计及风光不确定性的新能源虚拟电厂多时间尺度优化调度

针对中国西北地区新能源消纳问题,该文聚合风力发电、光伏发电、光热电站、电储能装置组成虚拟电厂（VPP）,提出一种基于鲁棒随机优化理论的新能源虚拟电厂多时间尺度优化调度策略。首先对风力发电、光伏发电、光热电站与电储能装置进行数学描述,在此基础上建立VPP多时间尺度优化调度模型。在日前调度层中,以VPP运行效益最大为目标,依据风光日前预测出力建立日前优化调度模型;在时前调度层中,以VPP运行成本最小为目标,根据风光时前预测出力建立时前调度修正模型。同时,为了衡量风电、光伏发电出力不确定性对系统的运行影响,建立VPP随机优化调度模型。仿真结果验证该模型可提高运行效益与新能源消纳能力。     

考虑需求响应的风光燃储集成虚拟电厂双层随机调度优化模型

为促进以风光为代表的分布式能源发电并网,文章集成了风电、光伏发电、燃气轮机、储能系统和激励型需求响应为虚拟电厂,引入两阶段优化理论克服风光不确定性,建立VPP双层随机调度优化模型。首先,介绍了VPP的基本结构,建立了电源出力模型和需求响应模型。然后,建立了虚拟电厂双层调度优化模型:在上层模型中,根据风电和光伏发电日前预测结果,制定日前调度计划;在下层模型中,根据WPP和PV的实际输出,修正日前调度计划,形成最终VPP调度方案。最后算例分析表明:所提模型能够衔接日前调度和时前调度,降低系统缺电惩罚成本,提升VPP运营收益。储能系统能够利用自身充放电特性配合VPP内部风电和光伏发电出力,有利于平缓系统净负荷曲线。PBDR能够引导用户侧配合VPP发电调度,削峰作用弱于IBDR,而填谷作用强于IBDR。同时引入ESSs和DR后,VPP运营收益达到最高,表明ESSs和DR具有协同优化效应。     

计及风火系统聚合特性的虚拟电厂经济调度研究

提出一个VPP(虚拟发电厂)聚合出力特性的含新能源电网的两阶段经济调度模型。第一阶段基于包含若干风场与火电机组的VPP聚合出力特性决策VPP的总出力;第二阶段将总出力在VPP内部各发电单元之间进行分配。上述两个阶段都采用线性规划方法求解。基于IEEE—6母线电网的数值算例的计算结果表明,与传统经济调度方法相比,本研究提出的模型能降低风电弃风量近50%。     

含电动汽车的虚拟电厂经济性优化调度

将不可控新能源、电动汽车与可控电源构建成虚拟电厂(VPP),通过虚拟电厂优化调度各组成部分出力,使虚拟电厂对外表现为有一定可控性的、稳定的发电单元,减小新能源与电动汽车单独入网运行时对电网造成的冲击。为实现上述功能,该文构建含电动汽车的虚拟电厂经济优化调度模型,设计含电动汽车的虚拟电厂经济运行策略,在Matlab R2010a平台上采用粒子群算法优化各组成部分出力,并分析电动汽车渗透率和可控电源计划出力系数对虚拟电厂经济性和各机组出力的影响。仿真结果表明,通过电动汽车与可控电源联合出力能够弥补新能源出力偏差,降低可控机组旋转备用,提高虚拟电厂供电可靠性。     

基于纳什谈判的多能VPP群协同优化运行策略北大核心CSCD

随着新能源规模的不断扩大以及各种资本进入电力市场,未来电网运行将呈现出多虚拟电厂(virtual power plant,VPP)相互合作并竞争的博弈格局。为解决电网优化运行和市场主体利益分配问题,本工作提出了基于纳什谈判的多能VPP间协同优化运行模型。首先,针对包含燃气轮机、热泵、多种储能装置、电热冷负荷等的多能VPP,构建基于纳什谈判理论的多能VPP群优化运行模型;其次,为解决复杂非凸非线性优化的求解问题,依据均值不等式将模型转化为多能VPP效益最大化和多能VPP间电能支付值两个子问题;再次,考虑到各VPP间信息隐私安全,采用交替方向乘子法(alternating direction method of multipliers,ADMM)对上述两个子问题进行分布式求解。本工作选取了三个多能VPP进行算例分析,结果表明本工作提出的优化方法可以实现在兼顾公平性的前提下提升各VPP的收益和整体收益。     

