基于氢气储能的热电联供微电网容量优化配置

以光伏系统、氢燃料电池、电解槽、储氢罐构建的热电联供微电网为研究对象,制定初始投资成本等年值以及年运行成本最小的优化目标,提出热电联供微电网热负荷满足率评价指标,针对系统运行的基本约束设计微电网控制综合策略,并以某地历史源荷数据为参考,建立满足工程应用的数学模型,采用粒子群优化算法进行求解,得到氢气储能的孤岛型微电网热电需求基本方案。从应用层面论证氢气储能替代电池储能的可行性,并进行微电网系统容量优化配置,可满足居民负荷供能需求,提高系统运行经济性,预期具有较好的应用前景。     

超市热电联供系统余热利用及热电冷联供系统研究

通过建立数学模型对热电冷联供系统在超市中应用的可行性进行了分析。利用该模型对系统的节能效果、投资回收期、发动机组容量、等效满负荷运行时间等特性参数进行了研究，并对不同控制方式对系统性能的影响进行了讨论，为超市热电冷联供系统的方案优化提供了依据。     

热电联供系统的效益分析

一、前言 热电联供或热电冷三联供是一种先进的供能系统,其特点是能提高一次能源利用率、实现能量分级利用,并能按用户不同的要求进行设备工况灵活组态,在计算机系统的支持下构成智能化的供能网络。因而近年来这类系统一直受到世界各国动力界的青睐并多次成为国际能源会议的中心议题之一。     

上海市热电联供的回顾与建议

上海市的热电联供是从1958年开始,1911年始建的杨树浦电厂,在这一年打破长期以来单一供电的界限,开始向邻近的纺织厂供应蒸汽。 同年,为配合吴泾化工区的建设,吴泾热电厂起步建设并于1960年向用户供热。 随着石油工业的发展,1971年浦东高桥热电厂建成,向以上海炼油厂为龙头的高桥石化公司供热。1976年起金山热电厂建成,向金山石化总厂供热。     

基于生命周期微网的经济性分析

针对微网经济分析指标体系不系统、不科学等问题,提出了基于生命周期综合考虑各分布式能源经济运行状况、对环境和不同种类负荷造成影响等因素,确定了各分布式能源等年值投资、拆卸、治污、负荷停电赔偿费用以及碳贸易、可靠性、政府补贴效益等来量化微网成本与效益的经济性指标。通过对算例4种微网方案进行经济性分析,验证了理论可行性,同时研究结果为微网投资决策提供了科学依据。     

Risk-based optimal operation of power,heat and hydrogen-based microgrid considering a plug-in electric vehicle

The growing interest in integrating variable renewable energy resources (RES), besides global concerns about greenhouse pollution, brings multiple challenges for eco and environmentally-friendly operation of systems. Meanwhile, the simultaneous energy supply can improve energy efficiency and mitigate the fluctuation of RES compared with a single-energy system. Therefore, this paper seeks to investigate the optimal scheduling of heating, power, and hydrogen-based microgrid incorporated with RES and plug-in electric vehicles (PEV). The fuel-cell-based hydrogen and electrolyzer facilities are integrated into the multi-energy system to investigate the power-to-hydrogen and hydrogen-to-power technologies in the model. Besides typical electric and thermal loads, the proposed system can directly sell hydrogen to hydrogen-based industrial applications. The PEV as a flexible resource is employed to facilitate the integration of solar energy. Due to the substantial uncertainty from solar energy, price, load, and EVs' arriving and departing times, the risk management of the model based on the conditional value-at-risk is developed to show the operator's behavior against the random inputs and their risk. Results show that integrating the hydrogen storage and plug-in electric vehicle in the model results in a daily cost reduction of up to 9.28%.     

基于粒子群算法的储能电站经济优化调度策略

储能电站的功率分配方案直接影响其调度成本,合理的功率分配方案是保障电站运行经济性的基础。为了合理有效地进行储能电站功率分配,文章以单位周期内调度成本最低为优化目标,搭建了考虑电池容量损失的储能电站调度成本模型,并利用粒子群优化算法(PSO)寻求储能电站调度任务的最优分配方案。在保证完成储能电站调度任务的同时,最大限度地降低调度成本。案例仿真结果表明,文章所提出的PSO优化分配方案比传统等比例功率分配方案具有明显的优越性。当储能电站在传统调度方法下寿命终止(1 597次)时,PSO优化调度方法同比节约调度成本约19.7%,且在此基础上可继续工作370次,使储能电站的运行寿命延长23.2%。     

考虑储能优化的直流微电网协调控制研究

文章提出一种基于移相控制双半桥变换器的独立直流微电网协调控制策略。该策略以稳定母线电压和平衡系统有功功率供需为主要目标,根据母线电压波动改变移相角控制储能电池功率,确保独立直流微电网稳定可靠运行。采用双半桥变换器可实现储能电池电气隔离,移相控制可提高双半桥变换器升压比,进而提高储能系统的安全性。利用Matlab/PSIM联合仿真平台搭建独立直流微电网模型进行分析,仿真结果表明该协调控制策略可稳定储能电池输出功率,扰动发生时电压波动小、响应速度快,有效提高了系统可靠性。     

