Hydro and Wind Power Integration: A Case Study of Dargai Station in Pakistan

Pakistan is facing acute energy crises since last few years. Due to shortage of fuel oil and its sky touching prices, it seems very uneconomical to generate electricity from fuel oil. In order to generate cheap electricity we have to rely on renewable energy resources. To address these challenges, wind power generation is among the popular options in the world which is now being considered in Pakistan as well. However unremitting change in wind speed from calm to stormy introduces real challenges. Storing wind energy in batteries during the periods of low demand seems an expensive option, especially when dealing with large scale power generation. Due to incessantly varying nature of wind speed, it is not feasible to rely only on wind power for cheap power production. Also, it is not thriftily possible to construct separate transmission line. However if we integrate wind power with hydro power, we can utilize the maximum possible transmission capacity. Existing hydro power station operating in that area or pumped storage scheme can be used. This paper is an attempt to analyze coordination of wind generation with hydro power in those areas of Pakistan where both wind and hydro power sources exist. In this paper, different issues have been analyzed taking case study of Dargai. This paper is first attempt in Pakistan about integration of wind and hydro power to draw some general conclusions and to point out some areas in which further research can be done.

Overview of Wind Power Integration in China

With the rapid development of wind power in China, the grid integration of wind energy systems has imposed lots of influences on the security and operation of power grids. This paper provides an overview of the characteristics of the wind power development in terms of distribution area, wind farm scale, integration voltage level and performance of wind turbines. The paper also presents an analysis of the problems and reasons emerging from the wind power integration in China and ends with putting forward some measures and suggestions about the wind power integration and operation for reference.

Analysis and Power Quality Improvement in Hybrid Distributed Generation System with Utilization of Unified Power Quality Conditioner

This paper presents a comprehensive study that includes the sizing and power flow by series and parallel inverters in a distributed generation system(DGs)that integrates the system of hybrid wind photovoltaic with a unified power quality conditioner(UPQC).In addition to supplying active power to the utility grid,the system of hybrid wind photovoltaic functions as a UPQC,compensating reactive power and suppressing the harmonic load currents.Additionally,the load is supplied with harmonic-free,balanced and regulated output voltages.Since PVWind-UPQC is established on a dual compensation scheme,the series inverter works like a sinusoidal current source,while the parallel inverter works like a sinusoidal voltage source.Consequently,a smooth alteration from interconnected operating modes to island operating modes and vice versa can be achieved without load voltage transients.Since PV-Wind-UPQC inverters handle the energy generated through the hybrid wind photovoltaic system and the energy demanded through the load,the converters should be sized cautiously.A detailed study of the flow of power via the PV-Wind-UPQC is imperative to gain a complete understanding of the system operation and the proper design of the converters.Thus,curves that allow the sizing of the power converters according to the power flow via the converters are presented and discussed.Simulation results are presented to assess both steady state and dynamic performances of the grid connected hybrid system of PV-Wind-UPQC.This investigation is verified by simulating and analyzing the results with Matlab/Simulink.

Application of Power Electronics Converters in Renewable Energy

Against the backdrop of global energy shortages and increasingly severe environmental pollution,renewable energy is gradually becoming a significant direction for future energy development.Power electronics converters,as the core technology for energy conversion and control,play a crucial role in enhancing the efficiency and stability of renewable energy systems.This paper explores the basic principles and functions of power electronics converters and their specific applications in photovoltaic power generation,wind power generation,and energy storage systems.Additionally,it analyzes the current innovations in high-efficiency energy conversion,multilevel conversion technology,and the application of new materials and devices.By studying these technologies,the aim is to promote the widespread application of power electronics converters in renewable energy systems and provide theoretical and technical support for achieving sustainable energy development.

Effect of photovoltaic panel electric field on the wind speed required for dust removal from the panels

Methods to remove dust deposits by high-speed airflow have significant potential applications,with optimal design of flow velocity being the core technology.In this paper,we discuss the wind speed required for particle removal from photovoltaic(PV)panels by compressed air by analyzing the force exerted on the dust deposited on inclined photovoltaic panels,which also included different electrification mechanisms of dust while it is in contact with the PV panel.The results show that the effect of the particle charging mechanism in the electric field generated by the PV panel is greatly smaller than the effect of the Van der Waals force and gravity,but the effect of the particle charged by the contact electrification mechanism in the electrostatic field is very pronounced.The wind speed required for dust removal from the PV panel increases linearly with the PV panel electric field,so we suggest that the nighttime,when the PV electric field is relatively small,would be more appropriate time for dust removal.The above results are of great scientific importance for accurately grasping the dust distribution law and for achieving scientific removal of dust on PV panels.