一种考虑新能源出力相关性及不确定性的分布式发电规划策略

分布式可再生能源的大规模应用及并网给传统电网的规划及运行均带来了挑战及冲击。该文提出一种考虑新能源出力相关性及不确定性的分布式发电规划策略。该方法首先基于Cholesky分解同时获得满足风电出力分布及风电场出力相关性的新能源出力抽样方法。然后,考虑新能源出力的不确定性,提出一种基于新能源多场景出力的概率规划模型。随后,基于该模型规模庞大、约束非线性特点,提出一种基于节点有功变化的部分线损计算策略。最后,在IEEE 33节点测试系统上进行了测试,证明了该方法的有效性。     

风光联合微电网系统电源优化配置

考虑微电网中新能源发电出力相关性及不同负荷功率间的相关性,基于Copula理论分别建立新能源发电联合出力、不同负荷总功率概率分布模型,利用历史模拟法得到微电网运行规划中的风险价值,实现对微电网的风险评估。以考虑投资成本、低碳费用、并网运行电能交易等综合经济成本为目标,构建微电网电源优化配置模型。采用改进入侵杂草优化算法求解最优方案。结果表明改进入侵杂草优化算法收敛速度快,寻优能力强。最后,采用算例分析微电网各单元相关性,阐明结合相关性建立的优化配置模型的优越性,验证模型和算法有效性。     

基于微能源网联供系统的光伏电源出力等效平滑策略研究

提出利用微能源网内部相对容量较大的微型燃气轮机调峰,通过优化调度微型燃气轮机的电、热出力,实现接入微能源网的光伏出力的等效平滑,增加光伏消纳。调节策略以微能源网系统日运行费用最小为目标函数,建立该微能源网经济调度模型,使用混合整数非线性规划算法求解。算例计算表明:1)基于微能源网内部微型燃气轮机10%装机容量/min的调峰速度,可获得76%装机容量的电力调峰深度,26.7%装机容量的热力调峰深度,实现光伏电源波动性出力的等效平滑。2)在微能源网日运行周期内,光伏电源出力离散系数比等效平滑前降低65.18%,光伏电源出力得到等效平滑,使得光伏电源出力消纳平均提高4.86%;3)与以热定电和以电定热2种调度策略相比较,使用本文提出的调度策略可使系统日运行费用分别降低7.323%和10.472%,表明所提模型和调度方案的经济可行性。     

含不同集群电动汽车的微电网优化调度

文章考虑微电网中的可再生能源出力,针对不接受微电网直接调度的电动汽车集群,提出一种基于等效负荷的实时电价策略进行电动汽车有序充、放电引导。该策略与微电网直接调度策略相结合,对不同集群电动汽车进行充、放电管理,并综合考虑环境效益、车主收益与微网运行状态,建立了以微电网综合运行成本最低、负荷波动最小为目标的优化模型,并用灰狼优化算法求解。优化结果表明,所提出的策略能够合理调度各可控发电单元,引导电动汽车有序充、放电,减少微电网运行成本,降低等效负荷的波动。     

风电与燃气轮机互补发电系统发电成本分析

在采用风电场与小型燃气轮机组成的互补系统发电特性参数的基础上,详细分析了互补系统发电成本的构成和各自的计算方法。采用新疆达坂城风电场的风速数据,基于互补系统的发电特性参数和风电场与燃气轮机电站的发电成本构成,应用改进过的等额支付折算法,在当前的技术条件和价格下,计算了风电场子系统和燃气轮机电站子系统各自的折旧成本、燃料成本和运行维护成本,得到了整滚发电系统发电成本的计算方法,为在新疆地区实现这种互补发电系统提供经济分析基础。     

考虑低谷调峰限制和环境成本的发电容量规划

提出一种考虑低谷调峰限制的含可再生能源电力系统发电容量规划模型,该模型能确保通过运行调度最优发电容量组合满足规划年中每一天的低谷调峰限制,然后结合筛选曲线法和拉格朗日松弛法进行求解。而且,为了研究环境成本对发电容量规划和系统调峰性能的影响,在发电成本中增加CO₂排放成本。最后,算例分析验证所提方法的合理性和有效性,结果表明了在高渗透率可再生能源电力系统发电容量规划中综合考虑低谷调峰限制和环境成本的必要性。     

