instability in the long‐term electricity market

This paper considers the problem of deciding multiperiod investments for generation expansion planning (GEP) in restructured power systems. This problem has presented a challenge for both market managers and suppliers regarding the stability in the electricity market and minimum income for suppliers over the planning period. In this paper, an analytical model for studying the GEP problem from the viewpoint of a central management entity is presented. The aim of this method is to establish a dynamic balance between energy supply and demand by adjustment of GEP over the horizon of planning so that not only the expected profit is provided for all new generating plants but the long‐term stability in the electricity market is also improved. This analytical model can be utilized by regulatory bodies to obtain some guidelines and thereby to set their policies for improving GEP and preventing instability in the long‐term electricity market. To do so, in this study, the uncertainties of demand and supply have been modeled through two stochastic processes. Furthermore, the market price dynamics and their mutual effects on the GEP's results have been considered. Finally, this nonlinear dynamic optimization problem is solved using a modified genetic algorithm (GA). The efficiency and ability of the proposed method are examined on a test power system. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

减碳中多阶段的煤电机组退役与新能源、储能规划协同

规划现役煤电机组的有序退役是电力系统低碳化转型中的关键问题:煤电机组退役会造成发电量缺额和系统灵活性不足的问题,尤其是在新能源占比逐渐增大的条件下,而储能是平衡电力供需、提升供电灵活性的有效技术途径.故应将电力系统规划与未来较长时间内煤电机组逐步退役一同考虑.为此,采用多阶段模型,在电力系统减碳背景下将煤电机组退役协同...     

促进可再生能源电力接纳的技术与实践

我国已成为可再生能源发电装机规模与发电量最大的国家,可再生能源电力接纳问题日益突出,寻求该问题的解决方案将是"十三五"期间的重大任务。为此,该文从电力系统整体出发,分别从电网侧、发电侧及用户侧,梳理了促进可再生能源电力接纳的技术现状,总结了其技术特征与国内外实践经验,为我国"十三五"期间可再生能源接纳格局的改善提供借鉴。在电网侧,特高压输电技术、柔性直流输电技术、电网智能化技术将为我国可再生能源在更大范围的接纳提供坚强纽带,实现发电侧与用户侧间更为灵活、紧密的联系;在发电侧,常规机组的灵活调节技术、可再生能源的精细预测及主动控制技术、大规模储能技术将推动我国各类电源运行方式的深度转变;在用户侧,可再生能源电力供热、需求侧响应与虚拟电厂等技术将为终端用户主动、柔性地调节自身负荷、更多地使用可再生能源电力提供解决方案。依托特高压输电技术、融入大市场,实现可再生能源最大范围的优化配置,将是适合我国国情的重要选择。     

Analysis of long‐term profitability and DSM needs of utilities in a partially liberalized retail market by a generation system expansion model

Retail competition in the electric power market was introduced in Japan in March 2000. Although the liberalization is limited to a part of the retail power market having about 30% of the total electricity demand, the liberalized customer segment is now subject to competition among the utilities and new entrants. This paper examines the profitability of competitive pricing for eligible segmented customers through a scenario‐based model analysis focusing on the demand characteristics of segmented customers. The model includes the utility's investment in power generation for segmented customers, considering long‐term rather than short‐term profitability. Load leveling is not always achieved under profit‐maximizing behavior of the utility because the profitability of competitive pricing depends on load patterns of bypassed customers and price differentials among power suppliers. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 144(4): 43–52, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10111     

新电改背景下产业园区供电系统容量优化配置方法

产业园区作为新一轮电力体制改革的重要试点,利用分布式新能源发电来替代传统的集中式供电模式是其供电系统发展的重要趋势之一。开展了产业园区供电系统规划中分布式电源/储能系统优化配置问题的研究,重点研究了多能互补、源—储—荷协调互动和基于日前分时电价的需求侧响应对于容量优化配置方案的影响。为了表征多能互补特性,提出了分布式电源供电电量不足比和分布式电源供电不足小时数比两个指标。在需求侧响应建模时,针对利用电力需求弹性矩阵建模存在着电量转移不平衡及需求侧过度响应等问题,提出了改进的需求侧响应模型。在此基础上,建立了以总费用最小为优化目标的产业园区供电系统分布式电源/储能系统优化配置模型,并利用遗传算法与模式搜索算法相结合的组合型智能算法对优化配置模型进行求解,最后利用典型算例对提出的优化配置方法进行了分析验证。     

华东电网供需形势分析

阐述了华东电网在2008～2009年的供需情况,介绍了华东电网分地区、产业和行业划分的社会用电量下降及发电设备利用小时数下降等情况.介绍2009年夏季电力电量平衡情况.提出华东电网的应对举措.     