Performance Analysis of Grid Connected and Islanded Modes of AC/DC Microgrid for Residential Home Cluster

This paper presents performance analysis on hybrid AC/DC microgrid networks for residential home cluster. The design of the proposed microgrid includes comprehensive types of Distributed Generators (DGs) as hybrid power sources (wind, Photovoltaic (PV) solar cell, battery, fuel cell). Details about each DG dynamic modeling are presented and discussed. The customers in home cluster can be connected in both of the operating modes: islanded to the microgrid or connected to utility grid. Each DG has appended control system with its modeling that will be discussed to control DG performance. The wind turbine will be controlled by AC control system within three sub-control systems: 1) speed regulator and pitch control, 2) rotor side converter control, and 3) grid side converter control. The AC control structure is based on PLL, current regulator and voltage booster converter with using of photovoltaic Voltage Source Converter (VSC) and inverters to connect to the grid. The DC control system is mainly based on Maximum Power Point Tracking (MPPT) controller and boost converter connected to the PV array block and in order to control the system. The case study is used to analyze the performance of the proposed microgrid. The buses voltages, active power and reactive power responses are presented in both of grid-connected and islanded modes. In addition, the power factor, Total Harmonic Distortion (THD) and modulation index are calculated.

Mesoscale Wind Farm Placement via Linear Optimization Constrained by Power System and Techno-economics

The objective of this study is to develop a wind farm placement and investment methodology based on a linear optimization procedure.This problem has a major significance for the investment success for the projects of renewable energy such as wind power.In this study,a mesoscale approach is adopted whereby the wind farm location is investigated in comparison with a microscale approach where the location of each individual turbine is optimized.Specifical study focuses on the placement of a wind farm by economical optimization constrained by the power system,wind resources,and techno-economics.Linear optimization is introduced in this context at the power system which is constrained by wind farm planning.

Optimal Scheduling for Flexible Regional Integrated Energy Systemwith Soft Open Point

The Regional Integrated Energy System(RIES)has brought new modes of development,utilization,conversion,storage of energy.The introduction of Soft Open Point(SOP)and the application of Power to Gas(P2G)technology will greatly deepen the coupling of the electricity-gas integrated energy system,improve the flexibility and safety of the operation of the power system,and bring a deal of benefits to the power system.On this background,an optimal dispatch model of RIES combined cold,heat,gas and electricity with SOP is proposed.Firstly,RIES architecture with SOP and P2G is designed and its mathematical model also is built.Secondly,on the basis of considering the optimal scheduling of combined cold,heat,gas and electricity,the optimal scheduling model for RIES was established.After that,the original model is transformed into a mixed-integer second-order cone programming model by using linearization and second-order cone relaxation techniques,and the CPLEX solver is invoked to solve the optimization problem.Finally,the modified IEEE 33-bus systemis used to analyze the benefits of SOP,P2G technology and lithium bromide absorption chillers in reducing systemnetwork loss and cost,as well as improving the system’s ability to absorb wind and solar and operating safety.

国有大型油气企业新能源发电项目经济评价探讨

国有大型油气企业基于减排降碳和可持续健康发展考量,积极探索新能源发电业务,投资项目经济评价方法和参数,成为影响新能源发电业务投资决策和高质量发展的决定性因素。基于经济评价基本原理,根据新能源发电项目技术经济特征,构建新能源发电项目经济评价方法和参数体系。折现现金流法仍然是新能源发电项目经济评价的主要方法,内部收益率和平准化度电成本是衡量项目盈利能力的重要指标。不同类型新能源发电项目经济评价方法具有较高的一致性,但应在投资构成、成本费用估算、收入与税金估算等方面体现差异,重点在营业收入估算中体现项目真正价值。在规制性配置储能要求以及储能收益政策有待落实的情况下,新能源发电项目效益有待提高,建议现阶段适当降低投资回报要求,尤其是出于市场拓展和协同发展目的的战略性新能源发电项目。项目电价和有效利用小时数对新能源发电项目的影响至关重要,应视情况合理选取参数。风光气电融合项目应分业务估算成本。国有大型油气企业应积极开展宏观配套政策和商业模式创新研究,以支撑新能源发电业务的高质量发展。