Comparison of options for distributed generation in India

There is renewed interest in distributed generation (DG). This paper reviews the different technological options available for DG, their current status and evaluates them based on the cost of generation and future potential in India. The non-renewable options considered are internal combustion engines fuelled by diesel, natural gas and microturbines and fuel cells fired by natural gas. The renewable technologies considered are wind, solar photovoltaic, biomass gasification and bagasse cogeneration. The cost of generation is dependent on the load factor and the discount rate. Gas engines and Bagasse based cogeneration are found to be the most cost effective DG options while wind and biomass gasifier fired engines are viable under certain conditions. PEM Fuel cells and micro turbines based on natural gas need a few demonstrations projects and cost reductions before becoming viable. A strategy involving pilot projects, tracking of costs and dissemination of information is likely to result in DG meeting 10% of India's power needs by 2012.     

小水电与风光并网的经济效益与环境效益研究

建立了有蓄水库的小水电站与风光混合发电系统的结构模型。研究峰谷电价下,小水电与风光并网所带来的能量转化经济效益和开发清洁能源电力所带来的节能减排环境效益。仿真算例验证了所建模型的有效性。结果表明,有蓄水库的小水电站可以将风光混合发电系统低谷时段所发的廉价电能转化为高峰时段的稀缺电能,带来能量转化的经济效益,同时可以平抑输出功率的波动性,提高电网供电的稳定性与可靠性。经过对污染物减排量的计算,证明了小水电与新能源并网能够有效地节约煤炭等非可再生能源,对保护环境很有意义。     

Hydropower Systems and Hydropower Potential in the European Union Countries

Hydropower is today the most important kind of renewable and sustainable energy. Resources of hydropower are widely spread around the world. Hydro energy is the most reliable and cost effective renewable energy source. It is obvious that among all the renewable energies, hydropower occupies the place in the world, and it will keep this place for many years to come. Hydroelectric energy is responsible worldwide for some 2600 TWh of electricity output per year, which means about 20% of the world's entire electricity demand, making it one of the most reliable and cost effective renewable energy sources. In 2001, the largest hydropower generating countries were Canada (333.0 TWh), the United States (201.2 TWh) and Norway (120.4 TWh). Hydroelectric power consumption in the EU grew by nearly 27% between 1991 and 2001. In 2001, hydro accounted for approximately 5% of total EU power consumption. France is the EU's largest producer of hydroelectricity. In 2001, generation capacity of hydropower was about 25,000 MW in France.     

微网中光伏发电系统的储能控制研究

利用可再生能源（如太阳能和风能）的分布式发电,其输出是典型的不稳定,这些不稳定的输出对现有的电力系统产生负面影响。为了减少负面影响,需要控制在微网中的各个分布式电源的输出。设计了一种基于蓄电池储能的并网光伏发电系统结构,结合功率流动的控制策略介绍了各部分的运行原理,对系统能流模型进行了详细分析,根据电池的特性设计了充放电的控制策略。在PSCAD平台下对设计的模型进行仿真,通过在不同能流模型下控制策略仿真分析,验证所提出储能方案的正确合理性,对功率平衡起到很好的调节作用。     

基于水库大坝的水能与太阳能融合型并网发电系统研究与应用

针对中国大中型面南的水库电站大坝,向光性比较好,具备安装太阳能光伏发电系统的条件,并使得2种可再生能源融合并网发电模式具有一定的创新性.水库电站的发电系统是已建成的,增加太阳能光伏发电系统并建设融合型并网发电系统,不仅体现了投资成本低发电效益高等特点,同时具有节约国土资源、保护大坝和节能减排等社会效益.在设计和实践过程...     

State of the art of the virtual utility: the smart distributed generation network

