Complementarity Maps of Wind and Solar Energy Resources for Rio Grande do Sul, Brazil

If two or more renewable energy sources are available in the same region, their complementary can be advantageous in a hybrid power system. Three indices are defined in this work for assessing the complementarity of solar and wind resources for energy production. Based on existing data of solar radiation and wind speed, these complementarity indices were calculated and represented in the form of maps for the state of Rio Grande do Sul, in southern Brazil. The results found suggest that there are some areas of the state where the use of hybrid wind-solar power systems could be more effective than single photovoltaic or wind systems.

Feasibility Analysis of Constructing Solar Power Plant by Combining Large Scale Wind Farm

Hybrid utilization of renewable energy is one of effective method which can solve the problem that unstable of renewable energy so as not to substitute traditional fossil energy. As the typical renewable energy, solar energy and wind energy are in the van of renewable energy utilization. With the large scale utilization of solar and wind energy in the world, constructing large scale solar power plant in the large scale wind farm can make the most of ground resource combining the wind energy with solar energy. Feasibility of constructing large scale solar power plant in the large scale wind farm was analyzed in this paper, and come to a conclusion that constructing large scale solar power plant in the large scale wind farm can not also achieved the goal of mutual support of resource advantages and economizing money but also improved significantly the seasonal mismatch by combining solar with wind.

Design of a Hybrid Wind-Solar Energy System for an Agro-industrial Residential Area in Bota-Limbe, Cameroon

This paper proposes the most feasible technical and environmentally friendly hybrid power system configuration;a stand-alone hybrid wind-solar energy system with battery storage for a residential area of an Agro-industrial Company, Cameroon Development Cooperation (CDC), with headquarters in Bota-Limbe, south west region, Cameroon. The power network of the CDC Bota-Limbe Camp amongst other camps, which accommodates plantation workers, is plagued with challenges such as reliance on grid power which is unreliable, poor power quality which endangers home appliances and a spider webbed transmission system that poses as a threat to the lives of plantation workers. This paper addresses those concerns by designing a modular hybrid solar-wind renewable energy system for the camp. Limbe is a coastal area with proven existence of wind and solar resources. It is expected that the proposed system, if adopted and well implemented, will provide huge opportunities for the CDC in several other locations in Cameroon where there is adequate supply of renewable energy resources.

An Index Assessing the Energetic Complementarity in Time between More than Two Energy Resources

Energy complementarity can be a tool for managers to prioritize investments in new power generation ventures. An index for complementarity assessment should allow comparison of complementarities at different sites. This article proposes a new method for the calculation of complementarity index, allowing the comparison two energy resources and also allowing the comparison of more than two energy resources. In addition, the proposed index still allows the use of hourly or daily series and not only maximum or minimum values. Finally, this article also presents a map for the state of Rio Grande do Sul, the southernmost state of Brazil, indicating the energetic complementarity in time between hydropower, wind energy and PV solar energy.

Hybrid Power System Options for Off-Grid Rural Electrification in Northern Kenya

For domestic consumers in the rural areas of northern Kenya, as in other developing countries, the typical source of electrical supply is diesel generators. However, diesel generators are associated with both CO2 emissions, which adversely affect the environment and increase diesel fuel prices, which inflate the prices of consumer goods. The Kenya government has taken steps towards addressing this issue by proposing The Hybrid Mini-Grid Project, which involves the installation of 3 MW of wind and solar energy systems in facilities with existing diesel generators. However, this project has not yet been implemented. As a contribution to this effort, this study proposes, simulates and analyzes five different configurations of hybrid energy systems incorporating wind energy, solar energy and battery storage to replace the stand-alone diesel power systems servicing six remote villages in northern Kenya. If implemented, the systems proposed here would reduce Kenya’s dependency on diesel fuel, leading to reductions in its carbon footprint. This analysis confirms the feasibility of these hybrid systems with many configurations being profitable. A Multi-Attribute Trade-Off Analysis is employed to determine the best hybrid system configuration option that would reduce diesel fuel consumption and jointly minimize CO2 emissions and net present cost. This analysis determined that a wind-diesel-battery configuration consisting of two 500 kW turbines, 1200 kW diesel capacity and 95,040 Ah battery capacity is the best option to replace a 3200 kW stand-alone diesel system providing electricity to a village with a peak demand of 839 kW. It has the potential to reduce diesel fuel consumption and CO2 emissions by up to 98.8%.