黄河上游青海水风光蓄一体化发电系统研究

随着双碳目标加速落实与黄河流域生态保护和高质量发展规划实施,统筹推进水风光一体化基地建设并构建多能互补发电系统,能提升跨省跨区电网错峰支援和余缺互济能力。通过采用归纳梳理的方法对黄河上游青海省水风光资源和多能互补著绩进行了分析,结果表明:青海南部水电势能、北部太阳能和西部风能资源潜力较大,但各种新能源随开发规模的扩大其可开发潜力呈下降趋势。青海省规划的风光容量配比为0.6∶0.4,2025年情景下水电与风光配比为1∶1.2,2035年情景水平下为1∶1.25。此外,在电网系统中尽可能少接风电多接光伏且弃电率保证在5%以内对电网稳定运行和投资成本具有正反馈作用。

海上漂浮光伏发电技术及其融合发展展望

[目的]在“双碳”背景下,我国沿海省市逐步加大向海洋开发清洁能源的力度。海上风电场建设已经初具规模并已逐步实现平价上网,海上漂浮式光伏(Floating Photovoltaic,FPV)试点项目正在不断涌现。探索多种海洋资源的综合开发,在能源领域集约用海,打造海上综合能源系统,对于沿海省份高质量地实现碳中和具有重要意义。[方法]总结了目前国内外海上FPV技术发展及工程试点情况,分析了各种海上FPV技术的优势及挑战,预测了在中国近海发展FPV的市场规模,提出并探讨了海上FPV与海上其他基础设施的融合发展方式,并结合案例给出了融合建设场景及经济性分析。[结果]海上FPV技术目前总体处于试验和试点阶段,未来在国内外市场应用空间广阔,其主要技术难点是浮体在严苛海洋环境条件下的生存能力,现有试点工程单位造价相对较高,但与其他海洋设施结合发展潜力巨大。[结论]海上漂浮式光伏与海上风电等其他海上设施融合建设可以有效提高能源设施的利用效率,降低建设和运行的成本。海上风光互补还较好地解决了单一能源供应的稳定性和安全性问题。

物理与数据双驱动水风光短期功率联合预报研究

短期功率预报是保障可再生能源电站稳定运行的重要举措。针对多能互补系统功率预报难以考虑不同能源间时空相关性和预报误差互补特性的问题,提出了物理与数据双驱动水风光短期功率联合预报模型。采用WRF-新安江模型驱动气象水文要素预报,通过互信息方法识别功率预报的关键因子。基于长短期记忆网络构建功率联合预报模型,并将该方法应用于雅砻江流域官地水风光互补系统。结果表明:①相较于独立预报模型,物理与数据双驱动的短期联合预报模型总功率预报平均绝对误差和均方根误差分别降低了9.62%和8.31%;②由于预报误差存在互补特性,系统总功率预报误差小于各电站功率预报误差之和;③相对于单独预报模型,水风光预报误差互补率提高了10.96%。所提方法可为水风光系统协同运行提供技术支撑。

七一灌区新型测控一体闸门的设计与应用

测控一体闸门在灌区的应用对提高灌溉水利用效率和推进信息化建设至关重要。根据七一灌区不同的渠道类别,设计了各种规格的新型测控一体闸门。其中,闸体采用一体式双导轨结构,配备直流电机驱动闸门启闭以控制流量,旋转编码器记录闸门开度,雷达水位计采集闸门上下游水位,应用闸孔出流原理计算渠道流量;闸门测控终端显示电机运行状态和渠道水位流量信息,通过4GTD-LTE宽带无线通信专网远程传输至管理站和各级水务机构;采用风光互补的供电方式为测控一体闸门供能,能够满足至少10 d无风或阴雨天气用电需求。测控一体闸门的应用,改变了灌区以往水位流量曲线测流的方式,提高了测流精度,减少了灌溉用水的浪费。

Power Electronics:The Enabling Technology for Renewable Energy Integration

The markedly increased integration of renewable energy in the power grid is of significance in the transition to a sustainable energy future.The grid integration of renewables will be continuously enhanced in the future.According to the International Renewable Energy Agency(IRENA),renewable technology is the main pathway to reach zero carbon dioxide(CO_(2))emissions by 2060.Power electronics have played and will continue to play a significant role in this energy transition by providing efficient electrical energy conversion,distribution,transmission,and utilization.Consequently,the development of power electronics technologies,i.e.,new semiconductor devices,flexible converters,and advanced control schemes,is promoted extensively across the globe.Among various renewables,wind energy and photovoltaic(PV)are the most widely used,and accordingly these are explored in this paper to demonstrate the role of power electronics.The development of renewable energies and the demands of power electronics are reviewed first.Then,the power conversion and control technologies as well as grid codes for wind and PV systems are discussed.Future trends in terms of power semiconductors,reliability,advanced control,grid-forming operation,and security issues for largescale grid integration of renewables,and intelligent and full user engagement are presented at the end.