实施需求侧管理对提高发电系统可靠性的影响探究

实施需求侧管理可以提高能源利用率,减少最大负荷需求量,相当于间接增加了系统的发电容量,因此能够提高发电系统的可靠性。简要介绍了发电系统可靠性指标,建立发电系统可靠性分析模型,包括发电容量模型和负荷模型,并分析了非时序蒙特卡洛法在发电系统可靠性评估中的应用。采用模拟法定量,以IEEE可靠性测试系统RTS(Reliability Test System)为例定量分析需求侧管理对发电系统可靠性的影响,分析结果表明实施需求侧管理能够提高能源利用率和发电系统的可靠性,使系统更加安全、经济、可靠地对用户供电。     

需求响应参与电力平衡的成本效益评估方法

电力供需平衡是电力规划考虑的关键问题之一。“十四五”期间,中国能源消费仍将刚性增长,能源保供压力持续存在。取暖降温、电动汽车等用电负荷的增加导致电网尖峰负荷更加突出,给电力平衡带来新的挑战。需求响应参与电力平衡是解决电力平衡问题的一种新思路,能够提高电力规划投资效益。通过介绍需求响应参与电力平衡的基本方法,提出了需求响应参与电力平衡的成本效益评估方法,结合案例验证了方法的可行性和有效性。结果表明：需求响应参与电力平衡的经济性与需求响应补贴标准和需求响应比例有关,经济性随补贴标准提高而下降,随需求响应比例的增加先增加后下降,降为零时的需求响应比例为参与电力平衡的最佳比例。     

能源高质量发展下中国电力供需格局演变趋势

为应对气候变化,世界各国都在加快能源转型,习近平总书记提出了“四个革命、一个合作”能源安全新战略和“碳达峰、碳中和”愿景,要求全力推动能源高质量发展,这将对中国电力供需格局产生深远影响。首先,提炼能源高质量发展的内涵、特征;其次,从消费侧、供给侧、技术、体制等角度研判能源高质量发展下电力行业的转型发展方向;最后,通过构建多区域“能源-经济-电力”分析预测模型体系,从电力需求、电力供应、跨区电力流、电力系统形态、电力市场交易等方面研究中国中长期电力供需格局的演变特征。     

Application of unified voltage analysis for high‐ and low‐voltage distribution systems by power flow calculation using indication method between nodes

It has been noted that the voltage of connection points rises according to the reverse power flow when grid‐connected photovoltaic systems are concentrated in distribution systems in residential areas. When this happens, the photovoltaic system may control the power generation output to maintain a suitable voltage for the connection point. Designing a demand area power system aiming at free access to a distributed power supply for energy‐effective practical use requires a precise understanding of this problem. When analyzing photovoltaic systems mainly connected to low‐voltage systems, we looked for a method of analysis in which the high‐voltage systems and the low‐voltage single‐phase three‐wire systems are unified. This report concerns use of the indication method between nodes using power flow calculation, for the purpose of developing a technique of analyzing unified high‐voltage systems and low‐voltage single‐phase three‐wire systems. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(3): 49–62, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10255     

士兵系统电源保障技术发展进程

士兵系统在未来战争中具有重要作用,保障其信息化装备持续供电问题日益受到各国重视.对世界主要国家士兵系统电源保障技术进行了分析,总结了各国在储能电池、供电系统模式和发电技术等方面的研究和应用现状,进而从作战样式、用电需求、电池技术、系统架构等方面,分析了士兵系统电源保障面临的诸多挑战.从实战运用角度,提出未来士兵系统电源...