Hybrid PV/Wind/Diesel Based Distributed Generation for an Off-Grid Rural Village in Afghanistan

Afghanistan has a tremendous resource potential of renewable energy especially solar and the wind. Therefore, utilization of these resources has a special rule for the remote areas where access to the electrical grid or secure power supply is a dream for most of the people. This paper presents a feasibility and usefulness of hybrid power generation based on PV/wind/diesel generator for an off-grid rural village that feeds the load at a rate of average 7.9 kWh/day with 1.32 kW peak load. GsT （geospatial toolkit） is used to obtain the solar and wind data of the site. Windographer software is used to analyze the wind resource data of the site. HOMER Pro software package is used to select the suitable and reliable hybrid generation system and calculate the optimal capacities and costs of the components. Through the study, it is found that this state of the art adaptation could provide vast opportunities for off-grid rural communities such as in Afghanistan where enough high penetration of renewable energy is available.

基于Hybrid2仿真的风光柴蓄复合发电系统设计与分析

由于传统能源的日益枯竭,风光互补发电已成为重要的研究方向。依据西藏地区气象数据和连队驻地用电情况,设计了风光柴蓄复合发电系统结构图,并利用Hybrid2软件对系统设计方案进行建模和仿真分析。根据仿真结果和经济性等因素,最终得到最优条件下光伏与风机系统设计数据。

Hybrid energy module for remote environmental observations, experiments, and communications

Increased concerns about climate change have led to a significant expansion of monitoring, observational, and experimental sites in remote areas of the world. Meanwhile, advances in technology and availability of low-power equipment have allowed increasingly sophisticated measurements with a wide variety of instruments. However, the deployment and use of these technologies in remote locations is often restricted not only by harsh environmental conditions, but also by the availability of electrical power and communication options. In some cases, research stations and military installations can provide power for scientific equipment, data acquisition, storage, and transmission. Clustering of research sites near existing infrastructure has had the unintended consequence of limiting a spatial understanding of large geographic regions. Fortunately, the modern market offers many power and communication solutions, but most of them are oriented toward large industrial applications. Use of those solutions to power a research site is limited because of their cost and need for significant modification for the specific research purposes. Each study has its own unique power requirements and needs for proper instrumentation. A power and communication solution for a vast majority of implementations with or without modification would be of considerable benefit. This article describes design of a universal, scalable hybrid energy module for the Next-Generation Ecosystem Experiments Arctic project(https://ngee-arctic.ornl.gov/). Two modules were built, and the authors describe their implementation and findings over a 2-year period at a remote field site on the Seward Peninsula in western Alaska, USA.

离网型风光发电联合制氢系统的协调运行策略与容量配置优化

离网型风光发电制氢是降低风光发电对电网冲击、促进可再生能源消纳的重要手段,然而风光资源的波动性也对制氢系统高效稳定运行带来了负面影响。为提高离网型风光制氢系统运行稳定性,结合风力/光伏发电、碱性电解槽(alkaline electrolyzer,AE)和储能设备,提出电解槽模式分配与储能日前规划的协调制氢策略,并在计及单位制氢成本与弃风弃光率的基础上,采用改进的非支配排序遗传算法(non-dominated sorting genetic algorithm II,NSGA-II)进行容量配置优化。结合案例分析表明,与单一电解槽分配策略相比,协同策略的单位制氢成本和弃风弃光率分别降低了11.9%和55.6%。同时该策略有效平抑了电解槽的频繁波动,启停次数降低了44.3%,实现了风光制氢系统的高效运行。研究成果将为开发高效可再生制氢系统提供有益参考。

