光伏发电系统输出功率计算方法研究

准确计算光伏发电系统的输出功率,对光伏发电系统发电量的监管和光伏并网系统与电网调度、电力负荷等的配合问题具有重大意义。根据光伏发电系统的结构和工作原理,提出了光伏发电系统输出功率计算方法,可以计算任意太阳辐射量、环境温度、系统结构下的光伏发电系统输出功率。通过与真实光伏电站运行数据的比对,结果显示了光伏发电系统输出功率计算方法的适用性与准确性。     

基于遗传算法的直驱式海浪发电系统最大功率跟踪控制

针对直驱式海浪发电系统在非规则海浪中能量捕获效率较低问题,提出遗传算法控制方案。以规则海浪下发电系统模型为基础,推导出非规则海浪下发电系统输出功率模型。采用遗传算法对参数种群进行选择、交叉、变异、迭代,辨识出符合当前海况的最优发电系统参数,结合空间矢量控制算法实现发电系统最大功率跟踪控制。仿真对比结果表明,该算法能有效提高海浪发电系统能量捕获效率。     

基于超临界CO2朗肯循环的太阳能光热发电系统分析

基于太阳能光热发电原理,提出加装回热系统的发电系统模型,结合朗肯循环,以超临界CO₂作为工质,系统分析进气温度、进气压力对发电系统效率的影响,研究回热系统的热经济性。结果表明：低压状态下进气压力对发电系统循环效率的影响较大,高压状态下进气温度对发电系统循环效率的影响较大;压力增大时,发电系统效率先增后减,温度增加时,发电系统效率保持增加;与无回热系统相比,加装回热系统能够明显提升发电系统循环效率;发电系统的不可逆损失随着压力的升高而降低,随着温度的升高而升高,为基于超临界CO₂朗肯循环的太阳能光热发电提供参考。     

生物质气化斯特林发电单元系统设计

通过梳理现有生物质气化发电系统发电中出现的问题,提出了采用生物质气化斯特林发电单元系统.介绍了该系统的组成,分析了其球笼式框架结构、余热利用装置结构及散热系统结构,并进行了实验分析.实验结果表明,该生物质气化斯特林发电单元系统能有效提升发电功率,适合大规模建设分布式斯特林发电站发展的要求.     

10MW太阳能热气流发电系统结构优化与成本分析

针对太阳能热气流发电系统烟囱超高、集热棚超大的特点,基于太阳能热气流发电系统的流动与传热模型,预测了10 MW太阳能热气流发电系统的基本几何结构,建立了太阳能热气流发电系统各关键部件、整体系统的造价模型及发电成本模型.通过计算和对比10 MW系统各种几何结构型式的系统造价,获得了经济上较为合理的结构型式,并分析了影响集热棚、烟囱及系统总造价的主要因素,提出了降低系统造价的方法.结果表明,该方法经济、可行.     

风光氢混合发电系统设计与能量管理策略研究进展

风光氢混合发电系统是有效解决风电、光伏发电随机性强、波动大的缺点和提高系统供电可靠性的有效手段,也是未来发电系统的重要发展方向.然而,这种发电系统拓扑结构复杂,设备类型众多、特性复杂、控制模型多样,对系统结构设计和能量管理策略制定提出了较大挑战.文章从系统构成要素、设计思路和能量管理策略三个层面进行详细总结,介绍了系统...     

风电与燃气轮机互补系统发电成本敏感性分析

详细讨论了大型风电场与燃气轮机组成的互补发电系统发电成本的主要影响因子及其对系统的敏感性。通过对互补发电系统发电成本理论公式的研究,推导了互补系统中各项影响因子相对于发电成本的数学方程和影响尺度,得到了影响发电成本几个关键的影响因子。通过采用敏感性分析原理,对这些主要的影响因子在不同变化条件下对互补发电系统发电成本的影响进行了详细的分析与讨论,提出降低系统发电成本的可行性措施及其努力的方向,为在新疆地区实现这种互补发电系统提供经济分析上的基础。     

光伏发电并网大电网面临的问题与对策

妥善解决光伏发电系统接入大电网后2部分都能安全、高效运行是光伏发电技术大规模工业化应用的关键之一。分析了光伏发电系统及其并网的技术特点,简要阐述了光伏发电并网问题的研究现状。指出光伏发电大规模并网使大电网在研究与实验验证手段、对光伏发电系统影响大电网机理的认识、新型配电系统的规划、电网运行控制、电网监测保护与控制装备、技术标准与规范等方面面临新的问题,并提出了应对这些问题的策略。     