垃圾焚烧电厂热电联产的经济性分析

合理利用垃圾资源进行热电联产,是节能减排、改善环境的有力措施。以某2×750 t·d^-1垃圾焚烧电厂为例,通过模型研究发现热电联产可以减少垃圾焚烧电厂的冷源损失,提高全厂热效率;利用一抽蒸汽进行热电联产可实现蒸汽品质的梯级利用,获得较高的经济效益;供热量为30 t·h^-1,垃圾热值由4185.9 kJ·kg^-1增加至8371.7 kJ·kg^-1时,发电量越多,供热能力越强,年热电联产经济效益由7822.76万元增加到14641.07万元;垃圾热值为8371.7 kJ·kg^-1,供热量从10 t·h^-1增加到60 t·h^-1时,垃圾焚烧电厂热效率从28.96%增加到48.50%,年经济效益从13602.74万元增加到15455.66万元。当该地区垃圾热值较高并具备供热条件时,实现垃圾热电联产具有较高的收益。     

Performance improvement of combined cycle power plant based on the optimization of the bottom cycle and heat recuperation

Many F class gas turbine combined cycle(GTCC)power plants are built in China at present because of less emis-sion and high efficiency.It is of great interest to investigate the efficiency improvement of GTCC plant.A com-bined cycle with three-pressure reheat heat recovery steam generator(HRSG)is selected for study in this paper.In order to maximize the GTCC efficiency,the optimization of the HRSG operating parameters is performed.Theoperating parameters are determined by means of a thermodynamic analysis,i.e.the minimization of exergylosses.The influence of HRSG inlet gas temperature on the steam bottoming cycle efficiency is discussed.Theresult shows that increasing the HRSG inlet temperature has less improvement to steam cycle efficiency when itis over 590℃.Partial gas to gas recuperation in the topping cycle is studied.Joining HRSG optimization with theuse of gas to gas heat recuperation,the combined plant efficiency can rise up to 59.05% at base load.In addition,the part load performance of the GTCC power plant gets much better.The efficiency is increased by 2.11% at75% load and by 4.17% at 50% load.     

Multi-objective planning and optimization of microgrid lithium iron phosphate battery energy storage system consider power supply status and CCER transactions

Lithium iron phosphate battery (LIPB) is the key equipment of battery energy storage system (BESS), which plays a major role in promoting the economic and stable operation of microgrid. Based on the advancement of LIPB technology and efficient consumption of renewable energy, two power supply planning strategies and the china certified emission reduction (CCER) model are proposed respectively. Based on it, the multi-objective planning optimization model with economic benefits, environmental benefits and power supply stability as the objective function is established for the first time, and the Newton Weighted Sum Frisch method (NWSFA) solution model is adopted. In the planning process, rain flow counting method is used to research the life of BESS, which improves the accuracy of energy storage annual cost calculation. A park in northern China is taken as a case study to demonstrate the application of this model. The simulation results show that the annual economic operating cost of BESS is decreased by 18.81%, the energy supply reliability is increased by 0.15%, and the optimal electricity price adjustment ratio of the system is 15%.     

Economic optimization of shell and tube heat exchanger based on constructal theory

In this paper, the new approach of constructal theory has been employed to design shell and tube heat exchangers. Constructal theory is a new method for optimal design in engineering applications. The purpose of this paper is optimization of shell and tube heat exchangers by reduction of total cost of the exchanger using the constructal theory. The total cost of the heat exchanger is the sum of operational costs and capital costs. The overall heat transfer coefficient of the shell and tube heat exchanger is increased by the use of constructal theory. Therefore, the capital cost required for making the heat transfer surface is reduced. Moreover, the operational energy costs involving pumping in order to overcome frictional pressure loss are minimized in this method. Genetic algorithm is used to optimize the objective function which is a mathematical model for the cost of the shell and tube heat exchanger and is based on constructal theory. The results of this research represent more than 50% reduction in costs of the heat exchanger.     

Thermoeconomic analysis based on energy structure for combined heat and power

This paper proposes a unified comparison method for the calculations of thermodynamic efficiencies applied to combined heat and power (CHP) plants. Two new dimensionless indices are introduced. They are used to estimate the influence of technical and economical features on the profitability of a CHP plant. A case of a CHP installation by internal combustion engine is treated as a practical application.     

考虑用电优质系数的微电网分段混合策略优化调度

考虑需求侧响应的并网型微电网调度常忽略光伏出力特性对可控负荷调度的影响,且缺乏完善的需求侧评价指标。文章提出一种PVP&LS(Photovoltaic Priority&Load Shifting)分段混合调度策略,PVP策略依据预测光伏出力,以弃光率最小为目的调控可控负荷;LS策略以降低峰谷差率为目的,对上阶段剩余可控负荷移峰填谷。同时,提出了改进的用电优质系数模型,不仅避免调控过度,还可量化用户感受。最后通过自适应遗传算法仿真对比,运行成本减少了3.91%,用电优质系数增加了4.09%,弃光率下降了10.2%。