风光电源故障暂态解析及实用化短路电流峰值计算

研究风光电源的故障暂态过程及短路电流峰值能为设备选型及保护整定提供重要依据。然而,现有的风光电源暂态短路电流计算模型过于依赖参数,计算模型难以满足工程应用需求。因此,该文首先分别对光伏电源、永磁同步风机及双馈感应风机进行故障暂态解析,继而构建形式简洁实用的短路电流峰值表达式。对于光伏电源及永磁同步风机,在恒功率控制阶段建立了基于故障期间电源出力变化的暂态短路电流计算模型;在限幅控制阶段通过分析阻尼比系数,得到短路电流峰值的实用化表达式。对于双馈感应风机,通过分析其故障后定转子磁链的耦合关系,得到Crowbar电阻投入阶段短路电流的简化条件,进而求解出短路电流峰值表达式。最后通过录波数据与仿真数据验证了理论的可行性和正确性。

双向无线电能传输系统在V2G中的控制策略研究

为弥补电动汽车与电网间能量单向流动不足,提高电动汽车充放电的灵活性与新能源发电的就地消纳能力,提出1种含电动汽车双向无线电能传输的直流微网拓扑结构,研究了将车载电池作为移动储能设备的控制方法。以风光互补发电系统与混合储能为基础,针对双向无线电能传输系统提出基于功率的控制方法,可保证电动汽车作为负荷吸收电能,又可当作储能单位发出电能。为保证系统稳定运行,进一步设计了微网上层中心控制器。Simulink仿真结果表明:电动汽车与电网的能量交互提高了电网运行稳定性,双向无线电能传输可提升电动汽车充放电效果,在一定程度上促进了新能源发电的就地消纳,验证了所提拓扑的有效性与控制策略的优越性。

基于混合柔直的水风光一体化新型电力系统简化建模方法

依托国内新建含混合柔性直流外送的水风光多能互补一体化新型区域电力系统工程实际,针对该系统三个核心组成场站,即水电机组侧、风光汇集系统侧和混合柔性直流的区域化模型分别进行简化建模,而后通过实验对比验证响应模型和本文提出的等效模型。结果表明,本文提出的新能源区域电力系统等效模型可以在发生故障时对系统动态过程在机电仿真尺度进行高精度等效。由于其具有易拓展性和广泛适用性,可作为研究极大规模高比例新能源电力系统的实验范式。

风光互补发电系统中储能系统控制策略研究

作为一种高效的非支配排序遗传算法,NSGA-II算法在多个优化问题的求解中发挥着重要作用。特别是在风光互补发电系统的储能控制优化方面,NSGA-II算法被广泛应用于寻找最优的储能控制策略,以实现系统经济效益的最大化和碳排放量的最小化,为可持续发展贡献力量。对此,基于NSGA-II算法构建了储能模型,分析了风光互补发电系统的能源转换,并结合负荷缺电率、系统成本函数设计了基于NSGA-II算法的风光互补发电系统容量优化方法。同时,应用Matlab软件开展对比实验,结果显示本研究提出的方法能够有效管理能量流动,提高能源利用效率,从而增强了控制策略的有效性与实用性。

离网型户用风光互补发电系统的匹配

以内蒙古苏尼特右旗安装的一套离网型户用风光互补系统为例对系统的风电机组、光伏发电机组及系统的每月日均发电量进行了测试分析。结果表明,系统在风电机组发电量最低的7、8、9月仍能够保证用户需求,向用户稳定供电,不需再增加光伏组件。系统匹配性能良好,设计合理。

基于风光互补的微网系统建模与仿真

在传统风光互补发电系统的基础上,建立了基于直流母线的单相微网系统模型,利用Matlab分别搭建了风力发电机、光伏阵列和蓄电池的模型,系统主电路采用Z拓扑结构延长了孤岛运行时间。微网控制策略根据运行模式分为两种:孤岛运行时,系统采用主从控制模式,其中蓄电池作为主控单元,提供电压参考;并网时尽可能地将新能源并入电网,分别进行最大功率点跟踪控制。利用该模型及控制策略对微网两种模式切换时的过渡状态以及功率流向进行了仿真研究,结果验证了该模型的可行性和有效性,为建立微网实验平台和示范工程奠定了基础。