CO_2准零排放SOFC_MGT混合发电系统研究

基于顶层循环的SOFC/MGT混合发电系统,提出了CO2准零排放SOFC/MGT混合发电新系统:经电池堆阳极产物分离出氢气后采用纯氧燃烧,用冷凝的办法除去水蒸气,从而捕获CO2气体。阴极产物与分离得到的氢气则在另外的后燃室燃烧。结合案例分析了该混合发电新系统的性能,研究了CO2液化温度对系统的影响。与其它CO2准零排放发电系统相比,本研究提出的CO2准零排放SOFC/MGT混合发电新系统具有更高发电效率。研究结果将为CO2准零排放发电系统的研究提供有益参考。     

风能与水能互补发电系统的研究

论述了水能与风能两种自然资源特性及互补的必要性和经济性,在此基础上提出风能与水能互补发电系统,构建了风能与水能互补发电系统的结构图、探讨了互补发电系统的运行策略及仿真运行与设计。风能与水能的互补开发、综合利用可提高发电系统的可靠性与稳定性,是一种行之有效可再生能源的利用方式。     

Characteristic evaluation of a CO2‐capturing repowering system based on oxy‐fuel combustion and exergetic flow analyses for improving efficiency

A CO₂‐capturing H₂O turbine power generation system based on oxy‐fuel combustion method is proposed to decrease CO₂ emission from an existing thermal power generation system (TPGS) by utilizing steam produced in the TPGS. A high efficient combined cycle power generation system (CCPS) with reheat cycle is adopted as an example of existing TPGSs into which the proposed system is retrofitted. First, power generation characteristics of the proposed CO₂‐capturing system, which requires no modification of the CCPS itself, are estimated. It is shown through simulation study that the proposed system can reduce 26.8% of CO₂ emission with an efficiency decrease by 1.20% and an increase power output by 23.2%, compared with the original CCPS. Second, in order to improve power generation characteristics and CO₂ reduction effect of the proposed system, modifications of the proposed system are investigated based on exergetic flow analyses, and revised systems are proposed based on the obtained results. Finally, it is shown that a revised proposed system, which has the same turbine inlet temperature as the CCPS, can increase power output by 33.6%, and reduce 32.5% of CO₂ emission with exergetic efficiency decrease by 1.58%, compared with the original CCPS. Copyright © 2010 John Wiley & Sons, Ltd.     

Frequency deviation control by coordination control of FC and double-layer capacitor in an autonomous hybrid renewable energy power generation system

In this paper, a novel control strategy for frequency control in stand-alone application based on coordination control of fuel cells (FCs) and double-layer capacitor (DLC) bank in an autonomous hybrid renewable energy power generation system is implemented. The proposed renewable energy power generation subsystems include wind turbine generator (WTG), photovoltaic system (PV), FC system and DLC bank as energy storage system. The system performance under different condition has been verified by using real weather data. Simulation results demonstrate the validity of proposed studied hybrid power generation system feeding isolated loads in power frequency balance condition.     

基于电池储能系统和双重扩展卡尔曼滤波的风能发电智能调度技术研究

风能等新能源发电系统在供电体系中的占比越来越大,但其随机性和波动性问题,将风力发电厂输出的电力直接向电网调度会造成安全隐患。为了解决这一问题,基于电池储能系统提出了一种风能发电智能调度技术,该技术以风力发电动力学模型和电池储能系统状态模型为基础,利用双重扩展卡尔曼滤波算法实现了风能发电系统的稳定输出。以某地风速实测数据和电网需求功率为参考,对不同算法的输出功率预测值进行了仿真分析和实验对比。结果表明：提出的改进算法预测的风速值误差相比于传感器观测值平均误差降低了28%以上,可以更准确地提供发电系统输出功率;提出的智能调度技术可以使电压波动幅度降低60%以上,系统整体输出功率稳定在参考功率附近,误差不超过2%,有一定的实用意义。     

基于双层优化模型的风-光-储互补发电系统优化配置

提出一种基于双层优化模型的风-光-储互补发电系统优化配置方法,外层优化以互补发电系统年净收益最大化为目标、通过量子粒子群算法优化风-光-储容量配置;内层优化以互补发电系统日出力波动率和日出力峰谷差最小化为目标、通过8760 h生产模拟优化储能充放电功率。实际算例仿真计算结果表明,所提算法能有效解决风-光-储互补发电系统在规划阶段的优化配置问题。     