The world of energy has lately experienced a revolution, and new rules are being defined. The climate change produced by the greenhouse gases, the inefficiency of the energy system or the lack of power supply infrastructure in most of the poor countries, the liberalization of the energy market and the development of new technologies in the field of distributed generation (DG) are the key factors of this revolution. It seems clear that the solution at the moment is the DG. The advantage of DG is the energy generation close to the demand point. It means that DG can lower costs, reduce emissions, or expand the energy options of the consumers. DG may add redundancy that increases grid security even while powering emergency lighting or other critical systems and reduces power losses in the electricity distribution. After the development of the different DG and high efficiency technologies, such as co‐generation and tri‐generation, the next step in the DG world is the interconnection of different small distributed generation facilities which act together in a DG network as a large power plant controlled by a centralized energy management system (EMS). The main aim of the EMS is to reach the targets of low emissions and high efficiency. The EMS gives priority to renewable energy sources instead of the use of fossil fuels. This new concept of energy infrastructure is referred to as virtual utility (VU). The VU can be defined as a new model of energy infrastructure which consists of integrating different kind of distributed generation utilities in an energy (electricity and heat) generation network controlled by a central energy management system (EMS). The electricity production in the network is subordinated to the heat necessity of every user. The thermal energy is consumed on site; the electricity is generated and distributed in the entire network. The network is composed of one centralized control with the EMS and different clusters of distributed generation utilities and heat storage tanks. Each of these clusters is controlled by a local management station (LMS). Every LMS has information about the requirements (heat, cold and electricity) of the users connected to its cluster and the state of the utilities and water level of the storage tanks in its cluster. The EMS receives the information from the LMSs and sets the electricity input or output of every cluster in the network. With the information ordered by the EMS, the LMS set the run or stand‐by of the utilities of its cluster. The benefits of the VU are the optimization of the utilization yield of the whole network, the high reliability of the electricity production, the complete control of the network for achieving the main aim of the EMS, the high velocity for assuming quick changes in the demand of the system and high integration of renewable energy sources, plus the advantages of the DG. This paper indicates the state of the art of the VU concept, analyses the projects that are being developed in this field and considers the future of the VU concept. Copyright © 2004 John Wiley & Sons, Ltd.     

基于水电站大坝的太阳能融合型并网发电系统研究与应用

针对双可再生能源融合发电模式的诸多技术难题,提出了一种在水电站大坝上建设太阳能电站并进行融合发电的创新模式,重点突破了水电与太阳能发电共享型控制技术、光伏逆变谐波抑制技术、无功补偿和共享型直流技术等技术难题。水电和太阳能发电共享型控制技术实现了水电现地控制单元、太阳能现地控制单元、共享型公用现地控制单元的分布式构架;实现了光伏对水电的逆变谐波抑制和无功补偿装置的研发;实现了太阳直流技术补偿水电站直流系统。应用实践表明,太阳能与水能融合发电模式可节约投资、增加无功补偿效益、减少国土资源的占用,是双可再生能源融合发电的创新性应用,具有很好的推广价值。     

我国清洁能源碳减排效益分析及发展顺序

发展低碳能源是应对全球气候变化、实现电力低碳化发展的有效途径,最终要以发电技术在具体工程项目中应用来实现,衡量各技术的经济可行性、评价可再生能源发电技术CO2的减排效益是关键。分析了当前我国主要5种低碳发电技术置换火电的碳减排成本及产生的碳减排效益,并对2020年低碳能源发电技术的碳减排潜力进行了测算。结果表明,水电发电成本及相应的碳减排成本最低,核电其次,光伏发电最高,应优先发展水电、大力开发核电,同时积极发展风电等其他低碳能源。     

Grid integrated renewable DG systems: A review of power quality challenges and state-of-the-art mitigation techniques

Increased energy demands due to rapid industrialization, environmental concerns with fossil fuel–based generation, diminishing fossil energy resources, transmission network congestion, and technical performance deterioration are the motivations behind the integration of small renewable distributed generation (DG) units and turning the existing power systems into a restructured one. Optimizing the technical benefits offered by DG placement is a well-known challenge for distribution network operators (DNOs) for both fossil and renewable energy resource–based DGs, but renewable DG systems have several power quality (PQ) challenges associated additionally. Power quality is a very significant characteristic of renewable DG systems because today's loads are more sensitive to PQ disturbances and penetration of renewable energy as well as nonlinear loads is proliferating in distribution power networks. So the need for innovative power quality improvement (PQI) techniques becomes inevitable due to ongoing reformation in traditional distribution networks by the integration of renewable energy. This article presents a comprehensive analysis of power quality challenges with grid integration of renewable DG systems and current research status of associated mitigation techniques. Firstly, this paper puts emphasis on theoretically illustrating all the crucial power quality challenges associated with grid integration of renewable energy, and secondly, a thorough survey, of all PQI techniques introduced till date, is elaborated along with highlighting the opportunities for future research. Furthermore, all the crucial power quality issues, the impact of high penetration of renewable energy and mitigation techniques on power quality, are demonstrated also by simulating a grid integrated PV-based DG system in MATLAB/Simulink. This article is believed to be very beneficial for academics as well as industry professionals to understand existing PQ challenges, PQI techniques, and future research directions for renewable energy technologies.