含多种分布式电源的微电网经济调度研究

微电网的优化调度是一个新的具有重要社会和经济效益的复杂问题。基于实际风光资源、负荷和微电网运行成本数据,将用户效益、环境保护以及社会效益量化为运行及维护成本、未满足负荷、污染气体排放量、容量短缺等指标,采用模糊评价函数将多目标转化为单目标,提出了针对该微网的短期经济优化调度模型。选取一年中的典型情况为算例进行经济运行分析,并采用小生境遗传算法进行求解,得出了在各典型情况下各微电源的最优出力和最佳电能交易计划,验证了所提调度策略的正确性与有效性。

风光蓄互补发电系统容量的改进优化配置方法

风光互补发电系统利用风能与太阳能的互补特性,相比于单独的光伏发电或风力发电,其输出功率波动小。合理配置风电/光伏/储能的容量,既可提高系统供电可靠性,又可降低系统成本。针对风光蓄互补发电系统,提出一种改进的容量优化配置方法,考虑独立和并网两种模式,对风力发电、光伏发电和蓄电池的容量进行最优配置。该方法充分利用风光互补特性,在系统独立运行时,只需较小的蓄电池容量即可保证高供电可靠性,并可减少蓄电池的充放电次数和放电深度;在系统并网运行时,进一步提出采用分时段优化策略来配置所需蓄电池的容量,保证负荷供电需求和入网功率的波动特性满足要求。算例验证了所提改进优化方法的合理性和优越性。

风/光复合发电系统变结构仿真建模研究

提出了风/光复合发电系统(WSHPS)变结构仿真的一般数学模型,包括系统结构定义、系统各部件数学模型。在此基础上,在C++ Builder 环境下开发了相应的仿真软件。运用该软件,对一实例进行了计算。结果表明:利用该文提出的变结构仿真数学模型及相应仿真软件,用户可以重构多种结构的风/光复合发电系统并进行计算机仿真计算,从而能够预测系统的性能,如,太阳电池阵列功率、风力发电机功率、与负载功率之间的匹配性,控制策略的合理性,以及系统运行的效率等等。

适用于海上风场并网的混合多端直流输电技术研究

针对海上风电并网的需求,提出了采用VSC换流器连接海上风场和弱受端交流系统,LCC换流器连接较强交流系统的混合多端直流输电系统拓扑结构,并对一个混合5端直流输电系统进行了详细研究。分析了5个换流器的电压电流控制特性,设计了直流系统控制策略,研究了系统在风速波动、逆变侧VSC和LCC分别出现三相短路故障以及直流线路故障时系统的动态响应特性。仿真结果表明所提出的混合多端直流输电系统具有较好的运行特性,可以适应海上风电并网的需求。

风电场交直流混合输电并网中VSC-HVDC的控制

为提高风电场交直流混合输电并网的系统性能,提出一种更加灵活的电压源换流器高压直流(voltage source converter based high voltage direct current,VSC-HVDC)控制策略。对于风电场侧电压源换流器,设计了一种新的交流电压–功角控制方法。对于交直流混合输电模式,该方法通过调节风电场交流母线电压与电压源换流器输出电压间的功角来实现定有功功率控制。对于纯柔性直流输电模式,风电场交流母线电压自动被调节为具有恒幅恒频的交流电压,实现了对波动风电的同步输送。该方法中输电模式的变化无需切换控制;另外,通过附加电流高通滤波器增强了对系统谐振的阻尼作用。对电网侧电压源换流器,采用一种新的直接电流矢量控制,使直流电压稳定在参考值上。运用PSCAD/EMTDC仿真软件对分别接入笼型感应发电机(squirrel cage induction generator,SCIG)风电场和双馈感应发电机(doubly fed induction generator,DFIG)风电场的交直流混合输电系统建模仿真。一系列运行条件下的仿真结果验证了控制方法的有效性与可行性。