一种新型水泥工业余热与生物质能互补发电系统

本文提出一种新型水泥工业余热与生物质能互补发电系统,该系统采用水泥窑低温余热和生物质补燃有机结合的方式大幅提高水泥窑余热发电蒸汽参数与系统效率。来自水泥生产线窑头和窑尾的低温余热烟气全部用来加热工质水产生饱和蒸汽,饱和蒸汽进入生物质补燃系统中进行过热后送入汽轮发电机组中做功发电,补燃燃料为生物质气化燃气。本研究建立了单压和双压2种互补发电系统,分析了其热力学性能,结果表明:单压互补发电系统与传统单压纯低温发电系统相比,系统循环热效率和系统发电效率分别提高了1.63和1.92个百分点。双压互补发电系统与传统双压纯低温发电系统相比,系统循环热效率和系统发电效率分别提高了1.05和1.53个百分点。     

Characteristics and economic evaluation of a power plant applying oxy-fuel combustion to increase power output and decrease CO2 emission

This paper evaluates power generation characteristics, economics, and CO₂ reduction effects of a proposed CO₂-capturing repowering system that utilizes low pressure steam (LPS) to increase generated power and to capture generated CO₂ based on the oxy-fuel combustion method. A case study was adopted wherein LPS from a combined cycle power generation system (CCPS) is used. It is estimated that the proposed system can generate 2.03 times greater power compared to a conventional steam turbine power generation system (the reference system) using the same LPS, with an exergy efficiency of 54.2%, taking into account O₂ production power and captured CO₂ liquefaction power. The proposed system is estimated to be economically feasible (the depreciation year is estimated to be 4.78 years; BCR 2.50; and IRR 23.0%), and will economically outperform the reference system if CO₂ emission credit higher than 30 $/(t − CO₂) is applied for the captured CO₂. The effects of retrofitting the proposed system into the CCPS are estimated as follows: the net generated power can be increased by 27.9% and the CO₂ emission amount can be reduced by 21.8% with a 2.41% degradation of the net power generation efficiency, from 56.2% to 53.8%.     

Development of solid oxide fuel cell and battery hybrid power generation system

Solid oxide fuel cell hybrid generation system is the best scheme for the load tracking of off-grid monitoring stations. But there are still potential problems that need to be addressed: preventing fuel starvation and ensuring thermal safety while meeting load tracking in hybrid power generation system. In order to solve these problems, a feasible hybrid power generation system structure scheme is proposed which combined SOFC subsystem and Li-ion battery subsystem. Then a model of the hybrid power generation system is built based on the proposed system structure. On this basis, an adaptive controller, include the adaptive energy management algorithm and current feedforward gas supply strategy, is applied to manage the power-sharing in this hybrid system as well as keep the system operating within the safety constraints. The constraints, including maintaining the bus voltage at the desired level, keeping SOFC operating temperature in safety, and mitigating fuel starvation are explicitly considered. The stability of the proposed energy management algorithm is analyzed. Finally, the developed control algorithm is applied to the hybrid power generation system model, the operation result proves the feasibility of the designed controller strategy for hybrid generation system and effectively prevent fuel starvation and ensure thermal safety.     

Design and Optimization of a Full-Generation System for Marine LNG Cold Energy Cascade Utilization

This paper took a 100,000 DWT LNG fuel powered ship as the research object.Based on the idea of"temperature matching,cascade utilization"and combined with the application conditions of the ship,a horizontal three-level nested Rankine cycle full-generation system which combined the high-temperature waste heat of the main engine flue gas with the low-temperature cold energy of LNG was proposed in this paper.Furthermore,based on the analysis and selection of the parameters which had high sensitivity to the system performance,the parameters of the proposed system were optimized by using the genetic algorithm.After optimization,the exergy efficiency of the marine LNG gasification cold energy cascade utilization power generation system can reach 48.06%,and the thermal efficiency can reach 35.56%.In addition,this paper took LNG net power generation as the performance index,and compared it with the typical LNG cold energy utilization power generation system in this field.The results showed that the unit mass flow LNG power generation of the system proposed in this paper was the largest,reaching 457.41 k W.     

考虑分布式电源接入的电网源荷时序随机波动特性概率潮流计算

鉴于分布式电源的时序随机波动特性和负荷需求侧的电能质量是分布式电源接入系统的重要影响因素,从风光典型分布式电源和负荷需求的时序波动性出发,建立了综合考虑源荷时序特性的概率潮流计算模型。利用基于模糊特征聚类的概率潮流算法对IEEE 14节点系统进行计算,对比分析负荷需求侧对系统电压波动的影响情况。结果表明,所采用方法能够全面合理地模拟分布式电源接入时电网随机波动过程。