小样本下风光储耦合系统的新能源消纳能力概率评估方法

针对风光消纳面临的小样本不确定性问题,基于数据驱动混沌多项式展开法,提出小样本下风光储耦合系统的新能源消纳概率评估方法。首先,考虑风光储耦合系统的运行约束,提出以弃电率最小为目标的弃电率评估模型;随后,计及风光出力历史数据缺乏、难以采用传统不确定性优化方法处理问题,提出基于数据驱动混沌多项式展开法的弃电率概率评估算法。利用风光出力的多阶矩构建任意混沌多项式,基于多维高斯积分求解展开项系数;最后,根据展开系数解析计算弃电率的高阶矩信息,并根据最大熵法求解概率分布。仿真结果表明,所提方法相比于蒙特卡洛模拟法计算效率显著提升。

煤矿源网荷储一体化建设模式研究

煤矿源网荷储一体化系统的运行目标为绿电作为煤矿生产支持性电源,力求最大限度的减小煤矿生产对电网的调峰需求。文章首先总结归纳了不同工作制下煤矿负荷的运行特性,结合该特性分析了风光发电与之在电力、电量上的匹配关系,得出了瞬时发电电力盈余较大、整体用电电量缺额较大的矛盾情况。针对此矛盾情况,分析了储能充放电流程以及其削峰填谷、平衡消纳电量的支持性作用。提出了微电网“源荷互动”的控制策略。

基于人工鱼群算法的水风光联合调峰优化模型

本文提出基于多Agent人工鱼群算法(MAAFAS)的,以剩余负荷均方差最小为目标函数的梯级水风光短期调峰优化调度模型。该模型充分结合了Agent算法的自主性和人工鱼群算法的全局寻优性,降低了约束的复杂性,易于获得复杂问题求解下的最优解。并以我国南方地区某流域的6座水电站,11座风电场,4座光伏电站组成的风光水电源互补系统为研究对象,从不同来水场景下(汛期、枯期)进行实例分析。结果表明:该模型可以有效地利用水电能源的调峰能力,平均提高负荷峰谷差降幅率到44.65%,缩小原始负荷峰谷差3300 MW,剩余负荷趋于平稳,便于风光能源的更好消纳,是一种实用性较强的水风光短期调峰优化方法。

“风光氢储”多能源融合系统港船综合应用适应性研究

为促进我国水路运输绿色、低碳、可持续发展,需要综合运用风、光、氢、储等多种可再生能源和技术构建港船多能源融合系统。本文从政策标准适应性、技术适应性、能源可供性、经济适应性和环保适应性五个方面分别对风力发电、太阳能光伏发电、氢能利用以及储能技术在港船多能源融合系统中的适应性进行分析,认为“风光氢储”系统的应用十分契合我国当前的能源战略和水运行业政策。

光伏和风电一体化系统中的电源管理与电子电路设计

光伏和风电一体化系统可以提高可再生能源的利用效率,降低能源成本。文章重点探讨了该系统中电源管理与电子电路设计的关键技术。针对最大功率点跟踪(Maximum Power Point Tracking,MPPT)算法,比较了传统方法与基于机器学习的新型算法,并评估了其性能指标。在并网逆变器设计和储能系统集成方面,深入分析主要拓扑结构、关键参数优化以及经济性。通过一个典型工程案例,评估了系统整体性能和经济环境效益。该研究为光伏和风电一体化系统的优化设计提供了重要技术支持。

基于水电深度开发的龙羊峡水风光蓄一体化基地电源配置研究

在能源发展新形势及新要求下,依托常规水电站建设抽水蓄能是推动水电深化利用和抽水蓄能发展的重要途径。为深入研究水电融合改造抽水蓄能的建设形式选择和容量配置方法,通过以水电扩机和水电结合开发的抽水蓄能为灵活调节电源,对龙羊峡水风光蓄一体化基地电源配置进行研究,基于一体化外送基地优化调度模型开展电力系统8760 h时序运行模拟,对包括水电扩机、可逆机组和储能泵站等建设形式和规模与风电和光伏进行优化配置。结果表明:加入水电融合改造抽水蓄能电站后,一体化基地调节能力增强,可配置更大容量的风光资源,推荐龙羊峡水电站扩机规模1200 MW,抽水蓄能电站装机容量4000 MW。所提基于时序生产运行模拟的抽水蓄能建设形式和容量配置方法对所在流域水电融合改造抽水蓄能的水风光蓄一体化基地电源配置提供参考。